Armed to the Teeth: Bites from Forgotten Sharks

As the 31-day stretch of August rapidly rushes to completion, and the balmiest days of summer fade into the imminent, cool veil of fall, 2014 also discards one of its temporal landmarks associated with these heat-stricken days. If you think I am referencing something remotely anapestic and evoking chest-fluttering nostalgia of long-forgotten, canicular childhood summers, then think again. Because I am, of course, talking about Shark Week.
Yes, that now-legendary bit of the Discovery Channel’s summer programming line-up, a selachimorph-centered festival that is closing in on three decades running, has now passed us by, ending but two weeks ago. Years ago, Shark Week initially appeared to be driven with the mission statement of Discovery in mind, one rooted in the dissemination of fundamentally educational, science-based material in an entertaining manner. This incarnation of Shark Week was the one I was fortunate enough to grow up with, and this week was a boon to my insatiably science-curious child brain, one that my neurons practically salivated over in Pavlovian form right around the time the last traces of abandoned, burnt out firecrackers left July’s dirt. The gift of science education excellence was instrumental in the development of my eventual fascination (and career trajectory) with biology, and I credit the old-school Discovery Channel’s programming with much of the inspiration and intrigue about the natural world that gilded my early days.

At the age of four, my shark ID skills were solid. However, my artistic skills were still…er….buffering.

So, given the intimate intellectual relationship I have with Shark Week and Discovery, watching what both entities have become in recent years feels like a steel-toed kick to the kidneys. There are a laundry list of offenses, and all of them hit on a single formula; the sacrifice of ethics and scientific accuracy in favor of mythology and adrenal-gland massaging codswallop; a grand invasion of heart-pumping, flash and sparkle nonsense programming based on approximately zero micrograms of actual science, all as an ill-conceived motion to inflate ratings. Some examples of Shark Week contrived falsehoods? Well, there’s this lovely bit of mass hysteria-inducing, publicity-hungry deceit initiated by cries of “oh no! Lake sharks! *wink wink*.” Also, there’s that time Discovery trotted out this steaming, embarrassingly unscientific pile of horseshit. Oh, there’s also that other time they made an entire special up. Or how about how the network can only seem to convince scientists to do Shark Week specials with them if they straight-up con them into doing so?
Others (linked above) have done a splendid job of calling out the network’s recent, fraudulent Shark Week habits, so this post isn’t going to be yet another dart in that already well-pockmarked board, but what I want to address is loosely tied to Shark Week’s newfound adoration of Megalodon (well, specifically an adoration of tricking viewers into believing the very extinct shark is still patrolling the deep…now for two years in a row).

“Megalodon”, or to be more accurate Carcharocles megalodon (or Carcharodon megalodon, it depends on what paleontologist you ask) is a popular beast, and thus is an obvious choice for many an examination by television networks (in mockumentaries or not). The extinct shark species is popular for damn good reason, too. C. megalodon was an animal of such outlandish proportions that it doesn’t seem like it could ever have existed, and yet it did, for more than 26 million years, dying out right around the time our ancestral line first harnessed that hot, orange, light-producing stuff that eats up wood (followed swiftly by the invention of S’mores and crappy ghost stories). This was a shark that, according to the most conservative estimates, exceeded 45 feet in length, and had a pair of cartilaginous bear trap-esque chompers big enough to gulp down a Ford Fiesta without even scratching the paint on its immense, triangular teeth.
And oh yes, those teeth. Those frisbee-sized blades that festooned its jaws in a ragged chain of despair. Those famous teeth, for which the animal is named (megalodon basically means “giant fucking tooth”), combined with a body bigger than a goddamn school bus, have enraptured the imaginations of young and old alike, and contemplation about what it would be like to encounter such a surreal, monstrous animal in the flesh is unavoidable.

But, here’s the deal with ol’ Megs…outside of its status as by far the largest shark that ever lived, and definitely one of the biggest predators to ever exist (getting edged out by the sperm whales alive today)…as far as we can tell, there’s nothing insanely unique about its biology. Granted, one of the most fascinating things about C. megalodon is that we don’t know that much about it. Even the size of the thing is sort of up in the air, seeing as how the scientific community has only fragmentary remains (teeth and a handful of vertebrae; the cartilaginous skeletons of sharks don’t fossilize as readily as bony skeletons, so this dearth of recorded remains is not that unusual) from which to base their calculations; estimations range from the 40s of feet in length to more than 60 feet…which in my book is the difference between “we’re going to need a bigger boat” huge and “I’m going to need a new pair of pants” huge.
Honestly, C. megalodon was cool and all, but it was basically just a Hulked-out version of any large lamniform shark (Lamniformes being the order of sharks to which great whites and makos belong). The animal is more or less like a great white had a run in with Rick Moranis and his growth ray, with maybe some very subtle differences in proportions…and a slightly different taste in prey…like taking on goddamned whales instead of comparatively diminutive sea lions. Yes, C. megalodon was something of a specialized whale killer…a shark exquisitely well-adapted to slaughtering and consuming the most massive animals of all time.
So sure, it’s teeth were heart-stoppingly big, and robust, and belonged in the titanic jaws of a beast of celebrity status….but they were just relatively standard lamniform teeth ratcheted up in size, with some limited modifications for slicing through several hundred cubic feet of whale flesh and bone at a time (increased thickness and bigger, deeper roots).
For an animal so well-known for its mouth, it certainly didn’t have the most unique pearly whites among extinct sharks. The diversity of prehistoric sharks, and the diversity their feeding adaptations (which often are very divergent from today’s sharks), are woefully unappreciated, at least in comparison to C. megalodon, which is a remarkable shark due to its size and power…but I can think of a couple examples of long-extinct sharks that have far more interesting things going on at their eating ends.

Take Cretoxyrhina mantelli, for example, pictured below in this reconstruction by paleo-artist Dmitry Bogdanov, which given this speculative coloration, appears to be a shark that has deceptively splashed its belly in paint in a desperate attempt to mimic a great white shark.

I blame unrealistic standards of shark intimidation in the media.

Cretoxyrhina wouldn’t have had to try too hard to look like the most powerful predatory shark of today’s oceans (the great white), considering that they were very close relatives and reached similar sizes (although Cretoxyrhina likely got even larger, topping out at around 23 feet (7 meters) or more in length). Cretoxyrhina was a member of the same taxonomic order of sharks that great whites and C. megalodon belonged; Lamniformes, a group of sharks characterized by relatively conical snouts, five gill slits, and a mouth that sits behind the eyes. Cretoxyrhina was part of different family of sharks than today’s sea lion tossers, but they were more or less cut from the same evolutionary mold.

Cretoxyrhina patrolled global shallow seas between about 80 and 100 million years ago, meaning that it was separated from the most ancient great white sharks by the same immense length of time that modern humans are separated from the last of the dinosaurs. One of the places it called home, and where many high-quality fossil remains have been discovered, was Kansas. Cretoxyrhina didn’t frequent the Sunflower State because it craved barbecue and pursued the smells wafting out of Kansas City by crawling through wheat fields Land Shark style. Cretoxyrhina has fossils coming up in the heartlandiest part of America’s heartland because during the Mid-Cretaceous era, this entire region was covered by the Western Interior Seaway, a great swath of saltwater that divided North America longitudinally into two giant landmasses, running unbroken from the Gulf of Mexico to the Arctic Ocean. The notion that Kansas, and much of the American Mid-West, was a sea bed tens of millions of years ago isn’t that surprising considering that the region is flatter than twenty year-old can of Crystal Pepsi. It’s flatter than Bernie Lomax’s ECG. Flatter than that dusty, unused piano in your grandmother’s guest room. Flatter than how a joke about twerking falls at an AARP convention. What I’m trying to say is that Kansas is flatter than shit (and honestly, it’s kind of a dull, featureless, oppressive shithole, both due to the aggressive summer heat and the legions of hyperreligious, bug-fuck insane, freedom-fried inhabitants…sorry Kansans).

The Western Interior Seaway was an ocean that teemed with a rich diversity of marine life, and provided Cretoxyrhina with a smorgasbord of flavorful, finned fauna upon which to dine…and dine it did, with a set of some of the most impressive teeth to evolve in the hundreds of millions of years of shark prehistory. These knife-like teeth, some two inches long and numbering more than thirty in each jaw not counting the replacement teeth “on deck” (compared to the twenty-five or so in great white jaws), are graced with a unique characteristic of their construction; the presence of an unusually thick, resilient enameloid (similar to enamel, the hardest, outermost covering of human teeth) coating. These teeth had the impeccable sharpness common to predatory sharks in general, combined with an unprecedented toughness. Cretoxyrhina was equipped with teeth that were particularly good at biting into very hard, bony or shelled things over and over again, and successfully cutting them into manageable, bloody chunks. For this reason, Cretoxyrhina is commonly called the “Ginsu shark”, referring to the famous, supposedly exceptionally sharp cutlery hard sold via infomercial in the 70s and 80s.

It’s perhaps incredibly fortunate for Cretoxyrhina that it had this buzzsaw of a mouth at its disposal. The Mid-Cretaceous oceans, especially in the bountiful, warm, shallow waters of the Western Interior Seaway, were full of “difficult” prey items and “worrisome” predator competition…and by “difficult” and “worrisome” I mean that they would make today’s most effective and brutal marine predators jettison the contents of their bowels into the water column in a fit of terror. Middle America some 90 million years ago was a lukewarm cauldron full of an assemblage of aquatic monstrosities that appear to be lifted straight from the sketchbook of a deranged 8-year old child. Among them was Xiphactinus, a voracious, needle-toothed fish with a dramatic, bulldog-like under-bite and a body the size of a Chevy Tahoe. There were also plesiosaurs like Elasmosaurus, whale-sized, snake-necked reptiles that look more like something hunting in the subterranean oceans of Naboo than something that actually existed on Earth at one time. The seaway also was home to sea turtles that weighed more than two tons, and a number of mosasaurs like TylosaurusFor those unfamiliar, mosasaurs were a group of marine lizards that reached their heyday at the tail end of the Cretaceous, and were basically a hellish amalgamation of crocodiles, eels, and sharks…but blown up to the size of an orca. Wherever mosasaurs swam, they, understandably, were among the most dominant predators in their ecosystem. Similar throngs of animals were found in epicontinental seas (inland seas and seaways) and continental shelves (areas offshore where the continental plate is submerged in the sea; more shallow than the middle of the oceans), prime Cretoxyrhina habitat, the world over.
The “Ginsu shark” may have been an impressive fish, with its gob full of diamond-tipped blades and imposing bulk, but it was just one of many giant predators in the tepid Cretaceous oceans.

So, there was a glut of flesh, bone, and teeth during this time; on land there were still the big, non-avian (non-bird) dinosaurs, and in the seas, gigantic reptiles and fish. Cretoxyrhina was likely superbly adapted to exploiting food sources in these treacherous waters via its uniquely effective bite. Flourishing in a sea full of big, armored, active animals means you have to have the capacity to take a shot at just about anything…and it appears as though Cretoxyrhina did just that. Cretoxyrhina teeth and bite marks are found in just about every big animal it shared the water with; Archelon, the largest sea turtle to have ever existed, got jacked up by this shark…the shark tore into giant pleisosaurs….and even went after the biggest and least-fuck-withable things around, mosasaurs. It is often hard to tell from the fossil evidence whether or not affixed teeth or scarring on bone is the result from an actual attack and feeding, or simple posthumous scavenging. However, there are examples in the fossil record of Cretoxyrhina making a failed attempt at a kill of a mosasaur, evidenced by the mosasaur’s vertebrae having shark teeth embedded within the bone, where the injury became infected, subsequently healed, with the bone growing over the tooth like a tree trunk slowly enveloping a fence over decades. Think about that for a second; mosasaurs, a predator group so heinous that it likely had an impact on the decline of entire orders of other humongous, fang-toothed, marine reptiles like pliosaurs and ichthyosaurs, were a menu item for Cretoxyrhina. Even if most of its interactions with the largest predators and prey in the ocean were, realistically, opportunistic events where it fed on small, young, or sick individuals, or just devoured the dead…the Ginsu shark assuredly occasionally used those incredible teeth against things that were very big, very strong, and very dangerous.
Cretoxyrhina wasn’t the baddest bastard under the waves, but outfitted with a bite that could cleave several inches of bone in an exposed mosasaur flipper as effortlessly as a light saber carving through a gelatin salad, it sure as shit acted like it was. C. megalodon may have chiefly fed on giant whales…but baleen whales don’t have the ability to fucking bite back, and for that reason, Cretoxyrhina’s comparably courageous habit of recklessly targeting actual, real life sea monsters as food, as if it’s filming an episode of Jackass, receives an award for Heftiest Gonads of Shark Prehistory, at least in my book.

A second shark with a special set of teeth actually lived in the Western Interior Seaway during the same era as Cretoxyrhina, but this shark fed itself in a way not often associated with anything vaguely related to the common conceptualization of how a “shark” is supposed to make a living. A major part of this reason is because this shark had teeth that looked very similar to these:

Less with the “serrated death dagger” and more with the “wrinkly elbow” look

These teeth belong to a species of shark in the genus Ptychodus. Ptychodus was one of the last remaining examples of a group of sharks known as hybodonts (order Hybodontiformes). Hybodonts evolved more than 300 million years ago, and were incredibly common throughout the “age of the dinosaurs”, but eventually were out-competed by more sophisticated, less primitive sharks and died out sometime near the end of the Cretaceous. At the very end of their time on Earth, some bizarre, specialized forms had evolved, and Ptychodus was one of them.

Ptychodus had a set of jaws packed with rows of flat, bottle cap-shaped teeth arranged in a dense formation that resulted in a functional “plate” in both upper and lower jaws, opposing each other. This meant that Ptychodus obviously had a vastly different dental set up compared to other contemporary sharks, with much of the jaw toothless, save for this odd battery of bumpy hubcaps crammed together at the very front of the face.

It also meant that it had jaws that weirdly resembled the human female reproductive system.

It is thought that these mouths full of molars were an adaptation to feeding upon a very specific, and very locally abundant quarry; shelled animals, particularly clams. This type of feeding on tough, hard-shelled organisms, involving using broad teeth and powerful jaws to crush the shell outright, is known as “durophagy”, and outside of the limited number of species of bullhead sharks, it is not a strategy employed by modern sharks. We don’t know a whole lot about what they looked like and how they behaved, but given what we know about living sharks that have slow-moving prey that stay close to the bottom, we can surmise that Ptychodus had similar characteristics, in that it was likely slow-swimming (since hunting clams and urchins and other spiny, shelled critters doesn’t exactly require much chase) and resembled sharks with similar habits, like a nurse shark, for example.
This dietary specialization is unique, but one species of Ptychodus, Ptychodus mortoni, unearthed in Kansas several years ago, takes the entire game to a whole other level by being huge, based on calculations from fragmentary remains. How huge? Ten meters huge. That’s longer than a lot of sailing yachts.

P. mortoni was among one of the largest sharks of all time (and certainly one of the largest durophagous creatures of all time), and if it were alive today, it would only be exceeded in mass by whale sharks and the occasional basking shark…so it must have been eating bucket loads of clams to sustain itself, right? Not necessarily, at least not the types of clams you and I are familiar with. The Western Interior Seaway was also inhabited by a giant organism of a different stripe; Platyceramusthe most titanic genus of clam to ever sit, boringly, in the loose silt at the bottom of the sea. It was a clam with a shell that, at its smallest was bigger than your bulkiest, most airline-unfriendly piece of luggage, and at its largest, could fill an entire living room. A single individual could produce enough clam chowder to quell the hunger of a hundred famished New Englanders. Platyceramus was so insanely colossal that it served as a micro-ecosystem in and of itself, being utilized as protection for scores of fish, as well as a substrate for other shelled animals to attach and grow. This mega-mollusk, which makes the giant clams of today look like dinky, littleneck clams, was likely splintered by the insatiable car compactor jaws of P. mortoni, and the great underwater fields and reefs of these clams that once lined the shores running up and down the soon-to-be Great Plains could have been a major source of food for such a giant fish.

It’s unknown exactly what brought an end to P. mortoni. During the latter part of the Cretaceous, hybodont sharks were being outpaced by “newer models” of sharks, generally speaking, but given P. mortoni’s level of dietary specialization, traumatic ecological competition doesn’t seem too likely, unless some other giant durophagous fish rears its head in the Kansan fossil record. It’s also unclear if this shark was a victim of the same extinction event that leveled the non-avian dinosaurs, marine reptiles, and pterosaurs. A third route for its extinction might be linked to its selective diet, and the fact that, as of right now, has never been found outside of the range of the Western Interior Seaway. The seaway eventually closed as the Cretaceous transitioned into the Paleocene, and with it went all the habitat that made such rich grounds for an endless supply of outsized clams. It is possible that even if this last holdout of the hybodont family line managed to slip past millions of years of competition and an abrupt, catastrophic, global extinction event…it could have fallen victim to the incredibly common ecological and evolutionary phenomenon of being exceptionally good at a far too few number of jobs; the biggest species of Ptychodus did a wonderful job of scooting along the bottom of the ocean, shattering clam beds like a steamroller making its way through a ceramics class…but once the clams are gone, unemployment hits swiftly. Unfortunately, ecological unemployment tends to be irreparable, and fatal.

Either way, much like the limelight awash C. megalodon, both these other noteworthy sharks and their astonishing bites are forever lost to the lonely, backward expanse of time. It’s been many tens of millions of years since Cretoxyrhina last unwisely harassed the most decidedly inedible animals to ever evolve on this planet. Ptychodus hasn’t lazily busted open a couch-sized clam in almost that long. No modern human has ever had the undoubtedly epic experience of seeing these three animals alive, and barring the eventual invention of time travel, no human ever will. These animals, along with their incredible teeth, feeding behaviors, and overall biology, are quite dead.

We should consider ourselves lucky that a diversity of groups of sharks made it out of the Mesozoic era and arrived at the present day, continuing their several hundreds of millions of years of existence in our oceans. Multiple lineages of sharks today depart from the archetypal “tooth torpedo” form many of us have assigned to sharks, and engage in a wide array of unique feeding strategies. Unfortunately, many of these sharks are also threatened with extinction. Some hammerhead sharks use their hammer-shaped cephalofoil, armed with a high density of electroreceptive sensors, like a finely tuned metal detector, searching for the slightest signs of stingrays partially buried in the sediment at the bottom of the sea, which are then pinned down in a flash of cartilage-on-cartilage savagery and ingested after being rooted out from their hiding place. These remarkable sharks are also distinctly endangered, with two species currently regarded by the IUCN as endangered, and another as vulnerable. The whale shark, an enigmatic, beautifully serene animal that feeds entirely on plankton via filter feeding in a very unstereotypical fashion (for a shark), equipped with a mouth shaped like an envelope slot and with its closest relatives consisting of tiny, bottom-dwelling, camouflage-embracing sharks, is also the world’s largest “fish”, growing to more than 40 feet in length. It too is considered to be vulnerable to extinction, with major causes of concern of population decline stemming from fisheries that target the sharks, to habitat loss and depletion of the quality of feeding waters. The river sharks of the genus Glyphis are remarkable solely for the fact that they live completely within freshwater river systems, unlike any living sharks (bull sharks are renowned for their ability to access fresh and brackish water, but these sharks depend on saltwater for reproduction and are therefore not truly freshwater animals). River sharks are so rarely sighted (and as a consequence, so poorly understood) that it’s possible we haven’t identified all members of the group yet, and some of the ones we know about are undoubtedly critically endangered, especially those constricted to heavily polluted and overtaxed river basins in Southeast Asia. Sawfish, while not actually sharks (they are instead rays), grow to very shark-like body sizes and use an amazing, tooth-studded, electrosensor-lined bill to detect and stun/impale prey from its position on the muddy bottoms of lagoons, estuaries, and river deltas. Not a single accepted species of sawfish isn’t immediately endangered with extinction.

It is far too late to observe Cretoxyrhina or Ptychodus, but the exceptional elasmobranchs I listed above are modern. They exist as a part of our present day world, at least for now. Whether or not they begin to fade into the permanence of the fossil record, one by one, is largely up to us.

Image credits: Tooth intro image, Cretoxyrhina, Ptychodus teeth, Ptychodus jaw

© Jacob Buehler and “Shit You Didn’t Know About Biology”, 2012-2014. Unauthorized use and/or duplication of this material without express and written permission from this blog’s author and/or owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Jacob Buehler and “Shit You Didn’t Know About Biology” with appropriate and specific direction to the original content.

Macabre Moths: The Infernal Nocturnals

My girlfriend is terrified of moths.

She hates them; purely, unabashedly, and completely. She despises their habit of gracelessly barreling out of the dark, smashing into anything and everything (including human faces) in a flurry of fluttering wings. She hates the way they persistently ram themselves into outdoor lights,  which oh-so conveniently tend to be right above her head just outside of the front door, cutting her off from the frustratingly close safety of her house. She loathes the angry drumming sound they make when they clumsily bat their wings against whatever wall or window they are crawling across. She shivers at the mention of their wings, which she describes as “dusty” (the powdery coating is actually made up of very tiny scales that cover the wing; butterflies have these as well). I’ve watched her spot a particularly massive, beastly, mothy bastard spread out sinisterly underneath a neighbor’s outside window sill, and immediately swing her path past it into a wide berth, eyes cautiously locked on the insect threat. She does not like them here or there. She does not like them anywhere. My girlfriend does not like the moth. She does not like them, David Lee Roth.

Because of her undeniably real, demonstrably intense dislike of moths, she was not exactly appreciative of the fact that the last week of July (July 19th through July 27th) was National Moth Week (or of the fact that I’m writing this blog post at all, frankly). For those of you that are unfamiliar, National Moth Week, started in 2011, is a global citizen science effort wherein groups of those inclined (called “moth-ers”, but I like to call them “moth-heads”) set out into the night equipped with lights, a white sheet, a bait mixture made of something like rotten fruit, molasses, or beer (preferably not the good shit; stick to domestic swill like Bud or Coors), and perhaps a camera for recording purposes…all of this to observe and categorize whatever moths they find attracted to their lights or bait, and to potentially contribute their findings to a multitude of databases. In this bit of crowdsourcing of data collection, we are able to know a bit more about the distribution of moth species (and for many species, where they turn up in the world is not well-known), and their general abundance over time, which is important to keep track of, considering that moths are good early indicators of decline in an ecosystem’s ecological health. Another major focus of National Moth Week is to bring awareness to moths, which are oftentimes regarded as boring, drab nuisances instead of the diverse, often colorful, interesting animals that they are. NMW also provides an opportunity to get groups of school age children together to not just learn about moths and the natural world that surrounds where they live, but to take part in a globally held citizen science project, hopefully inspiring some of them to take interest in the biological sciences in a more permanent sense.

Truthfully, moths are far more interesting than we give them credit for. They are diverse in form, size, coloration, and behavior. They are unfortunately pegged as dull creatures, which, at their best, are annoying, and at their worst, a pest that destroys clothes and crops. There’s a single thread runs through their popular characterization; one that paints moths as fundamentally benign, like a house fly, or a slug…something to put up with, and nothing to get too excited about; the “white bread” of the insect world. But, while it’s important to remember that moths are interesting by being incredibly important members of their ecological communities, as insatiable, leaf-obliterating larvae, as pollinators of flowering plants, or as nutrition for everything from birds to bats…there are a number of species that solidly destroy the notion that moths are innocuous at the acutely individual level. Some species are downright threatening, blatantly ignoring the memo about how moths are “supposed” to be the awkward, dirty, night shift butterflies of the world and nothing more disconcerting. These species, twisted, creepy, grotesque, and malicious even by arthropod standards, make it difficult for me or anyone else to dismiss my girlfriend’s mottephobia (the fear of moths) as being unfounded.

First, behold Chionarctia nivea, a superficially normal-looking type of icy white “woolly worm” moth that frequents the frigid northern reaches of Russia and East Asia, where, based on the elegant evening wear it has on in the photo below, it apparently flutters around perpetually dressed like Galadriel.

“I give you the light of Eärendil, our most beloved star. May it be a light for you in dark places, and a place for you to slam your face into over and over again in confusion and blind desperation. “

It’s a nice looking moth. Personally, I dig the sleek, streamlined thing it’s got going for it, and the titanium white coat gives it a classy aesthetic. It lives a very mothy life, doing lots of the typical mothy things. There’s nothing observably alarming or offensive about this species, which conveniently disguises itself as a cottonball, which is perhaps the mascot for unblemished innocence. This is a good, clean moth you can trust. This is a moth that pays its taxes, that always drives 5 mph under the speed limit, and has superb credit. This is a moth who you might feel comfortable voting for in the upcoming school board elections, because this moth has integrity, goddamnit, and integrity is hard to find these days.

But the males of this species conceal a disturbing secret…

With a bit of air pressure, the Chionarctia nivea moth deforms its abdomen into an awful assembly of alien French ticklers, unfurling bits of prickly, translucent membrane into the world’s worst precursors to balloon animals.
So, why? Why do the dude moths in this species insist on extruding these visually comfortable and vaguely threatening ass tentacles, immediately transforming themselves into something that looks like it would terrorize Kurt Russell in an Antarctic research station? And what do these organs do?

If you are asking yourself if the male-specific, extendable, phallic appendages are “a sex thing” then your suspicions are correct. These are totally a sex thing. But these love balloons ain’t for the actual moth hanky-panky. They are instead used in the initial wooing of females of the species. These organs (called “coremata”, and are found in lepidopterans (group of insects that includes moths and butterflies) in general) are lined with bristly structures called “hair-pencils”…and these hair-pencils write the language of sweet, sweet, moth-y love.
Well, to be more specific, they release a cocktail of pheromones that advertise to the female moths that the owner of those sexy coremata is a choice mate. When a male moth gets wind of far-spreading female pheromones, he tracks her down, and once close enough, he puffs up those fuzzy butt feelers like a pair of inflatable, advertisement airdancers and lets loose his intoxicating cologne. If the lovely lady is satisfied by what her antennae are picking up, the two love bugs can commence with the bumpin’ of abdomens.
The hair-pencil pheromones also appear to have a repellent effect on other males of the species. Once the stank of another bro moth’s sex solicitation juices are mucking up the air somewhere, it’s a bit of a turn-off to all the other males, apparently.

So, one species’ sickening “I don’t know what it’s doing, but get that fucking thing away from me” is another species’ steamy courtship display.

Alright, you say, so some species of moths have males that are particularly…er…”well-endowed”…with respect to their creepy, pneumatic, romancin’ not-penises. Big deal. It’s not like they are actually doing anything malicious. You are, perhaps understandably, unimpressed with this example of moth malice.

So, I say, consider the following scenario:
It’s a warm, humid night in the outlying, forested areas surrounding Vladivostok, Russia. There’s not much of a breeze tonight running onto shore from the Sea of Japan, and the air is thick. You are sitting out on your porch, drinking a Yarpivo Amber, trying, in vain, to use the night air to cool yourself. The coniferous forest around you is alive with the songs of crickets, and the darkness enveloping you, and the alcohol trickling from your blood and into your brain allow a blanket of relaxation to drape over you. Just before you drift off to sleep, a wayward, winged insect visits your position under the white intensity of your porch light. It’s a nondescript, little brown moth, and it delicately settles all six of its petite feet upon the back of your hand. You’re careful not to move and scare it off as you watch it wander back and forth across your hand, stumbling over the occasional hair, antennae twitching and wings wavering slightly to keep balance. You are instantly calmed by this intimate moment, briefly connecting with nature. An angel of the forest has stopped by and offered you the gift of its presence, and you feel as though the two of you are communicating on some kind of deep, ancient, spiritual level.
Just as a smile begins to illuminate your face, you watch as the moth slowly and deliberately unrolls its long, fragile proboscis…and proceeds to drill the end of it into the skin between your knuckles. Pain and shock jolt you to full, electric alertness as the moth plunges the sharp tip of its tubular tongue into your flesh and greedily laps up your blood like a cat at a water dish.

You’ve just had a run-in with the vampire moth, Calyptra thalictri.

Most adult moths and butterflies are passive nectarivores, and spend their days daintily sipping sugary nectar from wildflowers and flitting about as if their entire lives were an extended, sunny, spring tea party.
But not Calyptra, along with its close relatives in a small subfamily of owlet moths (Noctuidae). These guys, much like the mosquitoes and bedbugs were are more familiar with, are hematophagous, meaning that they feed upon blood. Calyptra is a branch of the moth family tree (native to much of southern Europe, Asia, and sub-Saharan Africa) that has taken a hard, evolutionary turn away from an existence dipping into daisies, and has made a serious of concerning, demented life and dietary decisions that would surely put a smile on the face of Bram Stoker’s corpse. Calyptra moths could give less than two shits about your cute little set of flower boxes outside, and are more interested in bringing pain to your veins.
That “butterfly” that supposedly flaps its wings and sets off a chain of meteorological reactions that culminate in a hurricane generating across the world? Yeah, that evil little bastard responsible for all that chaotic destruction (and by association, that godawful mid-2000s sci-fi thriller with Ashton Kutcher) was most certainly a moth named Calyptra.

Fig. 1, aforementioned evil little bastard

Only the males of the vampire moth indulge in the “scarlet nectar,” employing their surprisingly tough, rigid tip of their proboscis to puncture flesh, and unleashing a series of spring-loaded hooks that keep them from dislodging easily…allowing them to drink at their leisure. Calyptra moths tend to target large mammalian herbivores, like buffalo, elephants, and rhinoceroses as reservoirs of blood to stick their Straws of Torment into, but on a few occasions, humans have been…fortunate…to know the moth’s bite (particularly when it’s C. thalictri).

Let me be clear on the differences between being bitten by a vampire moth and being bitten by a mosquito. Female mosquitoes have highly specialized mouthparts molded by evolution into a sleek hypodermic needle, delivering a swift dose of blood-thinning venom after an expertly placed pinprick, followed by a seamless transition into hardly noticeable blood slurping. In contrast, vampire moths are working with a tool that is far better suited for piercing the skin of fruits in the search for sugary juices, than it is for living animal flesh…and this is because, unlike mosquitoes, and despite their name, vampire moths are not purists when it comes to the sanguinary dining thing. Male vampire moths are “facultative” blood feeders, meaning that, to them, blood is a “sometimes food”, and their diet is also rich in the happy, normal, not-you-or-me regions of the food pyramid. Calyptra and closely related moths are known for their ability to use their burly proboscises to tear into fruit for sustenance…obviously in rabid, vindictive frustration from getting to the flower weeks too late for nectar. This tool, wonderfully useful in giving a plum the worst day of its life, is woefully unsophisticated (compared to the mosquito’s instrument) when applied to big, ambulatory critters with touchy, inconvenient things like nervous systems.
The difference between getting bit by a mosquito and getting bit by a vampire moth is like the difference between having your blood drawn by a phlebotomist with a quarter-century of training and experience, or by Kevin, the disheveled tweaker with the “can-do” attitude secretly squatting in your neighbor’s shed. The mosquito gets the job done relatively painlessly and quickly with incomparable surgical precision. The vampire moth, on the other hand, opts for enthusiastically digging around in your forearm with a rusty lawn dart.

So, vampire moth bites are crude and painful for their entire duration because, unlike mosquitoes, these creatures don’t make their living from blood. There’s not as much reason to keep you or any other source of blood unaware of their feeding, and their craft is not honed or specialized. This is also part of the reason why these moths don’t pose any threat to people by way of disease transmission; the frequency of biting is too low and the feeding system is too inefficient. The frequency of hematophagy varies fairly widely among vampire moths, as well as the capacity to dig into fruits, with species capable of exploiting fruits along certain sections of a gradient of fruit skin thickness and hardness.

Inferences based on genetic studies of evolutionary relatedness among the group, seems to indicate that the evolution of the behavior doesn’t follow a pattern of supplantation of more primitive, vegetarian feeding modes (nectar, soft-skinned fruits) with more derived ones (hard fruits, blood), but rather that more recently evolved vampire moths simply have more of the feeding strategies available to them. More primitive moths in the group might only be able to probe squishy fruits, but moths like C. thalictri can have it all; thin-skinned fruits, thick-skinned fruits, fruits with a tough rind, people…you name it.

But why all the drama and gore either way? Why has Calyptra developed this propensity to temporarily ditch soft drinks, go full-on fucking Dracula, and cut straight to the hard shit? Flowers and fruit seem good enough for the rest of the moth and butterfly clan, so why does the vampire moth have such a needy palate?
Well, the reason may result from the practice of “mud-puddling”, which is an activity that involves far more bugs and far less mud-wrestling sexy times than you’d think (don’t lie, I know you were imagining it). If you’ve ever seen a bunch of butterflies very obviously touch down next to a shallow pool or puddle and gather around the muddy water’s edge like wildebeest at a watering hole, then you’ve seen mud-puddling. It’s very common among butterflies and moths, and the goal of mud-puddling is to suck up nutrients and salts found in things like mud, dung, and occasionally decaying matter (plant or animal). Mud-puddling tends to be a male-only hobby, and it’s thought that acquiring all these extra goodies has a key role in reproductive success. Males are often observed “gifting” females with these nutrients and salts alongside their sperm contribution. It’s essentially a ridiculously late, coitus-adjacent means of presenting a girl with flowers.
The extra nutritive boost can be of great value to any upcoming larvae to originate from such a pairing, since many caterpillar species feed on plants that are sparse in nutrients.
It is likely that blood-feeding, rather than serving as a food source for the adult male moths, provides another advantageous avenue for aspiring, prospective dad Calyptra to provide his progeny with health and vitality, as blood is literally piped around animal bodies as a nutrient, mineral, sugar, and amino acid smoothie.

Oh, and if you are currently residing in latitudes to the north of the temperate and tropical latitudes of Afro-Eurasia, and smugly reading this and acknowledging your comfortable space far outside the reach of the vampire moth…listen up.
Calyptra has been found, in recent years, to be expanding its range poleward into northern Europe, turning up in places like Finland, which is a place normally considered too cold for these bitey assholes. It’s very likely this invasion is due to recent, rapid, human-driven climate change effects, and that their residency in the north will become not only more extensive, but permanent. I’m relatively certain “influx of fucking blood-sucking moths” is some sort of karmic punishment for what humankind is currently doing to the polar bear.

“Alright,” you concede, “moths can be a little intimidating and off-putting. But not caterpillars! Those younger, squishier, tube-shaped versions of moths are just doofy, derpy, compulsively overeating herbivores! The adorable little buggers couldn’t be a threat to anything if they tried!”

Oh come on! It’s giving me puppy dog eyes!

To illustrate just how wrong that is, allow me to take your mind’s eye out into the middle of the Pacific Ocean, to the tropical archipelago where I make my home; Hawai’i. Hawai’i is celebrated the world over for its jaw-dropping natural beauty, with imposing, steep, eroded mountains covered in lush vegetation dropping dramatically down to idyllic white sand beaches. It’s touted as “paradise”, and after living here for a year and experiencing not a single day below 60 degrees Fahrenheit, and the freedom to snorkel along coral reefs and hike in gorgeous tropical rainforest year-round, I can definitely agree with the common, mythic conceptualization of the island chain.
In addition to being so eye-wateringly beautiful, Hawai’i is a remarkable laboratory of evolution, given its location thousands of miles from the nearest landmasses. A large proportion of the land organisms found in the islands are “endemic”, meaning that they are found nowhere else in the world, having evolved in complete geographic isolation from relatives on the mainlands of Asia and the Americas. They range from brilliantly-colored forest birds like the ‘i’iwi, to hardy plants found only along the slopes of volcanoes like the silverswords and greenswords, to a unique subspecies of bat. In keeping with the paradise aesthetic, most of what has evolved out here in the middle of the ocean isn’t much of a threat to jack shit, and especially not to invasive species brought in by human colonizers, which have, depressingly, turned Hawai’i into a laboratory of extinction in addition to one of evolution. With a dearth of many natural predators, whatever lineages were able to make it out here and spread across the islands often let down their defenses after millions of years of vacation. Just ask the moa-nalo, a group of geese-like birds that discarded their ability of flight. They suddenly, and curiously, dropped off the face of the Earth immediately after Polynesian settlers first arrived in the archipelago…it’s almost as if they were easy pickings for food. Weird how that works.
So yeah, a lot of the wildlife in Hawai’i are steeped in their own sickeningly sweet levels of isolation-driven innocence and vulernability. I mean, hell, even the spiders here have permanent happy faces plastered on their chipper selves.

This is not a place where you’d expect to find carnivorous goddamned caterpillars, but that is exactly what Hawai’i has to offer.

The caterpillars belong to moths of the genus Eupithecia, which are a highly speciose, diverse group of small, drab, nondescript moths also known collectively as “pugs.” They are found all over the world, and the vast majority of the time, their caterpillars are conventional, adorable, inchworm-like things, doodling around and munching on flowers and leaves and generally being about as terrifying as a clump of pocket lint.
But there a number of species in Hawai’i that have evolved into skilled ambush predators, lashing out at unsuspecting insects like a demonic spaghetti noodle and clasping them in spiny claws, turning their elongated bodies into a ravenous grappling hook, with all the merciless, direct brutality of a Mortal Kombat finishing move.

“Get over here!”

Good lord, is nothing sacred in this world? The last time I checked, the Very Hungry Caterpillar ate a lot of shit, but the still-beating heart of a fresh kill wasn’t on the menu.

Hawaiian Eupithecia caterpillars are a product of that evolutionary laboratory I was talking about. The other side of island critters no longer needing anti-predator defenses is the precarious ecological hole left by, you guessed it, no predators. The job position for predatory insects was left wide open since things like mantises weren’t able to survive the extreme distances out to the islands…and these caterpillars have eagerly filled it.

These little grubs of destruction have evolved a simple and effective means of striking fear into everything that flits and buzzes through the rainforests of the archipelago. They, not unlike many of their closest mainland relatives, mimic a small twig, making their gray and brown mottled bodies rigid and still, tightly gripping a branch with their hind feet and keeping the nasty business end erect and ready for action (note to self: Erect and Ready for Action is a great title for a porno). In this position they wait…and wait they do, until some terminally unlucky fly or beetle strays just a little too close. As far as other insects are concerned, the butt end of the caterpillar is just a knobby extension of a branch…and totally not studded with sensitive bristles that instantly alert the head end that dinner has arrived, prompting a lightning fast spasm that brings Mr. Fruit Fly face to face with three pairs of sword-shaped limbs and a glistening battery of sharp, salivating mandibles. Eupithecia arches itself in a tight loop, and like a bullwhip tipped with meat hooks, dispatches its target with deadly speed and accuracy…like a wormy falcon snatching a sparrow out of the air with its talons. The hapless insect doesn’t even have a chance to react, its life is pathetically brought to an abrupt end by the world’s most murderous larva.

Aw, it’s kind of cute; like a sleepy tiger licking its paws after disemboweling your whole family.

It’s possible that there are a number of traits already a part of pug moth caterpillar biology that may have served as “pre-adaptations” to a predatory lifestyle, and made transitioning from passive vegetarianism into being the most malicious maggots in town particularly easy. Their characteristic paroxysmal attack method might have its evolutionary origins in a defensive snapping behavior, in which an attacking bird or lizard might be stunned by the quick movements just long enough for the caterpillar to flop down to safety. This behavior could have been co-opted into their hunting technique quite effectively.The evolutionary transition to an insect-based diet might have been eased by Eupithecia’s tendency to consume specific parts of plants, like flowers along with their protein-rich pollen. A diet already pre-adapted to consisting of high-protein foods may have made switching from salad to steak easier than it would for many other vegan creepy-crawlies.

“Ok,” you start, “Hawai’i’s got some pretty homicidal moth babies. It’s a good thing I’m not a bug, or then I’d have something to worry about. Luckily, there’s no caterpillar that could possibly impact my health or well-being.”

Yeah, no. Not even fucking close.

Meet Lonomia, a genus of moths found in South America that are closely related to the stunningly patterned and gigantic atlas and luna moths. However, the adult Lonomia moths are far more conservative in coloration than their more famous family members, choosing to go with subtle camouflage against the backdrop of their woodland home. This is not an unusual strategy among moths.

Oh, you look like a brown leaf? Wow, groundbreaking creativity.

Lonomia caterpillars are also gifted with the ability to blend in, but are covered in short, pale, spiky clusters of hairy projections, thus disguising themselves instead as diminutive Guy Fieris, sent to Brazil to film a special episode of “Diners, Drive-Ins, and Dives.”

“Welcome back to Triple-D! I’m on my way down to Flavortown to score some grub! Haha, get it?!”

“So, that’s it? That’s the big bad caterpillar? Why, I can crush that fuzzy mulch-muncher into a moist smear on the bottom of my boot with no problems whatsoever.”

Yes, but you’d better make sure it’s a boot, and you’d better make sure you throw that boot away when you’re done, making damn sure you don’t touch the bottom of it without thick-ass gloves on.
Lonomia caterpillars’ hazard doesn’t lie in a predatory inclination, or an unpleasant bite like that of the vampire moth. Lonomia is dangerous because of the thick forest of branched spines (called “scoli”) which harbor hollow bristles, each one loaded with its own lovely little dose of venom. These types of defensive hairy structures are common in many types of caterpillar, and many people can get unpleasant and painful skin reactions from touching them and becoming envenomated. But Lonomia‘s special blend of toxins is so devastatingly potent that interactions with this caterpillar, like simply brushing up against it, has lead to human deaths. Yes, this is a caterpillar that can kill you fucking dead.

All species in this genus are highly venomous, but one species in particular, Lonomia obliqua, holds the “honor” of bringing forth the highest frequencies of severe reactions to the venom. Not everyone who accidentally collides with these cryptic caterpillars when moving through the forest (as is typically the way in which the envenomation occurs; when hands and forearms are clearing away brush and inadvertently smack into a feeding Lonomia), but the mechanism by which these perilous pincushions deliver their venom and how this venom does its dark deed remain the same:

The venom is produced within hair-like structures, called “setae”, situated on the scoli. Unlike many other venomous animals, which have a single, definable “venom gland” that secretes and stores the venom, Lonomia, instead, has an array of microscopic vesicles (little sacs) embedded within the cells making up the inside layers of a hollow, tubular tract inside of these bristles. The diabolical cocktail of toxins is slowly secreted from these cells, and pool in this cavity at the base of the tip of the seta. And there it sits. Waiting.

The tip of the bristle, hard and chitinous, is fashioned in such a way that there is a “weak spot”, a pinched line of fragility, near where this internal venom reservoir sits, such that upon just the slightest irritation (like a hand coming along and embedding the toxic needles within the skin), it breaks off like a glass ampule.

From Veiga et al, 2001, showing the end of a seta, equipped with detachable tip and venom chamber.

The tip busts open like a champagne bottle, releasing a lovely, effervescent torrent of horrific toxins right into the bloodstream of whatever poor soul owns that ill-fated hand.

Initially, the stinging sensation from the wound is hardly noticeable, and certainly not something you’d feel the need to stop and inspect what happened, especially if this happened right in the middle of vigorous, sweaty outdoor work. So when the true effects of a particularly bad envenomation start to take place in the coming hours and days following contact with the caterpillar, it may come as an unwelcome surprise to the victim, who may not actually remember getting bit or stung by anything at all.

And what exactly are these effects? Lonomia has a venom with amazingly strong anti-coagulant and anti-fibrolytic properties…meaning that it stops your blood from doing that fairly important function of clotting. If you are unfortunate enough to get a high enough dosage of venom, your blood not only ceases to clot, but your entire circulatory starts…well…leaking. As you might have guessed, when all your internal plumbing suddenly begins to drip like a loose sink pipe, that can be a huge goddamn problem. Envenomated folks can often present with a “hemorrhagic syndrome” called lonomiasis, which most commonly results in widespread bruising in places where your blood is pooling out of your toxin-ravaged circulatory system, making you look like you got worked over real good by an army of angry people with crowbars and bats. All of this happens in nearly complete silence, generally undetectable to the victim in the period of time following the sting. If you are pricked, a great deal of time can pass in complete ignorance of the growing, gushing, collective fount of internal bleeding caused by the venom, causing your organs to marinate in this flood of what should be oxygen-rich juices, disastrously re-routed away from their crucial role in keeping you alive.
In the most extreme cases, this can snowball into brain hemorrhages or renal failure, which of course can precipitate death from catastrophic brain and kidney damage.

Death by caterpillar is not the preferred way to exit this life.

Luckily, about only 2% of those suffering from such Lonomia-related accidents actually perish. Also, on the bright side, the stupendously potent anti-coagulant properties of the toxins found in Lonomia venom have potential medical applications, specifically in the treatment of maladies in which too much clotting is a problem. So, despite the undoubtedly real dangers posed by this moth’s childhood phase, Lonomia might eventually end up indirectly saving far more lives than it has ended.

Moths are fantastic animals, and live far more interesting and dynamic lives than we tend to acknowledge. Whether it’s the unsettling sex-balloons of Chionarctia, the barbaric bite of the vampire moth, the rapacious tyranny of Hawai’i’s most vicious caterpillar, or an insect armed with one of the deadliest touches on Earth, it’s abundantly clear that some moths also certainly possess a unexpected capacity for horror, and command a nervous respect from humankind that they rarely receive.

Image credits: Introductory moth image, Chionarctia nivea, vampire moth, “cute” caterpillar image, Lonomia adult, Lonomia caterpillar, carnivorous caterpillar gifs originally from footage from this BBC Two clip

© Jacob Buehler and “Shit You Didn’t Know About Biology”, 2012-2014. Unauthorized use and/or duplication of this material without express and written permission from this blog’s author and/or owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Jacob Buehler and “Shit You Didn’t Know About Biology” with appropriate and specific direction to the original content.

Eucalyptus regnans, Tallest Tree in the South

I like really tall trees.

I suppose the possession of this adoration of our planet’s living, heaven-raking spires comes as a kind of birthright. I grew up in the Pacific Northwest, an area not only richly coated with swaths of the densest temperate rainforests in the world, but also the tallest forests in the world. I came of age spending a great deal of time hiking and navigating forests largely consisting of several tree species that are among the world’s tallest. Coast redwood (Sequoia sempervirens), douglas-fir (Pseudotsuga menziesii), and Sitka spruce (Picea sitchensis) are all found in the lush coastal forests of Oregon and far Northern California where I spent many long, summer days of my youth; each of them generally regarded as being within the top five tallest tree species on the planet, based on the consistency and frequency of superlatively monstrous individuals within each. Even the “smaller” trees in the region seem to reach uniformly towering heights. Western redcedar (Thuja plicata) can top out at 200 feet (61 m) or more above the soft, spongy soil of the dark, coastal woods of Washington and Oregon. Western hemlock (Tsuga heterophylla), a very common sight in the Pacific Coast Ranges, can easily grow to some 250 feet (76 m) at its droopy crown. The bottom levels of the canopy in a Pacific Northwestern old-growth rainforest can potentially be no less than 150 feet (46 m) high, which is a value not often matched in any other forested region on Earth.

A shaggier version of myself standing with the Quinault Lake Redcedar, the largest western redcedar in the world, on Washington’s Olympic Peninsula in June 2011 (Photo credit: Werner G. Buehler)

It’s no wonder that growing up immersed in this place has left me with a love for these great trees; old-growth forests full of venerable, enormous trees are incomparably majestic places. The sense of perspective and scale that these trees provide is invariably humbling. It’s difficult not to walk alongside them in a kind of hushed reverence, as if you were traversing the floor of an ancient and solemn temple or cathedral, one crafted from humongous, gnarled pillars of wood and moss, rounded with smoothed with deep time and dark silence. The temperate rainforest springs to life in intense bursts of emerald from wherever these trees have embedded their water-ravenous feet, with lithe lances of ferns and the ghostly baubles of root-associating mushrooms erupting wherever soil space is available. These dampest and darkest of woods, blanketed from the sun a football field’s length upwards, have been described as primordial, as a place of senescence and decay, but I think this is a misplaced conceptualization. The sites where the greatest of these trees grow is positively choked with life; life that clings to and parasitizes other life, life that reaches achingly skywards in even the weakest, most diluted sunbeam to touch down on the forest floor. In my mind, these are places of as much birth and flourishing as they are museums.

This aesthetically spell-binding quality, mixed with these forests’ complex ecology and somewhat unique, insular propensity to harbor endemic species…creatures found nowhere else in the world…is what persistently attracts me back to them time and time again (and also inspires me to write about themmultiple times…because I’m a little insufferable).

It is these types of places, misty, verdant groves of titanic conifers, that come to the mind of most when they envision the world’s tallest trees…granted they call the Northern Hemisphere home. It’s somewhat widely known that California’s coast redwoods are the world’s tallest species, and across the North American continent the sheer size of Pacific Northwest forest trees is no secret…especially when compared against the far more “compact” deciduous trees that are common on the Eastern Seaboard. But a very close contender for the title of the most gravity-taunting plant in the world comes from a location not often associated with impenetrable forests. One of the tallest organisms on Earth is an altogether different kind of plant than the behemoth redwoods, and it hails from the opposite side of the globe from the dewy haunts of Cascadia…a place far more associated with rust-colored, alien deserts, blinding heat, and a faunal assemblage that constitutes the world’s largest bucket of shorts-soiling “hell fucking no.”

I’m of course talking about Australia.

Yes, Australia is a place of extremes…where the venom flows like water, the coral reefs are supersized, and summer turns the landmass into a not-so-metaphoric broiling pan of unending solar-powered punishment  (one that keeps getting hotter). From a biological perspective, Australia is a continent perpetually locked in rebellious teenager mode, deviating from the rest of the world’s biota and letting its freak flag fly proudly for millions of years in a parade of pouches, flightless birds, weird plants, fangs, spikes, and scales. It is therefore quite fitting that one of the tallest trees in the world, the only one in the top five that is not a conifer, in pure contrarian style, is Australia’s Eucalyptus regnans…the “mountain ash” or “swamp gum.”

Eucalyptus regnans holds the title of the world’s tallest flowering plant, or “angiosperm” (which is in contrast with the coniferous redwoods, firs, and spruces…which are cone-bearing “gymnosperms”). It is also the tallest tree in the Southern Hemisphere, and the only trees to compete halfway decently for this distinction are other members of the genus Eucalyptus. The only explanation I can think of is nepotism…..
…or, alternatively, that Eucalyptus is a highly diverse group of over 700 species of plants that dominate the Australian flora, with an extensive array of growth forms and habits, and that a giant species or three thrown in is not by itself unusual. Eucalyptus is known for its role as koala chow and its Altoid-scented foliage, as well as a particularly attractive, psychedelic species native to Indonesia and the Phillipines, “rainbow eucalyptus” (Eucalyptus deglupta)…which looks like it was bred by Willy Wonka’s horticulturist.

Seriously, this thing looks like it tastes like a Laffy Taffy.

More broadly, Eucalyptus is a part of a large, wide-ranging family of flowering plants found in the warmer latitudes; Myrtaceae. The family contains a staggering number of species of plants (more than 5600 estimated), including well-known examples like allspice, guava, clove, myrtle, and the enigmatic, endemic (and threatened) ohi’a of the Hawaiian Islands. They are all united in having hard, woody stems and generally having obvious, brushy flowers that strongly resemble exploding fireworks.

This is a variable and successful group of plants, and the stately mountain ash is a jewel in this family’s crown.

It grows in the relatively cool, mountainous, far southern Australian states of Victoria and the island of Tasmania in upper elevations. Mountain ash inhabits the rainy “wet eucalypt” forests that characterize much of the very southern tip of the Great Dividing Range, where it grows at a breakneck rate of roughly one human height every couple of years. The tree grows faster than the mammoth conifers of the Northern Hemisphere, but ends up, in maturity, being a less voluminous, lanky sight to behold; a thin, columnar colossus culminating in a noble tuft of aromatic, evergreen leaves. The mountain ash is to the coast redwood/giant sequoia as Manute Bol is to Andre the Giant. As a pepperoni stick is to a pork chop. As a taquito is to a burrito.
Anyways, you get the point, and I’m going to stop before I make myself hungry.

Some exceptionally altitudinous mountain ash specimens can exceed 300 feet (91 m) in height after as much as four centuries of growth. As of 2014, the largest living mountain ash is the aptly-named (on account of its 100 m (327 foot) height), baronial Centurion, a tree from Tasmania. This sits solidly in the mid-range among the tallest Californian redwoods, but there is an account of a mountain ash from Victoria in the late-1800s near the community of Thorpdale that was measured at about 375 feet (114 m) in height…which would not only put it within mere feet of the tallest reliably recorded tree ever (a coast redwood named Hyperion, at just over 379 feet), but would mean that at the time, it would have been the tallest tree known. The Thorpdale tree was felled more than a century ago, but the site of its former stump remains marked to this day.

“What are these? Cars for ANTS?!” No. Full-sized cars. King-sized forest.

Most eucalypt species have a close relationship with the fires that regularly blaze their way across the dry woodlands and plains that border the vast interior desert of the Australian continent. They have a suite of adaptations that allowed a lineage of plants that, tens of millions of years ago, originated in the region’s rainforests, to survive the aridification of Australia and to prosper over a newer, drier continent: stringy, flammable bark, oil-rich leaves that break down very slowly in the leaf litter, and, commonly, a means of rapidly re-sprouting from fire-protected seeds and/or resilient buds hidden underneath the bark, stimulated to grow after severe damage to outside layers in a bushfire. The majority of eucalypts in these dry, open woodlands are reborn again and again from frequent fires. On hot, dry season days when the sky is roiling with angry, charcoal-colored storm clouds, it is the crack of thunder and lightning that marks their labor pains.

However, the relatively moisture-loving, rainforest-associated mountain ash is a bit of a wuss, comparatively, when it comes to fire. While the species certainly has the dilapidated, vestigial remains of the structures associated with post-fire sprouting from the charred bark, the main strategy appears to reproduce from the seeds left behind following an especially damaging fire (and spectacularly so, with as much as 2.5 million seedlings per hectare (an area about the size of a baseball field) sprouting from seed following a burn…obviously, this is pared back substantially as the trees mature and compete with one another for light and resources in a case of the most cutthroat sibling rivalry conceivable). If the fire is intense enough, the mountain ash often dies outright, never to rise again from the ashes like a Phoenix, save for its genetic torch being carried forward by great multitudes of its progeny.
Mountain ash is superbly adapted to deal with the effects of relatively infrequent fires. It can take a good decade or more after a fiery armageddon for the new crop of young trees to be mature enough to produce seed, so if another super-fire cuts through the area before that point, the entire region becomes effectively deforested of mountain ash. This is obviously a big damn problem, but under normal circumstances, the chances of catastrophic engulfment with earth-cleansing, surface-of-the-sun scale hellfire occurring more than once per decade in the same spot is fairly low.
But…the key word is “normal” in “normal circumstances.”

I linked to a source several paragraphs above that illustrates that Australia is getting hotter as global, human-induced climate change progresses. The other side of that doom-and-gloom coin of the heat being imminently and permanently cranked up to 11 is the fairly solid recent prediction (from CSIRO, Australia’s national science agency) that in the coming decades, rainfall will decline in the range of mountain ash in southern Australia, and severity of drought conditions will increase. Both of these factors contribute heavily to promoting not only more frequent fires, but the types of destructive events that bake the soil into blackened sterility. There are predictions that suggest that the wet, southern, mountain forests of Victoria and Tasmania might not have quite the same jump in overall risk of severe bushfires in response to coming climate change that other regions of the continent will likely endure, but mountain ash habitat will also surely suffer substantial drops in rainfall and an uptick in the amount of that moisture that is evaporated away, sucked right into the unyielding blow drier that is Australia’s future atmosphere.

The seemingly inevitable transition of every single corner of Australia into a fucking tinderbox isn’t a particularly potent threat to mountain ashes all by itself. There’s a second element that comes into play with the relentless dehydration of the continent; one with a very direct human component. Can you guess what it is?

I’ll give you a hint: it rhymes with “blogging.”

Mountain ash is a valuable source of lumber in this part of the world, and, curiously enough, it turns out that threshing the everloving hell out of old-growth stands, and laying immense tracts of forest bare for the timber industry, has lasting, awful ecological effects. The double-whammy threat to these trees comes in the form of the junction between fire susceptibility and timber harvest practices. Mountain ash forests that are 1) younger and 2) fairly homogenously so are pitifully prone to the super-hot, super-aggressive fires Australia has become known for. Until mountain ash grows up to be big, strong, and resilient against the licking of flames, the young trees are as vulnerable to incineration as a box of kerosene-soaked matches at a KISS concert. If these baby-faced whippersnappers are all about the same size/age as well, then there isn’t much diversity, tree to tree, in the forest’s resilience against fire; the fire can spread completely unimpeded due to the absence of burn-slowing bigger individuals.
The most dramatic force shaping mountain ash forests towards a uniform crop of spark-wary sitting ducks is that of unfettered clearcut logging of these trees. What occurs is a tragically tight positive feedback loop that begins to “trap” entire landscapes in a self-perpetuating process of rapid change and potentially irreversible shifting to an entirely different ecosystem structure at the elimination of what once was. Logging promotes the growth of fire-prone mountain ash forests, and the subsequent increased fire activity and severity constricts the ability of that area to allow the re-establishment of old-growth forest…which encourages yet more bushfires in young, dense, regenerating groves of trees.

At this point in time, mountain ash isn’t immediately faced with the dodo’s fate; there’s no indication that the tallest flowering plant in existence will die out in the next couple of decades. As far as we can tell, Eucalyptus regnans is rather “safe” at this moment. However, mountain ash still isn’t specifically protected in Australia, and timber harvest continues largely unabated. The potential threats to mountain ash haven’t yet been evaluated by the IUCN (International Union for Conservation of Nature) as grave enough to warrant the recommendation of protection from exploitation, but there are a couple reasons why we should be concerned with still declining numbers and the health of mature mountain ash forests.

The first of these is that, like other huge, forest-dominating trees like redwoods and sequoias, the mountain ash has a wide-reaching role to play in its ecosystem, and a great many species depend on its presence for their own survival. When you are big enough to influence the entire dynamic progression of the little world that surrounds you, any change or absence has a reverberating, “echo” effect.
The best example of this in mountain ash forests is the stubborn dependence of the Leadbeater’s possum (Gymnobelideus leadbeateri) on the accessibility of a very specific mix of moderately mature eucalyptus trees and wattle (Acacia). This nondescript, nocturnal, squirrel-like marsupial, closely related to the watery-eyed, frenetic, more publicly familiar sugar gliders, is now found only in a tiny stretch of forested uplands in central Victoria. It is a victim of the punctuated, but extensive, loss of mountain ashes old enough to have tree-holes as a daytime refuge (because apparently nocturnal animals aren’t big into the whole good ol’ vitamin sunshine thing); cataclysmic fires in the region, paired with regular clearcutting, have decimated available habitat for the possum in recent years, causing a drop to an estimated 1000 remaining animals in the wild. That may seem like a lot of Leadbeater’s possums left in the world, but in reality, a series of marginally inferno-y summers could evict these little guys off the planet for good. Considering that every single individual alive is now constricted to an area smaller than that of metropolitan L.A., the idea of them getting snuffed out by a bad case of climactic heartburn, or indirectly through a temporary spike in the price of mountain ash timber, doesn’t seem all that ridiculous. If you aren’t yet feeling a bit morose about the possum’s likely eventual, brutal blaze-and-blade initiated gentrification into oblivion, please consider that Gymnobelideus leadbeateri continuously makes a face like you just stole food out of its mouth and told it its birthday was canceled:

Critically endangered? More like critically adorable.

Here, the equation is simple. No mountain ash = no Leadbeater’s possum. No Leadbeater’s possum = no inspiration for a new Pokemon in the next series of games. No new Pokemon = I actually have to grow up and begin behaving like a fully functioning adult human.
This is an unspeakable tragedy.

The other reason the loss of mountain ash forests is worrisome, in particular the old-growth forests full of the largest trees, is that gargantuan trees are uniquely suited for siphoning off the carbon dioxide pollution responsible for global climate change, and converting it back into biomass. Forests, more broadly, are the truthfully important engines on land for grabbing carbon out of the atmosphere and incorporating it into new growth…but for the world’s largest trees (like mountain ash and redwoods), with an increase in size and age, that capacity for transforming greenhouse gases into board feet of lumber climbs in scale almost exponentially. Rather than slowing down and taking it easy on the growth as they enter retirement age, the world’s giant tree species appear to do the opposite, ratcheting up their efficiency as a “carbon sink” and accelerating their carbon mass gain. Big trees, not unlike humans, tend to pack on the pounds faster in their golden years.

Since one big, ancient mountain ash or redwood far more adequately gobbles up greenhouse pollutants year to year than a stand of dozens of smaller, more junior trees, we should start considering the last remaining fragments of old-growth forest, specifically, as a minor means of mitigating some of the output of global carbon dioxide emissions; these exemplary trees are worth saving as both crucial, ecosystem-influencing habitat for scores of other species, as well as a drain on the atmosphere-bound outflow of greenhouse gases. It’s important to note that mountain ash specifically has been shown to have groves that are estimated to be the most carbon-dense in the world, hinting at their potential as especially effective carbon traps. If we lose the biggest mountain ashes, we simultaneously shoot ourselves in the foot a little bit on combating climate change.

Since we now recognize the utility of incredibly large trees as veritable carbon vacuums, we would be wise to understand the scope of what kind of a loss it would be to have these plants fade into extinction. Mountain ash, as a species, seems to be holding on (for now), but the coast redwood was, depressingly, newly included in 2013’s IUCN Red List as an endangered species, still in decline from human harvesting and encroachment.

We are just now starting to understand the most tenuous, subtle relationships between the most massive organisms (among which the mountain ash is a prime example) to ever evolve on Earth, and their surrounding neighbors…both in a direct, ecological framework, and indirectly through recycling climate-altering carbon dioxide. Hastening our pace on keeping the Tallest Trees in the South, or the North, or wherever, from collectively biting the dust at our own misguided and careless hand does far more than save some of the handsome hiking and photography locales we supposedly love so much…it also avoids a world of ecological pain.

Because that’s the thing about really big trees, evidently; the taller they are, the harder they fall.

Image credits: introduction image of E. regnans, rainbow eucalyptusmountain ash with cars, logging photoLeadbeater’s possum

© Jacob Buehler and “Shit You Didn’t Know About Biology”, 2012-2014. Unauthorized use and/or duplication of this material without express and written permission from this blog’s author and/or owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Jacob Buehler and “Shit You Didn’t Know About Biology” with appropriate and specific direction to the original content.

Boxfish: Little Fish, Big Toxins

The boxfish.

Most of the time, I use this blog to blather on and on ceaselessly about all the things about life on this planet I find inescapably fascinating. While all of my exposition on killer fungi, badass birds, weird plants, or whatever obscure, bizarre, horrific, extinct monstrosity wandered into my search history that week is charming (obviously) and fun and all, I don’t often indulge in not only talking about the things that I think need to be shared, but things that are also very directly related to my scientific, academic interests. But, today I shall pander to myself and the relatively narrow realm that constitutes my research interests in the hope that you, dear reader, can push through the voluminous, insatiable outwards expansion of my own ego and acknowledge that my currently proposed study organism for my PhD research, the proud, doughty boxfish…is pretty goshdarned fucking cool.

While I plan on investigating certain nuances about the genetics and evolution of this special group of fishes, the topic of this post isn’t on the subtleties of things like gene flow between populations and speciation, but instead on an incredible, noxious, chemical adaptation that is unique to the boxfish.

But first…what exactly is a boxfish? Boxfish are small fish (between about 5 and 18 inches long, but most are at the low end of that range) that frequent the shallow areas of the warmer parts of the world’s oceans, like coral reefs and seagrass beds. They spend their lives passively pruning algae and small invertebrates like crustaceans, worms, and sponges off rocks and coral with their tiny, delicate mouths. They, as a group, are united in having a body made conspicuously rigid with hexagonal, bony plates fused together to form a hard, yet light-weight shell that encircles their interior, “real” skeletal framework. This shell (which has recently been used as bionic inspiration for automobile design) often has modestly rounded corners, and makes the animal distinctly rectangular in overall shape…hence the “boxfish” name (many species are also referred to as “trunkfish,” and there a some species with preposterously unintimidating horns called “cowfish“). This is an animal that is too hip not to be square.

So, this full-body shell results in the boxfish having a skeleton that essentially looks like a decapitated skull. Similarly to a skull, there are precious few holes in the cage of bone, and the formidable armor only opens up for the eyes, puckered mouth, fins, and tail to peek out into the water. When desiccated corpses of boxfish wash up on beaches, their remains resemble the forgotten, bleached craniums of ill-fated livestock out of a stereotypical, “harsh” cartoon desert.

Photo taken shortly before a tumbleweed rolled into the frame.

Being a living tank confers some benefits. The most obvious of these is that it makes you really damn difficult to eat. Not too many predators jump at the opportunity to slam their pearly whites down on what is effectively the peach pit of the sea. Even for big, powerful, voracious, predatory fish, nomming on boxfishes is less like satisfyingly splintering a hard taco and more like trying to chew a kneecap; it’s a poor decision for all parties involved. Because of this heavy armor, boxfish aren’t exactly the fleetest fish under the waves. Boxfish are only able to propel themselves by using rapid undulations of their itty-bitty fins and exposed tip of their tail, as their entire body has been made inflexible by their bony shell. This is in contrast to most fish, which use strong muscles running the length of their bodies to move their tails side to side, torpedoing their streamlined forms forcefully through the water…and rapidly out of the toothy grasp of whatever is trying to eat them. Boxfish have made an evolutionary tradeoff, sacrificing speed and agility for enhanced defensive capabilities. Also, what they lack in power and evasive skill, they make up for with precision, being able to turn on a dime and dart into secluded overhangs and holes in the reef when pursued as a meal. As someone who has personally sought capture of these little creatures on many occasions, I can attest to their impressive maneuverability, leading to much frustration on my end. Frankly, it’s remarkable how quickly one can go from “aw, look at this cute little guy” to “oh, don’t you run away from me, you miserable son of a bitch” when you need to bag these buggers.

The strategy of hedging your reproductive future on simply being exceedingly unappetizing at the expense of athleticism is not an evolutionary route commonly taken by fish…but boxfish and all their close relatives have turned this approach into an art form. By “close relatives” I mean the order of fish to which boxfish belong, Tetraodontiformes. Tetraodontiform fish, almost without fail, have followed this unconventional path of taking the slow lane while arming themselves with a whole host of tools crafted by evolution to convince everything else in the ocean that, just like a questionably odoriferous bowl of tepid potato salad, they are a meal that just isn’t worth the pain. This coalition of fish, of which boxfish represent a single family (Ostraciidae), are “highly-derived”, meaning, in this case, that they exhibit a high degree of evolutionary modifications that are unique to that group; simply put, tetraodontiform fish are exceptionally, fundamentally different among their finned, gilled brethren. The group, over the course of its tens of millions of years of evolutionary history, has set along a curious trend of relentless reduction of all their fishy features. They’ve lost dorsal fins, many entire bones and portions of their skeleton (just little things…you know, like ribs), simplified their gill coverings, and shrunk their mouths (but kept their jaws big and powerful). They’ve condensed a mouthful of chompers into a handful of hard, strong teeth forming a beak-like shearing apparatus. They’ve even downsized the scope of their genomes (the entirety of the genetic material of an organism), multiple, independent times across several families, and one species, a freshwater pufferfish from Japan, has the smallest vertebrate genome currently known.

This overarching trend of maximum efficiency has been accompanied by not only the development of a wide array of body shapes, perhaps more diverse than any other order of fish, but also an impressively varied range of anti-getting-incorporated-into-the-food-chain measures. Examples abound, and tend to be grouped by family. Boxfish have teeth-unfriendly armor. Porcupinefish can bloat up to two times their original width, often lodging their spiny, spherical selves in the soft craw of whatever tried to choke them down. Triggerfish and their close relatives, filefish, can erect and lock into place sharp dorsal spines that make them very hard to remove from tight spaces within the nooks and crannies of the coral reef. One small family, the molas or ocean sunfishes, are covered in rough, sandpaper-like skin, and grow to such outlandish sizes that few things could tangle with them even if they tried. Pufferfish obviously have the ability to turn themselves into unchewable living balloons, but many species have tissues laced with a toxin so monstrously potent that even the most minuscule amount of exposure is more than enough to leave a human morgue-bound.

Boxfish hail from a line of fishes that are leisurely-swimming, anti-predator toolboxes. Tetraodontiformes, as an order, is a veritable Swiss Army knife of inventive evolutionary gadgetry; a fun-bag of bony plates, spines, levers, inflatable bodies, thick skin, and deadly chemical cocktails.

Adding to the extensive list above is one final trick up the tetraodontiform’s wet, salty sleeve…and it belongs to the fish with angles that’s hard to mangle…the boxfish. Like puffers and some species of porcupinefish, the boxfish is also armed with chemical defenses. It is perhaps no surprise then, that many species of both pufferfish and boxfish sport bright coloration as a passive aggressive warning to would-be diners shopping around the reef for the meal (an evolutionary phenomenon known as “aposematism”, which I outlined in other species very recently). While many species of boxfish are also known for potent differences in the coloration of males and females, both sexes show off conspicuous markings to advertise their toxicity, often consisting of brilliant stripes, reticulations, and spots.

Hey, 1996 called. They want their Rose Art, neon, glow-in-the-dark fuzzy posters back.

So…big deal, right? Lots of things in the ocean are toxic or venomous and have warning coloration; everything from lionfish to sea slugs. What makes boxfish toxicity any different than, say, the toxicity of their close relatives, the pufferfish? The answer comes down to two things; 1) the toxins are completely different and are chemically very unlike almost all other known fish toxins, and 2) the toxins are used in an entirely different way.

Puffers, and most other creatures in the ocean that are endogenously toxic, defend themselves by embedding the compounds in their tissues, right in their very bodies. They saturate themselves with the poison, perhaps taking on a foul taste and/or sickening whatever animals are foolhardy enough to take a bite. But boxfish, when alarmed or actively being eaten, secrete their own toxin in a slimy mucus that oozes from specialized skin cells all over the fish’s body. The clear, toxic snot immediately disperses into the water column, creating an invisible cloud of death surrounding and trailing a very spooked little boxfish.

The force field of chemical ruination unleashed by the boxfish is well-recognized by tropical aquarium hobbyists, many of whom have learned the hard way about the potential consequences of raising these animals alongside other unsuspecting fish. The moment one of Boxie’s tankmates gets little too touchy-feely, the “oh shit danger danger danger!” trigger gets pressed and all hell breaks lose. The boxfish promptly sploogies out a coating of poison goo, and the stuff silently billows out, spreading throughout the tank insidiously and, initially, imperceptibly…..like a fart in an elevator. It isn’t long until the effects of the toxin start choking out just about every susceptible living critter in the vicinity. Under normal conditions, the toxin is released in the vastness of the ocean, with all its currents and fluid mixing, where the toxin eventually is diluted to the point of being functionally benign. But in the tiny, closed system of an aquarium, the lethal excretion becomes trapped in a small volume, creating an aquatic Dutch oven effect. There is no escape from the concentrated, toxin-infused waters, relative exposure continues to climb, and soon everything in the tank that is vulnerable goes belly up, like roaches trapped in a tented, bug bombed house. I’ve personally heard stories from aquarium owners who have come home to a watery, glass graveyard of floating Nemos…and a single boxfish quivering under a ledge of fake coral, hangdog expression betraying its role in that afternoon’s pescicide.

“Rubik! Bad fish! You stay in your rock hole and think about what you’ve done!”

So what is it, exactly, about those nasty, mysterious, skin residues that would allow such a creature to evade predation in the wild…as well as inadvertently nuke an entire tank in captivity, wiping it clean of all complex life? How does this chemical weapon actually do its job?

The secret of how pahutoxin (what we’ve so far identified as the chief toxin in the mucus secretions, also known as “ostracitoxin”) actually moves itself from the surface of the skin, into the water column, and into places on other animals where it manages to screw things up royally, lies in its basic chemistry. Pahutoxin is a type of chemical compound known as a “surfactant.” Without getting into too much detail about how surfactants work at the chemical level, the general gist is that these compounds are often quite good at 1) dispersing in water and 2) making certain things that don’t dissolve in water suddenly very good at dissolving in water. A good example of a surfactant that you and I use (hopefully) every day is soap, or pretty much any other detergent, for that matter. Soap works by way of a number of chemical properties that allow it to make globules (called “micelles”) around the oils in grime and dirt, which normally repel water molecules and do not mix with good ol’ H2O worth a damn. The detergent effect of soaps comes down to the capacity to “cage” microscopic bits of insoluble grossness in tiny bubble-like formations, allowing it to be washed off whatever surface you want with the addition of water.
And just like how running water easily washes away the soap-and-filth slurry from formerly dirty hands, the ocean’s water readily spreads pahutoxin out and away from whatever boxfish is currently shitting its tiny, vibrantly-colored pants, and right into the mug of the hungry, predatory, and now very unlucky pursuer. It’s also worth noting that nothing about the general appearance of the pahutoxin-saturated mucus conceals the fact that it behaves similarly to detergents. I’ve seen on numerous occasions extraordinarily unhappy boxfish pulled out of the water, decorated so heavily with sudsy mucus that they look like they were just scrubbed down with fucking Dawn. It also comes as no surprise to me that while pahutoxin is certainly a unique chemical among fish (as far as we know), it’s thought to behave similarly to a group of toxins described in sea cucumbers, which are, chemically, “saponins”…which are distinctly known for tending to create lots of bubbles and suds.

So, surfactants are specifically good at breaking up things made of oils, fats, and waxes…things that aren’t normally soluble in water. The membranes that make up the barriers that keep the innards of animal cells nice and contained? They’re, conveniently, made out of a bilayer of lipids (a group of molecules that contain fats, waxes, a lot of fat-soluble vitamins, etc.), and are therefore theoretically susceptible to a surfactant’s detergent properties. It was thought for a long time that detergent properties of pahutoxin on the cell membranes themselves was the primary way in which the toxin hurt aspiring attackers. But studies in the last decade or so have hinted at a far more nuanced and complex mechanism of action in pahutoxin, where there may be very specific sites on the gill membrane cells of fish where this toxin binds….sites that are not shared by relatively pahutoxin-resistant boxfish, explaining, in part, the reported, temporary resistance to the toxin’s deleterious effects among boxfish.

And what, exactly, are these effects? They are…well…pernicious, to say the least.
Pahutoxin has an effect that what we would call “hemolytic”, meaning that the toxin tends to pop red blood cells like goddamn water balloons (“hemo” referring to blood, “lysis” referring to rupturing). Given that there seems to be particularly potent effect on the gill tissue of “enemy” fish, a region where there’s a lot of blood vessels and very important exchange of oxygen and carbon dioxide going down, all of which is necessary for a fish to, you know, not immediately die…this makes a lot of sense as a good way to keep big, ravenous fish from doing what they love to do…eat small fish like boxfish. Although pahutoxin appears to have evolved to specifically combat gilled predators like sharks or groupers, adverse effects from the toxin have been reported in mammals in laboratory experiments, and there are reports of severe poisoning in humans who attempted to eat cooked boxfish. But, the main mechanism appears to be one honed by evolution to disperse widely and make its way into the vulnerable gills of an unfortunate meal-seeker, where it promptly takes to exploding life-giving red blood cells left and right, incrementally cutting off oxygen from reaching the rest of the fish’s body. If the attacker can promptly leave this smog of death, it suffers lasting, irreversible effects, but can potentially live. If the predator tries to eat the boxfish, or is trapped in a tank with one releasing its toxins, the pahutoxin’s effects overwhelm the ability to take in oxygen, and before long, the unfortunate creature meets its end at the hands of agonizing asphyxiation…all at a concentration in the water as low as only 10 parts per million. For some visualization on just how impressively potent this is, consider that a concentration of 10 ppm can be reached by squeezing several drops from an eyedropper into a keg of beer. Spitting out a modest swish of mouthwash into a 660,000 gallon, Olympic-size swimming pool also achieves a 10 ppm concentration.

This is the face of a killer.

It’s also possible that boxfish don’t even make the toxin themselves. It’s may be that they “contract” it out to special bacteria that they harbor in the skin cells that make the poisonous mucus. It wouldn’t be all that unusual, considering that they are so closely related to pufferfish, which have shown on numerous occasions, and in multiple types of tissues, that they contain bacteria (most notably Vibrio) which just so happen to manufacture their famously deadly tetrodotoxin (TTX), and are likely the primary source of this toxin in these fish; an amazing symbiosis of “house me in your body, and I’ll help obliterate anything that tries to eat you…I mean “us”, right buddy?”. A species of Vibrio has been found in the mucus-producing cells of at least one species of boxfish, but at this point, it’s not clear whether this toxin, very different from the more famous, and dangerous, TTX, is actually being produced by the bacteria.

Either way, boxfish are remarkable fish, and have…cornered…the market on a particular method of chemically defending themselves. This method, which has more in common with the acrid sprays of landlubbing skunks than with anything fish in our oceans have evolved, is truly unique.
It’s important to note that while we may not yet completely understand how pahutoxin works, we should acknowledge that pollution of our oceans with compounds that chemically mimic the ways in which pahutoxin interacts with cells and specific binding sites…specifically detergent pollutants like soaps, which can accumulate in coral reef habitats from nearby human habitation and subsequent waste runoff…has the potential to disrupt the way these chemicals normally interact. Detergent pollutants in the environment may block receptor sites for pahutoxin…or yet undiscovered surfactant chemicals in our oceans…and restrict the effectiveness of the toxin in a natural, anti-predator setting. If pahutoxin can’t do its job, then that puts boxfish, or other organisms that depend on natively-produced surfactants working like they had evolved to, at a greater risk of increased exploitation by predators, and eventual population decline.

Image credits: introduction image, very colorful boxfish with yellow spots (Ostracion meleagris), hiding boxfish (credit Christie Wilcox), yellow boxfish (Ostracion cubicus)

© Jacob Buehler and “Shit You Didn’t Know About Biology”, 2012-2014. Unauthorized use and/or duplication of this material without express and written permission from this blog’s author and/or owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Jacob Buehler and “Shit You Didn’t Know About Biology” with appropriate and specific direction to the original content.

Angry Birds, Part 2: Sinister Songbirds

While it is relatively easy to think about massive, belligerent, hook-jawed, feathered monstrosities like the giant petrel, skua, and lammergeier as being kin to the long-extinct therapod dinosaurs, creatures solidly employed in the “flesh-rending-death-beast” profession, perhaps a little harder to grasp is the notion that commonplace little tweety birds have the capacity to be pint-size brutes. But there are certainly some shining star examples that I’ll outline here.

When I refer to “tweety birds”, I mean birds of the order Passeriformes, which are known as the “songbirds.” Robins, sparrows, meadowlarks, finches, orioles, crows, swallows, wrens….everything from Big Bird to Woodstock….Red Robin to the Arizona Cardinals…all of them are passeriform birds.
They are members of by far the most diverse order of birds, and with more than 5,000 species, they are among the most speciose of any vertebrate order. They are distinguished from the other groups of birds by, generally speaking, their exquisite control of the syrinx (a vocal organ that is analogous to our own larynx) to generate elaborate bird songs. They are also notable for being a group of animals that has their evolutionary roots placed in a part of the world that is far more frequently noted for having endemic creatures that do not ever leave; Australia and New Guinea. It’s thought that these little guys first broke off from the rest of the flock roughly 50 to 60 million years ago in this arm of the old southern continent of Gondwana (which was isolated then just as it is today) and somehow exploded onto the world stage, rapidly diversifying and eventually finding themselves in all imaginable locations and habitats.

And it is in Australia that the first entry on this list makes its home.

Johnny Two-tone up there (the one who apparently shares an eye-color with Darth Maul) goes by the name of “Australian magpie” (Cracticus tibicen, if you’re nasty), and it’s easy to see why. The black-and-white ensemble (often referred to as a “pied” coloration) and wedge-shaped beak is dead ringer for the magpie bird that many people from the northern continents are familiar with. However, the two birds are not all that closely related, and the pigmentation pattern is a coincidence of convergent evolution. True magpies are in the crow and jay family (Corvidae) and while they are highly-intelligent and mischievous animals, they aren’t particularly aggressive birds, favoring wiley methods of scavenging and hanging around urban and suburban environments for human food waste. In contrast, the Australian “magpie” is a member of the Artamidae family, which is a group of crow-like birds native to the continent and surrounding islands, and the family is far more closely related to other Australasian, Southeast Asian, and Madagascan birds, like vangas and ioras, than they are to the corvids.

It’s also worth mentioning that the genus to which the Australian magpie belongs, Cracticus, is full of birds collectively known as “butcherbirds.”
So, you know we are off to a good start.

Butcherbirds are so named for their unabashed serial killer habit of capturing prey (usually insects and small reptiles) with their sharp beaks, and then shish kebabing the poor little bastards on thorns or sharp branches. They then keep the unfortunate souls there until they are done consuming them…piece by piece. Butcherbirds don’t really have the strong talons that full-sized birds of prey possess, so they can’t really hold down their meals while they tear it to shreds; so, that’s what the skewer is for. It acts as an anchor for them to get some torque when they start incrementally de-limbing the miserably contorted carcasses. These little grand displays of savagery are known as “larders,” and they not only serve as a means of storing food for later, but they also are meant to attract mates. Because nothing gets the lady birds all hot and bothered like fetid corpses of the innocent hung up in your crib like Monet prints.

“Hey girl, I got a big, decaying lizard at my place. It’s a February 2014, great month. Wanna see it?”

This trophy-making bloodsport isn’t specific to one sex, but it’s thought that the larder of the male is potentially the one that is up for judgement. The idea is that if the male can acquire a varied and plentiful collection of flesh decorations, he might also be good at other things *wink wink* *nudge nudge*…meaning of course that he’ll have the capacity to help provide for offspring and pass on decent genetic material…get your minds out of the gutter.

So, after a precursory inspection by the female, some awkward small talk, and maybe a final dose of internal bargaining, if the female is down with it, they settle down and make their own set of chubby-cheeked war criminals.
The two parents feed and care for the young after this, but they often get plenty of help from other closely related birds of the same species in the area. This is that “cooperative breeding” thing I was talking about with skuas in Part 1. It seems to be that in particularly clever species that require a long childhood full of learning and complex behaviorally development, whether they be butcherbirds, crows, chimps, dolphins, or humans, the “it takes a village” mentality is heavily applied to the rearing of youngin’s.
And an extended childhood it is for butcherbirds. The juveniles end up staying with the mother for a very, very long time. Well past the ability to fly and care for themselves do they completely “fail to launch.” Young butcherbirds that are all but full grown and sexually mature tag along with the mother throughout the day, whining at her whenever she catches food so that she’ll give them some, and she obliges, further spoiling the jobless brat.

“Sounds familiar. I have a good-for-nothing man-child…I mean “butcherbird”…at home myself.”

Australian magpies are just a big, lanky versions of a butcherbird. They differ in a few ways, one of which being that they don’t really engage in that whole macabre feng shui shit the other members of the genus are really into.
But they, like other butcherbirds, also have that devotion to parenting on lock down.

In fact, it’s their extremely “passionate” disposition towards caring for and defending their eggs and chicks that have given these birds, already hailing from a clan of vicious mini-raptors, a reputation as one of the more hostile and bellicose birds on the Australian continent.
In the Australian spring, between about late August and the start of October, the season for egg hatching comes around in Australian magpie circles. With this lovely season comes…swooping. Swooping is not a fun dance move. Swooping is not slang for taking an even funner recreational drug. There is nothing enjoyable or cute or happy about swooping.
Swooping is fucking terrifying. Because swooping is when birds make it their goddamned mission to scare and/or maim anything and anyone that dares get too close to the blind, squeaking larvae-like hatchlings…and this is achieved by precision air strikes against the vulnerable skulls of would-be predators. Humans are very much not exempt from being targets of this behavior.

I’ve been swooped before. Not by an Australian magpie, but by a common crow. I was walking towards Amazon Park from the university neighborhood one pleasant, sunny, summer day in Eugene, Oregon, not a care in the world…when I suddenly heard a loud whoosh and felt wingtips clip the side of my ear. A crow had given me an intentionally close buzz, from behind and off to the right. I say “intentionally” because I had no idea it was even there, and if it had been calling at me to stay clear, I wasn’t paying attention; that crow could have easily drilled it’s beak into my crown and I wouldn’t have seen it coming, and I’m very sure it knew that. The close call was more than enough though. After ducking, screaming, and waving my arms above my head for a few seconds, I regrouped and made it obvious to the brainy, angry bugger that was circling around for a second “warning” that I took the hint by jogging another block and a half down the street….keeping my eyes on the ominous black form above that trailed me that entire distance before turning around and flying back to its tree.
After realizing I was out of harm’s way, and cleaning the shit out of my shorts, the experience ended up having a fairly profound effect on how I thought about crows going forward. And I wasn’t even pecked or hit. And it happened only once.

I can’t imagine what Aussies put up with, because once the annual Spring of Discontent rolls around Down Under, Australian magpies take it to the next level. Well, I should say some magpies do. Technically, it’s only the males that do the swooping, and it’s only like one in ten (roughly) that actively engage in the more extreme behaviors. However, Australian magpies are ubiquitous across the continent, and where they are found, they exist in fairly high-densities, where the birds tirelessly defend their territories. They are wonderfully adapted to urban and suburban living as well…so you might, at this point, be getting a sense of why even if only about 5-10% males swoop, if their numbers aren’t hampered dramatically by the entirety of metro Sydney developing on Australian magpie turf…there might be some conflict down the road.

Blue = places where Australian magpies try to kill you,  Pink = places where EVERYTHING ELSE tries to kill you, because Australia

The Australian magpie, now a dutiful new dad, upon noticing an unwitting pedestrian or cyclist intolerably close to the nest usually sends out reasonable warnings. A close approach. A bit of angry chatter. Hopefully, the hapless human isn’t absorbed by their cell phone or MP3 player at the moment, because if the fair warning is not heeded, things escalate really fucking quickly. The Australian magpie does not forgive, and ignorance of the first bit of “communication” is not a valid defense on your end.
The second level of domestic defense involves actual swooping…which means dive-bombing the back of your head at full speed, and then pulling up or to the side with just enough room to gouge and snap at your noggin or ears.
Reason help you if the Australian magpie decides to swoop from the front, because all of the sensitive, important parts of your mug are fair game. That wicked sharp triangle on the front of its head? That’s the business end of a screaming smart missile aimed at the part of your face where your eyes are. That’s what Cracticus tibicen has in store for you.

My Latin’s a little rusty, but I’m pretty sure the “tibicen” means “bringer of pain”

If you happen to share a neighborhood with a few particularly “difficult” Australian magpie bros, your life, for five weeks out of the year, can easily morph into something that would make the ghost of Alfred Hitchcock very, very proud. Your nice, afternoon stroll through Indooroopilly can, at a moment’s notice, be interrupted by a fire-eyed fell-beast, screaming out of the suburban heavens, with a one-track mission to disband your jelly-filled peepers from their sockets and carry them off like olives speared on a cocktail skewer. Understandably, many folks have tried to figure out a way to dissuade the minority of aggro magpies from playing Stabby Stabby with the scalps of the innocent. Some people put sunglasses on the back of their head, because they think the extra pair of eyes will “frighten” the birds and keep them from striking at the skull (not sure why this method is even bothered with, considering that Australian magpies seem to have precisely zero issues with going for the eyes). One common way bicyclists have attempted to deal with swoopings is to attach long, sharp “spines” all over their helmets, the idea being that bristling with anti-bird armament would, er, “persuade” against close approaches. I’m not joking. Aerial barrages from Australian magpies are so damn hazardous to human health that, fully embracing Australia’s Mad Max-ian heritage, people have resorted to running around with goddamned spiked helmets.

Somewhere, Mel Gibson is smiling…but not about this. Probably about something racist.

Sadly, these defensive efforts (which I like to call “hedgehoging”) are largely ineffective against Australian magpies, and quite frankly, your typical “problem” male magpie couldn’t give two dusty fucks about the half-assed arts and crafts project on your head. His genetic legacy rests in the survival of those little, chirping, pink, featherless, scrotum-skin covered lumps of joy back in the nest, and without fearlessness in the face of animals hundreds of times more massive, wearing a Stegosaurus-tail helmet or not, that legacy is far more likely to be cut short. Evolution has crafted a behavior composed 100% out of pure, unadulterated “I-don’t-give-a-fuck”, and there’s not enough pipe-cleaners and fire stokers in the world that can stop it.

Perhaps the most unsettling thing in all of this is that more often than not, a given Australian magpie isn’t indiscriminate in its righteous anger. It’s not like every single person, young or old, male or female, is equally at risk of being assaulted. For whatever reason, nest-defending magpies tend to be a little…bigoted…and bafflingly, randomly so. Maybe the magpie on the corner of Broomfield and Murray spares little old ladies, but festers with a deep, birdy hatred for boys between the ages of 7 and 12. Perhaps the magpie on 33rd and Fig Tree couldn’t care less about middle-aged dudes walking their golden retriever mixes…but 20-something women jogging with their Weimaraners? Oh HELL no. Some burn with unrepentant loathing towards only cyclists, or just the neighborhood mail carrier (referred to in Australia as a “postie,” because that country has an adorable slang nickname for everything).
This specificity of targets among males that do engage in swooping could be random fixation, but the narrow prejudice might have its origins in a form of social learning. The adoption of learned behaviors among individuals in a social group, in particular the wariness of select targets, is something that has been observed in similarly intelligent birds like American crows. In this example, knowledge of the identity of a particular threatening human was disseminated throughout the social network of crows, mimicking the propagation of ideas, stories, and concepts we see in human cultures. This precedent of “education” exists in crows, so it may not be far-fetched to wonder if young Australian magpies are taught what passersby are of primary threat based on the actions of their fathers, and then, following the same vertical, generational transfer of bigotry seen in human society, repeat the same aggressive behaviors (or simple tendencies) once they reach fatherhood themselves.

The abject terror induced on the unluckiest of Aussies is nothing but persistent, and while the onslaught from the skies can be as minor as a heart-jumping nuisance, the danger from these types of attacks has the potential to be truly great. Like I’ve said, swooping Australian magpies routinely aim for the eyes, and people have been blinded before. In fact, eyes are the most frequently affected body part from magpie attacks, being affected in an estimated one-fifth of attacks that cause some sort of injury.
Even more seriously, Australian magpie attacks have even indirectly resulted in human deaths. In 2010, a 12-year old boy died when he ran into traffic desperately trying to evade a swooping magpie, and was struck by a car.
Because of events like this, Australia is a place where there is serious public debate about the line between upholding wildlife conservation and human safety for not only things like “problem” crocodiles…but, as weird as it may sound, “problem” birds as well.
Meanwhile in the U.S., this the closest thing we have to this conversation is typically limited to the occasional snappy dog, or perhaps a bear that keeps wandering a little too close to campgrounds in a National Park.

Australian magpies are certainly not the only songbirds with a twisted, violent streak, and while they are notable for funneling their aggression towards human beings, there are many others that are restricted to simply picking on critters their own size. One group of birds intimately familiar with being the bane of the existence of diminuitive creatures the world over are the shrikes (pictured above).

While there are several groups of unrelated birds called “shrikes,” in this instance I am referring to birds in the family Laniidae; a group of big-headed, robin-sized birds armed with stumpy, formidably hooked beaks that are found primarily in Eurasia and Africa, and far less so in North America. Taxonomically, they are a grouped within the Corvoidea, meaning that birds like crows and birds-of-paradise are among their closest relatives. Most species tend to frequent open, grassy areas, which allows them, like the birds-of-prey they resemble tiny versions of (with comically infantile body proportions), to scan their domain for unwitting prey. They don’t have the grappling-hook talons of actual birds-of-prey, so they utilize components of their environment to get a “handle” on their living, animated prizes, inevitably destined to be of the “culinary” variety. How do they do this? Do they fashion miniature ropes and baskets out of dried grass to restrain their prey? Maybe they collect tree pitch to make their feet all sticky? Aww.

No. They do not do these things. Not even fucking close. Shrikes take the bodies of their comestible conquests and shove them onto a sharp thorn or stick until the entirety of the depth of their little, lifeless (hopefully) figures is inelegantly transfixed in place. Like a toothpick in a cheese cube hors d’oeuvre. But with more blood.
It is in this way that the shrike can capture larger prey, like a small mammal, reptile, or a particularly beefy bug, and hold it in place so that it can incrementally shred it into little chunks with its paring knife of a beak. The act of harpooning large bits of food in this manner, typically in places out of the reach of many other food thieves, also provides a long-term strategy via forming a sustenance cache. If you’ve been reading this entry with any sort of comprehension, the above explanation should sound quite familiar to you. These “larders” are incredibly reminiscent, in both function and appearance, to the grim methods used by Australia’s butcherbirds (described above), and it is perhaps no surprise that shrikes are often referred to as “butcherbirds” themselves. This similar dietary quirk evolved independently in these two groups of birds, miraculously enough, and is a powerful example of convergent evolution, which is often easily observable in physical traits (limb shape, for example), but not typically adequately appreciated in complex behaviors…such as making a larder.
Well…it certainly isn’t appreciated by the mice and lizards that share their home with shrikes, and understandably so.

Mr. Jingles has had better days.

Flitting around and merrily Vlad-the-Impalering every soft-bellied thing in sight, and then greedily saving the spoils for ages later seems like an effective evolutionary strategy all on its own…but it turns out, in at least one instance, there are hidden, unintentionally acquired benefits to engaging in this hectic life of stab-‘n-go.
As you (should) know, not all critters are exactly easy to eat, even when hopelessly cornered or in the grip of their attacker. Some have gargantuan, re-curved claws, married to an on-command adrenaline flood that un-cages otherworldly fury and strength. Some are festooned in venomous barbs and are lit up with more brilliant, psychedelic warning coloration than a Burning Man art installation. Others bloat up like someone shoved a tire pump up their ass, getting so aggressively turgid in their devourer’s craw that they pinch off all incoming lines of life-sustaining oxygen, ensuring that if they are going down, goddamnit if they don’t get some last minute, fatal karmic justice.
And others still are more subtly hard to ingest, at least permanently so, arming their very essence to the gills with powerful cocktails of toxic chemicals, and providing hints to would-be diners through a godawful overall taste and flashy colors…which mean to clue predators in on how they are a worse gastronomic decision than luke warm, gas station sushi. This advertisement of one’s own severely inedible nature is known as an “aposematism”, and is basically an ever-present neon sign reading “do what you want, man, but there are better ways to end your life…I’m just sayin’…”
One of these walking wads of poison is the lubber grasshopper (Romalea guttata), a massive, orange and yellow monster of a grasshopper longer than a man’s finger native to the southeastern United States. As an adult, its wings are too undersized for flight, and it can barely hop worth a shit, and spends its time clumsily fumbling over vegetation, looking more like an inebriated land shrimp than one of its spring-loaded, field-dwelling cousins.

If you are a bird, somehow literate and reading this (I know you’re out there…I’m lookin’ at you, Big Bird), the description of a 3-inch bug, practically crippled by its own damn fatness, probably sent a stream of drool immediately out of your beak. But trust me, lubber grasshoppers work really fucking hard at making themselves as unappetizing as possible.
When confronted with the imminent threat of being unceremoniously inhaled as a mid-afternoon snack, they go into “don’t-eat-me-I’m-actually-really-off-putting-and-gross” mode. The grasshoppers let out a hellacious hiss, spit, and begin to foam with copious amounts of white, toxic foam from pores in their mid-body. The foam itself is bitter to just about every creature that gets a mouthful of it, and typically that’s enough to earn a prompt expulsion from the jaws of death. If the grasshopper is successfully swallowed by a particularly brave and/or desperately hungry predator, the sinister amalgamation of toxins embedded in the body of the grasshopper (high doses of quinones, phenols, and various poisonous compounds derived from the very plants the grasshopper feeds on) all come together as digestion starts, resulting in a vigorous assault on the digestive system of the diner…an animal that is now surely burdened with immediate, stomach-roiling regret. Lubber grasshoppers tend to be swiftly barfed back out before digestion can be completed, and the predator, now shamed and nauseous, will think twice before giving the bulky, tangerine-colored temptations another go.
It is because of their effective chemical defenses that lubber grasshoppers can “afford” to be giant sacks of delicious buggy goodness, propelled by legs too flimsy to evade threats and a brain too chillaxed to give a shit about finding a place to hide. If just about anything tries to eat them, that poor son of a bitch is going to have a really bad time. Lubber grasshoppers are free to bumble around their little world, largely blissfully ignorant of the terrors that haunt their more tasty brethren and lead them to dart between the shadows.

Yeah, yeah, we get it. You’re practically immune to predation. You don’t need to keep showing off.

But, despite the lubber grasshopper’s seemingly air-tight toxic defenses…there remains a loophole…one that the shrike has managed to exploit through simply doing what shrikes do best…sticking bug carcasses on really pointy things.
Lubber grasshoppers are substantially-sized insects, and can definitely fuel a bird like a shrike over the course of a couple of days. If the shrike makes an attempt at consuming any part of its newly-deceased, spike-bound quarry, it reacts like it took a shot of battery acid up the snoot; lots of hilariously adorable head-shaking, spitting the food right back out, and totally avoiding a second taste. However, if the grasshopper larder is left to sit for a day or two, ripening in the summer sun like a head rotting on a Medieval pike…the game totally changes. Apparently, the effectiveness of the lubber grasshopper toxins declines precipitously after death (a property of chemical compounds called “lability”, in which the compound in question, typically a protein, is susceptible to alteration or degradation outside of ideal or in vivo conditions), meaning that the shrikes can then safely consume the grasshopper. They age the grasshoppers on thorns like a fine, crunchy wine, and once they’ve reached the right stage of decomposition, the shrikes feast, enjoying the bountiful reward for their delayed gratification.
This loophole might be enough to lead to evolution of defensive traits in lubber grasshoppers in places where their range overlaps with that of the shrike. If their toxicity is a completely ineffective deterrent to a major predator in their neighborhood, simple chemical defenses may not provide the same level of protection (and contribution to overall fitness), on its own, that it does in places without shrikes. You would expect, given enough time, that in places where this overlap between shrikes and lubber grasshoppers occurs, lubber grasshoppers would, on average, have more effective alternative predator avoidance traits. Maybe they’re quicker, can jump higher, more likely to take shelter away from open areas, less likely to congregate in big groups, etc. There would be greater selective pressure from the presence of shrikes to have more in their defensive “tool box” than just toxins.
It’s like if you lived in a really bad part of town, but felt confident walking around at all hours of the day and night with a truly top-notch bulletproof vest on. It works pretty well, and protects you from the common bullet from time to time, but if one day, a bunch of people start running around with flamethrowers…your key defense is no longer of any use. You better find some fire-retardant clothes or learn how to run faster or your goose is cooked…so to speak. Just like the lubber grasshopper, your carefully constructed master plan is only as good as how universally it applies to all potential threats.

The lubber grasshopper isn’t the only animal to co-opt chemicals from their environment and concentrate them into potent forms for their own use. The strategy is used in multiple groups of insects, including ants, beetles, and butterflies. The oceans are full of examples of toxin adoption as well, either as an evolved tool for defense (specifically known as toxin “sequestration”), or as an accident of diet. Filter-feeding shellfish like clams can easily concentrate dangerously high levels of neurotoxins in their tissues by feeding on microscopic, uni-cellular algae (dinoflagellates), which is why people are strongly cautioned against eating shellfish collected during a “red tide” algal bloom, or immediately following one, since the intake of toxic algae by the shellfish is off the charts during this period. A similar situation can occur in various groups of tropical and sub-tropical predatory fish (most commonly things like barracudas, mahi-mahi, groupers, and moray eels), wherein toxic dinoflagellate algae are consumed indirectly by herbivorous fish, the toxin is concentrated in the tissues of the fish, and numerous herbivorous fish are then eaten by predators, and on and on up through the food chain, with the concentration of toxins ratcheting up exponentially with each trophic level (a process known as “bioaccumulation”), culminating in a kind of potential food poisoning of unwitting fish-eating humans commonly called “ciguatera.” Various kinds of sea slugs take in toxins from their diet, and re-purpose them as an anti-predator defense.
On land, among vertebrates, the most famous example of powerful defensive toxins derived from diet comes from the poison dart frogs of Central and South America (family Dendrobatidae). For many years, it was pretty much accepted that poison dart frogs got their toxins (powerful alkaloids, among the strongest of which is batrachotoxin (BTX)) from external sources found in their native range, since frogs reared in captivity do not end up producing the toxin, and frogs introduced outside of their native range (like Oahu’s Manoa Valley, the wide-bottomed rainforest valley from which I am typing this blog entry at this very moment; a small, introduced population of green and black poison dart frogs (Dendrobates auratus) resides here) do not end up being poisonous either. There were various suspects for the toxins’ origins considered, including merylid beetles and secondarily toxic ants, but in 2007, the primary contributor to diet-derived toxins in poison dart frogs was more or less nailed down as a group of mites. Poison dart frogs take the lubber grasshopper’s strategy of sequestering toxins to a whole other level; among the several most potently toxic species (which are also widely regarded as possibly the most poisonous animals on the planet…so there’s that), a single individual’s skin glistens with enough toxin to put the entire starting lineup of the Seattle Seahawks six feet under. They also have the appropriate levels of warning coloration to match, and the group, generally speaking, are gifted with the most intensely vivid colors in nature found outside of coral reefs.
There are also a very small number of reptiles (snakes in particular) that appear to sequester some toxins from their food (often toxic amphibians like newts and toads), but do not use these compounds to envenomate prey…rather, the toxins become saturated in their bodily tissues. These are in fact actually poisonous snakes, rather than venomous snakes.

But there are another, perhaps unexpected, group of animals outside of the hundreds of insects, scores of fish, piles of amphibians, and the few reptiles with representatives known to take in deadly toxins from their diet and use them for their own benefit. I am, of course, talking about birds.

The fellow photographed above, and looking a bit like the spirit of Halloween incarnate, is a pitohui, specifically a hooded pitohui (Pitohui dichrous).
There are six species of pitohui, and all are exclusively found in the isolated (and threatened) rainforests of New Guinea. They are members of a family of songbirds known as the Pachycephalidae, a group of rainforest birds collectively known as “whistlers” that are commonplace throughout Australasia, many Oceanic islands, and parts of Southeast Asia, and are representatives of an ancient radiation of early songbirds in the region. Even more generally, this family of birds is a part of the proposed clade of Corvoidea…one of four major subdivisions of songbirds, and one that, if you’ll remember from earlier in this entry, curiously, also includes the Australian magpie and the shrike.

As far as rainforest birds go, pitohuis are outwardly unremarkable. They are omnivorous foragers, and don’t have any obvious adaptations that distinguish them from anything else with feathers that flits sporadically between tree branches.
So what’s actually so special about these birds? They are poisonous. Pitohuis are fucking poisonous birds, and just like lubber grasshoppers and poison dart frogs, they steal their toxins from their meals. These toxins, undoubtedly originating from some secondarily toxic insect, are then incorporated into the skin and feathers of the pitohui.

I know some eyebrows might be raised at the mention of a bird without any appreciable violent tendencies filling the final slot on a two-part series on so-called “angry birds”, but hear me out when I say that the position awarded is well-deserved. Just as I characterized the super-scavenger lammergeier as an avatar for the Grim Reaper and as an agent of a more subtle form of darkness, the pitohui’s intrinsic, chemical perniciousness makes its very body the site of a kind of molecular hostility. Pitohuis therefore fill the role of passive aggressiveness within this suite of “angry birds.”

The pitohui’s poisonous plumage wasn’t appreciated by Western science until 1989, when then graduate student John Dumbacher, in New Guinea as a part of a team studying birds-of-paradise, accidentally made the discovery while removing an entangled pitohui from a mist net (a common tool for facilitating the capture/collecting birds in the field). The little guy, understandably, fought for his life while being extracted from the net, and apparently did a number on Dumbacher’s hands with its sharp beak and claws. Upon putting the wounds up to his mouth, Dumbacher found that his lips and tongue began to burn and tingle. Tasting a feather later on led to the same sensation, which lasted for a long while afterwards. It wasn’t until a few years later that the toxin sizzling and sparking on inquisitive scientists’ tongues in New Guinea was identified, remarkably, as batrachotoxin…the same toxin produced by poison dart frogs.
Yes, what would eventually be considered the most striking example of toxin sequestration in birds was initially discovered by scientists sitting in the jungle, licking birds like a goddamn ice cream cone, and wondering what the fuck was making their mouths light up like they just took shots of Pop Rocks and chili powder.

I say “most striking example”, because there are other examples of poisonous birds (albeit precious few), although none of them generate the toxins by themselves, and instead adopt the compounds from dietary sources and concentrate them in their muscles, organs, skin, and feathers.
Among them is a close relative of the pitohuis (found in the same family, also from New Guinea), the little shrikethrush (Colluricincla megarhyncha), which is not a shrike…or a thrush…and only carries the hybrid common name because apparently ornithologists are really, really bad at coming up with original names for birds. Like its close cousins, the nondescript, drab gray little shrikethrush has feathers and skin that are doused in potent, sequestered batrachotoxins.
There is also the blue-capped ifrit (Ifrita kowaldi), a charming, colorful forest bird also native to New Guinea with a common name that is evidently an onomatopoeia of the sound you make when you try to hold in a sneeze…also a bearer of toxin-laden integument, and again, it is batrachotoxin used as the chemical weapon.

There are also a number of other examples of birds that become toxic from their diet, but do not re-route these compounds into their feathers and skin, and rather simply become a noxious meal for a predator, as their meat and viscera are tainted with poison.
Perhaps an example of this phenomenon with the most renown and extensive acknowledgement throughout recorded history is coturnism, a form of food poisoning resulting from eating common quail (Coturnix coturnix), native to parts of Europe, that previously eaten large amounts of toxic plants.
Consumption of various kinds of plants has been proposed as the main culprit for the…er…de-edibilization…of a frumpy, brown bird that looks like it hardly waddle in a straight line, let alone cripple a human with illness by way of its own flesh. Common suspects include henbane, hemlock, or hellebore, all of them toxic to humans.
Coturnism is apparently not a recommended “bucket list” experience to live through. The toxins immediately kick the ever-loving fuck out every muscle in your body in a process called rhabdomyolysis. Simply put, this means that your skeletal muscle, the big ones that help you move around, are partially degraded and destroyed by the toxin. Bands of muscle fibers rapidly deflate and liquefy like an Otter Pop in the summer sun. If the level of rhabdomyolysis is relatively light, your entire body will feel like you spent yesterday doing 14-hours of weight training interspersed with getting hit by a semi-truck or five. If it’s serious, the massive influx of waste in your blood from your dying muscles can cause your piss to turn the color of Dr. Pepper and can even lead to rapid kidney failure. So, there’s that.
The ailment was common enough, and had enough impact, that it pops up throughout recordings from Antiquity, ranging from observations from ancient Greek and Roman naturalists, to anecdotes in the Bible (Numbers 11:31-34) wherein people eat a lot of quail, and end up a lot of dead.

Another example is the Carolina parakeet (Conuropsis carolinensis), a marvelous, golden-headed bird that was once the world’s most northerly ranging parrot species, and graced the skies of America’s plains states, Southeast, and up along the eastern seaboard until freakin’ New York…until it went belly up for good in the early 20th century. It’s extinction was ultimately the result of an anthropogenic twofer; massive amounts of deforestation and habitat loss after European colonization, and the exploitation of the birds for their feathers, which were used to adorn women’s hats in the decades proceeding the demise of the species. Because nothing is more fashionable than irreversible biodiversity loss.
Anyways, these birds were generally considered to have poisonous flesh, and eating them was understood to be a risky endeavor. They were known to be voracious consumers of cocklebur seeds. Cocklebur (Xanthium) seeds are also incredibly toxic to mammals, so the concentrated toxins in the meat of the parakeet proved to be an issue for humans or anything else (like cats, which would routinely die shortly after catching and eating these birds) that tried to get a little taste. The seeds themselves still prove to be an issue, since cocklebur is an invasive plant, and the seeds can certainly harm livestock that accidentally eat them wherever the plant ends up invading.

So, sure, inadvertent concentration of toxins from food sources that happen to be toxic to predators doesn’t necessarily tell an adaptive, evolutionary story in the same way that the sequestering of toxins for specific, alternative use does…as in the pitohuis, ifrits, and shrikethrushes. But why? Why has this trait, seemingly bizarre among birds, this ability to transfer toxins from toxic insects (which got their own toxins from the plants they eat) to skin and integument, evolved in the first place?
In the past, it was assumed that the poisonous feathers and skin were a defense against predators, just as the similarly acquired batrachotoxins in poison dart frog skin were. However, as I’ve outlined above, poisonous animals usually have some means of advertising their unpalatable nature, and this is usually conveyed through intense warning coloration. Hooded pitohuis have the highly-saturated colors typical of aposematism, but the blue-capped ifrit and the shrikethrush are not all that vividly pigmented by bird standards.
It’s also very worth noting that, being nimble forest birds, these creatures don’t live at the same pace typical of animals that use toxins as a deterrent against predators…the lubber grasshopper I wrote about above is a perfect example of how opposite this lifestyle is to that of the known poisonous birds…which, being birds, have the capacity to quickly and efficiently fly the fuck away from danger. You see starkly different predator evasion abilities in toxic animals (or animals with defensive venoms), because these animals don’t need to be agile, or even particularly worried about potentially getting gobbled up. The same tends to go for animals with armored plating or sharp spines; for example, the porcupine does just fine shambling slowly along, since few things are going to bother messing with it anyways. So why would something like the ability to make poisonous feathers evolve in one of the most mobile groups of animals on the planet?

The answer may be that the batrachotoxin in pitohui skin and feathers is an adaptation against parasite infestation. In fact, non-toxic feathers have been shown to be favored over pitohui feathers by lice, implying that the “target” for the toxin isn’t a giant snake, coiled in wait in the rainforest canopy, or a laser-sighted eagle, but potentially the smallest, most nagging micro-predators. But being able to shed oneself of parasites is not a trivial advantage. The cumulative effect of just ectoparasites like ticks, fleas, and lice can sap energy and blood from the host animal, and leave it susceptible to weakness and secondary disease. Living in Hawai’i, I am quite familiar with the effect that parasites and parasite-like insects can have on vulnerable bird species; native birds in these islands have had their populations decimated by the spread of avian malaria, which is transmitted through introduced mosquitoes. The unfortunate ultimate result is an abrupt and jaw-dropping fall in endemic bird diversity in the archipelago over the past couple hundred years. Toxin-laced feathers could certainly be a boon to overall fitness in the face of such potentially far-reaching impacts of parasites and any infectious organisms they harbor.

It’s also thought that we’ve seen some precedent for this before in a fairly different group of animals, this evolutionary strategy of using chemical defenses in the skin, hair, and/or feathers as a means of controlling parasitic infection. In particular, I’m thinking of the slow loris (Nycticebus), a sloth-like primate related to the more familiar lemurs, found across South and Southeast Asia. Slow lorises produce a toxin in glands located in the armpits. This poison, far too strong for even Old Spice to tackle, is activated by saliva when licked, and then groomed into the fur by action of the teeth. The poison is also used in its bite, where the chemical hugs special grooves on the teeth, and in the moment of a hypothetical bite, the slow loris technically has a venomous bite…the only primate known to have one, and one of an incredibly select handful of mammals known to envenomate attackers or prey via the chompers.
It’s worth noting that the populations of ectoparasites inhabitating the fur of slow loris are generally depauperate compared to those of other primates, suggesting that there is some utility of the venom-fur application as an extreme form of bug spray. It is feasible that this anti-parasite strategy evolved independently, using entirely different compounds and toxin acquistion mechanisms, in Pachycephalid birds like pitohuis and shrikethrushes. That tingling, burning, and numbness from the batrachotoxin being absorbed into your hand when you touch a pitohui might be an accidental misdirection from the toxin’s “intended” target…a group of skin-eating, blood-slurping insects smaller than the head of a pin.

“This is the first and last time you touch me, giant, two-legged louse.”

It’s also possible that toxin sequestration, or at least the evolutionary legacy of it, is far more common in some groups of birds than we thought. There is some evidence to suggest that how we understand how pitohuis are related to one another is currently completely inaccurate, and that many of these species actually are representative of several, distinct genetic lineages that place them in wholly different genera within the Corvoidea subgroup of passerine birds, meaning that the pitohuis aren’t a “natural” grouping. It is significantly less likely that toxin sequestration evolved independently several times among “pitohuis” and is more likely that a common ancestor for the group had evolved toxicity, and that Corvoid birds in general, some 700 or more species, either have the capacity to become toxic (assuming some change in diet), or secondarily lost the trait due to evolutionary change, and that the ancestral, “default” condition for this huge grouping of songbirds is one where poisonous feathers are made possible by borrowing toxins right from the food they eat.

So, consider that not only are the shrikes and Australian magpies (both Corvoid birds), mentioned at the beginning of Part 2, soul-crushing, hyperaggressive, feathered projectiles of claws and hatred…but they might be part of a grand family of birds with chemical weapons built right into their goddamned hides, and the ability to exterminate innumerable troublesome, parasitic invaders by simply touching them.
Evolution may have just allowed many of them to “forget” how to utilize the toxins, from a physiological standpoint. This also means that there are potentially many other living Corvoid birds that sequester toxins, but this trait just hasn’t been discovered yet, either due to the assumption that birds do not have poisonous plumage, or because the toxins aren’t anything that humans would notice themselves (like the strong batrachotoxins of the pitohuis).

We share our world with thousands of species of dinosaurs. They might be smaller than the archetypal concept of a proper dinosaur in many of our minds, but despite their beaks and feathers, they are close relatives of the largest, most impressively terrifying land predators in Earth’s history…animals that, no matter their size, where more or less a whirlwind of teeth, claws, rigid bone, and taut muscle.
It should be no surprise that many of the therapod dinosaurs that survived and flourished into the present day would also possess the same unforgiving temper, truculence, and cold-hearted, predatory nastiness that made their extinct relatives so successful for so long. From the puke-prone giant petrels, to the epic, bone-throwing lammergeiers, to the callous, tyrannically surgical shrikes, to the criminally insane skuas, the berserk, paranoid, face-stabbing Australian magpies, and the insidiously deadly, fluffy insulation of the pitohui…the spirit of danger, rage, and appetite for carnage lives on in our modern dinosaurs.

Image credits: Angry grackle intro imagemagpie standing, butcherbirds, mad dad,  Australian magpie distribution map, magpie beak, shrike in tree, shrike with mouse (Marek Szczepanek), lubber grasshopperhooded pitohui in tree, held pitohui

© Jacob Buehler and “Shit You Didn’t Know About Biology”, 2012-2014. Unauthorized use and/or duplication of this material without express and written permission from this blog’s author and/or owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Jacob Buehler and “Shit You Didn’t Know About Biology” with appropriate and specific direction to the original content.

Angry Birds: Part 1, Barbarism from Above

Birds.

These familiar, feathered, fellow Earthlings are often the subject of much adoration from humans, and most birds that enter our daily lives occupy a place of fondness in our hearts. When we think of birds, we imagine, before essentially anything else, their beauty. They are revered across scores of cultures for their complicated and uplifting songs, a trait that exists as the result of meticulous tuning and retouching by sexual selection. Their wind-blown arias range from the simple, structured trill of the western meadowlark, to the complicated, crystal clear chimes of the white-rumped shama, to whatever the hell this insanity is from the superb lyrebird. Many are also regarded physically beautiful, and are gifted with soft elegance in flight, and their frequently vivid feather pigments make them among the most colorful vertebrates outside of a handful of coral reef fish and perhaps poison dart frogs. We equate grace, tranquility, and majesty with birds of varying flavors. Peace with the dove, might and prowess with hawks and eagles….

…the sensation of receiving a prostate exam from Dr. Cactus Fingers…with the potoo

I mean, shit, in Abrahamic and Zoroastrian faith traditions, we even envision angels, the shimmering middle-men of the Creator, as having bird wings plastered on their backs. Lots of things have wings and fly (bats, flies, beetles, and R. Kelly for example) but no, it was the bird’s weird, fluffy, elongated arms that were selected to be associated with a supernatural being that, supposedly, is a distilled amalgamation of all things right in the world.

We also appreciate some species of birds for their intelligence and affection, as well as their impressive capacity for vocal mimicry (I’m looking at you, parrots and mynahs). Many groups of birds are startlingly clever, and corvids (the family to which crows, ravens, rooks, and jays belong) are by-and-large tool-using, highly social, unnervingly observant braniacs that exhibit complex puzzle-solving abilities that make your “whip smart” border collie look like an insipid, drooling dipshit, and are more akin to a ruthless contingent of droogs than to tweety birds.

When we aren’t putting their image on national flags, making our clothing out of their feathers, or pasting them on random knick knacks, we are eating them. Birds are a common source of protein the world over, and here in the States, we appreciate poultry so damned much, that we’ve invented a way to shove as many species of fowl as possible up each other’s asses in order to make a delightful Russian nesting doll of bird flesh. We love the taste of birds so much that we’ve managed to slaughter many species permanently into the past tense. Passenger pigeons used to blacken the skies of North America until European immigrants came along and gave them the good ol’ ‘buffalo treatment’ and straight up blasted them out of their volant swarms with as much pause and contemplation as we give the flipping of a light switch. Humans hunted the flightless red rail of Mauritius to extinction by capitalizing on the birds’ affinity for red-colored objects by pulling out red cloths to lure the poor animals in close…and then bludgeoning them into shrieking oblivion with large sticks.

So, we historically have had sort of a “love/love-to-death” relationship with feathered fauna. It is then, perhaps, not surprising that birds, despite all their charm, can also be somewhat of a nuisance…as some sort of karmic retaliation, I’m sure. A great deal of this comes from their incredibly badass pedigree. It’s important to remember that birds are dinosaurs. Literally. Not kinda, halfway, tangentially related to dinosaurs. Nowadays, the paleontological evidence strongly suggests they ARE therapod dinosaurs, through and through. It’s not so much that Polly is descended directly from T-Rex, but goddamnit if they aren’t kissin’ cousins (a reality that is unavoidably observable in this experiment that aesthetically transforms a lowly chicken into a sickle-toed raptor with ease). Every innocently chittering and whistling thrush and sparrow outside your window is a representative of the last remaining groups of dinosaurs (a clade of critters known as the Maniraptorans), the only group to emerge out the other side of the mass extinction that marked the end of the Cretaceous.

Even after their bigger, toothier relatives kicked the bucket, birds sort of took up the mantel of filling the “giant, menacing, everything-runs-away-from-me monster” niche. In South America, they reigned for tens of millions of years over their ecosystem in the form of flightless, knife-faced homicidal maniacs the size of Shaquille O’Neal (something I wrote briefly about here). One group, the pelagornids, or ‘pseudo-tooth’ birds, went retro and evolved spiky projections from their beaks that basically functioned like teeth. Up until relatively recently in New Zealand, massive, Tolkienesque eagles hunted even larger flightless birds (moas), and likely plucked off the first colonizing Maori like modern hawks take down field mice.

So, given their evolutionary legacy, perhaps it isn’t so shocking that birds, given the right conditions, can be, well, downright unpleasant. I’m a lover of birds (if not solely for the fact that they are, as far as we can tell, motherfucking dinosaurs are you kidding me), but even I can admit that they can be obnoxiously loud (the relentless cooing of the ubiquitous zebra doves on the Hawaiian island I live on is beginning to be an unwelcome wake up call) and foul tempered. Anyone who has spent any time around roosters or overly “friendly” swans knows this. Even as pets they can reek something awful, and then there’s the whole issue of birds shitting as much as your average Royal Caribbean patron. Birds are notorious for spreading disease to people and other animals, and can be agricultural pests as introduced/alien species. But, I suppose that might not be enough horror to transform your conceptualization of birds into that of enraged, dead-eyed, screeching, spray defecating, reptilian nightmares. Especially if your most negative associations with birds just come from getting caught underneath a pigeon releasing its bowel ballast, or from a frustrating bird and pipe-themed app game, which shall go unnamed…

“Up! Up, you stupid piece of shit!”

We know that birds easily have the capacity for bouts of aggression, towards each other, towards other birds, towards their prey, and towards humans. A certain proportion of it is simply overtly aggressive mating; there’s a good chance that whatever “language” mating vocalizations of many species are in, it doesn’t have a word for ‘consent.’ An endangered species of parrot from New Zealand, the kakapo, can be sexually aggressive; and by sexually aggressive, I mean it will mount and dry hump the back of a human’s head. Male dabbling ducks are down-to-their-core gang rapists that possess a shudder-inducingly brobdingnagian, thorny, spring-loaded death dick that looks like it slinky-ed its way out of Tim Burton’s most Freudian, repressed nightmares.

The sins of these dinosaurian, deceptively innocent beings are common and diverse. Obviously, birds-of-prey like hawks, falcons, owls, and eagles are the tigers and wolves of the sky, and rain death upon fuzzy, soft-bodied mammals and clueless reptiles the world over. Vultures chase off other birds from carcasses. Cuckoos are brood parasites that pass off the child-rearing chore onto small, ill-equipped songbirds…which inevitably leads to the slow, pathetic malnourishment of every other chick in the parasitized nest. Corvids routinely bully other birds just for shits and giggles. Just recently, a crow and a seagull (basically, the avian equivalents of a pipe-wrench-wielding Mob leg-breaker)  batterfanged the bejesus out of two hapless doves released by the Pope…to, hilariously, symbolize peace.

You might be aware that the cassowary, a flightless bird closely related to emus, native to northern Australia and Papua New Guinea, has a reputation as a violent animal…prone to defending itself against perceived threats with a casual leaping, roundhouse kick, armed with a razor claw-tipped foot (a behavior that has injured many, and resulted in a single recorded death).

But, the face of badassatry and biker gang ethics in birds isn’t as narrow as bitey swans, prank pulling ravens, and the occasional murderous cassowary. Birds take after their deadly, extinct, dinosaur brethren in more ways than you’d expect, and the reverberations of eons past can be picked up in behavioral and physical attributes across a very wide diversity of these marvelous animals.

The stoic motherfucker above, the one with the icy, blue-eyed stare and unwavering resolve in the face of a snow storm, is the first entry on our list of unappreciated, cantankerous birds; the giant petrel.

While the giant petrel looks very much like a seagull that spent a little too much time reading A Song of Ice and Fire, it is actually a wholly different animal, and genetically and evolutionarily speaking, it belongs to a different taxonomic order of birds. Giant petrels are a part of the Procellariiformes, a group of birds that consists of the most charismatic and well-adapted (and, unfortunately, often times endangered) sea birds on the planet (albatross, shearwaters, petrels, fulmars, etc.). In contrast, gulls are nested within the Charadriiformes, which contains things like plovers, puffins, terns, and snipes (generally considered “shorebirds”). Perhaps predictably, a good rule of thumb to follow is if the bird you are looking at is comfortable being way, way out at sea for long periods of time (in a non-migratory context), it’s more likely to be within the Procellariiformes; if it is ubiquitous along shorelines and inland bodies of water, and not found on far-flung islands in the middle of ocean basins (perhaps with the exception of the tern family)…it’s probably a member of the Charadriiformes instead.

Many of the birds within the Procellariiformes have a tendency to spend an extensive amount of time either feeding or migrating over vast distances of open ocean. Most species are colonial breeders, preferentially seeking out remote islands that are relatively predator-free to nest in massive numbers, and as adults they return to the colonies in which they were hatched year after year for breeding season. While it is thought that navigation back to these colonies relies on astronomical cues, the need for locating nests within these large colonies, and for finding ample food during such long, isolated flights over thousands of miles of open ocean, still exists. The procellariiform solution is found in their exquisite sense of smell.
Procellariiform birds are commonly referred to, collectively, as “tubenoses”; a nickname that refers to the extension of the nasal passages found in this group, forming bony tube (of varying length) that runs along the top of the bill. This is basically like if you had an empty toilet paper roll taped to your nose…but, you know, less stupid looking. This tube likely assists in capturing small particles in the air, and enhances their sense of smell, allowing them to find far-away sources of food on the wing out in the ocean, and potentially their own nest within the congested hustle and bustle of a smelly, shit-encrusted seabird colony. That goofy looking shirt-sleeve nostril is actually their version of Google Maps and Urban Spoon.
Another adaptation to extended time out at sea is the capacity for tubenoses to drink seawater. Yes, these birds engage in a behavior that would surely sicken you or I (or even potentially kill us due to hypernatremia (too much salt in the blood)…to understand the magnitude of the dangerous effect of this condition consider what happens when you pour salt on a slug…that horrific shit is what happens to the hypernatremic brain). Tubenoses are aided by a second installment of evolutionarily-derived gizmos on a head that, apparently, is not that unlike Batman’s utility belt. Tubenoses have the ability to purge salt from the water they drink by use of specially adapted glands at the base of their bill, which, with the help of a number of other organs, re-route sodium chloride from the ingested water away from the blood, and into these glands. The glands then secrete a highly-concentrated salt solution that either dribbles out, or is spectacularly (and grossly) sprayed out. Simply put, tubenoses have the superpower of drinking what is normally toxic levels of seawater because they have little kidneys on their fucking faces.

Many of the larger tubenoses, like albatross and petrels, are superbly adapted to long-distance flight, and have a whole suite of traits that maximize their flight efficiency. The most obvious of these is simply their gargantuan wingspan; long, narrow wings allow for soaring much longer without flapping (unlike short, broad wings (like what is found in many familiar songbirds), which are perfect for maneuverability through dense forest or for evading other, predatory birds…but are shitty for traversing an entire ocean’s breadth, since flapping must occur far more frequently to keep aloft). The side-effect of this is that take-off, and landing, are a bit cumbersome. Most short-winged birds have the luxury of just throwing on the brakes and landing wherever they please. However, the big, bulky albatross, for example, has to engage in long swoops to reduce speed enough so that when they do put down their landing gear (ridiculous, floppy, webbed feet that are poorly equipped for walking, and make albatross terrestrial locomotion charmingly awkward) they don’t strike the earth and tumble beak over tail feather. Just this last weekend, I went out to the Natural Area Reserve for nesting Laysan albatross and wedge-tailed shearwaters at Ka’ena Point on the Hawaiian island I live on, O’ahu, and observed first-hand the challenges of the extremely high-aspect ratio wings of large tubenose birds. More than once, one of the Laysan albatross nesting at the site, made a circuitous, looping cut through the windy tropical air, with wingtips coming within not more than thirty feet of the heads of me and my birding companion. I did not see these birds flap even one time in what seemed like the better part of five minutes as they soared in a great ellipse, eventually finding a deacceleration “sweet-spot” and ending their elegant voyage through the heavens and plopping ungracefully on the hot sand below in what is probably one of the most comically stark contrasts of movement in the entire animal kingdom. Watching this occur, one can’t help but be reminded of the spiraling descent that many large commercial jets make before landing. In terms of airborne agility and ease of take-off and landing, if your backyard robin is a Cessna 172 Skyhawk, then your typical giant albatross is an Airbus A380.
In addition to the simple mechanical efficiency afforded by immense, thin wings (wings that are long enough to make the wandering albatross, Diomedea exulans, owner of the largest wingspan of all modern birds, occasionally reaching 12 feet across), the largest tubenoses also have a little trick that makes it even easier to fly without the slightest bit of effort. Some species have a special tendon that actually locks the wing into place once fully extended, so that the wing can stay in that position for hours at a time. You know that little spring catch that keeps an umbrella in the “open” configuration? These birds basically have that technology incorporated into their wing musculature.

So, it can be said that the Procellariiformes, with their Doomsday Prepper-esque self-contained fluid filtration system, built-in Garmin and cruise control, and wings that catch the trades far more effectively than any sail, are part of faction of seafaring birds that make even the hardest, crustiest, beardiest, veteran sea captain look like a quakey-legged, queasy landlubber.

“Aye, everything I am…’tis a lie.”

It is within this already hardy contingent of open-ocean avian gods that the giant petrels (two species of bird within the genus Macronectes) find their relations. These birds, divided into a Northern and Southern species (although both are native to the coastline of Antarctica, and the islands surrounding it) are most closely related to the fulmars, and are, unsurprisingly, a part of the petrel family, Procellariidae. They are the most massive tubenoses with the exception of the regal albatrosses, both of them reaching about the size of an eagle. Outwardly, they don’t appear to be much different than their relatives; muted coloration, large and powerful wings, a hooked beak made up of the nine plates unique to the Procellariiformes, webbed feet, etc. If you were to take a fulmar and beef it up in size a few fold, you’d, at least on the exterior, get a giant petrel.

But the giant petrel has a secret that separates it dramatically from the rest of it’s tubenose kin, a secret buried beneath a deceitful outer visage that makes it appear more as a docile dabbler of the ocean surface (albeit a big and noisy one), rather than the agent of darkness that it actually is. Tubenoses have a diet based upon marine foraging, in which they consume squid, krill and other crustaceans, fish, and occasionally plankton. This is a pretty standard menu among most seabirds and shorebirds. However, somewhere along the line, giant petrels lost their refined taste for sashimi and cocktail shrimp. Giant petrels, instead, primarily fill their bellies with the decayed flesh of beached marine mammals, and fluffy, helpless penguins (sometimes, as this very graphic video illustrates, hollowing out the poor penguin’s body cavity like it was an intestine-filled piñata…while it is still very much alive). Giant petrels are the Antarctic’s answer to vultures, and they take up their ecological role as the cold southern sea’s clean up crew with enthusiasm, beating out all smaller scavengers at whatever felled beast rots on the barren shores of the antipolar continent, diving claw-tipped beak first into the fetid, blubbery jackpot.

Hasn’t given a single fuck in over one million years

And by “enthusiasm” I mean “aggressiveness”…and by “aggressiveness” I mean “pretty sure someone slipped these birds some bath salts.” Giant petrels lay waste to any poor, opportunistic seabird trying to capitalize on the good fortune of a fresh, bloated seal carcass. They are aided by their substantial size advantage over any shorebirds within their home ranges, their strong and sharp bill, and their relatively strong legs (in comparison to their tubenose relatives) that allow them to bear down on their quarry, living or dead, with ease on land. When arriving at a carcass, they adopt a posture designed to make everything with feathers in the vicinity to pack up and get the fuck out; wings arched and outstretched, neck extended with the hooked beak directly facing any contenders, and tail stiffly pointed upwards (an “intimidating” posture I’ve seen similarly employed in testosterone and alcohol-soaked college-age human males). If their “carrion master” pose doesn’t adequately impress, they drop the diplomacy act right quick and get on with beating the everloving shit out of everything around them until they get their way (again…this is something I’ve seen in the wilds of the house-party-full-of-20-year-old-dudes ecosystem).
If undisturbed, they plunge right in, and the formerly intact dead body is torn apart like it was a free pizza thrown to a pit of graduate students (haha, the joke is that we are poor). Apparently evolution didn’t have the foresight to gift these fledgling scavengers the bare neck and face of the vulture, so their feathers on their faces quickly become drenched and sticky with blood and offal. This doesn’t slow them down at all, apparently, because they will run around with this shit plastered all over them like they just waltzed out of the finale of “Carrie”…ravenously waiting to pounce on the next unsuspecting little penguin, or unclaimed corpse on the shoreline.

“You like this color? I think the shade is called ‘screamoglobin’.”

So, obviously, once giant petrels have a meal, they definitely don’t disguise their role as the main purveyors of violence on the Antarctic coast. And violent they are. I’ve already alluded to their impassioned vivisection of penguins, an easy task for them considering that penguins are basically just squishy, clumsily toddling bags of meat. But, they regularly have a go at taking other prey as well, out of necessity. There aren’t a lot of options for blood-thirsty animals like giant petrels in the Antarctic; it’s not like there are a glut of different types of prey animals running around for them to pick from. The great, frigid south is an isolated land without much else than animals that either fly there or swim there, meaning that most everything on the coastline is either a bird or a seal.
Adult seals, especially the gargantuan leopard and southern elephant seals (which can reach weights of 1,300 lbs and 5 tons, respectively), are obviously far too big for a giant petrel to eat (although I wouldn’t put it past these one of these assholes to try). But seal pups? Yeah, those are barely big enough to leave leftovers. It isn’t that uncommon for a group of these soulless bastards to descend upon a seal pup the minute it’s been separated from its parent.
Giant petrels are actually very adept at slaughtering the babies of other animals. They dispatch penguin and albatross chicks with remorseless ease, and just as often as they make the adults their entree of choice. Yes, they even snuff their own close relatives, the albatrosses, and devour them in an act of appalling taxonomic treason.
One thing is certain, if it is cute and defenseless, giant petrels will desire to rend it into tiny, bite-size pieces.

It’s also worth noting that stuff comes out of giant petrel mouths about as often as stuff goes in….because giant petrels are quite fond of vomiting. I should clarify that this isn’t referring to the sweet, altruistic, maternal regurgitation that a great many birds use to feed their chicks. No, giant petrels engage in projectile puking, a la The Exorcist, on a fucking horrifying scale. So, emetophobes beware.
This typically occurs in two distinct types of scenarios. The first is related to the birds’ fondness of food. Being opportunistic foragers, giant petrels tend to eat as much of whatever it is they claim (or slay) as possible, because there’s no guarantee that there will be another meal around the corner…something I can identify with as a graduate student. “Modest portion size” is not a part of their lexicon. They are such, er, “healthy eaters” that early European explorers to the Southern Ocean used to call them “gluttons,” a name probably further supported by the giant petrel’s habit of loitering around sailing vessels, endlessly lusting for food scraps from sailors. Sometimes, these feathered Mr. Creosotes gorge themselves to the point where they are too heavy for take-off. If a human, or anything else that can be considered a predator (something that doesn’t exactly abound in the Antarctic, for much the same reason as why there isn’t much variation in prey…isolation), gives them a spook, they’ll promptly throw their digestive tract on ‘reverse’ and expeditiously shoot a slurry of seal pancreas out all over the ice. Once they are back to their svelte selves, they can muster the strength to take to the air and evade whatever threat forced them to toss their cookies. This is a strategy used by pythons, boas, and me when I accidentally try to jog right after going out for Taco Tuesday.

The other context for this lovely behavior of assertive upchucking comes from a very different place. You see, giant petrels, as well as many other procellariiform birds, have weaponized their barf.
Well, more technically speaking, it’s stomach oil, rather than the partially digested contents of its most recent meal. Stomach oil is a mixture of primarily wax esters (a fatty acid) and triglycerides (major constituent of animal fat and vegetable oil) that is very energy-rich, and is stored not in the stomach itself, but in the proventriculus, which is the first ‘chamber’ of the digestive system of birds, and is sandwiched between the esophagus and gizzard. The oil is a by-product of regular digestion, and most tubenoses make the stuff. It’s thought that it has a role in energy storage for long-distance travel, but it has a far more interesting utility as “get-the-fuck-away-from-me juice.”
Giant petrels are notorious for spraying this crap at would-be attackers, including both predators and combative, rival giant petrels. It isn’t corrosive, like an acid or strong base, but it is still a potently effective chemical weapon. For mammals (including humans), the stomach oil’s revolting stench is its main deterrent. The experience is a bit like getting a cup of rancid salad dressing, two-week old bacon grease, and decomposed escolar splashed right in your face. Since the oil is well…oil…it doesn’t exactly wash out easily with water, so if you are lucky enough to showered with this liquid offering, your clothes will probably be stuck with the nauseating miasma for a very long time. This nasty, skunk-like defense mechanism is also the origin of the giant petrel’s second old-school nickname from maritime explorer times; the “stinker.”
If you are a fellow bird and you get oiled, the consequences can actually be a little more serious. Stomach oil, once cooled by the outside air, solidifies into a waxy product that ends up gluing feathers into matted clumps…and, again, it doesn’t readily dissolve in seawater. Anyone who remembers the tragic effects of the Exxon Valdez oil spill (or the far more recent Deepwater Horizon spill) can recall what happens to seabirds when their feathers are dowsed in sticky, heavy, oily substances.

So, yes, giant petrels aren’t exactly a bunch of charmers. Despite the fact that their goofy, webbed feet make them look like they should be trying to sell you payroll deduction insurance, these birds would certainly make their vicious, extinct, therapod cousins proud.
The Antarctic is inhabited by a creature that is infamous for callously abusing the vulnerable and powerless, habitual greed, a consistently repellent demeanor, and for spouting copious amounts of loathsome filth out of its mouth. And no, I’m not talking about Rush Limbaugh.
The next time you are tempted to schedule a little idyllic excursion to Terra Australis to have a life-changing, grand ol’ time marching with the fucking penguins…remember this princely, dainty beast:

“SCREEEEEEEEEE”

There is another antagonistic avian that frequents the frozen, polar regions of our planet, but unlike the giant petrel, it can be found near both the South and North Poles (but nowhere in-between). It gravitates to the cold, harsh lands and seas, far from the warm embrace of direct sunlight, and perhaps, on a certain symbolic level, appropriately so, given that this creature has a soul as icy and brutal as the places it inhabits.
It is allied closely with the gulls (within the Lari subdivision of the aforementioned shorebird order, Charadriiformes), but it forms its own family (Stercorariidae) within the order. Perhaps even more notably, of the seven species of this group of birds, all of them reside within a single genus (Stercorarius), which is impressive considering that the ranges of some of these apparently closely related species are separated by many thousands of miles. It’s appearance betrays its close relation to the seagulls. It basically looks like a burly, brown gull that’s been excessively hardened by a life scraping out existence on the edge of Earth’s zone of habitability, and with the addition of a beak that looks to be crafted out of scalpel-sharp obsidian, it becomes clear that this bird is doing a bit more than leisurely picking at abandoned fast food in a beach park dumpster.

Stercorarius are common sights both along the coastlines and inland areas of both poles. They are, as I will explain in detail shortly, ecologically important, crafty, and efficient predators in the wilds of high-latitude nations like Russia, Canada, the Alaskan U.S., the British Isles, Scandinavia, Chile, Argentina, and New Zealand (as well as various small island chains and isolated isles in the Arctic and Southern Oceans, sometimes in great numbers). Since they range over such a diversity of nations and human cultures, and are invariably imposing, unforgettable birds, it’s no surprise that they are granted unique names that distinguish them from other shorebirds. In Anglophone areas of the Arctic (Canada, U.K., the U.S.), they are commonly referred to as “jaegers”, which is derived from the German word “Jäger”, which translates to “hunter.” Yes, this is a bird which has a name (notably originating from the tongue of a Teutonic barbarian tribe) that has been associated with 30-story tall robots that beat the piss out of giant, alien sea monsters and a liver-melting liquor that tastes like cough-medicine, bad decisions, and the tears of vanquished foes…so, yes, we are off to an epic start. In Norway, it is known as the “storjo.” In parts of Scotland, the “bonxie.” In the far south of Chile, “págalo.” The Māori of New Zealand (Aotearoa) refer to them as “hakoakoa.” The Japanese know it as “Touzoku-kamome.” However, it is the name it was given by the Faroese (the indigenous Germanic peoples of an island chain between Scotland and Iceland, the Faroe Islands) that has the most usage worldwide; “skúgvur.” This name has subsequently been corrupted to “skua”…not to be confused with “ska”, which is altogether different. For example, the piercing, ear-shredding screech of the skua is far more tolerable than ska.

Skuas also have less brass. Less stupid hats, too. ….I really don’t like ska.

Why does this one group of gull-like birds get their own brand in every language? Sure, they are big, powerful, muscular birds, but they aren’t particularly distinctive in that regard. Most species have dull coloration and plain features. What makes them important enough to be considered appreciably distinct by these high-altitude cultures?
Many times this is because a certain animal has some sort of cultural significance, and it would be reasonable to wonder if the skua holds a special place of reverence in these cultures, reflected by the language. Perhaps they have some sort of role to play in the local mythos. Are they viewed as messengers of changing times, for good or bad? Are there parables about them? Do they represent guardians, or perhaps cosmic villains? Or is their strong, direct flight in the face of biting polar winds something to be admired, and therefore noted? Why has the skua repeatedly carved out a unique spot in the communal psyche of all these cultures, out of a wide diversity of fellow smelly, squawking seabirds?
The answer is that it has less to do with any sort of noble trait that is worth emulating or aspiring to…and more to do with the fact that skuas are, by bird standards, belligerent, unapologetic, hyper-aggressive, inherently amoral assholes. Basically, whenever it came time to name all the birds in each of these areas, it’s almost a guarantee that upon watching the skua for a few hours, whoever had the task of doing so wrote down the following footnote for this nefarious beast: “Note: Easily identifiable by how much of a bag of dicks it is to all the other animals.”

“I heard u were talkin’ shit.”

So, why the bad reputation? Why does this bird get the same amount of esteem as a run-of-the-mill dog fight coordinator? Why does this bird, apparently, deserve its own “Scumbag Skua” internet meme?

Well, most skuas are, at least part of the time, “kleptoparasites.” To get an idea of what kleptoparasitism is consider the following scenario:
You go into work in the morning, and deposit a perfectly crafted sandwich in the break room fridge, storing it there until lunch. You spent a lot of time piecing this masterpiece together, and you are really damn proud of your creation. Gracefully folded slices of glistening, peppered pastrami, an entire garden of exquisitely prepared, fresh veggies, crisp pickles, muted swiss cheese, a healthy splash of stone-ground brown mustard, and you even added a bit of expensive tangy mayo you picked up at the local mom and pop grocer. You wince at even the thought of calling it a “sandwich”; this is glory between two soft, rich, slices of rye.
You’ve wrapped it neatly in paper (never in a goddamn Ziploc bag, that kind of egregiously unsophisticated bullshit would never even occur to you) to let it breathe, and you’ve clearly marked it with your full name in vibrant, cobalt Sharpie ink. Your mouth waters at your desk for a full four hours as you try to work over your rising hunger, your bubbling, painful anticipation. Just when the olfactory siren song that’s been looping in your brain ever since you got that first whiff of your culinary opus currently marinating in the coolness of the company refrigerator becomes unbearable, your lunch hour arrives and you briskly walk back to the break room. You are euphoric. Your hands are quaking, and your stomach is wailing and sending great thunderous bellows throughout your body…but you are elated that your patience has paid off. At long last, you can take part in the gastronomically perfect experience waiting just beyond those dingy refrigerator doors.
You open the fridge, alabaster light blinding you like the brilliant glow of Heaven itself. Your smile falls, the life drains from your eyes and your heart rockets to the bottom of you, and your hunger blackens into bilious despair. Where is it? Dead space on the rack where you placed it. Is this real? You pinch yourself, hoping that you are in a nightmare. No, the welt on your skin confirms your unfortunate reality and you slip into a frantic rage, slamming the door and scouring all surfaces of the room. Maybe someone moved it and forgot to put it back, you delude yourself, eyes tearing, breath rapid and shallow. Your gaze moves to the trash can and you drop to your knees, clasping the thin plastic edges as you will yourself to peer inside.
You cry out. The once carefully, intricately folded paper is in there, carelessly crumpled and empty of its precious contents, wedged in the bottom in a violated ball. The rye crumbs decorating it may as well be blood. You slump back on your heels, catatonic. Defeat. Treachery.
You’ve been sidelined by the demoralizing club of betrayal…one brandished by a very special type of person. That person? That sociopathic wad of ambulatory after-birth that plundered your lunch and lanced your very soul? That was a kleptoparasite.

A kleptoparasite is an animal that gets by, at least part of the time, by stealing prey from other predators…either by force, or by conniving thievery…as in the sandwich example. The term literally means “parasite by way of stealing”, where the Greek prefix ‘kleptes’ means ‘thief.’ A kleptoparasite is one who engages in unrepentant food looting, at any cost, and skuas are archetypal examples of those that uphold this, er, lifestyle choice.

Skuas are tenacious and fearless thieves, and don’t appear to have any qualms about barreling face first into an animal holding a fresh kill, all sharp beak and wings and shrill screaming. More often than not, this is enough to get the poor animal (almost invariably another predatory bird) to drop its prize, which can be a small mammal, another bird, or most often, a fish. Size of the target is also not much of an issue, which is astounding, considering that while skuas are big as far as shorebirds go, they often take on animals that are several times their mass; in the Arctic this can be a large eagle or a heron, and in the Antarctic this can be the oh-so lovely, blood-soaked, vomiting dynamo that is the giant petrel I described above. One well-placed hammering of an eagle’s scythe-shaped beak, or one oil bath from an ornery giant petrel, could ruin a skua’s week and/or potentially kill it. But the skua has…moxie…and goes right the fuck in there anyways…and on a regular basis, wins. This is sort of the equivalent of someone attempting to rob a bank, which happens to be filled with a dozen armed police officers, by barging in completely in the nude, screaming into a megaphone, and proceeding to wildly slap everyone in the vicinity…and somehow coming out not only alive, but with armfuls of Benjamins.
Skuas really don’t seem to care, and even if the situation is too hopelessly dangerous to take on headfirst by themselves, they’ll sit back and wait for an opportunity…or simply gather more of their criminal friends so they can organize an “Italian Job” style raid later. Threat of crippling injury and excruciating death be damned.
Skuas truly are the honey badgers of the bird world.

While many times the target is a something as simple as a seagull or a tern innocently trying to hork down a few herring, they will sometimes congregate around a seal or whale carcass…which inevitably results in tense showdowns over the spoils between other species of unscrupulous scavenging animals. I find it splendidly dinosaurian.

I fail to see any difference between these two images.

When skuas aren’t harassing and bullying everything around the polar schoolyard trying to score an easy meal, they are shrewd, opportunistic predators…more than capable of killing for themselves if they need to. Much of the time, their diet consists of small to medium-sized fish, and a smaller complex of species in the Arctic (the ones most commonly referred to as jaegers) are partial to feeding upon small mammals like lemmings. However, they will routinely attack adult penguins, which are many, many times their size…but not to kill and eat them. You see, adult penguins, during certain parts of the year, hide tasty, vulnerable morsels that a skua can more than handle. I’m talking about penguin eggs and tiny, fuzzy penguin chicks, both which are protected by the skin flaps around the feet of the comparatively gigantic parent. All the skua needs to do is distract the adult with repeated stabbing with its spur-shaped beak, and it can root in underneath and dislodge the helpless egg or baby with lightning fast precision.
It’s like the story of David and Goliath…if David nonchalantly gulped down Goliath’s infant children as effortlessly as Kobayashi inhales hotdogs.
Nothing is safe. When a skua is around, there’s a good chance someone is going to die. Cute puffins? Pathetically one-sided aerial dogfight ends predictably violently. Dead. Oystercatcher, minding its own business? Head dashed against rocks. Also dead. One of those coveted penguin eggs? Over-easy. Full grown sheep? Fuck them too.
The skua, cold, calculating, exceptionally bright, and not squeamish about brutally taking what it desires, would have been a fine pet choice for Gordon Gekko. This bird, this depraved, deadly amalgamation of seagull, hyena, and butterfly knife, has a moral compass so twisted and rusty it’d make any serial killer blush.

“That’s a nice baby penguin you got there. It’d be a shame if something were to…happen…to it.”

But, the skua does manage to consciously spare one being from its sadistic bloodshed…its own progeny. Yes, the only thing that isn’t subjected to intimidation and violence from these delinquents are young skuas and skua eggs. Their vicious habits don’t extend into cannibalism (although the young chicks typically have a Spartan upbringing, which ends up resulting in fratricide in the nest…so yeah, they start off with the murdering in the cradle), which I suppose is to be expected.
For their eggs and young, skuas channel the unbridled machinery of their malevolence towards an aggressive defense of the nest, where they unflinchingly dive-bomb anything that strays too close (including humans). So, you know, there are no baby showers at the Stercorarius residence.
This strategy of recklessly swooping at everything that moves, with all the paranoia of a meth-head renting a space below a guy who watches Cops really loudly, is sometimes combined with a behavior unique to some populations of skua that may potentially be a boon to fitness. In some populations of the brown skua, Stercorarius lonnbergi, off the coast of New Zealand in an island chain known as the Chatham Islands, the mating system of choice is of the cooperative variety. That is, specifically speaking, polyandry; in which one lady bird is paired with two or more gentleman birds. This setup occurs in other bird species from time to time, but almost always in really stable, terrestrial, non-migratory species that experience very high population density. Shorebirds and seabirds are almost unfailingly monogamous, so this breeding behavior in these specific populations of skuas is a bit unprecedented. We don’t yet understand if this reverse harem situation is conferring some sort of special evolutionary benefit to skuas residing in this specific island chain, or why this breeding system developed in the first place.
One thing is certain; despite the skua’s off-putting veneer of blood-lust, carnage, and unfeeling, surgical dismemberment of baby animals…deep down, they have a soft spot for their kids. I find it appropriate that a bird that makes a living exploiting, extorting, manipulating, and terrorizing everything around them would, through their strong parental defense and support of offspring, accurately emulate the multi-generational organization of a crime family.

The third entry in this list is one that lives about as far away from a marine environment as possible; up in the highest plateaus and mountains of Eurasia and Africa. It is a “proper” bird of prey (meaning that it belongs the order containing familiar raptors like hawks and eagles, Accipitriformes), and maybe it might seem like a cop out to include something that has more conventionally T-Rex-like behavior (i.e. flaying lesser beasts with its claws and face) considering this list is supposed to honor the weird, obscure, and surprising…but I think you’ll be able to see why I’ve made an exception in this case.

Why’s that? Well, this bird, known to many as the bearded vulture, or lammergeier (Gypaetus barbatus, to the ornithologist crowd), looks like a goddamned for-real dragon.

Pretty sure this resplendent fucker flew straight out of a Dethklok music video.

Smaug up there is actually just a vulture in name only, and is actually not that closely related to the naked-headed incarnations of vulturedom most of us are familiar with. It’s closest relative is another “vulture” from various parts of the old world (Neophron percnopterus, sometimes known as the “Pharaoh’s chicken” or, more commonly, the Eqyptian vulture), and together, these two species, alone in their respective genera, are thought to form a unique subfamily (Gypaetinae) within the greater hawk/eagle/vulture/buzzard family (Accipitridae). Lammergeiers are exceptionally uncommon, but, as a species, they don’t seem to be threatened with extinction (although there are some localized threats). Instead, their scarcity is likely a natural consequence of their truly expansive home ranges throughout mountainous territory that generally doesn’t have the food resources available to support large, dense populations of bearded vultures anyways.

…not that there should ever be any reason to doubt the lammergeier’s resilience in the face of humanity because LOOK AT IT. Seriously, this thing doesn’t even look mortal, let alone even remotely concerned with the meddling of us ground-tethered peasants. The lammergeier does seem almost entirely separated from the goings on of the rest of the animal kingdom, since it casually hangs out further up in the mountains than even the trees can grow. These heights can be 16,000 feet or more above sea level; far enough up that most humans can’t even get enough oxygen into their bodies to maintain normal physiological status…which generally includes not hallucinating, puking everywhere, and bleeding from your eyes and nose. Not only does it thrive in places that are inaccessible to humans primarily because they are that much closer to the vacuum of outer goddamn space, but it’s been known to hang out near the summit of Mt. Everest. Yes, this bird makes the highest peak on the planet, the global “Mt. Olympus”, its playground.

In addition to the apparently borderline divine character enveloping the lammergeier, is its general aesthetic embodiment of the hyper-masculine, coke-fueled fantasy themes surrounding performances and album art of metal bands of the early 1980s…an element I very much appreciate about this animal. The lammergeier looks like a literal god of rock and roll, birthed from the strings of the very first electric guitar…a being, once summoned, that arrives by ripping through the heavens, propelled purely by 170 decibels of space-time splitting vocal belt, a trail of blow and pyrotechnics in its wake, with eyes bloodshot from the strain of being so awesome. I mean for Christ’s sake, even its name, “lammergeier”, sounds like a damn Rammstein album name. This is less of a bird, and more of fire-eyed wyvern, aloft on great wings, slicing through craggy canyons and scaling glaciated mountain passes, while lightning strikes and alights the roofs of mountain cottages aflame in time with a vociferous bass line.

Somewhere, the ghost of Ronnie James Dio is creaming his jeans.

Oh, and it has a beard…because of course it does.

Surely, you say, such a powerful and otherworldly thing must be a force that instills widespread fear among all animals in the uplands of the Old World. How many metric tons of yak does it consume weekly? Have the Nords of Skyrim learned how to quell its anger by use of archaic, magic incantations? Does it burninate the countryside annually, or just during election years? Do goats sacrifice themselves when a dark shadow passes overhead?
These questions, which I am 100% sure you are asking yourself, are fair…but despite its appearance, there is a good reason it is known as a “vulture”, and that reason is its primarily scavenging lifestyle. A bit of confusion comes in when you examine the German translation behind the other common name, “lammergeier”; it means “lamb-hawk”, and is based upon the old, erroneous, belief that these birds are sheep slayers. It does occasionally take live prey, but it gets most of its nutrition from the deceased.
Before you fold your arms over your chest and pout about your rapidly diminishing opinion of real-life Roc that you preemptively thought palmed horses like a basketball and caused avalanches with its devilish screams, and chalk up this bird to being nothing more than a hermit eagle that has a hairstyle that makes it resemble a cooler version of a Thatcher-era Rod Stewart…know that the manner in which the lammergeier scavenges is like no other vertebrate on Earth.

When a large animal perishes in the wild, vultures are the stereotypical “early birds” to the site of the rotting carcass. They track down the meal by way of both keen eyesight and smell, and in no time are ripping into the bloated bag of goodies. With the aid of scavenging mammals, insects, and additional bacteria decomposition, the dead animal is stripped of flesh/organs/everything in no time, leaving a dry, sun-bleached skeleton. To most animals, and certainly to most birds, at this point in the scavenging/decomposition timeline, the skeleton is a fairly useless food item. It’s caloric capacity has been completely extinguished.
But none of these rules apply to the lammergeier, because the lammergeier eats bones. Not bone marrow; that succulent treasure inside large bones is a treat held in high regard by a wide variety of animals. No, the lammergeier eats bones. Sure, there’s marrow attached to it, but the bones are swallowed right along with it. Straight up.

Consumption of bones as a major form of sustenance isn’t exactly common in nature. Meat and skin and offal are all far easier to digest, easier to get to, and very nutritive…bones are far less so for all of these things. Specialization in eating something as…rugged…as bones is, unsurprisingly, an uncommon evolutionary and dietary strategy when there’s so much muscle to glean from. Why eat the “stick” of the drumstick?
There are few organisms that prefer the hard stuff, and one notable example are the bone-boring worms (Osedax) that mow down on whale skeletons once they sink to the dark floor of the ocean. There is a single type of fly, the bone-skipper, which up until last year was considered extinct for the better part of a century and a half, that eerily mimics the lammergeier’s preference for bodies in late decay…although it doesn’t necessary eat the bone matrix itself, and instead breeds and lays eggs within the marrow of pre-broken bones. But these examples are both invertebrates, and osteophagy (bone eating) doesn’t really occur in vertebrates outside of the occasional herbivorous mammal supplementing its diet with the minerals from bones. The lammergeier’s making its livelihood primarily off of bone consumption is a unique one among birds, most assuredly.

So, how does it accomplish this? The first step is to make sure the bone is in manageable pieces. The lammergeier is strong enough to break and crush smaller pieces of bone it acquires with its beak, but for larger bones like the femus and the pelvis, more drastic measures must be taken.
These “drastic measures” include gripping a substantially sized bone in the talons, potentially weighing as much as the bird itself, and flying off with it. The bird makes a direct flight to a spot directly several hundred feet above a collection of particularly hard and jagged rocks, where it lets go of the bone, leaving gravity to do the work of splintering the bone into shards that can be easily swallowed. I like to call this the “Newton method,” and it’s something that other birds (like crows) have done with hard nuts and snail shells on hard rocks or asphalt surfaces.
The lammergeier then swoops down, checks out to see if it was successful, and if so, gobbles up the best pieces and surveys its territory for additional bones.
It’s because of this behavior that one of its oldest names is the “ossifrage”, which means “breaker of bones.” In Arab cultures, it was once called “al-kasir”, which roughly translates to “shatterer” or “breaker.”
I have a hard time conceiving of a more badass series of names for an animal that looks as Herculean as the lammergeier.

Notably, this species uses the exact same method to dispatch living tortoises. The same system is used to smash the turtles’ shells, allowing easy access to everything inside. Supposedly, the ancient Greek playright, Aeschylus, was killed when he was struck in the head by a fucking tortoise falling out of the sky in the year 456 B.C. According to the story, the tortoise was dropped by an “eagle” that apparently thought the shiny top of Aeschylus’s head was the perfect place to cleave the reptile in two. Given the known habit of tortoise tossing by lammergeier’s, it’s possible that this species was actually the “eagle.”
Or, alternatively, someone just made up all that shit.

If you sat down and tried to eat several handfuls of bone shards and marrow, assuming you wouldn’t choke on their descent through your puny, non-lammergeier-esophagus-of-steel, you would end up having a bad time. That would be a one-way ticket to a night in the Painsville emergency room. Human stomachs, and the stomachs of a great many other vertebrates, aren’t up to the task of digesting bone even remotely close to completely.
However, the lammergeier has a second trick. Not up its sleeve, but deep in its stomach. The lammergeier has remarkably strong stomach acid. I’m talking xenomorph blood strong, and this highly-concentrated, acidic environment in the stomach much more quickly dissolves both bone and the marrow inside than anything you are I could muster from our own inadequate digestive chemistries.
For some context, human stomach acid is a hydrochloric acid solution that hovers around pH 1.5. This is about the acidity of lemon juice, maybe a bit stronger. Lammergeier stomach acid has a pH of half that, meaning that the concentration of acid in the bird’s stomach is an order of magnitude higher, and approximates the corrosive nature of battery acid.
Basically, if a lammergeier were to projectile vomit all over you giant petrel-style, the stomach acid would take the finish off your face like you were a Nazi taking a peek at the Ark of the Covenant.

If you still aren’t convinced that the lammergeier is the most ludicrously hardcore bird to honor our planet in the modern era, get a load of how these animals go about making baby bone-destroyers.
Lammergeiers relinquish their hold on their stately, solitary lifestyle cruising between cliffs, scanning their world for woefully unsmashed bones, for one thing only; to…well, bone, so to speak. And it is a sight to behold. Apparently, when two such supernaturally awesome creatures come into close contact with one another, the fabric of the universe that binds basic physics together breaks down. The meeting of complementary lammergeiers for the purpose of copulation is like breaking the speed of light….the consequences are breathtaking and a little terrifying.
The courtship display begins (presumably after deafening, introductory mating calls made up of nothing but brain liquefying guitar solos and thunderclaps) with the lammergeiers meeting in mid-air. This followed by a spiraling, acrobatic dance a thousand feet above the rocks below, full of free-fall plummets back down to earth, talons locked together, only to separate at the last possible moment and start over again. The performance, full of unfathomable g-forces, in-flight engaging and disengaging, resembles a season-ending, frenetic fight scene in Dragonball Z, not foreplay. Hills crumble. Storm clouds gather. Zeus himself watches from on high and weeps, in awe…and to be honest, a little bit of arousal.
Eventually, the deed is done, and another one or two kings or queens of the Ceiling of the World are hatched the coming months.

So, the lammergeier may not be a flame-spitting feathered serpent summoned directly out of a Tenacious D song, but it certainly looks the part. Lammergeier are, in actuality, not particularly aggressive (they don’t even really make noises, let alone battle with other organisms)…but only because they never need to be.
They are the solemn, patient tail-end of the scavenging train in their ecosystem. They have no interest in the chaos of devouring viscera that their bare-headed cousins engage in. They are content to wait until the skeleton’s riches go unappreciated. Lammergeiers aren’t ‘angry birds’ in that sense, in the way of the skua and the giant petrel. But they hold a symbolic role in their world that I find significantly more chilling:
Other scavengers, the crows, griffon vultures, jackals, maggots, beetles, hyenas, etc., remove everything but the framework of the animal, the scaffolding, the internal structure that the skeleton provides. Without the lammergeier, these would slowly be corroded by high-altitude wind and sun, bleaching and powderizing over hundreds of years, perhaps even fossilizing. The lammergeier steps in and acts as a force of nature, blazing through eons of environmental erosion within the caustic chamber of its own gullet. It is in this sense that the lammergeier fully breaks down the remains of the animal, even the last, hard leftovers, and actually forms, directly, the last link in the circle of life. The last link that returns the deceased animal’s carbon, nitrogen, and amino acids right back into the earth.
It is in this way, this inescapable finality that this bird provides, that the lammergeier is the most appropriate avatar to associate with Death.

Other scavengers clean up the mess. The lammergeier brings them Home.

Image credits:shoebill intro image,potoo,sea captain,giant petrel in snow, giant petrel eating seal, bloody giant petrel (Laurent Demongin), bloody giant petrel (face) (Laurent Demongin), skua in flight, skua face, skua and penguins, skuas and giant petrel, dinosaur showdown paleoart credit to: “Thunder Across the Delta”, Mark Hallett (1996), lammergeier, lammergeier in flight

© Jacob Buehler and “Shit You Didn’t Know About Biology”, 2012-2014. Unauthorized use and/or duplication of this material without express and written permission from this blog’s author and/or owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Jacob Buehler and “Shit You Didn’t Know About Biology” with appropriate and specific direction to the original content.

 

Arachnids: Pseudoscorpions

Pseudoscorpions.

It probably does little to assuage the unsavory first impressions one has with the subject of the third group featured in this blog’s arachnid series, the pseudoscorpion, by noting that its name literally means “false scorpion.” Perhaps this is no surprise, given that without the proper context, pseudoscorpions are intimidating both in their name and in their generally “icky” appearance, armed with menacing claws, attached to a body that resembles a lightbulb made out of alligator skin. If nothing else, you’d at least be somewhat justified in being suspicious of them. Looks like a scorpion, has “scorpion” right in the name, but isn’t a real scorpion? Please. Just what is that tailless son of a bitch hiding? Maybe you doubt that there is such an animal, and the photo above simply depicts a normal scorpion, sans its stinging tail, removed by Photoshop. “What kind of rube do you take me for, blogger on the Internet?! I do not take kindly to unprovoked trickery!”, you howl, with language curiously more sophisticated than what is normal for someone so enraged.

The thing is, pseudoscorpions really are a unique group of arachnids distinct from “true scorpions.” They are partitioned off from the rest of the arachnids in their own taxonomic order, the predictably-named Pseudoscorpionida (also called Chelonethida). It is thought that in the Great Arachnid Family Tree, pseudoscorpions represent one of several springy arms forking off from a massive branch known as Dromopoda, which also includes potential sister groups like harvestmen (think daddy longlegs), “actual” scorpions (the nasty, pinchy, venomous kind), and solifugids (the infamous “camel spiders” of Internet renown, the subject of urban legends stemming from U.S. soldiers’ alleged interactions with them during the Iraq War…and a tasty snack for Bear Grylls). There is some disagreement within the scientific community about the Dromopoda division, and whether or not it is a true, monophyletic group (monophyletic meaning that it’s a defined grouping on a tree including a species and all of its descendants; for example, the grouping of “reptiles” excludes mammals and birds, and would exhibit something known as paraphyly…however “amniotes” includes ALL the descendants of the amniote common ancestor (birds, lizards, mammals, snakes, turtles, etc.) and would constitute a legitimate, monophyletic taxon), but even if Dromopoda isn’t a cohesive evolutionary unit, it is still likely that pseudoscorpions, based on a combination of morphological and molecular characters, are closely allied, evolutionarily, with many of those “Dromopodan” orders.
So yes, pseudoscorpions are kissing cousins with desert-terrorizing nightmares like scorpions and camel spiders, and those gangly, spider-lookin’ things that collect as corpses in the lonely corners of your garage every summer.

Unlike with the other previously featured, underappreciated arachnid orders, hooded tickspiders and tailless whip scorpions, the reason pseudoscorpions aren’t that familiar to most folks doesn’t have origins in low species diversity, overall rarity, or being restricted to remote habitats in the wilds of the tropical zone. Pseudoscorpionida sports more than 3,000 species in over 400 genera…which is a shit load. Furthermore, additional species are being recorded all the goddamned time; one species was recently discovered right smack in the middle of arguably the busiest and boot-trampled National Park in the U.S., Yosemite National Park. Another was found lurking in a cave system in the Colorado Rockies, like some kind of tiny, lobster-clawed Gollum.
Their range is ridiculously expansive, with pseudoscorpions being described from frigid mountaintops and the Canadian north, to the equatorial jungles, to small, isolated island chains, to even, apparently, under the fucking ground. They seem to show up pretty much everywhere outside of Antarctica, which is a biogeographic trait held in common with not much else outside of bacteria…and humans.
So, what is it? If there are so many of them, and they are supposedly EVERYWHERE, why don’t we see them all the time? Why do we not have pseudoscorpions pouring into the seams of doorjams when the bite of winter descends, like we do with spiders and other domestic arthropods? Why don’t we spy them in the city park alongside butterflies and ants?

Quite frankly, a huge part of the answer is that pseudoscorpions are uniformly Lilliputian. This is in contrast with true scorpions, which have representatives that can weigh as much as a hamster. The largest species of pseudoscorpion flirt with a centimeter in length, but most species are about as long as a dime is thick. These guys could theoretically, comfortably use one of the wrinkles on your thumb knuckle as a cozy blanket. That’s right, pseudoscorpions, the Joe Pescis of the arachnid world, are wee little fuckers, hardly discernible with the naked eye. Because of this, only incredibly close observation outdoors, or a chance encounter with one crawling across an unnaturally light surface (like a painted, indoor wall), will yield an interaction with these strange arachnids.

Pseudoscorpions fairly conservatively follow the standard arachnid bauplan (four pairs of legs, two main body segments, pedipalps, chelicerae, etc.) and while most folks would describe them as “basically a scorpion without the tail”, I think they look like someone took a termite and a crab and smashed them together, end to end.

Just don’t expect this guy to sing “Under the Sea”

It’s probably those crab-like pincers that are the stand-out characteristic of the pseudoscorpion. They are modified pedipalps, the same leg-like appendages that gave rise to true scorpion pincers, the spiked, raptorial arms of the amblypygids, and the simple “feelers” of spiders. These pincers, and accompanying pedipalp “arms”, are often incredibly large in proportion to the rest of the body. While their primary purpose is to pin down and immobilize prey, which consists of arthopods even smaller than themselves, these pint-sized pliers are also instrumental in getting the pseudoscorpion from place to place. Pseudoscorpions are arachnids, and do not have sensory antennae to help them navigate their environment like insects and other arthropods do; an element of life that is not assisted by the fact that pseudoscorpions, regular inhabitants of Earth’s less-than-illuminated places, have very poor eyesight, and many species are flat out blind. However, the pedipalp pincers help fill that sensory role. Most species’ pedipalps (in addition to various other areas on their bodies) are covered in long bristles (called “trichobothria”) that are highly sensitive to minute disturbances and vibrations in the air, acting like a battery of some sort of fine-tuned aerial seismographs, and help give the pseudoscorpion an idea of what the hell is in front of it, behind it, and all around it with amazing acuity. So, when a pseudoscorpion moves along, pedipalps extended far in front, these appendages act like a combination of a white cane and a Nifty Nabber.

The other, more obvious role, of the pedipalp pincers deviates away from the “touchy-feely” and into the realm of the “slicey-crunchy”. Make no mistake, pseudoscorpions are brutal predators, and will mercilessly slaughter whatever tender, defenseless critter that they decide is food (see: just about everything small enough). To us, a pseudoscorpion can be flung off a desk with not much more than a heavy sigh, but in the world of the very tiny, pseudoscorpions possess all the formidability of a Bengal tiger. If a wayward mite, ant, or larvae finds itself hopelessly stuck in the path of a hungry pseudoscorpion, their options are limited to a) defecating in abject terror and/or b) hastily praying to whatever god arthropods pray to that they are spared a slow death.
Such pleading for divine compassion would be fruitless, however. Death at the scissor-like hands of a pseudoscorpion is an agonizing experience for the captured prey animal. The first step the pseudoscorpion takes in slaying its meal has its roots in the anatomy of its pincers. Like a lobster’s claw, the pincer is divided into a stationary half and a mobile half, the latter of which does the actual clamping action. The mobile claw contains a venom gland and duct that runs to the pointed tip. When prey is captured in the pedipalp, the venom is promptly injected into the poor soul’s innards. This venom isn’t designed to necessarily kill the animal, just to get it to stop its pathetic struggling. Once the prey ceases trying, in vain, to escape, it is pulled towards the mouth and gnashing chelicerae, where a saliva-like fluid full of corrosive enzymes is slobbered all over its immobilized, but still very alive, body. To get an idea of what that’d be like in our big, macroscopic world, imagine a cougar attacking a deer (or human) by shooting it with a fast-acting tranquilizer dart, and then casually vomiting industrial-strength lye all over it. Lovely.

“Come on, who wants a hug?”

This World’s Grisliest Act of Digestion takes place all over the globe, in many different varieties of habitats. Like I’ve previously noted, pseudoscorpions are master colonizers, having some kind of presence on just about every major and minor landmass other than Antarctica. The sun never sets on their empire, even if to us, it’s practically invisible. They are found in all the stereotypical arachnid places; wedged under tree bark or rocks, ambling around in leaf litter or soil, crouching in subterranean hollows, and even in the intertidal zone, nimbly moving around barnacles and mussels in their search for food at low tide.
They are most commonly encountered by humans indoors, and usually within the pages of an old, dusty book. On it’s face, such a fact seems a bit ludicrous. In books? Why? Pseudoscorpions can’t even fucking read.

“Oh, hey man. Don’t mind me. Just finishing up some Hemingway.

It’s thought that the “cover to cover” ecosystem is particularly attractive to pseudoscorpions due to the abundance of booklice (primitive insects of the order Psocoptera) living within the ancient, neglected tomes. Booklice, wingless, tiny, and slow, are sitting ducks in the wake of a hungry, claw-bound pseudoscorpion. Chances are, the pages of that old copy of Across Five Aprils in your bookshelf that your grandfather gave you are the site of both literary and literal bloodbaths, the inner spine festooned with enumerable, nearly microscopic, petrified carcasses of booklice, evidence of many past meals left behind by pseudoscorpions. Because booklice cause significant damage to old books, the presence of predators like pseudoscorpions routinely crawling in and culling the herd is pretty beneficial to any bibliophilic human.
Pseudoscorpions also dine on other troublesome indoor pests, like mites, and the larvae of carpet beetles and clothes moths. By doing this, pseudoscorpions assist us in working to eradicate economically disruptive animals that are out of our reach, by being too elusive or simply too small. Screw calling the Orkin man, just let a few thousand pseudoscorpions loose in your home and call ‘er good.

How is that these itty bitty critters manage to get everywhere on the planet, nevermind into every nook and cranny of your house? They can’t fly or swim across oceans, and are limited to not much more than clumsily and blindly scanning the dirt for prey.
The secret lies in a habit of theirs called “phoresy.” Phoresy is when an animal attaches itself to another, larger animal purely for transportation. This happens a lot with other arthropods. Mites, for example, will bum a ride from place to place on much larger insects like flies or beetles. In the case of pseudoscorpions, flies and beetles are also typically used, as well as mammals. The process is pretty straight forward. A large flying insect lands nearby, and before it can take off again, the pseudoscorpion slyly edges close, clasps onto a leg, antennae, or undercarriage of the body with its mighty claws, and prepares for takeoff. The little guys manage to hang on for dear life while being propelled through the air at what is, for them, speeds comparable to a cruising commercial airliner. The intrepid voyagers eventually, either by choice, or by accidental loss of grip, skydive from their six-legged taxi into what is hopefully greener pastures, with bountiful resources.
Pseudoscorpions essentially turn any comparatively big, highly-mobile animal into an unwitting chauffeur, allowing them to glean rides across vast bodies of water and mountain ranges (or accidentally into our homes). It’s possible this ability of pseudoscorpions to stick up a claw along a fly-packed strip of tree branch, and hitchhike to places traditionally far out of their reach, is at least partially responsible for their extremely widespread distribution.

“Alright, I’m on. Let’s Christopher McCandless the fuck outta here.”

Some species can take this non-consensual carpooling to extreme levels. One example is tropical pseudoscorpions native to Central and South America that associate with rotting components of fig trees. These pseudoscorpions (as colorfully outlined in Dr. Olivia Judson’s book Dr. Tatiana’s Sex Advice to All Creation) escape the dearth of food and mate resources in their decaying, wooden home by hitching a ride on newly adult harlequin beetles (Acrocinus longimanus), emerging from the wood below. The phoretic fate of pseudoscorpions traveling this way is, on one hand, fairly traditional, with a main objective being the ultimate arrival at fresh logs with lots of food and shelter. However, since as many as two dozen pseudoscorpions, of both sexes, can stow away on the back of a gargantuan, bulky, harlequin beetle, the brief road trip can serve a second function; procreation.
The crowded, sweaty cargo hold of an airborne harlequin beetle quickly transitions from uncomfortable, stuffy ordeal in coach, to a sexy, co-ed, party bus type of situation. The pseudoscorpions waste little time on introductions and get straight to the boning, undoubtedly much to the chagrin of their poor beetle host, which has no other choice but to wait out twenty-some inconsiderate assholes engaging in an orgy in the inaccessible, impossible-to-scrub pocket under the wings.
To get an idea of the perspective of the harlequin beetle in all of this, imagine rolling out of bed, getting into your SUV to go off to work, and as soon as you start the engine and put it into drive, a throng of horny teenagers stream out of the bushes by your driveway, and aggressively force themselves into your vehicle, where they promptly begin to disrobe and fuck like there’s no tomorrow. Any pleas for them to stop are completely ineffectual, so you do your best to concentrate on the road and drive on. Oh, and you just so happen to have the pleasure of an hour long commute to work.
Pity the harlequin beetle, completely without dignity; the first few moments of its adult life spent smothered by the sex lives of other creatures.

While in this particular case, pseudoscorpion sex can seem free-spirited, haphazard, and anonymous, without much courtship or consideration behind mating choices, this isn’t the case for most members of the order. Pseudoscorpion reproduction tends to be somewhat complicated, with many species employing elaborate mating rituals. Some species mate in a manner similar to hooded tickspiders (examined in the previous entry in this arachnid series), in which a spermatophore, after careful and delicate positioning by the male, is forcibly splattered in the female’s gonopore.
In some species of pseudoscorpion, the male produces a stalked spermatophore that fastens to the ground. Then, through a complex “mating dance”, the male leads (and by “leads”, I mean “drags”) a targeted female closer and closer to where the spermatophore has been deposited. Eventually, after much insincere gallantry on the part of the male, she is positioned over the spermatophore, it is deposited inside of her, and bingo, the deed is done.

“Come on, goddamnit. Closer…closer….clooooser…”

Pseudoscorpions are the benign neighbors you’ve never heard about, dutifully hunting down indoor pests behind the scenes throughout the warmer months (and just calmly waiting out the winter by sealing themselves up in stasis inside a silken cocoon). They are to be respected for this reason, being of a unique class of arthropod predators that get rid of the things that irritate us, and yet have no capacity for harming us. Even a few representatives of their relatives, the spiders, also viewed as economically and ecologically beneficial, are very able, and willing, to hurt us. With pseudoscorpions, it’s a win-win for us.
That being said, these odd dwarves of the arachnid world, are inarguably sociopathic moochers. They remorselessly latch onto other hapless animals for free transportation (and NEVER pay for gas), they copulate wherever they please without any consideration of restraint, and the males have, at best, coercive sexual behaviors. Actually, that description sounds disturbingly similar to acquaintances from my college years…
Anyways, pseudoscorpions are harmless to humans, and provide a net benefit in our day to day lives. But from the point of view of just about anything with antennae and an exoskeleton, these manipulative, Napoleonic pricks are a scourge, “blessed” with talents in all realms of douchebaggery and general dickishness. Whether it’s a venomous pincer suddenly lancing your body cavity, or the drone of an obnoxiously condescending lecture inspired by a year spent vacationing in the pages of Kant’s “Critique of Pure Reason”, pseudoscorpions are a pain in the ass of a great many of the littler members of the animal kingdom.

Image credits: Introductory image, 2nd pseudoscorpion, 3rd pseudoscorpion, pseudoscorpion in book, phoretic pseudoscorpion on fly, dancers

© Jacob Buehler and “Shit You Didn’t Know About Biology”, 2012-2013. Unauthorized use and/or duplication of this material without express and written permission from this blog’s author and/or owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Jacob Buehler and “Shit You Didn’t Know About Biology” with appropriate and specific direction to the original content.

Electric fishes

Electricity.

It’s hard to imagine modern life without the stuff. It heats, cools, and lights up our homes and businesses, reduces the chaos of transportation, and because it powers technologies that allow for communication across vast geographic areas, it is the lifeblood of the Information Age. Over time, we’ve discovered that the utility of electricity is ludicrously diverse; from keeping food cold enough to prolong preservation, to saving lives through defibrillation of the heart, to being a dick to your friends. The fact that I am currently writing this on a laptop computer, and then disseminating the information in it over the medium of the Internet, is an undeniable consequence of humankind’s harnessing of electrical energy.

If you are inclined to think of the control and use of electrical energy as a human “invention”, then prepare to set your anthropocentrism…and perhaps yarns telling of curious, bespectacled statesmen armed with kites and keys…aside. Humans are far behind the curve, by many millions of years, on this front once the rest of the animal kingdom is considered, because just like with light (which I’ve talked about before), many animals can produce their own electricity.The overwhelming majority of these animals are at least partially aquatic, since water is a far better conductor of electricity than air. Of these gifted organisms, the bulk of them are vertebrates, and in particular, among our finned and gilled friends, the fishes. There are some mammalian exceptions, including monotremes (the platypus and echidna) and perhaps a species of dolphin or two, but by and large, it’s fish that have locked down this electricity thing. Volta, Tesla, and Edison were great and all, but the reality is that animals not too distantly related to the flaky goodness in your Gorton’s fishsticks had them solidly beat by eons, evolving a commanding grasp of the power of electricity right into their bodies.

On a microscopic scale, there are electrical properties observable in essentially all animal, plant, and fungal cells, as there is an inherent voltage difference maintained between the surface of the cell membrane and the interior of the cell. This voltage condition stays stagnant in most cells, but in some animal cells, like nerve and muscle cells, the electrical membrane potential can quickly rise and fall (generating the release of an “action potential”; see: neurons in brain “firing”) through use of special gates in the membrane that pump charged atoms (ex., sodium ions) across the membrane in an incredibly fast cycle of increasing electrical potential, followed by sudden, temporary, dramatic reversal of membrane polarity. This process is critical to the response of these cells to external stimuli, the facilitation of intercellular communication, and, ultimately, the relay of information through cellular circuits. Your neural, muscular, and hormonal systems are made useful by the tightly orchestrated rhythm of many trillions of daily electrical impulses from innumerable, tiny, cellular batteries. Every thought, every heartbeat, every movement you’ve experienced has been instigated by the flashing of all-or-nothing action potential spikes. Your life, from the perspective of your excitable systems, is a bit like an 80 year long rave, faithfully illuminated by the regular pulsing of strobe lights…but with less MDMA and ketamine.

Cellular level mastery of electricity is nearly universal in the animal kingdom, however, and the capacity of the “electric fishes” to step it up to the scale of the whole organism is something special. This generally occurs in two forms: electroreception, which is more common and involves the ability to perceive natural electrical fields as a kind of “sixth sense”, and bioelectrogenesis, which is when the animal actually produces an electric field or discharge. Many electrogenic fish, which are the focus of this entry (because they are badass), are also electroreceptive, and can use their produced electrical ‘aura’ to enhance their perception of their environment, or even communicate with other members of the same species.

“Baby girl, turn me on with your electric feel…”

Perhaps the most obvious example of bioelectrogenesis in fish is the electric eel (Electrophorus electricus…no surprises there). It’s not technically a “true eel” (fishes in the order Anguilliformes), and is actually a knifefish (order Gymnotiformes), a group of slender,  freshwater fish found exclusively in South America that are related to catfish, carp, and minnows. All knifefish have the ability to produce an electrical field, but this power is excessively enhanced in good ol’ Electrophorus, which also happens to be the largest member of the Gymnotiformes, reaching the length of a couch.

Much of that impressive length is made up of the electric organs. These organs, common to all electric fish, are made up of evolutionarily-derived muscle or nerve cells, called electrocytes. Electrocytes are disc-shaped and stacked closely together (think Pringles chips layered in their container), so that each one adds to the total difference in electrical potential, somewhat like a voltaic pile, or the plates in the lead-acid battery that starts your car. The electrocytes, numbering in the many thousands, once stimulated by the neurological system, go through the same rapid, electrochemical switcheroo found in normal muscle or nerve cells, suddenly, almost simultaneously, reverse in polarity, and effectively generate an electric current that runs down the length of the organ and out into the surrounding water…all in a fraction of a second. In Electrophorus, the cumulative effect of all of these electrocytes discharging at once is extremely powerful…definitely strong enough to be used both for stunning prey (invertebrates and smaller fish), and for defense. If your butthole isn’t adequately puckered at the thought of that, note that adults can deliver a punch registering at upwards of 500 to 700 volts with a current of 1 ampere, which is enough of a shock to stop the heart of pretty much any animal on the planet sufficiently foolhardy enough to tangle with Electrophorus, something this predator found out the hard way. For some perspective, consider that if you could harness an entire Electrophorus discharge, you could power something like a hot plate or microwave. Or a decked out Christmas Tree.

So, electric eels, if sufficiently agitated by meddlesome humans, can potentially remedy the situation by replicating the exhilarating experience of shoving a knife in a household wall outlet, resulting in the perpetrator’s immediate demise. Death-by-eel is rare for humans, but it does happen, sometimes merely as a result of drowning after being blasted unconscious. Therefore, it’s advisable not to mess with Electrophorus, unless you think being found face down, floating in a swampy, Neotropical puddle, dispatched by a pockmarked fish that didn’t even touch you, seems like a dignified way to go.

Electrophorus may be the most famous, and dangerous, of the electric fish, but there are certainly many additional, possibly even stranger, species that receive little attention. And no, this guy isn’t among them.

A not-so-distant relative of the electric eel, found all the way across the Atlantic in tropical Africa and the Nile River, is the electric catfish (family Malapteruridae). Externally, malapterurids look like conventional catfish. Species range in size from about the length of your hand, up to the size of your leg. Many are dull brown in color, and sort of look like little smokies with eyes and tentacles.

Take THAT, appetite for breakfast tomorrow!

Its electric organ, derived from muscle tissue, lines the body cavity as a sheath, or (and I apologize for continuing with the breakfast meat imagery) a bit like a sausage casing. Using this organ, electric catfish of the genus Malapterurus can produce a discharge in the 300 to 400 volt range. This is enough of a wallop to discombobulate small fish for food, or to defend itself. The shock isn’t fatal to humans, but the jolt from a good-sized fish is guaranteed to be persuasive at getting you to let go of it pretty damn quickly.

These fish, and their electrical capabilities, were familiar to the people of ancient Egypt. Texts from nearly 5,000 years ago refer to electric catfish as the “Thunderers of the Nile”, and are among the earliest known acknowledgements of electrical phenomena. Smaller fish were used in a medical context, their shocks recruited for treating diseases of the nervous system like some sort of proto-electroshock therapy. Larger fish were wisely avoided; with them, it would more with the sizzling, and less with the salving.

Saltwater environments have their fair share of electric fishes as well. One inhabitant beneath the briny waves is the electric ray, also known as the “torpedo ray” or simply “torpedo.” They are different enough from other rays to comprise their own taxonomic order, Torpediniformes, one of the four major groups of rays (the others being skates, stingrays, and sawfish). The name of the group is not inspired by the naval weapon, but rather, the other way around. The “torpedo” device borrowed its name from a common genus of electric ray, Torpedo, in reference to the weapon’s ability to “stun” enemy ships. And by “stun”, I mean “sink.” The name of the fish comes from the Latin word torpere, meaning “numbed” or “paralyzed” (torpor…get it?). So, perhaps obviously, the ray’s name does not come from any physical similarity to an actual torpedo.

If we’re going by looks, I’d start with “black flapjack” for this guy. Or “punctured tire.”

Torpedo rays inhabit coastal waters the world over, and are ambush predators, shuffling their flat bodies underneath the sand and hiding in wait for prey. A brief zap and a voracious gobble and it’s over for whatever poor, oblivious bastard drifts by; a case of “shock and maw.” Unlike in electric eels and catfish, the electric organ of the torpedo ray exists as two, horizontally-oriented stacks of electrocytes on either side of the head. The electric discharge flows from the bottom of the ray’s body (the side with the mouth), up through the electric organ towards the top of the body and out into the seawater above…which is conveniently the “dinner arrival zone.”
Saltwater is more conductive than freshwater, so torpedo rays can get away with lower voltages (under 200 volts) in their discharges, but have somewhat higher amperages. Shocks from the largest torpedo rays (Torpedo nobiliana, pictured above, can reach the mass of a grown man) can be excruciating, but are not fatal to humans.

Like the electric catfish, torpedo rays are known from antiquity for their electrogenic properties and their use in medicine. Their role was mostly as a kind of anesthetic, since their shock would temporarily numb the patient. The Romans occasionally used them to treat headaches, and the ancient Greeks even used them to block out some of the pain of childbirth, because apparently that whole ordeal isn’t stressful enough for Mom without the experience of being smacked with slimy jump cables thrown in. It is unknown if any of the children were imbued with Magneto-like superpowers from the ray’s electricity…or powers like that kid in “Powder.”
The Greeks also employed the services of the torpedo ray in surgery, where it could be used as a localized anesthetic. Torpedo rays were evidently a lot like Flintstonian appliances in Greek society, electrocuting away the pain. Morphine? Try more-fin.

“Forceps, please…scalpel…fish.”

Another group of ocean-bound electric fishes are the stargazers (family Uranoscopidae). They live a life much like the torpedo rays, shallowly submerged in the sand on the continental shelf, hungrily awaiting prey to unwittingly swim by. They are squat-bodied monstrosities, with massive, forever-upturned faces (hence the name “stargazers”), primed and ready to strike upwards from the sand with their rapidly extendable jaws. Based on their frozen expressions, they also appear to be perpetually in a foul mood.

Your move, Grumpy Cat.

All stargazers are venomous, possessing two hollow spines behind the eyes to deliver the toxic cocktail when attacked…or accidentally stepped on by a soft, squishy, human foot. But, apparently this shit wasn’t impressive enough for a few species of stargazer, which have also evolved small electric organs derived from muscles in their damn faces. The shock put out by this turd-with-attitude isn’t much compared to the other fish previously mentioned, but it certainly helps stun small fish in that fraction of a second before the stargazer can shoot its toothy gob upwards to vacuum the unfortunate sucker in. It’s of no danger to animals as big as us, and run-ins with the jolt of a stargazer are more surprising than painful; less like grabbing a high-voltage fence and more like getting unexpectedly smacked in the chest with a basketball. For humans, its phaser is set to “stun.”

One species in the genus Uranoscopus even has a tag of skin on its lower jaw that it wriggles as a worm-like lure for small fish, getting them just close enough to electrocute and devour. This is kind of like advertising a garage sale, and then when the first curious visitor arrives at your house, you jump out of the hedges, zap him with a taser….and then eat him? Maybe it’s not a perfect analogy…

Bioelectrogenesis on the organismal scale has evolved multiple times in very different groups of fish, living in different parts of the world and in varied habitats. This “funneling” down into shared evolutionary strategies among independent lineages is a remarkable example of convergent evolution, and it was something that Darwin took care to note in his Origin of Species. From the cells of our most vital of tissues, to the beauty-deficient stargazer, to the genuinely deadly King of the Knifefish, the “spark of life” shares space with something far more literal. Life is an uncannily clever tinkerer, and bioelectrogenesis is just one spectacular representative of a great multitude of tools that have been intricately carved out by the tireless processes of evolution.

Image credits: Lightning, electric eel, electric catfish, surgeons, torpedo ray, stargazer

© Jacob Buehler and “Shit You Didn’t Know About Biology”, 2012-2013. Unauthorized use and/or duplication of this material without express and written permission from this blog’s author and/or owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Jacob Buehler and “Shit You Didn’t Know About Biology” with appropriate and specific direction to the original content.

Arachnids: Hooded Tickspiders

Hooded tickspiders.

Yes, I can sense the readers of this entry promptly throwing in the towel, giving up on life itself at simply reading the name of such a creature. Let the idea that Mother Nature is a nurturing, caring force be put to bed immediately, for evolution has crafted the cruel curveball that is the hooded tickspider; equipped with all the charm of a blood-gulping, parasitic tick, and the charisma and affability of a spider. Why even bother leaving the house at this point, what with such unholy, Dr. Moreauian amalgamations walking around? What’s next, cobra-tigers? Leech-sharks? Manbearpig?!

While it is certainly anxiety-inducing to contemplate an animal that seemingly exists as two highly-loathed arachnids essentially smushed together, as if done so to be an entry in a competition to generate the most unsavory Doritos Collisions flavor marriage of all time, in reality, this isn’t the case at all. Just as antlions are neither ants or lions, and dragonflies aren’t dragons, and aren’t really ‘flies’ either, the hooded tickspider represents a unique breed of creature, distinct from both ticks and spiders. Hooded tickspiders belong to a small order of arachnids; Ricinulei. There are about sixty species worldwide, making Ricinulei currently the least speciose order of arachnids, but more species are discovered as the years go by.

If you are breathing a sigh of relief as horrific imagery of web-weaving blood-suckers with no other mission than to patiently wait for you underneath the lip of your toilet seat peacefully leaves you, don’t get ahead of yourself. While hooded tickspiders are no threat to people (for a number of reasons related to their anatomy and extreme cryptic nature), they definitely provide enough innate, unnerving creepiness to make up for it.

Given the miraculous chance that you would encounter one of the few dozen species on Earth in the wild (which would inevitably involve you rooting around in the dirt and leaf litter for weeks in West Africa or the tropical Americas…because those are the only places they are found…and infrequently, at best), the hooded tickspider would probably yield more disappointment than colon-emptying terror. Truthfully, they aren’t much to look at if you aren’t familiar with what to look for. You won’t likely find anything even rivaling the size of the nail on your pinky finger, and they have all the brash coloration of a burlap sack. A captured, tiny, soil-caked hooded tickspider, curled into a defensive, ball shape, would be virtually indistinguishable from your common garden spider to the untrained, non-arachnologist eye.

However, if you were to take a closer look, you would quickly find that the pathetic, trembling critter in your hand appears to be missing something relatively important.
Like a head.

If this still-living animal were a vertebrate, and not an arthropod, you would probably be bounding off into the forest like fucking Ichabod Crane. But no, you, hypothetical, intrepid naturalist-person, know that arthropod nervous systems aren’t nearly as centralized in the head region as the nervous system belonging to cats, dogs, horses, and ourselves. Shit, cockroaches can live for weeks without their heads, in true Steven Seagal, “Hard to Kill” fashion. Perhaps that is what’s going on with this little guy? Maybe the head is nowhere to be found, but the body hasn’t caught on yet?

Well, that’s not correct either. It’s not so much that hooded tickspiders “took a little too much off the top” evolutionarily, it’s just that the “head”, or rather, all the parts associated with it, is obscured by a structure that is the origin of the first part of their common name. In the place where you’d expect to find head-bound organs found in the vast majority of normal, Earthling animals, there’s simply…nothing. Just a flat, exoskeletal plate. It’s like if your body was normal all the way from your feet up, but stopped abruptly at a goddamn manhole cover resting on your shoulders. This plate is known as the “hood” (and to arachnologists, the “cucullus”, which is Latin for “cowl”).
And of course, perpetually faceless, dark, hooded individuals are generally stand-up, good-natured characters. Nothing to fear at all.

So, the question becomes: what in the hell are tickspiders hiding under there? What secrets are they keeping from us? Well, you can sure as shit bet that it isn’t jelly beans or chocolate or anything remotely pleasant. Just like a manhole cover, this “cucullus” is movable, and if retracted reveals…not a whole lot, actually. The big “surprise” is a vacant mouth opening under there, along with a pair of chelicerae (mouth “parts” that are standard for all members of the subphylum Chelicerae) that end in sharp little claws, and that’s about it.
Hooded tickspiders don’t even have eyes, above or below the cucullus. But, despite being completely peeperless, they are highly sensitive to light, and likely achieve this capability through photosensitive cells placed laterally along their hard, outer cuticle (ancient, fossil species had eyes in these locations, but as hundreds of millions of years have gone by, the eyes appear to have been reduced). But as for discerning their immediate surroundings and navigating through their humid, forest floor world by way of light-based vision? Not happening. Hooded tickspiders blindly clamber along the leaf litter, fumbling around and feeling for any small insect or other critter in its path. It is then believed to snatch up the unfortunate morsel with its pair of small, delicate, claw-tipped pedipalps (the same appendages that have been modified into thick claws in scorpions), and then proceeds to stuff pieces of the hapless victim into its empty, butthole-like mouth. They are diminutive living tanks, half the size of the keys on your computer keyboard, yet covered in a heavy, air-tightly riveted together exoskeleton so extensive and impenetrable that it instead of a normally vulnerable face, it has a vault door. Like some kind of goddamn arachnid Death Star, it has a single observable opening, a tiny, tangible chink in its fortification…and even that is constantly shut up in the biological panic room formed by its “hood.” Up close, they look more like a human-crafted vehicle than a legitimate animal, appearing to simply be missing headlights and a grill.

Outside of the strange head region, the anatomy of members of the order Ricinulei is fairly normal compared to most arachnids. Sure, the exoskeleton is hard and super-durable, but the general body blueprint (sometimes referred to as a “bauplan” by biologists) fits the arachnid archetype. Cephalothorax (including head organs…or what remains of them), abdomen, eight pairs of walking legs…the works.
However, some elements of the 2nd and 3rd pair of legs are a bit odd in many species of hooded tickspider. For instance, the 2nd pair of legs is typically elongated, and leads far to the front when the animal is walking; it is thought that these legs act as sensory organs in a way, carefully guiding the animal by an acute sense of touch. The males of many species have even larger 2nd pair of legs, with hyper-muscular, comically bulky segments. These limbs may be used in male-to-male combat, where the two individuals would likely jostle with each other using them, perhaps trying to push the competitor aside or into a position of inevitable submission. This aggressive, competitive behavior is ubiquitous in the animal kingdom, and is observable in the clashing antlers of male deer, the brutal whipping of necks between male giraffes, and pretty much any weekend at a collegiate fraternity party when alcohol, in any amount, is consumed.

The 2nd walking limb morphology of males of this species (Pseudocellus chankin) has been described in the literature as “hella swoll, brah”

So, the 2nd pair of walking legs in hooded tickspiders tend to be modified, albeit in different ways and degrees, in both males and females. However, the 3rd pair of walking legs, in males, has evolved to carry out a very gender-specific function. In males, these legs end in a weird, fan-shaped cluster of nubby projections that form a scoop. During hot, hot hooded tickspider sex, the male uses these scoops like a lacrosse stick to cup and manipulate a spermatophore (a solid, gelatinous mass of sperm, basically; commonly used in arthropod reproduction, especially in arachnids), and then, once in position, lovingly crams it into her ovipore. So, it’s less like familiar, human sex and more like spackling a hole in a wall, but hey, apparently it’s been working for hundreds of millions of years just fine. You would be wise in pitying the female hooded tickspider, whose pinnacle of romantic experiences involves a clumsy, blind mate bumbling towards her lustfully, with fistfuls of his own spunk.

“…ladies?” *wink*

After a hasty copulation, and reception of the male’s seed fastball has occurred, the female lays a single, fertilized egg. This egg is then stored underneath the “hood” until it hatches sometime later, into a six-legged, soft-bodied larva that, over a surprisingly long amount of time, progressively molts into an eight-legged mature form. The intimate care that the female provides this single offspring represents a fairly rare parental tendency within arachnids, although it is similar to the motherly devotion to progeny exhibited by whip-spiders (something I examined in the first entry in this series on arachnids). Undoubtedly, carrying the egg in that tight area between the cucullus and mouth for so long is burdensome for the mother, and is a sacrifice that I would consider of evolutionary significance. It would be interesting to examine the long-term fitness consequences of the female hooded tickspider’s habit of stuffing their eggs underneath their face plates.

Fuck off, Easter Bunny. This hiding spot’s taken.

Perhaps the oddest thing about hooded tickspiders isn’t their outward appearance, but their strange legacy of discovery and their evolutionary history. The discovery of the order Ricinulei occurred in 1837 in England as a fossil representative from roughly 300 million years ago. It was originally misidentified as a beetle in the original literature, but it was soon revealed to actually be representative of a previously unknown group of arachnids. Only a year later, a living species was discovered in West Africa, making hooded tickspiders one of the few groups of animals on the planet who were first described through fossils of extinct species, and only later on observed still hanging out, alive, in the modern era (a more famous example of this situation is the coelacanth).
This is sort of the equivalent of suddenly discovering living Triceratops in some remote region of the tropics…except, you know, way less awesome.

As far as we can tell, Ricinulei is a very old group, dating back to at least 320 million years ago or so, and they’ve changed remarkably little since that time. As for their place in the arachnid family tree, two main lines of thought currently exist. The first is that hooded tickspiders are most closely related to the group containing mites and ticks (subclass Acari). This is based on similarities in early development (the six-legged larval stage is shared between tickspiders, ticks, and mites), as well as similarities in their mouthparts. The other competing hypothesis is that Ricinulei represents an old, still-surviving arm of a long-since extinct group of arachnids known as trigonotarbids. The order Trigonotarbida existed from about 400 to 300 million years ago, and was made up of arachnids vaguely similar in body shape to spiders, but with many plates (called “tergites”) running down the abdomen and no ability to produce silk. According to paleontological evidence, both trigonotarbids and hooded tickspiders had/have curious claws on the tips of their pedipalps, and a unique mechanism joining the two halves of the body is found in both groups, and exclusively so.

Wherever the hooded tickspider lineage comes from, there is no doubt that living representatives are among the oddest, and least understood, arachnids we have around. We are slowly learning more and more about these enigmatic little, faceless beasties, and we are continually revealing additional information about their strange life histories, diets, and origins. While I find them unavoidably fascinating, none of this makes them less unsettling, however, in my book. If you feel the same as me, and you fear your nightmares will inevitably be filled with armies of functionally decapitated, eight-legged, sperm-chucking, spidery demon-spawn after reading this entry, just let the following visual of Eowyn vanquishing a hooded menace play in your head as you peacefully drift off to sleep tonight.

Yeah. That’s the stuff.

Image credits: Opening hooded tickspider, Pseudocellus chankin

© Jacob Buehler and “Shit You Didn’t Know About Biology”, 2012-2013. Unauthorized use and/or duplication of this material without express and written permission from this blog’s author and/or owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Jacob Buehler and “Shit You Didn’t Know About Biology” with appropriate and specific direction to the original content.

Sea Spiders

Sea spiders.

I can already hear the exasperated groans coming from the readership of this entry. Sea spiders? Seriously? Why, arachnophobes the world over sigh, are spiders not content to just stay where they belong; many miles away from any potential interaction with my relatively exposed, swimming body? Need they go out of their way to ruin my summer vacation at the beach too? Why do there have to be marine versions of our creepy, spindly-legged friends, especially when we already have sea snakes, saltwater crocodiles, and what are the equivalent of massive “sea wolves” patrolling the briny depths? Perhaps, given the unsettling, lanky body shape of the sea spider, reminiscent of the daddy longlegs clustered in the dark, dusty recesses of our garages, it provides little comfort to say that these animals are not what their common name suggests.

In the same way that “sea cows” are not actually cattle equipped with flippers, and “sea wasps” aren’t really our delightfully sting-happy, land-lubbing acquaintances finding a new home beneath the waves (a nightmarish scenario if there ever was one), sea “spiders” are not simply spiders with water-proof webs and an appetite for calamari. They are something altogether different, belonging the taxonomic class Pycnogonida (meaning “thick knees”, perhaps referring to the shape of the joints in their segmented legs, or a cruel high school nickname for the group). This class is currently allied within the arthropod group known as Chelicerata, which does include arachnids; but, these “sea spiders” are, as previously mentioned, not arachnids themselves. However, even this classification may not provide enough recognition of the pycnogonid’s unique pedigree. There have been some recent studies (from both molecular genetics and evolutionary development angles) that suggest that sea spiders are not nested alongside arachnids at all, but instead are a part of a much older offshoot of the arthropod line…and are potentially the only surviving, highly-derived representatives of some of the first groups of arthropods to evolve (perhaps more closely related to enigmatic, extinct animals from more than half a billion years ago like Anomalocaris). If this is the case, then the pycnogonid lineage is effectively among the oldest animal groups on the planet.

Yes, no matter which classification assignment is correct, these critters occupy a unique branch on the great tree of life, and once someone takes a look at these pycnogonids up close, it becomes abundantly clear that these animals definitely deserve severely distinct classification, and have a tangibly alien quality to them. Seriously, pycnogonids are about as weird as it gets.

In case you haven’t noticed yet, I’ll point out that pycnogonids have incredibly long legs.

Less of a “body with legs” setup, and more of a “legs that have a body” situation, really

These absurdly elongated walking legs (which usually number in four pairs), combined with a comically reduced, skinny body, make the pycnogonid a curious sight to behold. While some species use these hair-thin limbs to swim by way of turning the leg into a paddle through the use of long bristles, often times, the legs function in the traditional sense, allowing these creatures to stride along the sandy ocean floor. But, despite being nearly entirely made up of legs, sea spiders are not swift like their terrestrial namesakes. The musculature devoted to locomotion is pretty damn pathetic, allowing only for slow, deliberate movements that are somehow both eerily robotic and graceful. Indeed, pycnogonids, with their cartoonishly proportioned bodies and cold, calculating progression across the open wastes of the abyssal sea, each step gliding unhurriedly forward without any hint of hesitation, they seem not only alien, but artificial. It’s easy to imagine them as mechanical automatons, marching silently across the pitch-black plains of the deep.

As if this notion of our oceans being inhabited by hoardes of robo-spiders didn’t need any additional reinforcement, consider the spine-tingling fact that pycnogonids don’t possess anything resembling a respiratory system. That’s right; no gills, no lungs. A respiratory system would likely be a cumbersome and unnecessary bit of visceral decoration inside that minimalist body of theirs. Pycnogonids simply absorb oxygen passively from the water that surrounds them via diffusion (the movement of molecules from high to low concentration), a strategy that is undoubtedly made possible by their bodies’ high surface-area to volume ratio. So yes, pycnogonids, in a disconcertingly similar fashion to the soulless, automated drones in any science-fiction flick, do not draw breath, in any form.

Their digestive system is also radically impacted by their bizarre body shape. The insides of the body segments (collectively grouped into a “cephalothorax”) of pycnogonids are apparently so cramped, that the digestive system has projections that extend into the tops of the walking legs. Pycnogonids are experiencing what, in humans, would be like wearing a corset so tight it made your intestines squirt into your thighs…inevitably resulting in a lifetime confusion between indigestion and Charley horses. Sea spiders are plagued by the pressure to fit “10 pounds of shit in a 5 pound bag”, and the evolutionary answer of having some of their guts wander out of their body cavity is made a necessity by the pycnogonid quirk of having a dramatically reduced abdomen (that big, bulgy segment at the back of arthopods like insects and spiders), which provides essentially zero auxiliary room for relatively important things…like organs. Pycnogonids end up cramming the equivalent of a house’s worth of belongings into a studio apartment, and they manage to achieve this by evolutionarily converting their innards into a game of Tetris.

The business end of the pycnogonid, the eating end, isn’t any less strange. The head of a pycnogonid is an obvious departure from that of its hypothesized closest relatives; the rest of the members of the subphylum Chelicerata (a brief overview of which I explored in this recent entry). The most glaring difference is that in place of paired, mobile mouth parts (such as those found in arachnids and horseshoe crabs), the main tool used to procure food is a proboscis, which manifests as a trunk-like appendage that in some species is short and squat, but in others is a monstrous organ possessing a shape somewhere between that of a bowling pin and the nose of that giant Muppet, Sweetums. Accompanying the proboscis in the head region, are typically three pairs of appendages distinct from the walking legs; they are the chelifores, palps, and ovigers. The chelifores and palps are more actively involved in gripping and manipulating food items, while the ovigers, placed furthest back on the body of the three pairs, is more heavily involved in reproduction. Ovigers, usually the longest appendages outside of the legs, and found folded up underneath the body, are often used in courtship displays and for cleaning the exoskeleton. It is the pycnogonid male that carries and cares for the fertilized eggs, tucking them underneath the body and using the ovigers to ball the eggs into two large, globular clusters. This gives the animal the appearance that it is wearing white mittens and then sticking them in its armpits. Allowing for the sea spider to survey its world, perched on top of the cephalothorax, near the head region, is an eye turret (called an “ocular tubercle”) that houses four simple eyes.

Most species of sea spider are exclusively carnivorous, and either take live prey or scavenge it off the ocean floor. The proboscis, which can occasionally have spines or teeth arming the lips at the tip, is employed as the pycnogonid weapon of choice when dining. Commonly, they will feed on big, stationary, soft creatures like segmented worms, sea anemones, and sponges by stabbing their proboscis into the side of these animals. Then, aided by a cocktail of digestive enzymes streaming out of the proboscis, the sea spider slurps up a hunk or two of delicious tissues directly into its gut, and then gets the hell out of there to move on to the next sorry schmuck on the seabed.

Wanted: for a suck-and-run

If the idea of being leisurely stalked by a pycnogonid and aggressively pierced by nature’s meanest variation of the bendy straw is keeping you from going snorkeling anytime soon, then you should reconsider. Firstly, pycnogonids, creepy as they are, do not view humans as food, and probably couldn’t do any damage with that Gonzo schnoz even if they tried. You’d be more likely to drown from getting entangled in seaweed, than to receive even the slightest pinprick from the proboscis of a sea spider. This reality is enforced by the diminutive size of the vast majority of pycnogonid species. Most pycnogonids you’ll observe in the wild are small as shit, with leg-spans only stretching as wide as the nail on your pinky finger. These characteristics make our alien, arthropod friends pack as much deadly force as a wind-blown dandelion seed.

However, exceptions to the rule abound in the natural world, and in the case of pycnogonids, it is size. While most of the 1,300 or so species of sea spider are found in shallow waters near shore, and are quite tiny, there are a small number of species found in the coldest parts of the ocean that are comparatively gigantic.

Looks like even the ruler is afraid to get close

Meet the aptly-named Colossendeis, a genus of pycnogonid that has representative species in all oceans of the world. However, it is in the icy waters surrounding Antarctica that some species, like the one above, possess such massive bulk. The largest species of Antarctic giant sea spider have leg-spans as wide as a trash can lid and proboscises as long as your finger. This significant increase in size compared to other sea spiders fits into two phenomena effecting marine invertebrates; polar gigantism and deep-sea gigantism. The latter of these two has been documented to occur across many groups of organisms in the deepest parts the ocean, where inhabitants of the abyss are many times larger than their shallow water relatives; examples include cat-sized, scavenging isopods (relatives of terrestrial “pill bugs” or “roly polies”), and the numerous varieties of giant squid. Explanations for this phenomenon have been offered over the years, and one prominent hypothesis is that the cold waters of the deep encourage an increased life-span, and in the case of many invertebrates (which tend to grow continuously throughout their lives) this results in a much larger adult size. This reasoning would also be consistent with polar gigantism, in which species of marine invertebrates in cold polar waters, at any depth, also exhibit an increase in size compared to their closest, lower latitude relatives. The giant sea spiders of the Antarctic are both found in deep water, as well as the still quite cold surface waters, and are thus candidates for both described tendencies. Of course, despite their intimidating size, even Colossendeis sea spiders are benign animals.

“Unhand me! Now! Or I shall lightly poke you with my proboscis and tickle you with my legs!”

Pycnogonids may look like someone took a spider, starved it, gave it a shiny coat of monochromatic paint, threw it in the ocean, and made it walk backwards…but they are, in reality, a fascinating group of animals with few relatives. Pycnogonids are something of a staggeringly old taxonomic island, a distinct offshoot existing for several hundred million years. There are more than 1,000 modern species, but we don’t know as much as we’d like about them, and we are just now starting to get a grasp of their ancient evolutionary history through the fossil record and genetic studies. In time, we may be able to unlock some of the pycnogonid’s mysteries, and get an even greater appreciation for the slow, silent, stilt-walking figures that have been pestering sponges and anemones the world over since before the Age of Dinosaurs, and will hopefully continue to do so for eons to come.

Image credits: Opening sea spider, red sea spider, striped sea spider, Colossendeis, held Colossendeis

© Jacob Buehler and “Shit You Didn’t Know About Biology”, 2012-2013. Unauthorized use and/or duplication of this material without express and written permission from this blog’s author and/or owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Jacob Buehler and “Shit You Didn’t Know About Biology” with appropriate and specific direction to the original content.