Mesmerizing Marine Mimics: Wolves in Sheep’s Clothing

This post is the fifth in a six post series outlining the evolution of mimicry within the ocean realm. These posts detail various ways in which organisms may copy other organisms in appearance and behavior, and the evolutionary context for how these mimic-model pairings have come to be. The first entry in this series goes over some fundamental introductory concepts and definitions regarding mimicry in general.

Animals can be real dicks.

Hermit crabs congregate solely to aggressively covet bigger and better shells, eventually leaving at least one or two crabs forcefully foreclosed upon and left to wander the beach, squishy, defenseless, and homeless. Lovable dolphins routinely slaughter porpoises that stray too close to their turf, but not without sexually assaulting and mutilating them first…you know, just because. Male mallard ducks are such a charming combination of unhinged sexual aggressiveness and zero regard for consent that females of the species have evolved vaginal labyrinths to stymie the effectiveness of the penetration of the corkscrew Johnsons of their feathered assailants. The natural world is chock-full of organisms being outright bastards to one another, because life is rough, and sometimes those that are more Shkreli than Gandhi scam and abuse their way to evolutionary success. In the river of Life, the fork that yields survivorship, high fecundity, and a strong genetic legacy is typically navigated by a very special variety of watercraft: the douche-canoe.
The phenomenon of mimicry is certainly not immune from nefarious applications, and many taxa use mimicry to gain the trust of other species, only to con them…potentially out of their lives. This flavor of mimicry, where an organism mimics a species perceived by others as benign (or even beneficial) to gain access to resources (food, mating opportunities, etc.), is called “aggressive mimicry.” I’ve brought it up briefly before in this post series, in particular when talking about fish that use lures to persuade prey to practically swim into their waiting gobs, like with the decoy scorpionfish or the frogfish. However, there are some marine critters that take the cake when it comes to the Machiavellian style of mimicry. The fish that this blog post will explore shamelessly engage in as much sociopathy, brazen laziness, selfishness, and manipulative scheming as you’ll find this side of an episode of “It’s Always Sunny in Philadelphia.”

Take, for example, the hamlet fishes (genus Hypoplectrus), a collection of small, typically brightly-colored groupers found in the tropical West Atlantic and Caribbean. Hamlets are ridiculously tiny by grouper standards, considering the largest members of the family can grow as large as a smart car, but are nonetheless incredibly competent, voracious predators, snapping up small crustaceans as they patrol the maze of the reef. Sneaking up on wary prey, and keeping it wonderfully oblivious until the very last moment, is a difficult task for any predator, so it pays to be able to get close with minimal effort….and it’s thought that a few species of hamlet have managed to do just that.

The living police car beacon light below is the blue hamlet (Hypoplectrus gemma). It, like the other hamlets, grows to a handful of inches and has a face only a mother could love.

I haven’t seen a hamlet this blue since the Prince of Denmark fondled a jester’s skull

Hypoplectrus gemma just so happens to share its Caribbean and Gulf of Mexico geographic range with another fish, the blue chromis (Chromis cyanea). Chromises are damselfish (family Pomacentridae) and have a diet generally consisting of tiny, suspended particles of food in the water column. While they can be cantankerous, bitey little pricks in regards to defending their territory and eggs from other fish, damselfish, with their tiny mouths perfectly suited to pecking at planktonic flakes, aren’t exactly the predatory scourge of the reef. The blue chromis is no exception.

Pictured: Probably not a shark

For this reason, the small crustaceans on the reef (shrimp, crabs, and the lot) don’t have much to fear from the blue chromis. What they do shit their ten-legged pants over are hamlets, which are ever-hungry Bubba Gump addicts with (much like other predatory fish) a mouth that sucks harder than a DVD of “Transformers: Age of Extinction” taped to a Bissell. If they sense the clear presence of a hamlet, wiser crustaceans make sure their exoskeletal asses are well hidden in the smallest grooves and pores in their coral surroundings. So it’s a good thing for the blue hamlet that it, as you may have noticed, looks remarkably similar to the comparatively harmless blue chromis. It’s thought that to the common crustacean on the reef, with simple eyes unable to discern fine details, the blue hamlet is basically indistinguishable from a blue chromis….allowing the hamlet to leisurely approach its crustacean prey without raising any red flags. From the perspective of the shrimp, an inoffensive little damselfish, barely worth considering, is just drifting into its personal space…like a fly casually landing next to you on a park bench. You may not even register that the fly is inches away from your leg. Why would you? Flies aren’t dangerous, incredibly common, and there’s not really any reason to notice them at all. If that fly promptly swallowed you in one tremendous gulp, you wouldn’t be able to say you saw it coming. The same goes for the shrimp and the “damselfish” that floated over to say hi. It’s possible that taking advantage of the reputation of the blue chromis as an inconsequential wallflower allows the blue hamlet to cruise through its predatory life with the difficulty setting on “easy”, feigning innocence long enough to straight up murder meal after meal after meal.

I say it’s “possible” that this is the case, because no one, to my knowledge, has actually confirmed behavioral mimicry in this species of hamlet, and the level of mimicry in blue hamlets (and a number of other hamlet species that are proposed to mimic different types of damselfish) appears to be limited to severely suspicious similarity in color and appearance between the mimic and the model. Well, with the exception of one hamlet species. The butter hamlet (Hypoplectrus unicolor) is an apparent mimic of the four-eyed butterflyfish (Chaetodon capistratus)…a fish that you may remember from the last post in this series as being an automimic, flashing confusing eye spots when confronted with danger (yes, the model for the butter hamlet’s mimicry is in fact another mimic). Butter hamlets not only wear their model’s colors, they also follow the butterflyfish around the reef like a puppy in an attempt to blend in more effectively (possibly appearing to be the butterflyfish’s mate). The hamlet also uses this convenient opportunity tagging alongside the butterflyfish to try and suck up as many crustaceans as possible….in fact, about half of all the hamlet’s predatory strike attempts are made when it is using its model as a unwitting wingman. The butter hamlet apparently hardly goes through the effort of trying to eat unless it is actively mooching off the presence of its model to further dupe its prey. These fish are about as principled as the guy who fakes homelessness to gain access to a food pantry so they can pocket as much grub as possible before dashing out the door.

It’s one thing to fly under the radar as an uninteresting, benign reef fish in order to score your dinner. It’s something entirely different to convince your meal that not only are you harmless, but that you are their friend. That you are there to help.


Just a big ol’ pot of altruism you are. Honest….

Ocean ecosystems are a cauldron bubbling over with life: fish flitting and spawning everywhere, countless organisms living, pooping, and dying, vast fields of pelagic plankton converting carbon dioxide and nutrients into grand scale blooms. The sea is like a well-used, never cleaned, fraternity hot tub at the end of a long, sweaty, rambunctious summer; crusty, high in biodiversity, and swimming with critters you’d rather pretend aren’t in there. Life, just by existing in this saline soup, tends to have other life invade, infect, and coat it liberally; there is no escape. External parasites are pervasive in the marine realm, and cling to the outside of larger animals with a stubborn, death-grip of permanent stickiness only outmatched by what fucking glitter does whenever it comes in contact with human skin. These irritating stowaways, often times blood-sucking crustaceans like sea lice and roly-polies that live like leeches, aren’t exactly an appreciated gift of the sea by the animals that have to deal with their shit. Parasites drain precious energy and resources along with the blood they sip, and in the unforgiving wild, having an assload of freeloaders drinkin’ up your go-juice is a fine way to have your anemic keister end up deader than it was last week. Simply put, parasites end up weakening their hosts…so it behooves the besmirched, non-consenting smorgasbords to have them removed. Oh if only such a means existed…

Stepping up to the plate is a fish that specializes in making itself incredibly useful to the other fish in its community; the cleaner wrasse (Labroides). Labroides wrasses, of which there are five species, are known as “cleaner fish” (which is a role held by more groups of fish than just these wrasses), meaning that they prune and pick parasites off the scaly outsides of other fish. Cleaner fish don’t do this bit of public service as part of getting their Goody Two-shoes Badge in the Neptune Scouts or something…they get the bulk of their nutrients from the parasites and mucus layer on other fish. The tiny, vibrantly-colored, finger-shaped cleaner wrasses are widespread, common cleaners in tropical Indo-Pacific reef ecosystems, and many species of fish across the region are quite familiar with their grooming-focused diet. Not only do reef fish tolerate the little buggers coming up and nipping at their flanks (oxpecker style), but they will actively seek them out. Cleaner wrasses (along with other cleaner species) will typically hang out in specific areas on the reef that quickly become “cleaner stations” where scores of fish, of all taxonomic stripes, congregate to get all spruced up. The wrasses will bob and dance in a distinctive fashion to get the attention of potential “client” fish, and to advertise that the station is officially open for business. A client fish will usually signal to the resident shopkeep’ that they’re ready to be pampered by making a slow approach, articulating and tilting their fins and body, and opening up their mouth. The wrasse gets the message that this much larger fish is providing a meal, not looking for one, and it (and others) descend, darting around the outside, gills, and in the mouth of the client, clipping off whatever parasites they can find (along with some mucus and dead tissue as a bit of bonus flavoring).

“Is that…a tip jar? Are you serious? I’m literally feeding you two right now.”

Nasty, toothy, predatory fish like eels and needlefish, which can easily snap up the cleaner wrasse in a blink, patiently allow the world’s hungriest dental hygienist to get halfway into their throats to make everything sparkle. But, they trust that the benefits of having these eager exterminators going to town on their afflicted areas greatly outweigh the drawbacks of neglecting to take an easy meal. The clients trust they aren’t being taken advantage of, and the cleaner wrasses are confident they won’t be gobbled up while on the job…and this little symbiotic economy trucks on and on in near-harmony.

Well, kind of. Here’s the part where a third party throws a giant, douchey wrench into the mix.

Take a look at this cleaner wrasse:

This is Labroides dimidiatus, the bluestreak cleaner wrasse. It is common on reefs ranging from East Africa all the way out to French Polynesia in the South Pacific.

Now, look at this next fish, and look closely, because this fucker is the reason we can’t have nice things:

The fellow with the self-satisfied little smirk up there is not a bluestreak cleaner wrasse. It’s not even in the genus Labroides. Hell, it’s not even a wrasse. This fish is a variety of combtooth blenny, and therefore hails from a completely fucking different family from the cleaner wrasses. It’s known as Aspidontus taeniatus, the false cleanerfish, and as you may have figured out by now, is a convincing mimic of the bluestreak cleaner wrasse, just based on physical appearance alone.

‘But why mimic a cleaner wrasse?’, you may be thinking. Are the wrasses poisonous? Does looking like a cleaner wrasse allow them to escape predation? The answer to that is technically yes, but not for the reason proposed in this hypothetical train of thought.

Think of it this way: cleaner wrasses are popular. Among reef fish, they are highly-regarded. Trusted. Their particular set of skills and associated reputation has earned them the distinct privilege of unlimited access to piscine personal space. Surely, if another species were to disguise themselves as one of these pillars of the community, they would be able to get all up in larger fish’s business without issue. They could get as close as they wanted, and do whatever they wanted, all while never being hassled by predators.
While this initially sounds like a typical case of Batesian mimicry (mimicry to save one’s own ass from being eaten), and it mostly is, the false cleanerfish just couldn’t leave it at that. False cleanerfish, on occasion, exploit having the keys to the kingdom and decide to skim a little action off the top…and by that, I mean they tear chunks of skin and flesh out of their “clients” as a small tax for their delightful companionship.

Yes, this blenny capitalizes on the trust of its “clients” by not only being perceived as too damned important to be eaten, but also by periodically nibbling on these same fish like they’re big, living, traveling pantries.

False cleanerfish pull this off by managing to imitate the “wrasse wriggle” of their less bitey model in the middle of the cleaning station. When a client fish poses for some, er, oral service, the cleanerfish glides on over….probably giving itself a disquieting chuckle as it closes in. If the mood suits it (something that occurs perhaps one fifth of the time), the false cleanerfish then uses this golden opportunity to open its dainty little mouth, and drive a pair of hooked fangs up into an exposed sheet of fin from their seat in the lower jaw. This grand display of violent double-crossing apparently works best on juvenile client fish, as the adults have had a lifetime to figure out the subtle differences between the real deal and the filet-o-fraud that has a good chance of doing nothing but leaving behind a bloody, regret-shaped hole in a fin. It’s kind of like how the Internet looks very different to someone using it for the first time, and someone who’s been immersed in it for well over a decade: to a first-time user, sidebars and headers are full of a dizzying array of flashing and total convincing notifications of prize winnings you (somehow) are bound to receive (one click ahead!) and panicked, 5-alarm warnings about computer viruses you need to eradicate RIGHT NOW (…also one click ahead)….but to the Internet veteran, they’re savvy enough to recognize that these are all skeevy, predatory landmines littering a road to nothing but malware hell and digital herpes.
Many adult client fish have been burned by this used car salesman of the sea once or thrice before, and won’t let the little prick get close enough. But wide-eyed youngsters, not yet jaded and suspicious, are more likely to be successfully victimized.

Of course, fish don’t exactly write scathing Yelp reviews of their disappointing, painful encounters with these incompetent, overly-aggressive parasite-removers to tell other fish to beware and take their business elsewhere. Word doesn’t get around. So, if the false cleanerfish isn’t overzealous with the frequency of its biting behavior, there should always be a crop of innocent minors to teach, in a phenomenally direct fashion, that the world exists to completely fuck you over.

Then again, such client fish could have it worse. They could be damselfish. Specifically, damselfish that have to deal with the nightmarish psychological terrorism provided by the dusky dottyback (Pseudochromis fuscus).

Dusky dottybacks are found in the rich, vibrant, hyper-diverse coral reefs of the eastern Indian Ocean and southwestern Pacific and off the northern coasts of Australia. They, like all dottybacks (family Pseudochromidae), are diminutive, active predators that zoom around the reef and make a living fitting whatever they can into their insatiable jaws (usually crustaceans and tiny fish).
They also come in a wide variety of colors. Dottybacks in general exhibit eye-frying levels of super-saturated color (just take a look at the orchid dottyback) and there is great diversity in this coloration….but this tends to be between species of dottyback. Dusky dottybacks have distinct color morphs, ranging from yellow, to brown, to pinkish, to orange, and gray.
Conveniently, different color morphs appear to match up with the coloration of whatever species of damselfish (Pomacentrus) the dottybacks hang out around….which also tends blend in with the color of the coral backdrop in that area. Yellow damsels (like the lemon damselfish, Pomacentrus moluccensis) hanging out in yellow-y reef areas are accompanied by yellow-morph dottybacks. Brown damsels (like the Ambon damselfish, Pomacentrus amboinensis) in duller reef habitats also have brown-morph dottybacks loitering nearby, and so on. While blending in with the coral reef benefits both damselfish and dottybacks by making them less likely to be seen by big, fishy eating-machines and gobbled up like a handful of Skittles, the angle that the dottyback ends up working involves something far more sinister than just staying out of danger.

Really? The thing that looks like Steve Buscemi reincarnated as a betta isn’t trustworthy? You don’t say…

You see, being the same color as the coral around you is dandy and all, but from the dottyback’s perspective, the real magic is in looking like the damselfish that you keep company.

Dusky dottybacks blend in among their dim-witted damselfish schoolmates effortlessly. The damselfish accept their likewise-colored comrade as one of their own, and hardly pay the dottyback any mind. Sure, damselfish are notoriously territorial (towards their own species and others), but when their watery, slack-jawed gaze sees the dottyback in their midst, the damselfish may as well be looking in a mirror. The damselfish sees just another member of its tribe, completely failing to comprehend that a silent agent of Death has infiltrated their ranks.
The dottyback isn’t wearing its finest damselfish suit to conduct an undersea drug sting, or to romance a damsel-lady from the other side of the tracks (which is pointless, son; you come from different worlds! A damsel can’t love a dotty! She’ll eventually find out your secret, and while she can accept you for who you are, she’ll be crushed that you lied the entire time! It’ll end in heartbreak! HEARTBREAK!)….no, none of this.

The dottyback is there to stalk. To hunt. To feed. Not on shrimp, or mollusks, or a crop of sea squirts.
The dusky dottyback is there to kill and eat young damselfish. Yes, like some monster out of one of the more fucked up Grimm fairy tales, this scheming fish passes itself off as the adult neighbors (and, less likely, parents, aunts, uncles, etc.) of clueless damselfish children purely to get close enough to dine on their tender baby-flesh.

A 17th-century depiction of the patron god of dottybacks, Kronos, om-nom-nomming the everloving shit out of a baby

Dusky dottybacks hardly even register in the minute-to-minute perception of juvenile damselfish and their adult counterparts, and certainly aren’t considered a threat…until it’s way, way too late for the Pomacentrus pre-schoolers.

This cunning method that allows remorseless butchering of the small and naive, works out great for the dottyback, stealthily filling its belly, and increasing the average age of its host damselfish collective, in plain sight…but the mind-fuckery experienced by these young damselfish must be beyond compare. When the pedophagous Judas rolls into town, and you can’t trust any local adults to not fucking eat you when you aren’t paying attention, life must be a waking night-terror.

But wait, it gets better. The different color morphs of dusky dottybacks that target specific varieties of damselfish aren’t locked in. The dottybacks can actually change their color, and move back and forth between color morphs….allowing them to mimic and prey upon the kids of multiple species of damselfish. A brown-morph dottyback can turn into a yellow-morph dottyback (and vice versa), for example, in just a couple weeks after moving in next door to some yellow damselfish. Once enough of its brown pigment cells in its skin convert to yellow pigment cells to where it matches the color of its damselfish neighbors, the dottyback’s pride-n-joy predation success rate triples.

Two different species of damselfish on top; dusky dottybacks on the bottom, cosplaying their way up the food chain

The dottyback’s serial, infanticidal deception has been described as a strategy akin to what is employed by the specious lupine in the “wolf in sheep’s clothing” fable. However, given the plastic, color-changing element at play here, the dottyback is more like a wolf in sheep’s clothing that incrementally eats all the lambs in one flock….then takes off its sheep disguise, trading it for “cow’s clothing”….then sneaks into the next field over to switch to eating veal for a while….and so on…each new field with more and more missing babies…

It’s possible that the zeal of the dusky dottyback’s attacks on Pomacentrus pipsqueaks makes ditching the ruse and starting over in a new area dominated by another species of damselfish completely necessary. The dottybacks may be sly, but not all of their strikes are a success, and many juvenile damselfish escape. Considering that dottybacks attempt to nab their nubile prey really damned frequently, there’s a steep learning curve among survivors as to figuring out which grown-up in town is the one to stay the hell away from. It may be that after a certain point, every remaining young damselfish in the bunch has narrowly escaped death enough times that the effectiveness of the dottyback’s disguise goes to shit, and the devious bastard has to shamble out of the community and set up shop in an area nearby that is ignorant of its reprobate plans, like some kind of stereotypically shifty drifter or something.

Life can be shitty, and full of shitty people, but remember that in the ocean, the resident assholes take things to a level you’re (hopefully) never going to experience. Be glad that even though you may have paid far more for that TV you picked up at Best Buy (despite what the sales representative convinced you of) than it was worth, at least he didn’t go false cleanerfish on your ass and bite your arm and steal your wallet as well. Also, be content in knowing that even if your parents are being passive aggressive and manipulative, you’ll never have to worry about your mom actually being some ravenous psychopath in a mom skin-suit who tries to cannibalize you in the kitchen when you visit for Thanksgiving….dottyback style.

This post series will continue: Part 6 will focus on fish that disappear into their surroundings as completely as Gene Hackman did from the entire world…

Image credits: Intro image (blue hamlet), 2nd blue hamlet, blue chromis, cleaner wrasses servicing a rockmover wrasse, bluestreak cleaner wrasse, false cleanerfish, dusky dottyback (brown morph) (Paddy Ryan), Saturn (Kronos) Devouring his Son by Peter Paul Reubens, dottyback/damselfish set (clockwise from top left: Ambon damselfish, lemon damselfish, brown dottyback (John E. Randall), yellow dottyback (John E. Randall))

© Jacob Buehler and “Shit You Didn’t Know About Biology”, 2012-2015. 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.

Mesmerizing Marine Mimics: Decoys of the Deep

This post is the fourth in a six post series outlining the evolution of mimicry within the ocean realm. These posts detail various ways in which organisms may copy other organisms in appearance and behavior, and the evolutionary context for how these mimic-model pairings have come to be. The first entry in this series goes over some fundamental introductory concepts and definitions regarding mimicry in general.

Up until this point in this post sequence on mimicry in ocean ecosystems, there has been a focus on examples of animals that have evolved to strongly resemble another species, entirely and completely, in regards to appearance and behavior. But not every mimic goes for copying the whole shebang. Sometimes, just mimicking a specific body part of another creature is all you need to get the job done. Or maybe a tiny portion of your own body is sufficient to parrot the entire visage of a smaller species. I like to call this particular flavor of deception “fractional mimicry”, because instead of whole organisms mimicking other whole organisms, it is organisms mimicking other organisms that are in radically different size classes, necessitating evolutionarily ingenious use of specific regions of the body, or the resemblance of such regions. Fractional mimicry works through the broad manipulation of shape and color, and more importantly, the perception of shape and color in other organisms. I’ve already talked about a species that uses fractional mimicry earlier in this post series; the mimic octopus, which can use a subset of its tentacles to mimic a sea snake, or poke just its stalked peepers out of the sand to mimic a partially buried mantis shrimp. In the same blog post, I talk about a jawfish that is likely mimicking the tip of one of the tentacles of the mimic octopus, following the octopus closely as it moves across the ocean floor: this situation is an example of “fractional mimicry” as I’ve defined it, as the whole body of the fish is used to imitate a small portion of the entire octopus.

There isn’t any significant difference, from an evolutionary or general biological standpoint, between “fractional mimicry” and any other form of mimicry. To be honest, I just needed a good way to break up all of these posts. Grouping together species that share “fractional mimicry” or share the distinction of being fish mimicking invertebrates, or whatever, just makes my life easier. Sorry if that’s a bit of a disappointment.

So, let’s get to talking about “fractional mimics”; animals that achieve all the deception, but with half the work.

This fetching little fish is the comet (Calloplesiops altivelis), although due to its showy, expansive fins, it is also referred to as the “marine betta” (especially in the aquarium trade). It is found on tropical coral reefs across much of the Indo-Pacific, and shares its genus with one other less widely-known species. The comet is a type of longfin (family Plesiopidae), a group of small, predatory, vaguely grouper-like fish somewhat closely related to damselfishes (in regards to damselfish, think clownfish, like Nemo from Finding Nemo). They are also thought to be cleverly subtle mimics. ‘Of what?’, you may ask. A sensible, spotted handkerchief? A floating cutout of a Lite-Brite?

In reality, the likely model for the comet’s mimicry is a living critter, with a lot more in the way of bones, and eyes, and skin. And teeth. Lots and lots of teeth.

Those are some eely nice spots you got there! *nervous underwater laughter*

That distinguished, maculated fellow up there with the thousand-yard stare is a moray eel, in particular, a turkey moray (Gymnothorax meleagris). This species is found all over the tropical Indo-Pacific, and has a range that overlaps significantly with the comet. If you are going back and forth between photos and squinting at each, not entirely convinced that the comet, with all its disjointed, dangly fins, looks anything like a turkey moray outside of the spots, consider that the comet can throw out some remarkable acting chops in a pinch. When startled, the comet has a habit of straightening its larger fins, placing all of their edges together to eliminate gaps, and gives itself a diamond shape. It also takes its pelvic fins (the thin ones that hang below from the front) and tucks them at its sides, enhancing its new arrow shape. The comet then pokes its noggin into a hole in the reef, leaving its tail end out and exposed, conspicuous “eye” spot in full view. When it does this, the comet looks less like Chicken of the Sea and more like something much, much less appetizing.

I haven’t seen a 180-degree turn around this effective since Robert Downey Jr.’s post-rehab acting career.

It is thought that this unique behavior, combined with the comet’s bizarre shape and coloration, is indicative of mimicry of the head of a turkey moray, which wouldn’t be much of a stretch considering how often morays sit motionless in their holes, their heads poking out so they can keep an eye out on the rest of the reef like a bored, nosy, suburban neighbor. I’m calling this “fractional mimicry” because the comet would only be mimicking the commonly exposed head of the moray, not bothering with the rest of the body. This would also be an example of Batesian mimicry, where an organism passes itself off as a more dangerous or distasteful species.

And morays are most definitely an appropriately dangerous model for a mimic to emulate. Moray eels have an unsavory reputation among many divers as extremely aggressive death-noodles crafted directly from the barbarity and hatred of Poseidon himself, full of scorn towards the folly of Man. While tales of their unbridled rage towards all human parts soft and defenseless are a bit overblown, moray eels will bite when provoked or frightened…which usually happens when divers or snorkelers unwisely stick their hands and arms down what they think are empty holes and crevices in the reef. Morays are typically content to stay the fuck away from big, intimidating oddities like ourselves…granted we reciprocate respect of their bubble of personal space. With moray eels, encounters of the “tactile” kind are a recipe for trouble for humans and marine life alike…which is why the popularity of misleading videos like this that show anomalously tame morays acting like eager puppies begging for food and scritches concerns me; “playing” with almost all morays in the real world will invariably end in bloody disaster.

That “bloody disaster” comes directly from the moray eel’s fang-studded bite, the ferocity of which is, unlike their nasty demeanor, not at all exaggerated. While some species have flat, strong chompers that have evolved to crush hard-shelled prey like crustaceans and mollusks, many are ambush predators of fish, rocketing out of hiding spots in the reef and nabbing prey on the fly like that giant penis space slug in The Empire Strikes Back. Fish are particularly hard to hold onto if you don’t have hands, so these morays have mouths filled to the brim with long, sharp, recurved fangs that do a damned good job of holding their wriggling dinner in place. These teeth are also great at doing a shitload of damage to anything that isn’t food…like a human hand. Yanking the deeply embedded eatin’-end of moray eel off yourself causes those fish hooks to run through your flesh like a tractor ploughing furrows in a field. The end result is lots and lots of stitches, if you’re lucky. Google Image search “moray bite” if you have the stomach for photos of hands reduced to nothing but tattered, scarlet ribbons.
Moray eels have even more teeth on a pair of second fucking jaws that lurk further down their throat. These “pharyngeal jaws” are modified gill arches that shoot forward after a fish is snared with the upstream jaws and help drag the hapless victim down into Stomach Town. These marvelous evolutionary inventions only come into play during feeding time, not defensive measures, but any animal with a mouth within a mouth, like an honest-to-Christ Xenomorph, should still be kept at a safe distance.

These predators, with their bites-of-mass-destruction, command a great deal of fearful respect among coral reef animals big and small. Thus, it would make sense if the comet has evolved to mimic the most dangerous end of a turkey moray eel in times of panic.

However, it’s possible the comet may not necessarily be directly mimicking a specific variety of moray, or even morays at all. The position of the fake “eye” spot towards the rear of the body may confuse predators as to where the head of the comet actually is located. For reasons that should be obvious, a bite to the tail region is far easier to survive than a bite to the face, and there is precedence in organisms that appear to use a secondary “fake head” to deceive attackers (an example that comes to mind is Australia’s shingleback skink, a turd-shaped lizard with a tail shaped closely like its head).
The utility of the “second head” strategy may actually extend to the comet’s own predatory habits. Comets slowly stalk their prey, incrementally edging closer, often turning on their side, waiting until the prey item makes a critical avoidance error. Then, the comet lunges, mouth open, at extreme speed. The “eye” marking may be useful in tricking prey, letting the target think the harmful end of the comet is further away than it truthfully is, allowing for a much closer (and successful) approach/seizure.

When one part of an organism’s body is used to mimic another part of the same body, as would be the case in the comet and its “second head”, this is called “automimicry”….loosely, mimicry of one’s self. Many times, this is used to deflect the advances of predators, either by confusing the hell out of them on where they should even attack, or straight-up scaring the everloving fuck out of them. On land, there are plenty of examples of automimicry. Northern pygmy owls (Glaucidium gnoma) have eyespots on the back of their head that give predators the impression that they are being stared down with all the silent malice of a disapproving mother-in-law. Automeris moths have huge, menacing “eye” patterns on their wings that can flashed at predators, making the moth appear to be a much bigger, much more dangerous animal than it actually is, potentially giving the predator pause, and opening up a chance for the moth to escape. Other examples abound, in particular among the more vulnerable groups of winged insects.

An example of automimicry in the ocean comes from the appropriately-named four-eyed butterflyfish (Chaetodon capistratus), a name that is markedly descriptive, yet sounds like a school-ground insult of generations past.

“*snort* Nice glasses, dweeb.”

The four-eyed butterflyfish, native to the warm waters of the Caribbean and West Atlantic, isn’t, of course, actually bespectacled, or the proud owner of a second set of eyes. On either side of the base of its tail is a large, black, white-ringed blotch that resembles one half of a pair of eyes. When alarmed, the butterflyfish promptly turns its ass towards whatever spooked it, and gets the fuck out of Dodge in the opposite direction. It’s thought that these “eyes” mess with a would-be predator’s head, seeing as how many predators aim for the eyes and head when making a kill. It’s possible this would allow the four-eyed butterflyfish to outmaneuver its pursuer in an underwater chase, since the predator wouldn’t be totally sure which direction the butterflyfish would dart, disrupting all ability to predict where to aim and lunge forward.

It’s one thing to use your Mystique-ian powers of shape-shifting, visual deception to lull prey into a sense of false security, or to scare off attackers with an intimidating facade ala those plastic owl decoys used to strike dread in the hearts of obnoxiously-loud, frequently-shitting songbirds….but it’s another thing to use mimicry to get your food to deliver itself straight to your mouth…..


Dusk is settling on the reef, and you, a small reef fish, are beginning to stir. Your nocturnal habits have demanded you stay huddled with your school under a coral overhang for much of the day, but as night approaches, you flit about, anxious to venture out into the dark and feed. The blackness grows still, and it feels like a warm and familiar friend. Before long, you’ve decided you’ve waited enough, and you cautiously dart out into the open, your senses trained on your surroundings for any sign of food. You rise up in the water to scan a coral head for food.
Suddenly, you spot something with your huge, saucer eyes, your vision keen in the low light. Movement. You stop, waiting for the motion to once again reveal itself. Again, not far from you, perched high up on a rounded lobe of coral, a sign of movement, confirmed by your sensitive lateral line system, which detects minute vibrations moving through the water. You carefully approach. It wriggles side to side once more. It’s a fish! Your tiny, sesame seed-sized heart quickens its pace in excitement. Your unblinking gaze locks on the fish as it wriggles again. It doesn’t seem to notice you, rhythmically worming in place, nearly resting atop the coral head.
You slowly drift closer. It’s just small enough to fit in your mouth (which, notably, takes up about a quarter of your entire body)…which means its small enough to be a meal. If you’d had salivary glands, your mouth would be watering right now. You get even closer, close enough to pick out its red and yellow colors in the dark. It still doesn’t see you! Your heart races in anticipation. This is going to be too easy! You slowly angle your head towards its beady black eyes. You inch forward ever so carefully, readying yourself to strike. Your mouth is damn near touching its face. In your tiny fish brain, time slows, and you begin counting down your attack. Three. The muscles in your jaw flex. Two. Your gills beat one last time. One.
Then, out of nowhere, the fish’s writhing body goes as rigid as a balance beam. Before you can process what you’ve seen, you feel a terrible rush around you, and blinding pressure and pain on either side of your body. You panic, beating your muscular tail with everything your body has, but you stay in place, your head enveloped in suffocating membranes, and your flanks clamped in place with a vice-like grip. For several seconds you thrash wildly, and as soon as you stop, you feel whatever has captured you flex, and you get sucked deeper. It’s darker than you’ve ever experienced in here. You can’t breathe, and soon, you fade into your gastric tomb.


Were you a more intellectually-gifted animal, your last moments would have been full of realization that it was no delectable fish that you had pursued, and that you had been deceived into your death. You had the misfortune of having met your life’s end in the hungry, patient maw of the decoy scorpionfish (Iracundus signifer), lured in by the promise of sustenance.

By and large, the decoy scorpionfish is pretty normal by scorpionfish standards. Scorpionfish (family Scorpaenidae) are a very large and diverse group of fish, mostly made up of ambush predators that lie in wait for prey on the ocean or reef bottom. Most scorpionfish spend most of their lives not moving, attempting to blend in with their surroundings. Smaller fish or crustaceans that stray too close are sucked into their huge mouths through the vacuum caused when scorpionfish open their mouth faster than you or I can even see. Many species of scorpionfish also have potently venomous spines on their dorsal, pelvic, and anal fins, which are, as you can imagine, incredibly useful defensive weapons. A famous, and slightly more ambulatory representative of this group is the beautiful, highly-venomous, and notably invasive lionfish (Pterois). A closely-related family, the stonefishes and ghoulfishes (Synanceiidae), as a group, are the most venomous fish in the world, with some species with stings implicated in human deaths. Like its relatives, the decoy scorpionfish, found on reefs all over the Indo-Pacific, is a bottom-dwelling, stagnant, patient predator, adorned with venomous prickles along its back, a set of lightning-fast jaws, and a face only a mother could love.

Pictured: The deadliest strawberry-and-creme dessert on the reef

What makes the decoy scorpionfish unique among its brethren is that weird band of yellow stretching across the webbing on its dorsal fin. While it looks like a traffic safety reflector, or like someone recently assaulted the fish with a highlighter, its purpose is far more devious.

That little orange and yellow streak is a lure for attracting small, predatory fish to right above that big ol’ ravenous Dyson of a mouth. Lots of other fish use lures to convince prey to come closer. A good example are frogfish and anglerfish (order Lophiiformes), which use vaguely wormy bits of flesh that they jiggle frantically like we would a piece of yarn in front of a cat. However, the decoy scorpionfish’s lure is way, way more sophisticated than the glorified skin tag nightcrawlers used by anglerfish. What do I mean? Well, take a closer look at that front dorsal fin; the part that sticks up like the mast and sail of a ship.

Photo: John E. Randall

How about now? No? That’s fine, I have a video:

Yeah. That lure, with its little “eyes” and “mouth” looks exactly like a small fish. The spine sticking up in the middle even looks like a goddamn dorsal fin! This is no half-assed bit of glowy, spaghetti jigger bait that just keys in on and exploits the stimulus response of prey fish. This lure looks like it was handpainted in an artisanal studio, and is equipped with markings that imitate the body and head of a fish in side view with mindblowing accuracy. The ruse is made all the more powerful by how the decoy scorpionfish broadcasts the presence of the lure. When luring prey, the black “eye” expands slightly in size, and the scorpionfish makes the “fish” “swim” by snapping the first two dorsal spines side to side. This makes the membrane-bound spines further back do “the Wave”, which mimics the wriggling tail and body movements of a fish. This is more than sufficient to garner the curiosity of hungry passersby. All they have to do is get a little too close….and then….WHAM! Sucked down the gullet in one or two gulps. Curtains. Grim Reaper. A locker belonging to a Mr. Davy Jones. You get the idea.

The decoy scorpionfish uses a form of “fractional mimicry” in the reverse sense of the comet, where a small portion of its body resembles the whole body of another animal, rather than the other way around. This is also a case of “aggressive mimicry”, which is sort of the inverse, in a way, from Batesian mimicry; the mimic looks either falsely harmless or enticing, rather than falsely dangerous or off-putting, assisting predation or other types of interactions that benefit the liar at the expense of the sucker. An example of aggressive mimicry that is incredibly similar to the tactics used by the decoy scorpionfish comes from Lampsilis mussels, which use an exceptionally convincing fish-shaped lure to draw larger, predatory bass in close, facilitating parasitism of their clueless target.

This post series will continue: Part 5 will focus on fish that use mimicry to engage in some of the most manipulative, sociopathic behavior under the ocean….

Image credits: Intro image of butterflyfish, comet, turkey moray, comet in defensive position, four-eyed butterflyfish, decoy scorpionfish #1

© Jacob Buehler and “Shit You Didn’t Know About Biology”, 2012-2015. 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.


Mesmerizing Marine Mimics: Sea Slug Style

This post is the third in a six post series outlining the evolution of mimicry within the ocean realm. These posts detail various ways in which organisms may copy other organisms in appearance and behavior, and the evolutionary context for how these mimic-model pairings have come to be. The first entry in this series goes over some fundamental introductory concepts and definitions regarding mimicry in general.

The previous entry in this series tackled fish that masqueraded as their flippity-floppity boneless distant cousins, generally to keep themselves from getting devoured by one of the endless multitudes of hungry mouths that tirelessly dart back and forth underneath the waves. The entry before that looked at fish that mimic other fish as part of the same evolutionary strategy. It’s worth mentioning that while I really like fish (I study the things, for Christ’s sake), not every bit of mimicry in the ocean involves gills and fins. Plenty of invertebrates (the perhaps less-than-charismatic things like worms and mollusks) in the oceans also engage in mimicry of other species. Sometimes, just like in the last entry, these imitations can jump across to completely different phyla (a major organizational grouping of life right below “kingdom” (like the animal kingdom, Animalia) and above “class” (like Mammalia, which includes mammals within the phylum Chordata)). It’s also important to consider that the phylum to which all vertebrates belong, Chordata, is just one grouping compared to a shitload of so-called “invertebrate” phyla…like thirty of them (the exact number depends on who you talk to…there’s plenty of taxonomic/phylogenetic disagreement to go around). Familiar, cute vertebrate critters like pandas and cats and goldfish and parakeets get a lot of attention, but in reality they make up a tiny sliver of animal diversity. The vast majority of the animal species on planet Earth are “invertebrates”…a commonly thrown out figure is something like 97% of all animals. In light of this, focusing specifically on some gooshy guys for one entry in this series seems only fair. I guess you say I’m…throwing them a bone….or something.

One group of invertebrates that is deserving of focus in the context of marine mimicry are the nudibranchs (pronounced “noo-dee braynks”). Their name means “naked gill”, which refers to their unique respiratory system. While they are regularly referred to as “sea slugs”, nudibranchs represent just one large taxonomic group of marine-living “slug” (the other groups include things like the solar-powered sacoglossans, a member of which is the “sea sheep” that everyone was losing their shit about a month or two ago, or the huge, ink-squirting sea hare, which is part of lineage distinct from nudibranchs). To reduce confusion on what variety of sea slug one is talking about, many folks refer to them by the shorthand “nudis” (pronounced like one would for “nudies”…although taking care to distinguish between things like “nudi photographs” and “nudie photographs” in casual conversation is STRONGLY RECOMMENDED).

Nudibranchs are nested within the Phylum Mollusca, which contains notoriously slimy, muscular, and often tasty animals like squid, octopus, clams, and mussels, along with snails and slugs. They are also “gastropods”, which are a class of mollusks commonly equipped with a muscle-bound sliding “foot”, and include everything from abalone to your typical garden snail. Nudibranchs make up a modestly-sized branch of the gastropod family tree (which is MASSIVE, with at least 60,000 species), but their 2,000 or so species are found in essentially every marine habitat, from shallow reefs to the deep-sea. They are called “slugs” due to their lack of a shell, but the land-lubber “slugs” that keep terrorizing your lettuce plants under the cover of night are far more closely related to terrestrial snails than they are to the maritime mollusks at hand; nudibranchs are not particularly closely related to either domestic variety of gastropod. The majority of species are remarkably delicate and tiny, growing only to about the size of a fingernail, but some are burly even by gastropod standards, like the Spanish dancer nudibranch (Hexabranchus), named for its gorgeous red colors and elegant swimming style reminiscent of a flamenco dancer, which can occasionally reach the size of a watermelon. The one pictured below, found here on O`ahu a couple of years ago, is significantly smaller.

Photo: Jake Buehler

Nudibranchs are renowned for their bizarre, alien appearances and explode-in-your-face colors. Honestly, these things are like extraterrestrials ala Avatar meets three hours into a balls-to-the-wall mushroom trip. There are blue dragon nudibranchs, which look like pipe cleaners designed by Dr. Seuss. There are variable neon nudibranchs, which appear to be fuzzy velvet posters that have come to life. Many are so intensely colorful they look man-made. The Hopkin’s rose nudibranch is pretty much identical to those unnerving, pink, moving, Koosh ball things in Jim Henson’s 1982 film The Dark Crystal:

But let’s be honest, everything in that movie is unnerving. Remember the landstriders? *shiver*

The white-lined dirona looks like the ghost of a feather boa, and the highly-venomous blue glaucus is the size of a nickel and glides through the open ocean like a six-winged dragon made out of periwinkle glitter. Some nudibranchs look remarkably like the tiniest, fluffiest bunny you’ve ever seen. The diversity of otherworldly forms and color schemes among the nudibranchs is impressive, and much of this has its roots in the evolutionary biology of these animals. Being soft, mushy, and slow is no way to go through life in the ocean…in particular because your life will invariably be cut short. An easy meal doesn’t stay unexploited for long. Many nudibranchs have managed to maintain their svelte, silky, shell-less figures and avoid extinction by finding other ways of defending themselves. Some take toxins they acquire in their diet (often from sponges) and concentrate it in their bodies, becoming distasteful or outright dangerously poisonous to would-be predators. It is then thought that the insanely, psychedelic colors are an advertisement of their toxicity, telling the ocean at large that they ain’t nothin’ to fuck with. Others that feed on cnidarians (things like jellies and anenomes) can store their food’s venomous stinging cells, putting them in fleshy extensions that cover their backs like a forest of blistering despair. Nudibranchs are like Rogue…if she had to cannibalize other mutants to absorb their superpowers through the lining of her stomach.

Because of this habit of sneakily taking “you are what you eat” to the next, noxious level, nudibranchs are known to be mimicked by other species that do not have the capacity to become nasty-tasting or embedded with the biochemical Angel of Death.

Consider, for example, the pimpled phyllidiella (Phyllidiella pustulosa), a small nudibranch native to the tropical waters of the Indo-Pacific. It is a commonly encountered nudibranch, and is notable for regularly venturing out into the open in the middle of the day, a brazen act for a defenseless little slug nugget. However, the pimpled phyllidiella protects itself with toxins that it steals from the sponges it slurps up as it slowly slides across the coral reef. Fish in particular steer clear of this nudibranch, possibly because of its inherent toxicity, but also potentially because it resembles a blood sausage infected with small pox.

Fish will literally eat each other’s shit, but Mr. Clearasil “Before” Photo over here is just too icky.

It’s a winning evolutionary move for the nudibranch, and one that has been exploited by a completely different kind of soft-bodied co-inhabitant of the reef. This go-getter? Pseudoceros imitatus, often referred to as just the “mimic flatworm.” As a flatworm, it is a member of the phylum Platyhelminthes, and as I’ve described in the previous entry in this post series, this means it is nowhere near nudibranchs in the animal phylogenetic tree, and is a member of a group characterized by having internal organ systems about as substantive and fleshed out as Presidential candidate Donald Trump’s foreign policy musings. Actually, come to think of it, Trump’s socio-political ideas have a lot in common with parasitic flatworm infections; both propagate via mouths that have stayed open when they really should have been shut….and through liberal expulsion of feces.

Make America Eat Again…and Again…..and Again….Stop Asking Me Why and Just Put Food in Your Face, Goddamnit, You Ain’t the Only One Who’s Gotta Eat Around Here

Anyways, the mimic flatworm, unlike many other varieties of closely related flatworm that DO produce defensive toxins (and are themselves models for various mimics), is benign. Fortunately, it has evolved to look strikingly similar to the co-distributed pimpled phyllidiella, and has the same pale purple patches of zit-like bumps interspersed with black striping.

The mimic flatworm has even modified its sensory antennae (on the left side of the image) so that they better resemble the rhinophores (the blade-shaped “ear”-like structures on the heads of nudibranchs that act like noses/tongues, sensing chemicals in the water) of the model nudibranch, rolling them into upright, black cones. One brief, passing glance at this flatworm slithering out in the open by a passing fish (who had previously had a sorrowful run-in with a toxic pimpled phyllidiela) and it’s unlikely the fish would be able to tell the difference, and would continue on its way….and the worm lives to see another day.

Other species from other invertebrate phyla hop on the Toxic Pretender Train as well. Take, for example, the blackspotted sea cucumber (Pearsonothuria graeffei). It, like all sea cucumbers, is an echinoderm, a member of the phylum Echinodermata. The echinoderm umbrella includes familiar ocean creatures sea stars, sea urchins, sand dollars, bristle stars, and of course, sea cukes. Echinoderms are actually very closely related to our own phylum, Chordata, and have a number of bizarre distinguishing features, like locomotion driven by a complex hydraulic system and five-part radial symmetry (meaning that they have a body plan equally divided around a central axis, and thus have no right and left “sides” like we do). Sea cucumbers make up the echinoderm class Holothuroidea, and are closely related to their urchin cousins, but tend to be more leathery and sausage-shaped than little, hard, spiny balls. Sea cucumbers like the blackspotted sea cucumber are scavengers, methodically shuffling through the sandy bottom of the ocean, pushing whatever rotting particles they can find into their mouth with their scoop-shaped oral tentacles and extruding the waste (and lots of sediment) out the other end. When disturbed, many sea cukes (including this species) will shoot sticky strands of their own viscera at their assailant from their own asshole, which, you know, is kind of off-putting. These specialized organs are very roughly analogous to gills or lungs.

Yes, you read that right, sea cucumbers, when scared, have their breath taken away…but only because they shit themselves hard enough to blast part of their respiratory system out of their ass. I’ve heard of some fearful sharts in my day, but I’m pretty sure that takes the cake.

The blackspotted sea cucumber is a fairly standard “holothurian”, butt stuff included. Lethargic. Dull in coloration. Looks a bit like a plastic bag wrapped around a blackberry bramble. Or a mosquito-bitten colon. Or kind of like the alien from John Carpenter’s The Thing was trying to morph into a gherkin, but got interrupted halfway through by Kurt Russell.

“Well, looks like we’re in a bit of a pickle, aren’t we?” *lights flamethrower*

The blackspotted sea cucumber is mainly a tropical Indian Ocean species, but can also be found into the Indo-Australian archipelago (Indonesia, Papua New Guinea, etc.) and the Philippines. They can grow to about a foot in length, and precious few animals would dare attempting to eat them at their full adult size…I mean…that’s potentially a lot of weaponized butt-guts to deal with. So what does this all have to do with mimicry? Well, the young of this species of sea cucumber look very different from the adults.

Take a gander at the baby blackspotted sea cucumber:

It’s the thing that looks like a piece of bird shit.

You see, when the blackspotted sea cucumber is just a wee little sea cukelet, it has white (sometimes bluish) blotches interspersed with black lines, and large, exaggerated thorny projections capped with orange or yellow….very different than the brownish, spotted adult form. Attracting attention to oneself through in-your-face colors isn’t a good idea if you a dinky foodstuff like the young sea cucumber above….unless you wish to get something else across to your co-denizens of the deep. It is perhaps no coincidence that this unique, childhood appearance is remarkably close to that of a variety of nudibranch (one that’s actually in the same taxonomic family as the pimpled phyllidiella above).

This nudibranch is Phyllidia varicosa. It is also known as the “scrambled egg nudibranch”, which is possibly the most viscerally descriptive name for an organism I’ve heard since I read about dog vomit slime mold. And it’s an accurate description…er…sort of.

Behold, the Great Easter Turd

The scrambled egg nudibranch is, unsurprisingly, poisonous and gross-tasting as hell, and fish keep this guy miles away from their mouths once they realize what those pretty pastel colors are dressing up. While the blackspotted sea cucumber is a youngster, it is an effective mimic of these toxic nudibranchs, possibly providing itself protection from fish predators. However, as it eats, and craps, and grows larger, it vastly exceeds the maximum size of its nudibranch model…and the effectiveness of the mimicry breaks down….which isn’t helped by the gradual color change to more muted tones. Luckily for the blackspotted sea cucumber, while the young are helpless in the face of predators, adults apparently become toxic themselves as they age, so all is well in mature, drab post-pubescent sea cucumber land.

This post series will continue: Part 4 will focus on fish that mimic body parts of other animals, use parts of their own bodies to mimic the whole bodies of other animals, or use parts of their own bodies to mimic other parts of their bodies….trust me it’s not as confusing as it all sounds….

Image credits: Introductory nudibranch image, pimpled phyllidiella, tapeworm and intestinal roundworm background image for Trump/Tapeworm 2016 composite, adult blackspotted sea cucumber, juvenile blackspotted sea cucumber, scrambled egg nudibranch

© Jacob Buehler and “Shit You Didn’t Know About Biology”, 2012-2015. 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.

Mesmerizing Marine Mimics: Fooling Across Phyla

This post is the second in a six post series outlining the evolution of mimicry within the ocean realm. These posts detail various ways in which organisms may copy other organisms in appearance and behavior, and the evolutionary context for how these mimic-model pairings have come to be. The first entry in this series goes over some fundamental introductory concepts and definitions regarding mimicry in general.

A fish that has evolved to mimic a completely different, potentially entirely unrelated species of fish is relatively impressive. It is a testament to the power of natural selection, this honing and whittling down of a creature so that it may converge on the same exact external form for the sake of protection or the easy procurement of food.

But fish all have the same overall “blueprint.” Paired fins, vertically oriented tail fin, eyes in the front, big, snappy mouth, gills behind the eyes, generally sleek and muscular…there are a number of distinctly “fishy” features that evolution doesn’t fuck around with too much. This sort of basic body plan of a taxonomic group is sometimes down as a “bauplan” and its sort of the generic physical shape and scaffolding with which a given lineage of organisms ends up modifying as different branches break off and try out different tweaks and strategies. The “bauplan” for a motor vehicle, for example, is basically four wheels with tires, a broad cabin for passengers resting atop the rolling chassis, windows, engine, headlights, perhaps a trunk in the back. Anyone can tell you that there are many differences between a Chevy Camaro, a Subaru Outback, and a Hummer, but all of them are superficial when you consider the motor vehicle bauplan they all share. Similarly, the alterations and adaptations associated with the evolution of mimicry in these fish are limited by the constraints generated by their overall body plans. A fish can only fake it so far, and imitating another animal with the same bauplan is completely within any developmental constraints.

But there are fish that manage to step outside the “vertebrate box” when it comes to pulling a fast one on their ocean community. There are some fish that are mimics of invertebrates; spineless, squishy, squirmy things that they haven’t shared a common ancestor with for well over 550 million years. These fish convincingly pass themselves off as things that aren’t even remotely built the same way, all through some clever innovation through the prism of evolution.

The stately gentleman above is a dusky batfish (Platax pinnatus), native to the tropical reefs of the West Pacific, ranging from Australia to the islands of far southern Japan. Batfish and spadefish (family Ephippidae) are beefy, disc-shaped, herbivorous fish found in the warm waters of the world. Most have very large, symmetrical, pointed dorsal and anal fins that, when extended, give them a distinctly triangular or arrow-shaped profile. Some species are of interest to sport fishermen, like the Atlantic spadefish (Chaetodipterus faber).

These imposing swimming silver dollars are bound to make an impression underwater, but if you ever came across a juvenile dusky batfish, you may not know it….because they, much like Jaleel White of Family Matters / Urkel fame, look absolutely nothing like their post-pubescent selves.

What the fuck is this? It doesn’t even look like a fish. It looks like a piece of one of Guy Fieri’s tacky bowling shirts came to life.

While this little guy’s high-contrast orange and black style may make him look like he was created by the Tron: Legacy design team, it is thought the odd appearance was crafted by evolution to serve a specific purpose.

You’ll note that Mr. Halloweenfish up there deviates from the adult form in more than just that vivid orange trim. Juvenile dusky batfish are shaped completely differently: they have long, elegant, flowing fins with jagged, broken edges, and a tiny head with small facial features that disappear into the sea of black scales. These fish are more thin, membranous fin material than actual meat, and appear like they’ve been carefully flattened with a rolling pin.

It turns out that baby dusky batfish share their ocean with another animal that looks remarkably similar, and it ain’t a damn fish.

Fig.1: Not a fish

At first glance, this may look like a fancy-shmancy, elegantly-riffled chocolate and orange-flavored cookie, but I can guarantee you wouldn’t want to put this thing in your mouth. In actuality, this is an orange-margined marine flatworm (Pseudobiceros periculosus), a native of tropical reefs throughout much of the Indo-Pacific. Flatworms make up the phylum Platyhelminthes, and are among the simplest bilaterally symmetrical (meaning they have two sides that mirror one another, opposed to multiple sides that mirror one another around a central point, like a sea star or a jelly) animals on the planet, lacking specialized organ systems commonly considered important by creatures like ourselves; respiratory and circulatory systems are completely absent, for example. The most familiar flatworms in the human world are parasites like tapeworms and flukes, but in the oceans, particularly on coral reefs, there are big, free-living species that swim and crawl all over the place. Many of them sport brilliant and beautiful colors, like the orange-margined flatworm above…typically to warn predators that they are toxic, taste like shit, or both.

So, mistakenly thinking P. periculosus is a delicious product of Pepperidge Farms would likely result in you aggressively spitting, scrubbing your tongue, dry heaving, and generally having an awful time.

It is thought that the young of the dusky batfish have evolved to look like poisonous and distasteful flatworms like P. periculosus (or P. periaurantias or P. affinis, other black species with bright orange margins). As full grown adults, these fish are powerful, fast swimmers, and rely on their athleticism and (in some species) habit of schooling in massive, closely-packed groups to evade becoming dinner for bigger, toothier fish. But young fish are small, solitary, and vulnerable, and trying to pass as a bitter, noxious item that predators stay clear of is certainly a workable survival strategy.

To enhance the quality of their flatworm impression, juvenile dusky batfish do more than just look the part. These fish do “the Worm”, but instead of drunkenly flopping all over the floor at your friend’s wedding reception, they take the dance a little more seriously, gracefully undulating their fins like a woman wearing a long, flowing dress. They move slowly while doing this, hovering just above the bottom in an attempt to mimic the beautiful, billowing swimming style of a marine flatworm. They will also swim on their sides to better match the “flat” shape of the worm.

This deceptive tactic is shared across the entire batfish genus (Platax), but the young haven’t all evolved to target the same model. The longfin batfish (Platax teira) have young that appear to mimic rotting leaves, as does the young of the orbicular batfish (Platax orbicularis). The juveniles of these species in particular hang out close to shore in brackish, sheltered mangrove thickets….which drop plenty of leaves into the water for them to blend in with. Platax batavianus, the humpbacked batfish, have young that show off stunning black and white stripes with long, fan-shaped fins, but as far as know, no one has offered a potential model for the mimicry likely exhibited in this batfish. Personally, I think the young fish, with its striping and conspicuous wing-like fins, looks like it could be mimicking a small lionfish….which are armed with a marvelously, debilitatingly painful venomous sting, and are therefore a more than worthy model to emulate to keep away hungry predators.

There are a number of other fish that have a big, strong, independent adult phase, proceeded by a childhood spent cowering next to the reef and trying to convince fleet after fleet of humongous submarines passing overhead, each propelled by a stomach that is never full, that they aren’t on the menu.

For example, there are fish of the genus Plectorhinchus. These fish, members of the “grunt” family (named for the sound they make when grinding their teeth together), grow to be longer than a man’s leg and are powerful, muscle-bound, predatory fish. Plectorhinchus fish root around in the sand and rubble to uncover and crunch down on invertebrate prey like crabs or worms, and are immensely aided in this effort by their giant, voluptuous, puckered, sensitive lips….which has led to their common name, “sweetlips.”

Looks like these charmers just heard about the Kylie Jenner Challenge.

But long before these guys are putting their DSLs to work near the top of the food chain, roving the seafloor in intimidating, ravenous gangs, they spend their awkward early years trying to be something they’re not.

One species, the harlequin sweetlips (Plectorhinchus chaetodonoides), found in the coral reefs of the Indian and west Pacific Oceans, makes a particularly dramatic transition between its elementary school form and its full-on tax-payin’, job-havin’ adult form. The leopard-spotted adults are shown in the photo above. The babies (below) look like a Holstein fucked a guppy and dressed up the resulting child like a flamenco dancer.

Pictured: a yearbook photo from the harlequin sweetlips’ totally embarrassing “nemo phase”

These little spotted buddies are solitary and stay near the shelter of the reef. It isn’t until they mature, trade in their polka dots for a classy suit of fine spots, and graduate out of their size bracket and lower rung in the reef food chain that they become the confident, shrimp-crunchin’ machines I told you about. But until then, much like the juvenile batfish, they keep alive by mimicking what is thought to be a poisonous flatworm or sea slug. I’m not aware of a specific model that’s been proposed for this species (or the other varieties of Plectorhinchus, which have similarly small, billowy young with coloration that looks very different than the adults’), and it may be that it looks vaguely “flatworm-ish” or “sea slug-ish” enough to do the trick.

What is apparent is that harlequin sweetlips juveniles have evolved a combination of visual cues, color patterns, and killer dance moves that are immediately called into action at the first sign of a potential predator. They make exaggerated swimming movements, flopping their entire body back and forth wildly, letting their broad, flaccid fins articulate with each dramatic folding of the fish’s body. This loosey-goosey undulating is something suspiciously similar to what something without a spinal column might do….something like a flatworm….or a sea slug (specifically, a brightly-colored nudibranch). They’ll also often point their noses down, and wriggle their fins and tail back and forth in a nearly stationary vertical position, further improving the ruse. Predators figure the twisting creature near the bottom of the reef is likely just a toxic blob of culinary disappointment and go about their errands, and the harlequin sweetlips lives through another day.

Poisonous flatworms are apparently one of the more successful choices for a mimic to model themselves after, because the list of wormy, pancake-like juvenile fishes is long. Another fish that appears to take the Platyhelminthes path is the white-blotched sole, Soleichthys maculosus, found in the tropical waters of the West Pacific and northern Australia. Soles, along with flounders, halibut, and plaice, make up the “flatfish” order of fishes, Pleuronectiformes. Like their common name suggests, flounders and their kin (in contrast to what depictions in certain Disney movies about mermaid minors with a hoarding problem might have you believe) are literally flattened, living their adult lives spread out across the seafloor, grotesquely compressed, like a submarine steamroller came on through while they were taking a nap. These pavement huggers typically use camouflage to blend into their sandy, pebbly surroundings, or burrow just under the most upper surface of the loose bottom substrate. But the white-blotched sole, especially in its youth, is an anti-conformist, and its black background is splotched with white, and its fins are bordered with bright orange. This coloration pattern is blatantly similar to that of a poisonous species of marine flatworm (and close relative of the proposed model for the dusky batfish juvenile) that shares its range with the sole, Pseudobiceros scintillatus.

Ugh. I got bleach spots all over my nice black washcloth.

While some flatfish are somewhat well-known for producing their own distasteful secretions (like the Red Sea moses sole (Pardachirus marmoratus), which excretes a milky fluid containing pardaxin, an effective, toxic predator repellent), the flamboyant white-blotched sole is very edible. Because of this, its mimicry must be convincing. Air tight. It’s not enough to look like a flatworm from a distance (being flat already gives you a leg up in that regard), you have to fall into the role head over heels and really sell the whole damn thing, soaring your method acting skills to Daniel Day Lewis-ian heights.

Young white-blotched soles completely alter the way they swim (much like the dusky batfish and the harlequin sweetlips), channeling their inner invertebrate, as can be observed in the video below from The Blenny Watcher:

When flatfish move across their two-dimensional environment, they kick off the bottom with a thrust of their tails and glide like a living frisbee to another spot to settle down, keeping close to the bottom like a hovercraft, moving swiftly with rapid strokes of the tail and back edges of their fins. But the white-blotched sole in the video doesn’t do that. No. This little guy cautiously and methodically scoots along the bottom like someone trying to covertly edge themselves closer and closer to the door so they can escape an awkward, under-attended house party without being noticed. Like I’ve said before, it’s hard to show definitively that mimicry is occurring, but when behavior matches up with appearance like this, it’s pretty convincing.

With all this talk of baby fish pretending to be flatworms, you’d be forgiven if you thought that was the extent of cross-phylum mimicry in the ocean. Adult fish are known to try their hand at this kind of deception, and with very different organisms. Flatworms are easy, if you think about it; decked out in radiant colors, and with a fairly basic body shape and no complex structures to imitate, they are also found commonly in the more productive reefs. Poisonous flatworms are an obvious “choice” for a model. But there are more creative options out there.

Consider the frogfish. This family of fishes (Antennariidae) is kin to the famous deep-sea anglerfishes and monkfishes (large, ugly critters regularly fished in the North Atlantic). Like the rest of the taxonomic order to which they belong, frogfishes are ambush predators, lying in wait either buried in sand or perched on a rock or coral head for a small fish to cluelessly stumble into the range of its lightning fast jaws. Frogfishes also typically use a wormy lure (called an “esca”) on their face that they jiggle seductively to entice a meal to come just a liiiiiittle bit closer. Most frogfish engage in a specific kind of mimicry known as “mimesis”, a type of camouflage that makes you look like your (typically living) surroundings. Different species of frogfish have evolved projections from their skin and patterning that makes them blend into their surroundings; from backgrounds like sponges, to seaweed, to coral, frogfishes are really fucking good at disappearing in plain sight. When you actually look at them, they are basically chubby wads of used chewing gum with fin “arms” and a face. Frogfish always look like someone just slapped an ice cream cone out of their hands and onto the ground.

“What the hell, man?! I was going to eat that!”

The disappointed three-time winner of the “World’s Fuzziest Peach Contest” pictured above is the striated frogfish (Antennarius striatus). It is an incredibly common species, and is widespread, ranging into every warm temperate to tropical marine body of water on Earth. Most of the time, they look like the individual above; like Carrot Top’s cousin that he keeps insisting lives “by” the ocean. But every so often, they look like this:

Gross. Look what Mittens hacked up again.

Occasionally, a completely black morph without any patterning shows up. These guys look like someone took a tangled hair plug from a shower drain and used it to decorate one of those black turds you get from drinking Pepto Bismol. This fish looks like it should be sultrily voiced by Tim Curry and plotting to destroy the Last Rainforest.

In the Philippines in 2005, these black morphs were observed congregating alongside a species of urchin. This urchin, Astropyge radiata, is nearly entirely covered in long, needle-sharp venomous spines that pack a burning sting…hence its common name, the “fire urchin.” As I’ve mentioned once before, getting stung by a venomous urchin is a less than pleasurable experience, and anything capable of inducing agonizing chemical rage like that is bound to be a good potential model for a mimicking species.
This case, where black frogfish are slowly shuffling alongside a herd of sea urchins, is, possibly, fairly unique in regards to sea-bound mimicry. If indeed the frogfish were associating with the urchins to better resemble one for its own protection (with the idea that larger predatory are unlikely to bite down on something that looks covered in toxic pokers), a “wolf in urchin’s clothing,” then this is sort of a new one for frogfish biology. This would be Batesian mimicry; when a species has evolved to look or behave similarly to another species that is harmful/dangerous/distasteful, garnering the mimic a level of protection. This is different than looking like a tuft of sea grass or a pile of rubble to avoid detection, because those are neutral objects…background elements. Batesian mimicry has the purpose of making the mimic look like it can cause more trouble than it actually can. It’s hard to tell if the frogfish are blending in with the urchins for their own protection, or for making their disguise towards prey more effective; as in, is this just good ol’ mimesis, since no tasty little fish would expect an urchin to be a threat? Urchins aren’t exactly known for lunging out of nowhere and snapping up fish faster than you can blink. It’s possible there’s three distinct forms of mimicry happening at the same time. 1) Batesian mimicry (frogfish looks like a venomous urchin, so nothing tries to fucking bite it), 2) mimesis (frogfish looks like slow, benign, herbivorous urchins, causing small prey fish to never suspect a thing), and 3) “aggressive mimicry” (frogfish uses lure to persuade dinner to mozie on over to its awaiting mouth hole). I’m not aware of any other creature on the planet that manages to be a lying, tricky, untrustworthy bastard in so many different categories.

You know, it’s funny, I always thought you were a fish….but now I know you’re a SNAKE.
Photo: Frank Schneidewind

If this is the case, there are some interesting evolutionary angles to consider, especially when you remember the black frogfish are just a single morph within a species. How often do these black frogfish and the urchins overlap with each other, and where? Does this opportunity for Batesian mimicry make the black morphs more “fit” than the other, more common, tan and yellow morphs?
Science noted this possible occurrence of mimicry for the first time only a decade ago, so there are still plenty of unanswered questions.

The striated frogfish may have dabbled in a diversity of mimicry methodologies, but there’s another animal in the ocean that has a repertoire of characters it can pull out whenever it needs to, and is a prodigal genius of targeted bullshittery; a masterful Kevin Spacey of underwater imitation.
I’m of course talking about the undisputed king of marine mimicry, the mimic octopus (Thaumoctopus mimicus). This small, wiry, normally white and deep brown striped cephalopod is found in open sand flats in the tropical West and Central Pacific, as well as around the Great Barrier Reef. Thaumoctopus is a bit of a dickish, overachieving curve-ruiner when it comes to mimicry, far and away surpassing the capabilities of any other animal in the ocean with at least a dozen different models it can mimic.

Here’s one mimicking a boastful smugfish (Phallocephalus elatus)

This Swiss Army knife of deceit can casually contort its body and long, trailing tentacles into whatever animal seems like the best option at the time. This is a video showing just a few tricks up its eight sleeves. Lionfish. Sea snakes. Mantis shrimp. Jellies. Crabs. Tube worms. Sea squirts. Sponges. Flounders. The list goes on. Thaumoctopus‘s CV is extensive enough to land it a spot on the cast of SNL…and to be honest, it might be a bit of an improvement.

“I haven’t seen this much ‘floundering’ since every skit that Kyle Mooney has ever been in. BA-ZING!”

The mimic octopus is impressive as shit, but, as I’m sure you, astute reader, have noticed….the mimic octopus is not a fish. I’m listing this mollusk here not to go over the minutia of its mind-blowing powers of duplicity, or to really talk about it much at all, as mimic octopus have been talked about plenty since their discovery in 1998. No, I’m still actually aiming to talk about a fish that mimics an invertebrate….an invertebrate that just happens to be the most adept and versatile mimic in the ocean.

To understand what I mean, you need to check out this video below from Luiz Rocha from the Cal Academy of Sciences, and featured here:

Behold, the antics of the black-marble jawfish (Stalix histrio), which appears to mimic the tentacles of an on-the-move Thaumoctopus, behaving like a ninth arm as it sticks close by. Jawfish, members of the somewhat recently-evolved family Opistognathidae, are vaguely blenny-like fish with big, blunt heads, large mouths, and narrow, tapered bodies. They are homebodies, and spend much of their time submerged in burrows defending their tiny territories. Because of this, jawfish aren’t all that great at the “swimming in the open” thing that most fish do. They are also quite itty-bitty, with no toxins, spines, or mace to protect themselves with.

Let’s be real here, the most disarming thing about the black-marble jawfish are those puppy dog eyes.
Photo: Dray van Beeck

It’s been offered by the scientists that first described this relationship that Stalix histrio has found a means to move out in the open safely and securely, by hitchhiking along yet another completely unrelated mimicking species in possibly the only known case of “mimic-ception” on Earth. Think about that. The mimic octopus is so powerfully talented mimic of sea life to grant its own protection, that a teeny species of fish has evolved to mimic it for its own safety. That’s how good at its job the mimic octopus is. I’m not entirely sure the jawfish isn’t hanging out with one of the mimicry greats on some kind of mimicry apprenticeship or something, and is seeking to learn the tricks of the trade from a mentor. The entire thing sort of feels like when there’s a fictional TV show existing entirely within the world of a fictional TV show. Nature shouldn’t be that meta. I’m not sure I can handle it.

This post series will continue: Part 3 will tackle mimicry among the spineless and slimy…

Image credits: Intro sweetlips photo, adult dusky batfish, juvenile dusky batfish, orange-margin flatworm, sweetlips adults, sweetlips juvenile, P. scintillatus, brown frogfish, black frogfish, mimic octopus, mimic octopus as flounder

© Jacob Buehler and “Shit You Didn’t Know About Biology”, 2012-2015. 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.

Mesmerizing Marine Mimics: Counterfeit Malicious Fish

This post is the first in a six post series outlining the evolution of mimicry within the ocean realm. These posts detail various ways in which organisms may copy other organisms in appearance and behavior, and the evolutionary context for how these mimic-model pairings have come to be.

In the human world, being a “poser” can have serious repercussions.

Well, at least if you are found out by those around you. No one appreciates a fake. A phony. A liar. A disingenuous, duplicitous slimeball. Someone who is, as a notably troglodytic hobbit habitually says, “false.” Someone who appears to portray themselves as something they are not tends to raise the hackles of anyone in their immediate social circle. Sometimes, the issue is a complete breakdown of trust, and an inability for anyone to take your word or feelings seriously. You become an actor. A poor one, one that nobody believes. Sometimes, the transparency of your guise just becomes annoying and exasperating. Like if you saw Little Dragon do a set “at Sasquatch one year” and that was the only time you ever saw them perform, before or since, but now all you do is talk to your friend about how much of a “huge fan” you’ve always been, even though I…I mean your friend…was listening to Machine Dreams back when you were still listening to Jason fucking Mraz like an uncultured jackoff….even though you didn’t know about their collab with Gorillaz, and when asked where they were based, you shat out something about “New York mostly I think.” IT’S GOTHENBURG, FOR FUCK’S SAKE. STOP ACTING LIKE YOU KNOW THINGS, JEFF, BECAUSE YOU DON’T.

….anyways, posers can rub people the wrong way.

But in much of the natural world, faking your way through life may be a great strategy to keep alive and produce lots of offspring. Any trait that gives you in edge in getting food, not becoming food, and making sure you can make lots of babies (which also can get food and not become food) is likely to proliferate in the population. Sometimes, this means using deceit, and looking and behaving like something you are not. When a species resembles another in behavior or appearance (or any other sense), this is known as “mimicry.” The organism that a mimic is imitating is referred to as a “model”, and importantly, mimicry only really works for the mimic if the model is found in the same area. Evolutionary biology is rife with examples, many of which are found in terrestrial ecosystems, and often involve insects…because, partially, there are likely millions of insect species on the planet from which instances of mimicry can evolve. There are swaths of moths that have evolved to resemble wasps, and the moths benefit by fooling predators into thinking they can deliver a painful, venomous sting. European bee orchids have flowers that look very much like the solitary bee Eucera, successfully attracting horny male bees, which then find themselves inadvertently dry-humping a cruel, floral-scented bee blow-up doll, all the while unknowingly satisfying the pollen transportation needs of the orchid. The chicks of the Amazonian cinereous mourner (Laniocera hypopyrra) appear to mimic a fuzzy, rust-colored variety of noxious caterpillar, which helps them not get harassed by hungry wildlife, but at the cost of looking like something that would scamper off the scalp of a particularly controversial 2016 Presidential candidate that shall not be named. These are just a fraction of the examples. In the history of life on Earth, mimicry has evolved over and over again, because, quite simply, it can really pay to pretend to be something you’re not.

Of course, since mimicry is a bit rampant on this planet, it’s perhaps not surprising that there are many examples in the ocean. By and large, marine organisms aren’t the go-to for examples of broad evolutionary and ecological patterns, mostly because they are less familiar and accessible than terrestrial lifeforms (seeing and interacting with marine organisms requires getting under the water or out on a boat, typically, which is far more difficult than just walking out into your backyard to see land-living counterparts). For this same reason, science is comparably in the dark about rather basic things about how ocean communities work that we’ve nailed down for terrestrial ecosystems long ago. Many details are missing, despite us being aware that the level of biodiversity in the ocean is likely nearly comparable to what exists on land. So, for this series of posts, I’m going to address some of what we do know about these tricky evolutionary dynamics that are going on in the relatively hard-to-access and hard-to-study briny deep. Frankly, insects have had their day in the sun…er….I guess somewhat literally in this case.

Look at the photo of the pair of fish at the top of this blog post. It may interest you to know that those two fish are not of the same species. Ok, you may nod at your computer screen, that’s possible. “Cryptic species” (species that are essentially morphologically identical to one or more very closely related species, but based on divergence at the genetic level, are wholly separate species) are a common thing in nature (probably more common than we give it credit for), and are certainly known in marine fish. But, this is not what is going on in this case. These fish are not close relatives, only differing in the slightest of genetic differences. They aren’t even kissing cousins, and in fact, they are on fairly different branches on the “tree of life.” These two fish are actually in entirely different taxonomic families. Within taxonomy, a “family” is a fairly large division, and organisms that are within the same order, but different families, can be separated by many tens of millions of years. One of these fish has evolved to look virtually indistinguishable from another species…a species that it hasn’t shared a common ancestor with in many millions of years….a quantity of time for its lineage to experiment, evolutionarily, with a multitude of different body shapes, swimming methods, dietary changes, etc. in parallel (but not together) with the lineage that eventually gives rise to its model. This is almost the equivalent of two classmates from high school meeting again at a 20-year reunion; at one point, their world experiences and who they were as human beings was relatively close, being peers, but the combination of time and divergence of experience has left them, at the endpoints of their respective journeys, wholly different, long since separated entities. The distance between the tines of the fork in the timeline of their lives is far greater at the tips than at the initial split. The mimic is far removed in evolutionary time from its model, and the inherently different path its ancestors have taken have left its mark on its biology…and yet it manages to be a maddeningly convincing copy.

How convincing? Well, I originally had planned on sharing a completely different photo that showcased both model and mimic side-by-side. In fact, I had it sitting in a photo folder for hours, and I had spent quite a bit of accumulated time looking at it, between scrolling up and down this page as I was writing this blog post once I had slapped it up at the very beginning of the entry, and seeing it in the folder itself. It took me an embarrassingly long time before I stopped and stared at this photo, squinted in disbelief, and conceded that I had made a mistake, and that the featured photo actually showed two of the same species of fish, and that…pathetically….not even the person writing a fucking blog post about these fish could reliably tell them apart.

Pictured: A pair of assholes that make me question my intelligence, eyesight, and sanity.

The composite photo above makes finding their differing features much easier (it’s basically one of those “spot five differences” puzzles), but this type of comparative scenario is about as ideal as it gets, especially compared to a grainy photo of entire school of these things, or in life/video, when these fish are flitting about.

The fish in the top photo is the model. It is a Valentinni’s toby (Canthigaster valentini), and is a variety of pufferfish (Tetraodontidae) also commonly referred to as a “sharpnose puffer.” This species is also called the “black saddled toby” or the “saddle puffer” in reference to the black bands on its back and sides. Tobies (genus Canthigaster) encompass nearly forty species, and are found in tropical and subtropical reef environments the world over (but with far more diversity in the Indian and Pacific Oceans). These fish are small by puffer standards, and often only reach a few inches in length.
On the bottom is the mimic that has evolved to resemble the saddle toby. It is the blacksaddle filefish (Paraluteres prionurus). Filefish make up the family Monacanthidae, and are found in warm ocean waters around the world. This species, unsurprisingly, has a distribution that mirrors that of its toby model, ranging from East Africa east through the tropical Indo-Pacific to Fiji, north up to southern Japan, and south to the Great Barrier Reef.

Pufferfish and filefish make up two families within the order Tetraodontiformes, which also includes other rather bizarre groups like boxfish, triggerfish, and the massive ocean sunfish. While this means that they are closely related within the grand scheme of fish evolution, these two families are separated by more than 60 million years of evolution, meaning that their most recent common ancestor may have been swimming in the oceans around the time the big, non-tweety bird categories of dinosaurs were snuffed out of existence. For some frame of reference, 60-65 million years is roughly how far you’d have to go back to find the most recent common ancestor of humans and aye-ayes. So yeah, these two lineages have had ample time to develop some very large physical differences from one another….yet the blacksaddle filefish does a fine job of passing itself off as a toby.

But why bother? Trying hard to look like something you’re not seems reserved for things like trying to be impressive on a first date, gliding past all your flaws for a job interview, and attempting to convince the pizza delivery guy that you really aren’t a sad, slovenly hermit who legit ordered an entire meat lover’s pie for yourself at 9 pm on a Friday. There must be a compelling evolutionary reason for this ruse.

And there is. Black saddled tobies are splendidly poisonous.

Tobies, like many members of the pufferfish clan (and the closely-related porcupinefish (Diodontidae)), embed their skin and organs with potent toxins, in particular saxitoxin and tetrodotoxin (TTX), the latter of which is a compound so aggressively neurotoxic that it has given puffers the fearsome reputation of being used to generate one of the most dangerous dishes in the world. These powerful poisons are an effective deterrent to becoming a much larger fish’s meal, and this, combined with the hallmark pufferfish capacity to inflate with seawater to several times their original size, makes black saddled tobies an unwise choice for a meal; if it doesn’t inflate in your throat and choke you, it’s bound to sicken or kill you following digestion. For this reason, most fish that share the waters with these tobies have either evolved to not see these fish as food, or have learned to avoid them through unsavory prior experiences. Black saddled tobies are an Untouchable caste on the reef, and this keeps them alive.

If you are small fish and you share an environment with a fish that predators won’t touch with a ten foot pole, being a copycat will end up having its benefits. This scenario, where a harmless species permanently cosplays as another harmful or distasteful species as a defense against a common predator, is a subtype of mimicry called “Batesian mimicry.” It is particularly well-known in insects, but it is also seen in this pair of fish; the filefish, without toxins of its own, exploits local predators’ aversion to small, white, diamond-shaped fish with black stripes and yellow tail fins by fitting this description to a tee. The filefish doesn’t actually need to be the coral reef equivalent of the ancient mystery Tupperware in the back of the office fridge that no one wants to eat, it just has to play the part. The blacksaddle filefish enhances this costume’s power even further by commonly shoaling alongside groups of its toby model. Some 5% of the fish making up aggregations of black saddled tobies are actually mimic filefish attempting to discreetly blend into the crowd.

As impressive as the mimicry is, there are still small ways to tell the two fish apart. The easiest way is to look at the dorsal and anal fins (the fins on the back and rear underside of the fish), which is actually a little surprising when you realize that both species have Saran wrap thin, transparent, hardly visible fins. In profile, you can see that the toby has narrow, oar-shaped fins, while the filefish has long, undulating fins that stretch a great deal down the back and along the underbelly. The ribbon-shaped fins of the mimic filefish are a component of its evolutionary legacy it hasn’t escaped in trying to imitate the black saddled toby. Another tell-tale sign that you are dealing with a filefish? A rigid dorsal spine, found in all filefish, that usually lays flat against the back to enhance the disguise, but when it is rarely erected, making the filefish look like a member of an undersea “Little Rascals”, it completely destroys the disguise like some kind of reverse version of Clark Kent’s glasses. There are some other minor hints as well, like how filefish generally have compressed, inflexible bodies shaped like an empty pita bread made out of leather, while tobies are a bit more like two Hershey Kisses fused together at their flat, wide ends. Of course, in profile view this diagnostic feature is nearly impossible to discern accurately. There’s also the presence of bluish stripes behind the eyes of adult male tobies, which are absent in their filefish mimics. If you think all these examples should make differentiation between the two fish easy as hell, give it a shot by watching the following video from The BlennyWatcher Blog; it’s not as easy as you’d think when the little bastards are all swimming around:

This model-mimic system is made more complicated when you realize there is potentially a second mimic trying to get in on the toxic toby action. Meet Plectropomus laevis, the blacksaddled coralgrouper, found throughout much of the tropical Indo-Pacific.

Weird. I feel like I’ve met you before…

The fish above is a juvenile, and is only a few inches long (conveniently within the size range of a toby). Adults can be nearly four feet long, and as they age, their markings deviate further away from looking like the black saddled toby (more yellow on the fins and face, thicker black stripes, etc.). But, when these fish are young, they look very similar to Canthigaster valentini. It is possible that they, much like the mimic filefish, are also exploiting the toxicity of the model toby, and the fact that predators don’t mess with things that look like these tobies.

It’s also possible that there’s an additional benefit provided by this mimicry. Blacksaddle coralgroupers are voracious carnivores, and spend their days stalking and snapping up smaller fish into their wide, extendable maws. Juveniles of the species are no exception. Tobies, on the other hand, aren’t exactly the terrors of the deep, despite their toxic defenses. Tobies have an unintimidating tiny mouth and beak (made out of fused teeth) used to prune tiny crustaceans and other invertebrates from the surface of rocks and coral, and are basically a derpy turkey baster bulb with eyes. Juvenile blacksaddle coralgroupers could also be using their decorative deception as a means of looking less dangerous than they actually are…like nothing more than a harmless, omnivorous toby…allowing them to approach prey fish (however, as far as I know, no one has documented this being an observable factor in feeding behavior for the coralgrouper). This “wolf in sheep’s clothing” variety of mimicry is called “aggressive mimicry”; it is imitation with the purpose of lulling a target into a false sense of safety, only to have that target learn that it is not at all safe in an abrupt and dramatic fashion. Aggressive mimics aren’t actually cognitively aware of their own deceptiveness. Rather, their mimicry is the result of selection for behaviors and appearances that positively impact fitness. Their craftiness is not driven by an actual conscious plan, because this would require the mimic to fundamentally be aware of the presence of the mind of its prey (and to be able to anticipate how it will respond to external events), and this is a capacity known to occur in only a precious few of the planet’s most intelligent species of animals…and, here’s a clue, one is reading this blog post right now.

I should also directly note why I have said that the juvenile blacksaddle coralgrouper is “potentially” mimicking the tobies. Mimicry is particularly difficult to “prove,” largely because it’s hard to disentangle two co-occurring species that look alike because one has evolved to look like the other, from two co-occurring species that look alike out of coincidence. Specific coloration patterns, for example, have evolved many times over the course of life on Earth, mostly because they can serve specific functions unrelated to mimicry. When two co-occurring species look alike and are closely related to one another, it’s also possible that their close evolutionary juxtaposition is more at play than anything else. In the case of the tobies and the filefish, the argument for the filefish’s conspicuous similarity to the toby being more than a coincidence is significantly bolstered by two things: 1) the modification of the general filefish body plan to look specifically more toby-like (when color AND form converge in the same direction, that’s a pretty good indicator that something very directional is at play), and 2) the fact that these filefish regularly school with the saddle tobies, enhancing the quality of the mimicry greatly. Usually a combination of traits, like coloration, body shape, movement, and behavior…all appearing to mimic those of another species…boosts any argument for a clear case of the evolution of mimicry.

Being a copycat runs in the family for these filefish, as the only other member of the genus (Paraluteres), its closest relative, is also a mimic of a species of toby.

The top photo is of the model, Canthigaster margaritata, also known as the pearl toby. It is endemic to the rich coral reefs of the Red Sea (meaning it is found there and nowhere else). Below it is Paraluteres arqat, also a Red Sea endemic species of filefish, which appears to be a mimic of the pearl toby.

These examples of Batesian mimicry are fairly simple. A single model with one (or maybe two) mimic species. However, there are instances where a single model species is surrounded by a cloud of mimics, all independently donning the ocean’s version of a leather jacket and shades to look far more badass than they are actually are.

Let’s play a game. Below is a grid of four fish photos; one of them shows a model species, and the rest are mimics. Can you tell which one is the real deal and which ones are posers? And no, the answer is not “that housekeeper lady, Alice.”

“….all of them had hair of gold, like their mother…”

This wasn’t a game you were supposed to win, because unless you are a fish nerd like me, you would have no way of answering that question. The fish in this image that all the others have, we think, evolved to emulate is the one in the upper left-hand corner.

What exactly is the name of this popular fish with all the die-hard fans copying his signature look? Say hello to Meiacanthus grammistes, the striped poison-fang blenny. They are found on sheltered coral reefs all across the Western Pacific, from Papua New Guinea/northern Australia and throughout the Indo-Malayan Archipelago, to the islands of western Micronesia and the Ryukyu chain near Japan. Blennies (fish of the suborder Blennioidei within the order Perciformes) in general are a varied group, ranging from gigantic kelp-forest forms, to diminutive forms that perch cautiously on coral heads, to things like the sarcastic fringehead, which has apparently decided that it’s Steven Tyler. Most blennies are a secretive and benign bunch, opting to park their elongated bodies on a rock or coral branch, or hide in a hole, trying to remain still to avoid detection by predators and patiently waiting for food to drift or walk by, often in the form of a small crustacean or fleck of plankton.

But the striped poison-fang blenny is not like most members of its family (the combtooth blennies, Blenniidae), and stays about as still and serene as an eight year-old stuck inside a library an hour after shotgunning one dozen Red Bulls. Meiacanthus blennies tend to be active swimmers, and dart around well above the reef bottom, doggedly protecting it’s turf from everything the general vicinity with all the confidence and righteous swagger of someone who just ran into their ex and saw just how unattractive they have become since the breakup. These torpedo-shaped, yipping “sea chihuahuas” may only grow to three inches long or less, so you’d think they’d be an easy little snack for a predator to snap up while passing through the neighborhood, especially considering how brightly colored so many species in this genus are (some of them look like they mush have shanked Jeff Bridges to flop out of the Grid and escape into the ocean, and others look a gas stove flame and brought it to life).

But they aren’t. In fact, predators won’t go anywhere near the angry little bolts of fishy lightning. It turns out those bright yellow markings and bold stripes on Meiacanthus grammistes aren’t just there to show how severely and fashionably punk rock these teeny hellions are, but primarily serve as a stern warning to the rest of the reef….a warning that says “I AM VENOMOUS AND I WILL BITE YOU. I WILL BITE ALL OF YOU.”

“I came here to chew bubblegum and bite faces…and I’m all done chewing bubblegum.”
Photo by Martin Klein of Bluevisions

Yes, blennies in the genus Meiacanthus are collectively, and colorfully known as “poison-fang blennies” for the very real fact that they have a pair of enlarged, sharp canine-like teeth in their lower jaw that has a groove on its front side that is connected to a venom gland embedded in the jaw below. These fish, as far as I know, are the only fish in the world to have evolved a venomous bite; venomous stings, in contrast, have evolved in many groups of fish (scorpionfish, stingrays, rabbitfish, weevers, and stargazers just to name a few).

The biting action compresses the venom gland, sending venom up the groove in the curved fangs, and straight into the flesh of whatever decided it wanted to have a bad day that day. Poison-fang blennies only appear to bite other animals in its environment as a means of self-defense, or in defending its territory, not for acquiring prey. Poison-fang blennies are partial to plankton, mostly. While the venom doesn’t appear to be very effective on humans (outside of the pain of being stabbed with a pair of tiny, blood-drawing daggers when getting a bit too close when attempting to clean the aquarium), possibly due to huge difference in size (envenomation may be made difficult due to the small size of the fangs, comparatively, and the sheer size of a human body might dilute the effect of the dosage injected) it apparently does the trick against just about everything around it in its natural habitat…because nothing dares to touch it. On the reef, the poison-fang blenny definitely has a bad reputation, and much the same vein as Joan Jett, this fish really doesn’t give a damn about it.

This nasty reputation is ripe for exploitation by mimics, and this is why there are at least three different species, all from distinct evolutionary lineages, all converging on the same strategy of acting like the friendly neighborhood MMA fighter with terrifyingly unresolved anger issues. From an evolutionary standpoint of these mimics, the striped poison-fang blenny isn’t a belligerent, piscean d-bag with a butterfly knife, but a go-getter worthy of shamelessly plagiarizing, an idol of sorts, the Most Interesting Fish in the World….

The mimics are, counterclockwise from the upper left corner, Petroscirtes breviceps (a non-venomous species of fangblenny in the same family as Meiacanthus), a juvenile Scolopsis bilineatus (the two-lined monocle bream), and Cheiliodipterus nigrotaeniatus (a species of cardinalfish). The fangblenny is a close relative of Meiacanthus, but the monocle bream and the cardinalfish are both in different, distantly related families.

But it doesn’t just stop with this particular species of Meiacanthus, several other species of poison-fang blenny have “inspired” a cluster of satellite mimics…many of them also different species of monocle bream, fangblenny, and cardinalfish. Hell, the juveniles of Scolopsis bilineatus look differently in different parts of their geographic range, having evolved to mimic whatever resident species of poison-fang blenny has set up shop on the reef. Say what you want about the monocle bream potentially taking their inherent lack of originality overboard, but that’s some “loconomics”, community-minded, sustainably harvested shit right there.

This post series will continue: Part 2 will delve into the select few fish who not only pull off looking nothing like themselves, but nothing like any fish in the sea….

Image credits: intro image of toby-filefish pair, toby-filefish comparison: toby / filefish, Plectropomus laevis, Red Sea toby-filefish comparison: toby / filefish, grid image: mimic fangblenny / Meiacanthus grammistes / mimic monocle bream / mimic cardinalfish, Most Interesting Fish in the World modified from this photo by Klaus Steifel

© Jacob Buehler and “Shit You Didn’t Know About Biology”, 2012-2015. 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.


Claws: The Ultra-Jumbo Class of Crustaceans

Last month, the U.S. media engaged in a bit of a kerfuffle over a particularly beefy lobster that had been pulled out of the ocean at the Bay of Fundy. At some 23 pounds and an estimated near-century of life on this planet, the king-size crustacean is a worthy subject of a perennial news cycle that manages to somehow focus on monstrously outsized shellfish. The Fundy lobster isn’t alone, and is one in a line of many other big buggy bastards from all over the world that have received attention by tipping the scales at 20 or 30 pounds or more. The reasons why knowledge of humongous lobsters eventually ends up being mass shared are because 1) it happens to be a slow news day, 2) photos with people alongside lobsters posed in forced perspective to make them look even larger are awesome, and 3) it’s damned impressive, considering the average lobster that makes it to Red Lobster’s Spectator Tanks of Inevitable Death is only two or three pounds, a fraction of the size of these animals.

This is great and all, but our planet is populated with entire species of crustaceans that reach strikingly, unexpectedly insane proportions as a part of their normal biology. Perhaps the most famous, and most recognizable of these is the Japanese spider crab (Macrocheira kaempferi), an unsettling, spindly, deep-sea demon that looks like the end result of the Slender Man impregnating a shrimp, and at their largest, can outweigh your samoyed and bear hug a Ford Focus.

“AHHH, what the hell! Sorry, sorry, sorry…I’ll make sure to knock next time!”

But there are other crustaceans slowly shambling about under the waves, along sandy beaches, or even in familiar rivers and streams that are strikingly massive, and get comparatively little attention, despite being some of the biggest, crustiest, clicky-clacky pinch-mongers around.

One of these is the Tasmanian giant crab (Pseudocarcinus gigas), a species that, as its name indicates, is found in the cool waters over the continental shelf of Southern Australia and into the waters surrounding the northern coast of the island of Tasmania (in particular, the Bass Strait, the ribbon of ocean that runs between the island and mainland Australia). As far as overall appearances go, the Tasmanian giant crab isn’t bizarrely constructed like its distant cousin, the Japanese spider crab. It looks very….well…crabby. Broad, oval, shield-shaped carapace splashed with red with creamy white underneath, a pair of clawed arms, a bunch of short, bendy legs, stubby, twitchy mouthparts and feelers…..pretty standard as far as crab features are concerned. Pretty standard for its closest relatives as well; Pseudocarcinus gigas is the only member of its genus on Earth, but other members of its family (Menippidae) abound, and are often referred to as “stone crabs” for their stumpy, rounded, boulder-like body shape (one of them, the Florida stone crab (Menippe mercenaria), is popular as human chow in some regions of the southern U.S. and Caribbean).

The thing that makes ol’ P. gigas stand out from the crustacean crowd is what’s inferred by its species name, “gigas“, which literally means “giant.” Pseudocarcinus gigas gets big. It gets really, scary big. How big is “scary big”? Let’s just say that if the Krusty Krab was owned by this brachyuran behemoth, Spongebob would be continually shitting into every literal corner of his pants.

“Keep those patties comin’, boy, or I’ll cut ye asshole to gullet! Yek yek yek yek!”

The biggest Tasmanian giant crabs can weigh as much as 30 pounds, and have carapaces broader than the wheels of many cars, which is more than a little fucking horrifying. I become sweaty and uncomfortable when something very similar to the thing I crack open and delicately serve with mayo, citrus, and greens looks like it could clip off my arm and beat me with it. Seafood has no business being that big. I mean, these Tasmanian titans can grow as heavy as a human 2 year-old….and when picked up, nearly as ornery as one.

“Auuuugh! Who do you work for?! Is it Silver? Captain D? Joe? Tell Joe I’ll splinter his femur AND his goddamned, precious Shack!”

By far the most bladder-emptyingly intimidating trait of Tasmanian giant crabs are their asymmetric claws, one small and one large, something they share with many other members of their stone crab family. One of their claws is a wicked, armored machine of mythic proportions, a bony cage harboring more rippling muscle than what graced the forearms of a heyday Arnold Schwartzenegger, capable of shattering snail shells and human hands alike….and then there’s the “big” claw. The “big”, right-hand claw is a ridiculous, Mephistophelean apparatus, massive to the point of being grotesque, like some kind of unholy, supernatural mutation. Like the crab got caught stealing clams from Ursula the Sea Witch’s garden or whatever, and she cursed him with some kind of unsightly crustacean elephantiasis as punishment. This claw is armed with preposterously elongated, sharp, black tips that arc across each other like the long, unclipped fingernails of old-school Chinese aristocrats. I’m convinced this outsized pair of meat hook scissors is limited to a single specialized function: carving into the bellybuttons of mortals and removing the very souls from their bodies.

When the Terror-crab asks for a light, you better damn well give that bastard your lighter. Don’t ask for it back. Just leave.

It is perhaps of little surprise that Tasmanian giant crabs are widely regarded to be, mass-wise, the second largest crab species in the world (right behind the Gaunt Sea-nightmare I outlined briefly above)…and that when the opportunity arises, people can’t help themselves from taking photos of these things wearing normal-sized crabs as hats.

If you’ve been looking at Captain Living-Compulsive-Masturbation-Joke up there and thinking that beefy, super-swole right claw would look better split open and dunked in warm garlic butter, then you’re in luck. Tasmanian giant crabs are quite edible and there’s a small-scale fishery of these crabs in Tasmanian waters. However, if you’re a Yank like me, and are hoping to swing by the local Costco and pick up a gut-busting quantity of fresh Pseudocarcinus gigas deliciousness (probably marketed as “Tazzie mammoth crab” or something ridiculous like that), you’re going to be pretty disappointed. The annual harvest of this species is very limited, export tends to be local in scope (basically the rest of Australia and into East Asia), and the boutique nature of the fishery tends to make the crabs expensive (like 50 bucks per pound)….and that’s a good thing. Tasmanian giant crabs, despite their girth, don’t really eat that much or that often, wandering across the muddy ocean bottom, grazing slowly on the occasional carcass, unlucky mollusk, or smaller crab or shrimp. This laid-back attitude towards getting enough food energy to develop means that they grow and mature very slowly. This makes them incredibly susceptible to overfishing, since they can’t replace their numbers quickly. Strict fishing regulations are, fortunately, in place to keep populations from getting depleted.

But, if you were to make a special trip to the northern shores of Tasmania to get your hands on some of that delectable, rare, sustainably-fished giant crab flesh…you could see the second crustacean on this list just by walking inland, up into the wet, thickly-forested valleys of the island. Yes, Tasmania is host to two exceptionally huge crustacean critters, and this one lives in freshwater.

Meet the Tasmanian giant freshwater crayfish (Astacopsis gouldi), which was also known as the “tayatea” to some of the aboriginal peoples of Tasmania.

“On my way to steal your girl…”
(all giant crayfish gifs generated from this excellent conservation-themed short film entitled “Looking After Our Rivers” by Mark Pearce)

These stout, black-shelled, stream-bound lobsters are far and away the largest species of crayfish on the planet. How big are they though? Try THIS big.

Hooooly shit.

Nope. Nope nope nope nope.

At roughly the same size and heft as your neighbor’s cat, Flufferbell, a full-sized, adult tayatea is not only the largest crayfish in the world, but also the biggest freshwater invertebrate, period, currently in existence. In the past, there were reports of these crayfish growing as long as a human leg and heavier than a holiday ham, but these days, most tayatea are considerably smaller…yet still massive and intimidating enough to look more like the aliens in District 9 than something thrown into a pot of jambalaya.

The Tasmanian giant freshwater crayfish is, unsurprisingly, found only on the island of Tasmania. Even more specifically, it natively inhabits only the lowlands in the wet strip of territory at the northern end of the island, and is limited entirely to the streams and rivers in this area that flow north into the Bass Strait (the same body of water where the previously outlined giant crabs are plentiful). However, in recent decades, this range has gotten even smaller, and now the Tasmanian giant freshwater crayfish is typically only seen in fragmented sections of rivers in the northern part of the state. In the past 50 years or so, this strange, lobster-sized crawdad has seen a 70% decline in geographic range and its estimated population size has plummeted to about one fifth of its former glory.

Astacopsis gouldi is as endangered with extinction as it is gargantuan…a direct result of a combination of human influences and quirks of this animal’s biology.

When it comes to having traits that would help ensure survival in a world overrun with smart, hungry, city-raising, forest-leveling, farm-tilling primates, evolution gave the tayatea the shit end of the stick. First off, these giant crayfish are little more than slow, placid, white, succulent protein encased in a mildly inconvenient crunchy wrapper, each one large enough to feed an entire family in a pinch. When large numbers of European colonists began to settle in Tasmania, it didn’t take them long to take advantage of the rivers that were chock-full of living, breathing embodiments of a Cajun restaurant owner’s wet dream. The crayfish were pulled out of the waterways as a delectable and easily-caught foodstuff for many decades by the European settlers, but the harvest wasn’t even close to sustainable. Not even in the ballpark of sustainability. Actually, it wasn’t anywhere near the county containing the street where the ballpark of sustainability is located. It wasn’t necessarily the volume of crayfish taken by itself that was the issue, but the fact that, for the second strike against their luck, much like the giant Tasmanian crabs, the tayatea are particularly vulnerable to overfishing (and for many of the same reasons). Tasmanian giant crayfish take forever to reach reproductive maturity. Most species of crayfish that are collected by humans for food take between one and three years from hatching to finding a crayfish that shares its goals and interests, settling down, losing track of what music is popular these days, and churning out a bajillion chitinous kiddies. But Astacopsis? Males take somewhere in the neighborhood of nine years to get their gonads up and running, while females take something like fourteen fucking years to reach reproductive maturity. This reproductive procrastination is not so much that tayatea are the Peter Pan’s of the crayfish world, stubbornly refusing to grow the hell up and make their mothers into proud (and finally satisfied) grandmothers, but that they are late bloomers; reproductive maturity in crayfish is typically tied closely to size, and tayatea grow incredibly slowly by crayfish standards, and therefore their entire developmental lives are stuck behind a bus on the scenic route. This leisurely growth rate becomes a problem when individuals are pulled out of the population at even a modest pace, because it doesn’t take much to outpace the crayfish’s ability to replenish their numbers. Slow growth and/or maturation rates are a major factor contributing to the population depletion in many other animals (an example that comes to mind are sharks; many currently threatened or endangered species can take more than a decade or two to reach reproductive maturity, and once they do, they may not produce many offspring at all in their lifetimes).

The third trait working against the modern, post-European settlement survival of the tayatea is also associated with how these crayfish make babies. Not only do female giant crayfish take as long as humans to reach reproductive maturity, but once they do, they spend their lives with as much libido as a panda on SSRIs. Females will only spawn every other year (in the autumn), and grip the fertilized masses of eggs underneath her tail and against her legs until the next goddamned summer. That’s right, tayatea eggs take a full nine months to hatch. Even after anywhere between two hundred and one thousand less-than-giant crayfish come into the world, they stick close to Mom for another several months. So, a mature, female Tasmanian giant crayfish spends half her time “pregnant” or babysitting, and the other half not breeding. Fifty percent of her time actively reproducing may not seem that low, but the key is the long period of time our aforementioned lady crayfish spends directly caring for or incubating her single batch of offspring for the two-year cycle. The strategy of Tasmanian giant crayfish keeping eggs and babies on their person for a year at a time is, normally, a fine one. Once at reproductive size, giant crayfish are too large to have any natural predators that would threaten the lives of their clutch. Platypus and some species of fish are known to prey upon younger crayfish, but the big, honking, bowling ball-sized full grown monsters can contently take their time raising up the next generation. Humans, however, have no issue catching and eating adult crayfish….payload of eggs and all. What is normally a perfectly adequate reproductive gameplan, evolved in relative isolation from large crustacean-eating animals, becomes a grave drawback as soon as humans and their appetite for literally anything remotely vulnerable are thrown into the mix.

Historically, it was primarily the swift and unregulated direct overconsumption of these crayfish, enhanced by their slow growth, maturation rate, and long gestation times, that led to their fall in numbers. Since 1998, the harvesting of tayatea has been entirely illegal (without a special permit) in Tasmania, and there is hope that their populations will rebound in coming decades as a result.

However, this species is still at risk of extinction from habitat loss. This is where their fourth unfortunate trait comes in; Tasmanian giant crayfish are, much like that one roommate you briefly had in college, completely unable to compromise on their ideal living conditions.

“No, Derek, I don’t care that it’s ‘Fruit Loop Friday’. Do you want ants? Because this is how you get ants, you weird little shit.”

Astacopsis gouldi is a picky, finicky bastard when it comes to what is and what isn’t acceptable real estate. The streams in which these crayfish flourish need to be shaded with lots of riverside vegetation, and be crystal clear and clean. Preferably, the water should be relatively cold with high oxygen content and negligible amounts of sediment. Basically, if they aren’t sitting in a creek that looks like it was poured directly out of a chilled Brita filter, they ain’t happy or healthy, and will probably die as a result. So, you may be thinking, just keep pollution out of the rivers, and they’ll be fine. What’s the big deal? Isn’t northern Tasmania not exactly a juggernaut of industrialization (which would allow for the opportunity for waterway waste pollution to be a major issue)? Well, there is habitat degradation, but it’s indirect. The cause is large-scale, clear-cut logging operations that occur upriver near the headwaters of these drainage basins. The rivers and streams become swamped with mud and runoff, which chokes out crayfish downstream. Reduction of streamside vegetation (sometimes from direct deforestation, but also as a consequence of flooding and erosion caused by upstream activity stripping the riverbanks of any absorbing vegetation) has the effect of removing shade, which causes the water to heat up past tolerable temperatures, and for oxygen levels to drop (since oxygen does dissolve as easily in warm water). A lack of large plants and trees near these waterways also takes food right out of the mouths of these regal crustaceans. Tayatea consume rotting wood (and the bacteria that grows in and on it) as a major component of their diet. Leaving streams bare, silty, and hot effectively takes away the habitat and food sources of giant crayfish to the point where they cannot adjust, and are simply driven out of that drainage basin altogether. On top of all of this, in lower elevations, habitat loss from humans setting up farmland and diverting water is another strike in the chest of this species. Roads and culverts create additional problems, as they make moving between streams and finding new or adequate habitat next to impossible. So, if you’re ever traveling around the majesty of northern Tasmania, pulling over in your car to gander at the sights and check your map, and you’re feeling just a little too happy with yourself…just think about how the paper map in your hands potentially got its start in a forest up in the mountains, now mulched down to the dirt, leaving scores of crayfish downstream starving, baking, asphyxiating, and disoriented in a milky, dark slurry that was once their pristine home.

If you’re wallowing in impotent self-loathing and the futility of appreciating biodiversity in a dying world clap your hands…

Recovery efforts for this biggest of crayfish are slowed and complicated by a number of factors. Many regions in northern Tasmania are too far gone to hold any hope as a place of reintroduction; the streams having been drained for agricultural purposes a major stumbling block. The majority of the remaining range of this species exists on private land, which is largely used for lumber and agriculture, unsurprisingly, and is largely unfit for tayatea, assuming any high numbers still exist there. The best hope going forward for the Tasmanian giant crayfish comes from the small pieces of protected forestland in the Tasmanian wilderness, immune from deforestation, but until a direct series of measures are implemented to target the preservation and recovery of this species via habitat preservation, it’s uncertain how long they can evade extinction. Effective management will likely require additional behavioral knowledge and population surveys to determine where and how efforts will have the greatest impact. In the end, this tug-of-war between resource development and the health of river ecosystems is very reminiscent to me, as a former resident of the Pacific Northwest, of the convoluted history of salmon and the introduction of dams used to generate hydroelectric power. But, whether or not dramatic actions on par with dam removal will eventually be employed to save the endangered tayatea remains to be seen. I’m cynical, mostly because in the case of the Northwest’s salmon, the fishery is of huge economic interest; protection of habitat is actually of direct human interest. Tasmanian giant crayfish are unfortunately a vulnerable evolutionary curiosity and cannot play the role of “widely-harvested foodstuff”. Perhaps a better comparison between this crayfish’s plight and a threatened critter directly catty-corner across the Pacific is the famously down-on-its-luck (and divisively protected) northern spotted owl, an animal directly threatened by logging and the encroachment of agricultural land, but without an immediately tangible economic benefit gifted to humankind through its continued existence.

It’s worth mentioning that while the Tasmanian giant crayfish is superlatively impressive due to its size, Australasia in particular has quite a bit to offer in regards to unique crayfish. Mainland Australia, Tasmania, and New Guinea are a global center of crayfish diversity, with more than 150 species of crayfish patrolling the brooks and rivers of Australia alone. In particular, one family, the Parastacidae, is diverse and widespread across Australia. The family is known only from the “southern continents” (Australia, South America, southern Africa, and Madagascar), having a “Gondwanan distribution” (referring to the supercontinent of Gondwana, which was made up of these southern continents plus Antarctica, breaking apart nearly 200 million years ago). The Tasmanian giant crayfish is a member of this family, as is another sizable crayfish, the Murray crayfish (Euastacus armatus). It is found through much of the lower stretches of the Murray and Murrumbidgee Rivers in southeastern Australia, and grows to lengths of over a foot, making it the second-largest crayfish species in the world, beaten out by its close relative from the island of Tasmania. It’s a pale-clawed, thorny creature that looks like it crawled out of a pixelated puddle in the Super Mario Bros universe. It, like the Tasmanian giant crayfish, has suffered range reductions and population shrinkage as a result of fishing pressure.

All the colossal crustaceans mentioned above are either primarily, or entirely, aquatic. Their immense bodies are supported by water, and when pulled to the surface, despite their impressive/terrifying appearance, they can do little more than weakly flip themselves on their back and wave their useless legs like an air traffic controller on barbiturates. They are fine-tuned, armored machines when submerged, but when they feel gravity’s full effect and the desiccating air on their gills, they suddenly have the grace and energy of a hungover vertigo-sufferer trying to haul themselves out of a bathtub.

However, one species of crustacean has looked at the shimmering ceiling of its watery world, girded its loins, and taken the landlubber life by storm. This crustacean is not only the largest terrestrial crustacean in the world, but it is also the largest arthropod (the taxonomic phylum that contains everything from insects to centipedes to shrimp) to skitter about in the dirt in modern times. They are known by many names across their geographic range, including ‘coconut crab’, ‘robber crab’, and ‘palm thief.’ In the Mariana Islands and Guam, it is known as ‘ayayu.’ In the Eastern Caroline Islands, it is called ’emp’, and in the Cook Islands, it is called ‘unga’ or ‘kaveu.’ All of these names describe Birgus latro, an animal that looks like a combination of evolution’s take on the chitterskrags from the Dungeon Siege games and something that I’m pretty sure plants nightmares in your brain by whispering ever so softly in your ear as you sleep.

“Sshh, rest your head, delicate, mortal creature. May your slumber be….fruitful.”

These terrestrial crabs are found widely across the tropical Indo-Pacific region, ranging from the island of Zanzibar off the coast of East Africa at the western edge of their distribution, through the Indian Ocean and the scattered islands of the West and South Pacific. Despite their wide range, coconut crabs are fairly rare in areas with large human populations, with their largest populations situated in isolated island chains and coral atolls out in bumfuck nowhere in the middle of the goddamn ocean. The reason for this is almost certainly because humans are eating these critters out of existence wherever enough humans establish and overlap with crab’s territory. In fact, it is thought that they, at one time, were also found on the Western Indian Ocean islands of Mauritius and Madagascar, as well as the Australian mainland, but that humans in these areas simply om nom nomed them into a state of localized extinction (it’s also curiously absent from the Hawaiian Islands for an unknown reason, and when one recently turned up wandering aimlessly through Honolulu just down the road from where I live, the public/media response was one primarily concerned with its invasiveness…although it’s also possible it existed here before Polynesian colonization).

Perhaps this ‘extirpation by digestion’ is understandable, considering that in the tropical island locales that these crabs are natively found, there isn’t much food to eat anyways, so local populations would force themselves to dare subduing and splintering open an alien horrorshow that looks more like a demon-possessed Pokemon than a meal. But, there must be some other reason humans would risk cracking open something that looks like it scrambled out of a fresh, mysterious, meteorite impact crater. There is. Coconut crabs are easy to catch, and, despite looking like they having nothing inside but the souls of thousands of missing children, they are, in fact, full of succulent, delicious flesh. Shitloads of it. Because, as I said above, they are really big. And, to drive home what it means when I say “largest land-living arthropod on Earth”, I’ve included this oft-shared image of a coconut crab forever enshrining a newfound appreciation for the good, normal, God-fearing, nocturnal, unsanitary, kleptomaniacal mischief of raccoons.

I’ll take squealing, furry balls of teeth and rabies over an honest-to-Christ living Ray Harryhausen creature effect, thanks.

Coconut crabs, at their largest, can have a leg span of three feet and weigh as much as a 12-pack of whatever alcoholic beverage you’ll need to pound down to deal with this information. If you’re visiting one of the areas where coconut crabs live, and you think you can avoid seeing one of these guys by just skipping the beach, well, I’ve got news for you; coconut crabs are fully terrestrial, can march their creepy asses several miles inland, and are surprisingly, terrifyingly nimble over open ground. Also, did I mention they can climb trees? Because that’s sort of a thing they are known for. Shimmy-ing your quaking knees up a palm tree is a pretty fucking futile escape tactic. But remember, if you’re thinking at this point that your god has forsaken you and that surely these abominations are the incarnations of Old Scratch himself, know that they are NOT one in the same; one is an ancient, uncaring reservoir of malice and betrayal, a twisted being descended from a regal lineage…and the other is Satan.

Well, at least one of them is a shiny.

Birgus latro‘s unsettling size and otherwordly, death-spider appearance has been acknowledged mostly by, admittedly, comparatively hysterical and easily-petrified Westerners for a while now (the people of the tropical Indo-Pacific that lived alongside coconut crabs largely regarded these animals as delicacies and aphrodesiacs). In particular, coconut crabs were forced into the consciousness of American life during the Second World War when Allied forces were scattered across much of the West and Central Pacific, and American soldiers came in contact with these armor-plated monsters on their remote island outposts. The impact coconut crabs had on these men can be seen in the stories and imagery that made it back home in the decade after the War. For example, this was a beast so unnerving, apparently, it inspired artwork (and associated tales of terror) featured in hypermasculine, vintage “men’s adventure mags” in the 50s, much like the George Gross piece below, which was featured on the cover of the November 1956 issue of Man’s Conquest. For context, this was a publication so devoted to stories of egregiously haggard badasses upholding Man’s glorious dominion over nature by shooting, spearing, roundhouse kicking, or otherwise dispatching a veritable zoo of inexplicably numerous and murderous wildlife that I’m half-convinced the magazine owes its existence to the ghosts of Teddy Roosevelt and Ernest Hemingway aggressively ejaculating onto a stack of blank pages. The 50s and 60s were….uh….a different time.

“Christ Almighty! These are the second-worst crabs I’ve ever had to deal with…next to the ones I got from that dame the last time I was in Tijuana with the boys!”

The coconut crab’s great size becomes even more impressive when you consider the evolutionary history of this crustacean, and all the truly unique adaptations and modifications to its physiology that have been driven by natural selection.

Birgus latro is literally one of a kind. There is only one known species in the coconut crab genus, and its closest living relatives might not be what you’d expect. Rather than its nearest kin being other big, brutish beasts like the other “giant” crabs and crayfish I’ve gone over earlier in this blog post, the coconut crab comes from diminutive stock. Coconut crabs are actually a variety of ludicrously huge, highly-derived, “homeless” hermit crabs. Coconut crabs are members of the family Coenobitidae, which includes a single other genus (Coenobita). Coenobita hermit crabs are notably robust and very capable land-dwellers themselves, but of course, the elephantine black sheep of the family takes this to a whole other level. The family resemblance is still quite there, and this is especially true when you pull down the coconut crab baby photos from the attic. Juvenile coconut crabs, following a larval stage in the ocean, are functionally the same as Coenobita hermit crabs. In their youth, coconut crabs hold onto their heritage tighter than a woefully misguided South Carolinian waving the Stars and Bars; they cover their soft hindquarters by retreating into, and carrying around, a snail shell. It is only after they have grown larger, too large for any shells or even coconut halves, that they forgo their protective training wheels altogether and start strutting about in a thick, desiccation-resistant carapace. I was in the Republic of the Marshall Islands (a Micronesian nation of coral atolls in West Pacific) earlier this year, and I saw a young coconut crab on a beach on Arno Atoll without even knowing it. At the time, I assumed it was a Coenobita species, but it was months later when I was looking at the photos and attempting to identify the species that I realized no native hermit crabs were a match, and the coloration was a dead wringer for a fledgling Birgus latro. The one I happened across was using an ill-fitting piece of plastic pollution as a shell, which should have tipped me off, considering that everyone knows that, of the two crab groupings, young coconut crabs have the inferior sense of fashion.

You’re wearing plastic? Really? Hydrocarbons are SO last season.
Photo: Jake Buehler

So, coconut crabs are just hermit crabs that hit the gym and creatine powder really hard and ditched the mobile home to grin and bear it out in the big, harsh, idyllic, balmy, sunny, white sand beaches. It’s worth observing that hermit crabs, as a group, aren’t really “true crabs” either. They belong to a division of crustaceans (an infraorder, in this case) called Anomura (meaning “differently-tailed”), whereas “true crabs”, which include all the crabs you are likely most familiar with (including the giant Tasmanian crab), are in the infraorder Brachyura (“short-tailed”). Other Anomurans include squat lobsters, mole crabs, and king crabs (which includes this star of Deadliest Catch). Anomura and Brachyura are thought to be “sister groups”, meaning they share a common ancestor more recently than with any other similar division of crustacean.

Outside of their size and libertine views on hermit crab domestic traditions, coconut crabs have evolved a number of traits that not only make their terrestrial lifestyle possible, but required. For one, coconut crabs have modified their gills into a brachiostegal lung, which consists of gill tissue with a high degree of surface area to allow absorption of oxygen from the air rather than from water. The setup, not unlike the interior workings of your own respiratory system, must be moist to function well. However, unlike you or I, the coconut crab doesn’t have a whole series of cavities and sinuses and tubes to facilitate the retention of moisture, so it uses a rather crude (but effective) method: wetting its legs in a puddle and stroking them over the convoluted lung tissue. Although these lungs need to be constantly spritzed, this doesn’t mean an adult coconut crab can breathe in water just as easily as in the air. Their branchiostegal lungs are indeed lungs, and a submerged coconut crab is guaranteed to drown. Adult coconut crabs are so incapable of dealing with water that after mating on land, the female carts around the fertilized eggs underneath her tail until right before they hatch, and when the time is near she makes a trip down to the water’s edge with the haste of someone hunting down a public restroom after a gastronomically reckless episode with a gas station burrito. There, she can wash her young into the surf at high tide while hardly getting wet.

Coconut crabs have a varied and entirely terrestrial diet, which, as you’ve likely guessed, includes coconuts. These crustaceans really can, and do, break through the tough exteriors of coconuts to eat the nutritive white flesh on the inside. It sometimes takes the work of more than one crab at a time, but they are more than capable of using their strong claws to strip away a coconut husk like you would feverishly denude a Kit Kat bar of its wrapper (and by you I mean me…far more often than I’m proud of). Breaking apart the inner core occurs in small pieces, and splitting the whole thing open can take days, but an animal with a brain the size of bouillon cube can do it with its bare hands and that’s more than I can say for myself. If coconuts aren’t already sitting on the ground, and a coconut crab is in the mood for some Mounds and piña colada action, the hungry bastard will summon its inner Sylvester Stallone ala Cliffhanger and clamber an incredible thirty some-odd feet up a palm tree to snip a coconut down for a snack. Most coconut crabs don’t bother to edge their way back down the tree trunk, and opt to just flop gracelessly onto the ground below, which doesn’t appear to harm them. Also, just a friendly reminder, getting hit with several pounds of falling coconut, or eight pounds of falling, giant fucking wanna-be monkey crab, can cause serious injury or death. While incredibly unlikely to ever happen, the coconut crab is, via aerial, kamikaze assault, theoretically the only crab on the planet that could (inadvertently) kill a human being.

All this being said, in reality, coconuts don’t make up the bulk of the coconut crab’s diet.

Its favorite food is….TV show hosts! Run Brian Cox! Run for your life!

Coconut crabs have a surprisingly varied diet. Much of their caloric intake comes from fallen and decaying fruit, but they also regularly seek out and indulge in carrion, as well as small reptiles, mammals, and even other crabs. Truthfully, if it’s stationary, or unwary enough to be captured…there’s a good chance that these guys are already on it. Their garbage disposal habits have made coconut crabs, to some, the potential reason why Amelia Earhart’s remains may have never been found; the idea being that if her plane went down over an isolated atoll, and she managed to survive long enough to make it to land only to die later, her body would have been consumed rapidly by coconut crabs. Some dubious records of a partial skeleton from the early 40s in Kiribati, along with other bits of evidence, have fed into the idea that this was Amelia’s final fate. But, it is far from settled, with much of the story’s claims of crabs carrying off and burying her bones like a pack of the weirdest dogs in the world not being supported by any behavioral evidence in these creatures.

As scary as coconut crabs are up close, in one-on-one combat, the worst they can inflict is a nasty, vice-like pinch. They, like every other crustacean in this list, is far more in danger of being boiled, broken, and buttered by humankind. Perhaps it is telling that even the largest, most physically imposing representatives of an entire taxonomic class are still outmatched by our species’ appetite, and that we have the ability to literally eat entire populations (or whole species) into oblivion. It would do us, and the world we inhabit, some good to be aware of this unbalanced power and privilege.

Image credits: Intro coconut crab image, Japanese spider crab, giant Tasmanian crab closeup, giant Tasmanian crab gif (clipped from this video from Eaglehawk Dive), giant Tasmanian crab with lighter (Paddy Ryan), man in cereal tub (Getty Images), coconut crab on forest floor, coconut crabs in trees, Man’s Conquest cover (George Gross)

© Jacob Buehler and “Shit You Didn’t Know About Biology”, 2012-2015. 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.

Venomous and Underrated: Paralysis Ticks and Undersea Pricks

This post is the second in a two-part series on particularly potent venoms found in organisms not commonly renowned for their chemical fortitude. Part 1, which explored the stings of ants and wasps, can be found here.

The fact that there are a number of hymenopterans (ants, bees, and wasps) that have particularly nasty venom isn’t exactly a shocking revelation; these insects are solidly associated with their aggravation-driven stings and their painful side-effects. The degree to which some of these stings can pack a blow may be not well-appreciated, but the general public consciousness is already quite unhappily familiar with how hymenopterans liberally dispense venoms into any and all soft, unguarded tissues like it’s their goddamn job. However, there are entire groups of animals that are worryingly, intimidatingly venomous that are hardly ever even thought of as being venomous in the first place. Yet, these animals have the same chemical gift that has brought infamy to spiders, snakes, and scorpions the world over…that same Midas touch….that is, if everything King Midas touched was suddenly gripped by unbearable, electric agony and shit all over itself in screaming, fitful anguish until it died.

The first of these are animals most folks hardly think about outside the contexts of disease transmission, things that might make the family dog very unhappy, and Leno-chinned superheros in sky blue spandex. It’s likely that only if you spend substantial time in rural areas during warm weather months does this parasite ever clamber into your overall awareness. Yes, I’m talking of course about the glorious, unflinchingly, universally revered tick.

Ticks are the notorious, unabashed gourmands of the arachnid world, partaking heavily and exclusively in the reddest of wines there is; blood. Ticks get all of their nutritional requirements from the blood of vertebrates, and require blood meals to produce offspring and to transition from one developmental stage to the next, ‘leveling up’ like Mario curb stomping a mushroom. To feed on this precious elixir, ticks have to somehow pump it out of their hosts. They do this by tearing open the outer layers of skin with paired cutting mouthparts, and by plunging their “hypostome”, a rugged, practically unbreakable spear-like component of their mouth, deep into the skin. “Spear-like” really doesn’t do this anatomical atrocity justice as a descriptor, actually. Scaled up to nightmarish, non-microscopic proportions, it resembles the depraved union of Klingon weapon and a sex toy designed by a cruel and angry god. From another angle, it looks like someone glued a hedge-trimmer on a mouth harp.

Although, it might need a little tuning. It looks a bit sharp.

Compared to things like mosquitoes and leeches, ticks aren’t nearly as gentle and considerate about making their non-consensual withdrawals from the blood bank. Rather than expertly piercing a blood vessel, and cleanly sucking up the payload through straw-like mouthparts, ticks employ a markedly inelegant strategy. The sharp mouthparts are used to saw into the skin horizontally, providing an access tunnel for the barbed hypostome. They sweep through and clear-cut tangles of tiny blood vessels like a weed-trimmer shredding a roadside thicket. The rent vessels spring forth with their delicious contents, and the flood generates a pool just under the surface of the skin from which the tick can slurp up its meal through the hypostome.

When the peckish parasite penetrates through the outermost epidermal layers of skin, that’s when the real fun begins, and the venom comes into play. Ticks are indeed venomous animals, and rely on a medley of saliva-bound toxins they inject into the wound site to keep the feeding process running smoothly. Tick venom is complex, with each component toxin targeting a specific physiological process, the multitude of them adding up to create a gestalt effect geared towards keeping the gravy train flowing into Tick Town, and the host’s body completely oblivious that something is amiss. Tick venom is very good at keeping the nutritive river running; anti-coagulants, thrombin inhibitors, small proteins that screw with platelet plug formation (a key part of clotting), and vasodilators (molecules that help widen the piping in your circulatory system) all make the host bleed like Russian royalty, growing the blood reservoir below the skin and allowing the tick to feed uninterrupted. The venom also has a whole host of anti-inflammatory components that work to shut down localized immune response to the bite and all the saliva being pumped in. These toxins are a molecular invisibility cloak, and allow the tick’s feeding to fly under the radar of the host’s immune system. This, in turn, allows the tick to guzzle on the good stuff, anchored in place, for a LONG time compared to other blood-sucking animals (we’re talking a week or more in some untreated cases). Female ticks are especially gluttonous, packing away ten times their original body mass in blood. At the end of a blood meal they, much like Marlon Brando in that 90s remake of “The Island of Dr. Moreau”, are left turgid and bloated far beyond any resemblance to their former svelte selves.

Left: Me before visiting Chipotle
Right: Me after visiting Chipotle

It is through their feeding and injection of potent salivary chemicals that ticks manage to serve as vectors for a multitude of diseases. More than a dozen disease-causing microorganisms (and growing) hitch a ride inside ticks and infect the animals they bite via their chauffeur’s venomous spit. Some of them are familiar…and horrifying; Lyme disease, Rocky Mountain spotted fever, and Colorado tick fever are just a few. Many of these illnesses are knock-you-on-your-ass debilitating, and for this reason, the real health concerns of tick bites don’t come from the venom itself, but from whatever bacterial or viral horrors were tagging along. Ticks are dangerous venomous animals in the same way that mosquitoes are, simply by being the filthiest, most pestilence-ridden vampires this side of an unregulated Transylvanian bordello.

“But hold on now,” I hear you protest. “What the fuck is this tricky-dicky bullshit? Wasn’t this post about ‘surprisingly venomous’ critters and not ‘surprisingly disingenuous list entries based on a technicality’?”

Well, take a seat, unabashedly displeased reader, and get ready to untwist your knickers, because there’s another aspect of tick venom that packs a punch well beyond the fact that the stuff is basically a pathogen soup. How much of a punch? Well, some species of tick have a bite that can induce a kind of paralysis so brutal, the absence of prompt treatment can be life-threatening. Yes, tick venom, in some cases, can make you go floppier than Charles Krauthammer’s face…and then kill you dead.

The condition is known as “tick paralysis” and is known from more than forty species of tick, from all over the world. Most of the time, tick paralysis is a concern mostly for animals; dogs, cats, and livestock like horses. Fido is far more likely than (most) humans to roll around in ticky areas full of long grass, pick up a shitload of bitey blood bags, and then carry on like nothing is wrong for many days later. Dogs don’t exactly pat themselves down for ticks after a blissful summertime romp in the wilderness, so ticks are more likely to feed for longer in an undetected state.

It’s actually that extended length of time blood-feeding that is crucial in the development of tick paralysis. Symptoms, for unknown reasons, really don’t start until the tick has been gorging itself on blood for at least two or four days. Partially for this reason, in the case of humans, the highest risk group for tick paralysis are young girls, since many of them have longer hair that easily obscure a feeding tick for a long while. Children in general are far more likely to contract tick paralysis (although adults can definitely be stricken down), perhaps partially due to their smaller size (which would make the paralytic toxin more relatively potent), or due to the fact that a squirrelly 8 year-old on a hiking excursion is virtually indistinguishable from the family labradoodle in regards to restraining oneself from barreling into a weedy, off-trail blood-sucker bacchanal.

The paralysis itself is as serious as a stroke, not the least due to the similarity of the some of the symptoms to, you know, the aftermath of an actual fucking stroke. The progression of effects from the paralytic toxin, apparently not released from the tick until at least two days or more into the feeding, start off as subtle. A weak voice here. An unsteady gait there. From there, things tend to get worse by the hour. The legs lose strength and buckle, eventually becoming paralyzed entirely. The paralysis ascends up the body, soon affecting the torso and arms. In a matter of days, a person afflicted by tick paralysis can go from vigorously traipsing through the brush, high on nature, to as limp as an overcooked spaghetti noodle. If the tick is not found and removed, the paralysis may continue to the point where breathing and heart rhythm is compromised. A sufferer with an unaided, frozen diaphragm is, obviously, not long for this world.
Many decades ago, back before more sophisticated public health awareness concerning ticks existed, and back when a much higher percentage of people lived out in rural areas, death by tick paralysis was more common than it is today. There are postmortem reports of ticks being found upon examination deeply embedded into the flesh of folks who had suddenly dropped dead from an unknown paralyzing sickness. The realization that an animal the size of a lentil could slowly and incrementally sicken and kill something as big as a human being must have been difficult to tackle.

Tick paralysis still occurs periodically in the U.S., and luckily, deaths are now very rare (although much more common in pets and livestock). So rare in fact, that when we even consider the hypothetical possibility of endogenously dangerous ticks, we have to turn them into humongous, squealing, alien monstrosities that terrorize a young Seth Green and a freshly-greased Clint Howard in a hilariously shitty 90s sci-fi/body horror flick like an army of murderous haggis:

One of the worst offenders for tick paralysis the world over is found in Australia, because of course it is. Locally, it is known as the “Australian paralysis tick” (or Ixodes holocyclus if you feel like treating this parasite with a modicum of respect and calling it by its true name). This species ranges all along the eastern coastline of the Australian continent and into Tasmania, frequenting dense, humid rainforests that characterize the region. It evolved to target large marsupial mammals as hosts; things like koalas, kangaroos, and bandicoots, but of course, humans and their furriest family members are also adequate substitutes as blood repositories.

During the first half of the 20th century, there were nearly two dozen recorded deaths in Australia from this species, a value that is, by the way, greater than deaths from more expeditiously venomous arachnids like the notorious funnel-web and red-back spiders in the same period. It was this particularly paralytic variety of tick that has inspired the most research into the causative chemical agent behind the venom’s effect, and has yielded the most information. Although, to be frank, we still know relatively little about how this venom works compared to other venomous groups of arachnids like spiders and scorpions. What we do know for certain is that once the tick is removed, the effect of the neurotoxic venom diminishes rapidly, and the paralysis can wane completely within only a day. There doesn’t seem to be much in the way of lasting effects, like you would see in the recovery period after a bite from a venomous snake or spider. You can think of tick venom as a very light, steady drip, introducing neurotoxin continuously, so that as long as the tick is in place and feeding, the paralysis builds over the hours and days. But as soon as the tick is unattached, the body expertly manages to break down whatever toxins were left behind. This is a very different system compared to most potentially fatal neurotoxic envenomations, which tend to rely on one or two injections of a catastrophic dose of venom, followed by the delayed effect on the target’s physiology. Getting bitten by a cobra, for example, is the neurotoxic equivalent of getting hit by a truck. The damage done is nearly instantly dire, and without prompt treatment, death is a near certainty. Tick envenomation is more like getting repeatedly pelted with whole cantaloupes; sure, it only hurts a little at first, but after many hours, the cumulative bruising and bleeding from hundreds of hard-shelled cantaloupe impacts can begin to take their toll. If the onslaught never ceases, then murder by melon is a very likely consequence. Tick envenomation is a regular trickle, not the firehose of single-incident destruction seen in most other venomous animals.

We also know of a small number of putative neurotoxins in tick saliva that may be directly responsible for the paralytic bite. They are known as “holocyclotoxins” and based on both the size of the compounds and the genetic sequence coding for the toxins, they appear to be very closely related to scorpion neurotoxins. There is some thought that these paralytic toxins are a hold-over from before ticks had evolved a parasitic lifestyle from spider-like, non-parasitic ancestors that would have needed potent neurotoxins in their bites to disable prey. Inadvertently killing your meal ticket isn’t exactly a winning strategy in regards to natural selection, so it’s unlikely that it has anything to do with parasitism, and more to do with an evolutionary line that is fundamentally steeped in significantly venomous ancestors.

Ticks’ venom, much like the venom of the hymenopterans I mentioned in Part 1 of this post series (like jack jumper ants and Philippine hornets), is still something that is actively, consciously, and maliciously injected. The hymenopterans have stingers, and the tick has its awl-shaped mouth; both tools that require a fairly direct decision to effectively wield. For example, no one gets stung by a wasp by accidentally bumping into the stinger. The wasp has to actively drive its stinger into a victim. But there are plenty of surprisingly venomous animals that are more passively venomous, allowing bold and naive attackers to make the mistake of doing the envenomation for them, adorning themselves with armor made of hypodermic needles full of biochemical napalm, primed and ready, capable of inducing horrific pain with the slightest pin prick. Stonefish and prickly, venomous caterpillars are among the creatures that come to mind. But there are others, particularly beneath the crashing waves of the tropics, that possess strong (perhaps unexpectedly so) toxins that they can unleash if someone were to unwisely place their hands somewhere they really, really shouldn’t.

Sea urchins are not the most huggable animals in the ocean. Close relatives of sea stars and sea cucumbers (they are all Echinoderms, a term that means “spiny skin”), they are characteristically blanketed in countless hard spines. Urchins exist as little more than a bony globe surrounding huge gonads, a small, but rugged set of teeth, a smattering of gummy tube feet, and a shitload of prickles, plates, and poky bits. Many of these porcupines of the sea tend to do alright against predators by just being tough, unappetizing balls of thorns. But some have incorporated venom right into their spines, and by doing so, become the most regret-filled meals since KFC’s “Double Down Dog”, a culinary abortion so grotesque that I’d tell it to go fuck itself if it didn’t look like it already had.

Oh boy! A post-coital flesh wang and fried chicken labia pairing, with cheese lube included!

Living in Hawai`i, and spending a lot of time in the water around the coral reefs here, I am familiar with a few varieties of these venomous urchins. One of them, the banded sea urchin (Echinothrix calamaris), is a fairly common sight on the reef, their striking white and black ringed spines waggling slowly from their protected position in holes and outcrops. In the Hawaiian language, they are called “wana” (pronounced ‘vah-na’), and are the sole reason I wear protective boots or tabis before I ever wade into the water along a rocky shoreline.

Or why I don’t just reach under rocks or overhangs without checking first.
Photo: Jake Buehler

Wana have a set of spines interspersed with their long, banded ones that are shorter and thinner and far more brittle. These spines easily puncture skin and break off under the slightest amount of pressure, and are finely barbed, allowing them to introduce a flood of venom as they stick stubbornly in you. Last year my girlfriend got to experience the venom of the banded urchin quite literally first-hand, when during a bit of volunteer work leading elementary school children around an exploratory look in the intertidal, she picked up what she thought was one of the harmless species of urchin. It was not a harmless species of urchin. Not even close. The price for her mistake was a quiver of purple to black lances thrust deeply into her finger, making her look like she strayed too close to a mechanical pencil factory during a hurricane.

Ow ow ow ow ow ow ow.jpg
Photo: Christie Wilcox

After pulling out the spines, the intense pain in her finger quickly faded, and the swelling and pain decreased for about a week. But the urchin wasn’t done with her yet, and a few weeks later, pain and stiffness returned to the disfigured phalanx before finally abating for good.

While the hot fire poker pain of a run-of-the-mill venomous urchin spine seems bad, trust me, in the world of venomous urchins, it can get a LOT worse. Far exceeding the potency of the banded sea urchin are the flower urchins, which consist of four species in the genus Toxopneustes. They are found in shallow reef habitats in the tropical and subtropical Indo-Pacific, ranging from East Africa, through the Indo-Australian Archipelago, and throughout the Pacific and across to the coastlines of California and Central and South America. Do not be fooled by the deceptively benign common name. The “flower” moniker refers to the urchin’s numerous flower or cup-shaped “pedicellariae” structures, which are typically small and claw-shaped in other urchins…bear in mind that its scientific name, Toxopneustes means “poison breath”, so that should be a solid indication that it is a dangerous sea beast devoid of warmth or joy. Also, it is those very elegant, delicate-looking “flowers” that administer this urchin’s toxic ruination.

“Eeeeeevery roooooose has its thorn….”

Every suction cup-shaped pedicellaria is equipped with three sharp claws, derived from the grasping appendages more commonly seen in pedicellaria in other urchin species, and looks like some surreal marriage of grappling hook and toilet plunger. Each recurved fang connects to a venom gland. When disturbed, the cup of the pedicellaria snaps shut, like a Venus fly trap, and the fangs overlap with one another, turning the round tip of the pedicellaria closed and more triangle-shaped. The fast and forceful collapse of the pedicellaria tip plunges the three fangs deep into whatever unfortunate fleshy bit (like a human hand, for example) that triggered the reflex. The snapping action automatically opens up a valve in the stem of the claw, and the urchin sends a stream of venom right into the puncture site, like some kind of vindictive, ferocious sea cauliflower.

The most violent of violets, the carnation of carnage, the aster of diasaster…
Daffodil? More like daffo-KILL.

Things tend to go downhill rapidly after that. The claws don’t relax and release on their own, and the stalks for the venomous pedicellaria are brittle, so even a passing brush can not only land you with a dozen “bites” from the world’s most venomous version of those cheap, sticky suction cup ball toys, but the grip of the cups can cause them to break off and stay stubbornly stuck to your skin, where they continue to pump in cascades of burning venom.

This is a pretty goddamn awful situation to be in, because Toxopneustes venom, by urchin standards, really doesn’t fuck around. There appears to be two principal toxin components of the venom nailed down at this point. One of these is peditoxin (comprised of pedoxin and pedin, the former of which, on its own, causes sedation, coma, convulsions, and death in test animals), which, once purified from flower urchin venom, fairly easily kills mice in low doses by inducing a kind of anaphylaxis-like shock. In addition to this, another toxin, contractin A, is known to induce contractions in smooth muscles. It’s not clear how contractin A actually plays out in a whole, living animal (the study used tracheal smooth muscle isolated from a rodent), but it’s important to remember that smooth muscle is found in some fairly important places….like in the walls of major blood vessels, or in the respiratory tract. Having your circulatory or respiratory system seize up, especially while out swimming in the ocean (where a sting is most likely to occur) can be a one-way ticket to Davy Jones’ locker.

And indeed, there are a handful of reports of people drowning after an unfavorable encounter with a Toxopneustes urchin, supposedly caused by the intense flood of envenomation symptoms: the disorientation caused by the electric pain, combined with respiratory distress, muscle weakness, and wide ranging numbness and paralysis, which together overwhelm the water competency of the victim. However, no purported “deaths-by-urchin” have been definitively confirmed. That being said, it’s best not to test this one if out and about on the reef. The peak of flower urchin envenomation effects are apparently short-lived, with the worst pain and paralysis ceasing within the first half hour of the sting, but one must remember that it only takes seconds to minutes to drown…something not exactly helped when the ability to breathe, tread water, and think clearly are shot to shit.

If the harsh sting of the Koosh Ball of Agony wasn’t unexpectedly dangerous enough for a creature that looks more like a dog’s squeaky toy than a real animal, then get a load of the last entry in this post; an animal that appears so benign and motionless that it registers in the brain as more plant or mineral than anything else.

Imagine you’re on the vacation of a lifetime, SCUBA diving off the equatorial coasts of Indonesia’s island of Sulawesi. You are some forty feet below the surface, surrounded by the serenity of some of the richest and most diverse coral reefs in the world, the only sound your rhythmic breathing and the rush of bubbles from your regulator. Towering coral pinnacles flank your gliding path along the reef, great, complex, stony structures of purple, yellow, and navy blue. Clouds of minuscule, neon green damselfish undulate and contort around their stationary place above a coral head as you approach. The water is a warm 82 degrees, and isn’t much cooler below the surface, so you are only wearing a short-sleeved wetsuit. You catch a glimpse of something big, fast, and deep blue blazing off to your right. It’s a humphead parrotfish. You signal to your dive buddy and follow cautiously, watching it slow down and maneuver around a field of broad, olive-yellow, branching corals. It disappears through a hole, but you know it has popped out the other side. You know you need to rise up above the wall of branching corals in front of you, so you ascend slightly, attempting to peek over the edge. You can hear the parrotfish feeding just on the other side, so you need to move as slowly as possible, so you don’t scare it away. You ready your camera, and reach out to steady yourself by grabbing onto one of the thicker regions of the weird, smooth, lacey coral in front of you. You stop, remembering that Kent, the divemaster, had specifically directed you and your buddy to not touch any wildlife if possible…ESPECIALLY not the sensitive corals. Kent is a 42 year-old white man with dreadlocks, a DMB logo arm tattoo, who talks incessantly about his recent “juice cleanse” and the “spiritual awakening” he had volunteering and (inadequately) constructing school houses in Uganda. Fuck Kent, you think to yourself, and firmly grab onto the coral with your bare left hand and pull your weightless body upwards.  You snap some amazing photos of your parrotfish subject, and continue on your way, finishing up your dive shortly. As you ascend with your dive group to the boat, you notice a burning sensation in your left hand. You shake it out a bit and stretch your fingers back and forth. The pain gets worse, and by the time you flop back onto the boat, the stinging radiates through your entire palm. This is just the beginning of a week-long ordeal of pain, irritation, and suffering.

On your dive you unknowingly made a grave error; touching fire coral (Millepora), incurring its venomous wrath straight into your soft, unprotected hand.

The term “fire coral” is actually misleading. The fifty or so species of Millepora, found across the Indo-Pacific (except for Hawai`i) and the tropical Atlantic and Caribbean, are not corals at all, and are actually quite distantly related to them. While both “fire coral” and standard stony corals are colonial animals in the phylum Cnidaria (a group that also contains jellies and sea anemones), they are in entirely different taxonomic classes. True stony corals are what we call “anthozoans” (a term meaning ‘flower animals’), and are close relatives of things like anemones and sea pens. “Fire coral”, in contrast, is a “hydrozoan”, and is closely related to things like freshwater hydras, colonial siphonophores like the Portuguese Man ‘o War, and the by-the-wind sailorMillepora is a member of a group of cnidarians that includes creatures that look and act a lot like “true” jellies, class Scyphozoa (“jellyfish” or “jelly” is a term that is applied to many groups of free-swimming, bell-shaped cnidarians, whatever their evolutionary lineage)….yet, to the untrained eye, looks indistinguishable from any of the corals that make up the reef.

However, looking closer at these vast colonies of hydrozoans helps illustrate just how different they are.

Both Millepora and true stony corals are colonial organisms, meaning that their big, branching structures are made up of many multitudes of single organisms (called “polyps”), articulated and fused together like the apartments making up a high-rise skyscraper. Coral polyps are like very, very tiny sea anemones in overall shape; little mounds with soft tentacles surrounding a mouth hole. They are, however, encased in a hard aragonite skeleton (a “corallite”), with the feeding tentacles (which are covered in “cnidocytes”, the explosive, venomous harpoon-primed stinging cells found in all cnidarian groups) alternating between being exposed to the water, or retracted within the skeleton. Corals feed on planktonic bits that stray into their outstretched tentacles, and most shallow water species are also supplemented by symbiotic unicellular algae (“zooxanthellae”) that live inside of the polyps and provide food energy via their own photosynthesis.
Millepora also harbor zooxanthellae and derive energy from them, but the structural units by which they generate their giant colonies are markedly different. Instead of distinct polyps sheathed in a rigid corallite, the surface of a fire coral colony looks like close-up of Edward James Olmos’s face. It is a plain of diminutive pores and pockmarks (“millepora” means “thousand pores”), each housing a polyp. However, in fire coral, the polyps fall into a number of different types. The two most common types are gastrozoids and dactylozoids. Gastrozoids are the feeding polyps, and in this way, are similar to what you’d see in a coral polyp. Most of the time, gastrozoids are retracted deep below the surface of the colonial skeleton, where they are connected to one another by a network of canals, so nutrients can be distributed between individuals. The dactylozoids are strange by comparison; mouthless, their job is to catch prey and feed it to the gastrozoids. They have long, thin, wispy, transparent tentacles that stick straight out, making the colony look like it stole its hair style directly from Bernie Sanders. These dactylozoids and their tentacles are the ones armed with the stinging cells that dole out the pain to microscopic plankton and misplaced human limbs alike.

Feel the Bern….literally

Contact with the dactylozoid tentacles causes the cnidocytes to do their one and only job; shoot out a barbed harpoon at blistering, impossible speeds directly into whatever triggered it. How impossible? The discharge of the stinging cells takes roughly 700 nanoseconds, which is an acceleration so stupidly huge that the harpoon is subjected to more than five million times the force of gravity….some 5,410,000 g. This mechanism produces, far and away, the highest acceleration of any animal on the planet. To put that value in perspective, for a human to experience that g-force on a standard merry-go-round with a 15 meter radius, you would have to be spinning around at more than 182,000,000 miles per hour. This is so fast that you would travel the equivalent of the Earth’s circumference in less than half a second. Not only would the force nearly instantly liquefy you, even down to the collagen that holds your tissues together…but the air friction generated from such speeds would incinerate whatever remained.

Basically, what I’m trying to say is that the spring-loaded harpoon of a discharging cnidocyst is fast.

Once that harpoon tip hits its target, venom is injected into the puncture site through the hollow tubule that runs from inside of the harpoon, down the thread, and into the capsule of the cnidocyte. Cnidarian stings vary widely in how seriously they impact human physiology. Many sea anemones have mildly irritating stings, while some cubozoans (box jellies), like the sea wasp (Chironex fleckeri) has sting that has been implicated in human fatalities. Fire coral falls somewhere in the middle. For Millepora, it takes usually at least a few minutes for the first symptoms to show up after a sting. Hot, burning pain is the predominant shit you would have to deal with, and it is the first to rear its head. Red, irritated welts and blisters raise on the skin in the impacted area, and in some cases, in the hours following the sting, the sufferer may experience nausea so strongly they end up barfing a bit. The pain eventually gives way to intense itching after a while, and the red rash can remain for a week or more. The sting’s effects are certainly unpleasant, a little like mosquito bites on top of poison ivy on top of a gnarly sunburn, but they are, at least, not life-threatening. Barring a rare allergic reaction, fire coral ain’t going to kill you. Really, a much more likely scenario to be cause for concern is if someone came in contact with Millepora by getting scratched or cut by it. Cuts sustained from coral or Millepora are exposed to mucus from the coral, full of irritating proteins, as well as tiny chunks of calcified skeleton. This, together with the cut being submerged in a marine soup of microorganisms, means that coral scrapes are particularly slow to heal and infection-prone. If the skin is broken, essentially, the most dangerous element of a fire coral encounter potentially has nothing to do with the venomous colonial critter itself.

So, it’s just good policy to not touch anything that looks like it could be coral. Touching pisses the coral off and/or kills it, and touching coral can end up indirectly hurting you, and THAT pisses YOU off. There’s not a lot of winning here.
Don’t touch urchins, either. Even if they look like they are made entirely out of gelatin trumpets. Actually, especially if they look like that.

Venom has evolved in a hell of a lot more critters than snakes, scorpions, and spiders. Some of them are brightly-colored buzzing nightmares, some are underestimated miniature vampires, and some don’t even look like animals at all. Takeaway from all of this? If you are out in our big world and see a new beastie thing, and you desperately want to pet the thing, remember that maybe you really shouldn’t pet the thing.

Image credits: Intro flower urchin, tick hypostome, tick before and after feeding, Toxopneustes, flower urchin pedicellaria, fire coral scene (Derek Keats), fire coral tentacles (Eric Burgers)

© Jacob Buehler and “Shit You Didn’t Know About Biology”, 2012-2015. 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.

Venomous and Underrated: Hymenopteran Horrors

I have a penchant for particularly noxious lifeforms, the ones that have evolved nasty chemical tools for either fending off bigger, badder, and hungrier things, or bringing down breakfast. Anyone who has read the breadth of this blog should now be aware of my adoration of the biology of such fundamentally antagonistic critters, the mark of which has been left behind in the number of entries devoted to the lesser-appreciated toxic flora and fauna of the world. Deadly, toxic mushrooms. Boxfish, with their poisonous mucus. The terrifying, seafood-driven, hallucinatory rollercoaster ride of ichthyoalleinotoxism. Pungent vinegaroons and acrid harvestmen. Venomous caterpillars that make you bruise like a peach….to death. Birds that silently embed concentrated toxins in their fucking feathers.The “Do Not Touch” exhibit in the Museum of Life has made a strong showing within the overall theme of Shit You Didn’t Know About Biology. I mean, Christ, my very first post on here was about an insatiable aphid-slaughtering deathdozer that bleeds poison foam.

Most of the unsavory representatives above are of a particular variety of being, well, molecularly disagreeable. Up until now, I’ve chiefly yammered on about “poisonous” and “toxic” organisms (with the exception of that intimidatingly venomous caterpillar), things that secrete or store harmful compounds in or on their bodies, such that the aggressor the poisons are intended for must passively absorb the toxins through digestion, or through the skin and mucus membranes (considering my research on boxfish, this bias towards this type of defensive strategy shouldn’t be all that surprising). Nature also hosts plenty of “venomous” organisms, which entails a much more direct, Type A approach to chemical warfare, wherein the poison punch is forcefully injected via a (generally quite pokey) delivery system that has evolved specifically to fuck up your day.

There are plenty of well-known venomous superstars, and it is especially the venomous snakes and spiders that garner the lion’s share of the limelight. A fair number of people are familiar with the superlatively deadly representatives of these groups, from sea snakes, cobras, and taipans, to Brazilian wandering spiders and Sydney funnel-webs, which regularly make appearances on just about every heavy-handed, suspense-saturated, kitschy “TOP TEN DEADLIEST” daytime special to run on Discovery, Animal Planet, or Nat Geo for the last decade or so.

But the brush painted by the evolutionary strategy of venom is broad, and the technique has cropped up in a surprising number of very distantly related lineages. This two-part series of posts will be devoted to the unsung venomous animals, which neither slither through the grass or canopy (nor thwart the professional efforts of John Goodman), and within their ranks, not even necessarily the most dramatically dangerous or traditionally telegenic and charismatic representatives. These other animals, however, have evolved injectable weaponry that is truly remarkable on its own merits, by a diversity of metrics, despite not achieving comparably towering levels of renown. Much attention has been bestowed upon the black mambas and black widows, the Clooneys and Jolies of venom notoriety. It’s appropriate to give the Goldblums and Leguizamos their day in the sun for once.

When it comes to animal diversity, insects are an undisputed juggernaut. Their taxonomic class, Insecta, potentially holds as many as ten million species…but it’s a quantity we can never quite pin down, since we continue to discover truckloads of never-before-seen creepy-crawlies just about every goddamn time we peak into the dark, dank undergrowth of equatorial rainforests, so our admitted level of ignorance tends to be a moving, inflating entity.

But there is one insect group within this overwhelming ocean of species, more than any other, that has forced humans to have an intimate familiarity with the throbbing cruelty of venom. This group numbers 150,000 species strong or more, and is found on essentially every major landmass on the planet. Entomologists know them as the Order Hymenoptera. To most everyone else, they are the bees, wasps, hornets, and ants. Hymenopterans, as a group, are responsible for more annual human deaths then just about any other venomous clade. In the U.S. alone, about 40 to 50 people die from just bee stings every year. Part of this is explained the by the allergenic properties of hymenopteran venom, and how severe allergies to stings aren’t all that uncommon. The other reason is tied to contact; the angry, swarming, stinging bastards are everywhere. Large numbers of humans have had heated interactions with hymenopterans at some point in their lives. Whether it was stumbling over a yellowjacket nest, or getting a little too close to that arboreal, roadside beehive, the transgression invites a cloud of livid, buzzing pain-missiles upon their panicked, flailing selves. The burning of potentially dozens of stinger-fulls of venom is an experience billions of humans learn to carefully avoid.

Personally, I regard hymenopterans with a severe level of caution; not because of an allergy to their stings, but because of my near-phobic degree of fear in their presence (a feeling of unrelenting trepidation that also has driven a fascination and respect for their incredible biology). But even I had to learn their venomous nature from early, first-hand encounters. My earliest interaction with a bee occurred when I was three years old, playing in my grandmother’s landscaped front yard. I was convinced that the silly, fuzzy, striped bug sniffing all the flowers would feel nice and soft in my pudgy toddler hands.

It did not feel nice. It did not feel nice at all.
I haven’t felt comfortable around bees since. First impressions fucking matter.

Beyond your common honeybee or picnic-crashing ant, there are a number of famed members of the hymenoptera long recognized for their especially brutal stings. These Celebrities of the Sting are worth mentioning briefly, if for nothing else but to get their prestigiously painful asses out of the way. For one, the fire ant (Solenopsis invicta), native to tropical South America, has a well-earned reputation for aggressively defending its colony by vigorously stabbing trespassers with a decidedly painful venom, resulting in the eruption of searing blisters and, potentially, anaphylactic shock. Fire ants have commanded worldwide attention due to their status as a hard-to-eradicate nuisance and invasive species in the Southern U.S., parts of East Asia, the Caribbean, and Australia (a place that certainly doesn’t need more cantankerous beasties). Then there’s the fire ant’s notorious cousin, the bullet ant (Paraponera clavata), also native to the Neotropics. This gargantuan black ant, burly enough to hug a penny, is thankfully not established anywhere outside of the deepest recesses of Central and South American rainforests, because it harbors a sting widely regarded as the most painful on the planet. That name? Bullet ant? It has nothing to do with its 400 m dash time or its NRA membership. No, it’s called the “bullet ant” because its sting makes you feel as though you’ve been fucking shot with a handgun. You then endure the wonderful experience of unabating, unfathomable quantities of madness-inducing agony, making you sweat and tremble uncontrollably for what seems like an eternity of supernaturally savage punishment.

If you’ve ever sat through the 91-minute runtime of this cinematic abortion, you’ll know the feeling

But lastly, buzzing ominously above the zenith of hymenopteran sting infamy is the Asian giant hornet (Vespa mandarinia), very recently made familiar to the world outside of its native East Asia thanks to nature programming and the collective gasping and shivering of a generally entomophobic Internet. I’m not entirely certain why, seeing as how it’s fundamentally no different than a normal hornet….except for how it’s bigger than a canary, has a quarter-inch long stinger, and is consequently the most distilled, pure incarnation of “hell fucking no” to ever exist. And how they spend their time nonchalantly pinning down things more than twice their size and chewing off their faces. And how they violently dismember European honeybees faster than Spartans mowing through Persians in a Zack Snyder film. And how they do things like this to the most fearsome, heartless insect predators around:

Yes, it’s eating a praying mantis. And yes, you just peed a little.

Oh, and then there’s that whole thing about how when it plunges that jumbo-sized stinger, which is as thick as a motherfucking thumb tack, into your delicate, mortal flesh, it feels like “a hot nail” being driven through you. It’s less “bee sting” and more “getting stabbed with a soldering iron.” The volume of venom unloaded by these stings is likely three times higher than what more modestly-sized hornets dole out, and because of this, a comparably low number of stings can be life-threatening, even for the non-allergic. Seriously, particularly bad attacks of Asian giant hornets end up killing people by the dozen on the reg, immense volumes of venom turning their organ systems to jelly.

So, yes, perhaps no hymenopteran is as viscerally manhood-wilting as Vespa mandarinia, but in actuality, the world’s largest hornet only holds a title in regards to its girth. Part of the reason so many people are killed and injured (as many as 1,600 in what probably seemed like an astoundingly apocalypse-y year for northern China), is because this hornet is common in low elevation forested habitat near some of the densest aggregations of humans on the planet; Japan and coastal China. This means that humans and giant hornets are relatively likely to run into one another. Despite its overall lethality and destructiveness to human happiness, this yellow-and-black, colon-purging nightmare isn’t especially venomous as far as hymenopterans go.

To find the possessor of the most potently pernicious posterior prick among wasps, one must go to the Philippines and hunt down the Asian giant hornet’s relative, Vespa luctuosa. This hornet, endemic to the Philippine archipelago alone, doesn’t have a common name, which opens the door to me coming up with one on my own for the sake of ease. The Philippine fucker-upper. The Manila killa’. The Pinatubo painmaster. But perhaps simply “Philippine hornet” will work better here. In life, the Philippine hornet doesn’t really stand out from the hornet pack. It lives a standard, tropical hornet life, crafting spherical papier mache nests that hang from rainforest trees like the world’s least enjoyable piñata. It has a notably darker coloration than many hornets, with only a few thin, rogue bands of deep yellow appearing at the back of the abdomen near the stinger.

Yeah, dark…like its soul
Photo: Lary Reeves

Additionally, the Philippine hornet is something of a hermit, generally not associating well with human encroachment and keeping to itself in undeveloped regions of the hot, humid rainforests it calls home. This is definitely for the best, since this drab hornet has a venom whose potency ranks highest among wasps, and is one of the most potent of any insect, period.

Toxicity of substances is often given as an LD50 value (or a “median lethal dose”), which represents the dosage of venom needed to, statistically, kill 50% of a given population of a test animal. Often, this dosage is listed as milligrams of venom per kilograms of mass of the poor, envenomated subject sacrificed on the lab bench (often a mouse). The value also tends to vary with how the venom is injected (below the skin vs right into vein, for example). The lower the LD50, the higher the toxicity, since a lower concentration is needed to achieve a 50% kill rate. The Philippine wasp’s venom has an LD50 of about 1.6 mg/kg in mice, and in contrast, the imposing Asian giant hornet has venom achieving a value of over 4 mg/kg. Compared to the most venomous snakes, like Pseudonaja and taipans, this is 10 to 100 times less potent. Philippine hornet venom is more on par with that of the king cobra (Ophiophagus hannah) in drop-for-drop deadliness. If the idea of hornets flying around with honest-to-Jiminy-cocksucking-Christ cobra venom in their stingers makes you sweat like Ned Flanders in a strip club, consider that envenomation volume makes a huge difference. The king cobra can pump out as much as seven milliliters (a quarter of a whiskey shot glass) of venom in a single bite, but the sting from a single Philippine hornet is going to dispense a tiny fraction of that amount. However, this venom is potent enough that each hornet possesses enough venom to statistically kill a dozen mice; meaning, that if you took their entire load of venom, and distributed it among twenty-five mice, statistically, half of them would die. That’s not “cobra serious”, considering that hornets don’t blow their whole venom load in a single sting, but it’s conceivable to see how an uncoordinated trailblazing effort, a clumsy collision with a colony, and dozens of stings later might put your ass in some hot water, sting allergies not even considered.

This one has a pin sticking through it, and is a dried-out, four decade-old corpse, which makes it slightly less dangerous than normal.

“Well,” you say, sitting in the air-conditioned comfort of your home in the Tempe ‘burbs, “it’s a good thing I don’t live in the Philippines.” Sure, you think, living in Arizona, Earth’s scrotum-melting broiling pan, has its own throng of difficult residents that goes along with it. Rattlesnakes. Scorpions. Gila monsters. Homophobes. Racists. Racists. Still more racists. Racists everywhere. Did I mention racists? But you can adjust to all of that in time, and through simple things like developing a drinking habit and never going outside during the daytime. It’s not like the most venomous insect on the planet could potentially skitter up to my sun-scorched doorstep or something.

Oh yeah, except for how that’s totally a thing that can happen.

North, Central, and South America are home to a genus of ants (Pogonomyrmex) collectively known as “harvester ants.” They are a diverse group, and about seventy species of Pogonomyrmex run frenetically across the hot, arid regions of the New World. They, much like the aging Tucson hippies they share their habitat with, are seed-eating specialists, and workers forage for small seeds to take back to their subterranean nests. They are industrious little creatures, and as a result, there tends not to be much in the way of vegetation growing near the entrances to their colonies, the landscaping dominated by sand and gravel. Outwardly, they are unremarkable as far as ants go. Small. Bent antennae. Six legs. Pinched waists. Bullet-shaped butt and a round head. Chastises Grasshopper for being an ever-idle moocher. No surprises here.

That is the most anty-looking ant I’ve ever seen.

Look a little closer though, at the far right, at the teardrop tip of its shiny, caramel abdomen. See that sliver poking out through the white bristles there? That is a stinger, not unlike that of the Philippine hornet or any other typical hymenopteran.

It’s important to remember that while ants are a big group, with a towering number of species in their ranks (somewhere between 12,000 and 20,000+, it’s hard to tell), they all reside within a single taxonomic family (Formicidae). A family, by the way, nestled among a whole suite of families of “wasps” in a superfamily cluster termed the “vespoids” (which are all your typical, yellowjackety, waspy type creatures). Ants are just a group of specialized vespoid wasps that have taken to the ground and lost their wings. Well, most of them. Many species reserve the retention of wings for a select few social castes. Ants are newcomers among insects, diverging from their wasp brethren only within the last 120 million years or so, and it’s easiest to think of the family as simply wasps with a few modifications. Certain features of their biology and anatomy betray their ancestry, and more so in more primitive groups of ants. For example, a powerful, painful sting tends to associate with groups of ants that were earlier offshoots within the family; the notorious bullet ant, with the most brutal sting of all, is a member of a comparatively ancient group of ants known as poneromorphs. In the “canopy” of the ant family tree reside lineages that have lost stings altogether, converting their venomous butt darts into a contraption that sprays formic acid.

Pogonomyrmex is one of those ants that holds onto the weaponry of its aerial forebears with as much tradition-rescuing, white knuckled zeal as an 80 year-old defiantly maintaining that the restaurant down the street serves “Oriental” food. And boy, have they found a way to make it their evolutionary nostalgia count. Harvester ants, as a group, have the most venomous stings of any insect, with the highest honor falling upon Pogonomyrmex maricopa, a nondescript ant found chiefly in the Sonoran and Chihuahuan Desert regions of Arizona, but actually ranges through the adjacent desert lands of Utah, Nevada, southern California, and New Mexico. This species has the most potent venom of any insect, with an LD50 recorded at 0.12 mg/kg. For context, consider that this is more than ten times more potent than the already hyper-venomous Philippine hornet’s sting, and has a similar punch to the venom of the Russell’s viper (Daboia russelii), a snake infamous for killing thousands of people across South Asia every year. From the human perspective, these guys are itty bitty, and each sting delivers a minuscule dosage of venom. But it does the job, and the result is several hours of hot, blinding pain, effectively making Pogonomyrmex maricopa‘s sting the most aggressively repellent thing to hit the Grand Canyon State since Joe Arpaio flew on in, powered solely by jowl oscillations and hot air.

But why have such a dickishly venomous sting? Not all ants, apparently, have the need to be so outlandishly nasty, so why the harvester ants? The answer lies in how venoms evolved in hymenopterans. Hymenopteran stingers evolved from the egg-laying tubes (called an “ovipositor”) of females to dispense a painful, toxic chemical “persuader” to unwise attackers of a colony or nest. The entire point of these venoms is to induce enough torment that a nest raider loses all motivation to complete Operation Tear Open the Humming Food Ball, and instead limps off to engage in Mission Lick Wounds and Whimper Self to Sleep. It also helps if the experience is agonizing enough to keep the intruder from returning without a careful evaluation of its life choices. The sting of a hornet or an ant is there for defending the hive or nest, often from something big and hungry. So what the hell are the harvester ants defending themselves against that would necessitate the evolution of such potency?

Enter the Texas horned lizard (Phrynosoma cornutum), a thorny, squat, tank-like lizard that makes the arid lands of the interior Southwest its home. Biologists know it as a member of the diverse group of “North American spiny lizards” that are found all over the continent, but you may know it as that one lizard that can turn its blinkers into a blood cannon or as the star of the “Laughing Lizard” Internet meme. The Texas horned lizard may look a little comical; it’s hard to take seriously an animal that looks like a combination of a frog and a cactus that was run over by truck. But when it comes to eatin’, this lizard doesn’t fuck around. The Texas horned lizard, fitting right in with the Lone Star State crowd, has a heightened culinary appreciation for spicy food, as more than two-thirds of its diet consists purely of Pogonomyrmex ants. This is an animal that trains its blank, saurian gaze on a pulsating, angry, red mound of toxic fury and says “yeah, I can eat that.” The horned lizards, as a group, are harvester ant-eating specialists. I really mean “harvester ant specialists” too. They target these picante pricklers only, and will forgo eating things like invasive fire ants, which is actually the less venomous, “pico de gallo” alternative, and rigidly stick to their native, “ghost pepper” option. This is actually a conservation problem for horned lizards, because invasive, omnivorous fire ants are currently killing and eating harvester ants at a breakneck pace…eliminating the bulk of the horned lizard’s diet, leading to falling lizard populations.

There’s evidence to suggest that the super-charged stings of harvester ants are the result of such aggressive, narrowly focused predation, resulting in a coevolutionary feedback loop, where the ants evolve even stronger stings, and in response, the horned lizards come back them with the evolution of even better venom tolerance. It turns out that horned lizards are really goddamn good at absorbing Pogonomyrmex stings. How good? Better than mice, that’s for sure; the LD50 for Pogonomyrmex maricopa venom in horned lizards is 162 mg/kg. This means that it takes more than 1,300 times more venom to, statistically, kill as many horned lizards as it does mice of the same size. The difference in venom tolerance between horned lizards and close relatives is huge as well, just in case you thought it a reptile-vs-mammal thing was to blame; the LD50 for the venom in the fence lizard Sceloporus is a sixth of what it is in Phrynosoma cornutum. The resistance appears to be something running through the lizards’ inner piping, because when you inject mice with horned lizard blood plasma, the some of that resistance to the ant venom is transferred over. Horned lizard physiology casually shrugs off harvester ant venom proteins, handily detoxifying the deadly cocktail like it was nothing more than baby aspirin.

Horned lizards also avoid getting too much venom into their bodies in the first place by incapacitating the ants. However, this happens much later in the “eating chronology” than most people would prefer for consuming an army of six-legged hellfire. Horned lizards rapidly gobble down the ants whole, attempting to eat dozens in a single sitting. When the wee bastards enter the digestive system, they are very alive and more than a little piqued. Before they can arch their abdomen back and unleash a bout of heartburn that reptile won’t soon forget, they are enveloped in thick, heavy mucus, and frozen in place as they are shuttled down into the stomach. Horned lizards have evolved a series of unique, finger-like projections and folds that line the inside of their upper digestive tract and produce copious amounts of snot that binds and immobilizes the ants as soon as they get swallowed. Horned lizard gullets are like a water slide, but pitch black and full of molasses. They can shovel ants in their mouth freely, never worrying about hymenopteran havoc being wrought on their vulnerable stomachs. I guess you can say all that protective phlegm acts as an….ant-acid.

See? He thinks it’s funny.

The combination of this, and how they brush off harvester ant venom like Bukowski brushing off half a handle of bourbon, allows horned lizards to fill up on the most painful meal in the desert in relative peace, unaware of the silent, coevolutionary war taking place between them and their food for hundreds of millennia.

You may have noticed that the correlation between venom potency and danger to humans isn’t very strong when it comes to these insects and their stings; Asian giant hornets kill heaps of people annually, but have relatively mild venom, and the chemically formidable stings of Philippine hornets and harvester ants may hurt like shit, but haven’t really been associated with human fatalities. Are there any ants, then, that somehow manage to summon EMS sirens wherever they clash with humans, despite their relatively dinky potency?

The answer is yes, and they can be found in Australia. Because of course they fucking can.

Australia is no stranger to periodically murderous wildlife, especially of the venomous variety. Hell, half the examples of highly-venomous snakes and spiders I’ve mentioned in this blog post hail from Oz. The entire goddamn island continent is awash in a diversity of venomous animals, a disturbingly high proportion of which are armed with venom vicious enough to drop your carcass to the hot, antipodean dust for one of those “forever” kind of naps. I’m half convinced that koalas and wombats aren’t real animals, and were artificially contrived by the Australian government to distract tourists from the ever-present, shin-deep layer of funnel-web spiders blanketing the country. I suspect Australia is so damn dry because rain is simply too afraid to fall there. What I’m trying to say is that Australia is what’s on the other side of the inter-dimensional, fog-bound portal in The Mist.

So, it is no real surprise that something as cartoonishly intimidating as the bull ant (Myrmecia) feels comfortable enough to make its home there.

That right there is about two centimeters of NOPE

They are an old, primordial group of ants, with essentially no close living relatives. Their primitiveness is readily observable in their social structure and the loose delineations between castes. They aren’t nearly as cohesively cooperative with one another as more recent ant groups. There’s more of a libertine, laissez-faire approach to things, with more infighting, and less collectivist, colony-driven, group motivations. The division of labor isn’t as well-pronounced, nor is the presence of physical differences between reproductive and worker castes. For example, they are among the few lineages of ants that, in addition to a queen, possess “gamergates” in their colonies; worker females that retain the ability to mate with a male and reproduce. The fossil record shows that back in the Cretaceous, bull ants had a large geographic range, extending onto just about every continent. But, in the modern age, the remaining hundred species of ant in the genus Myrmecia are all found only upon the continent of Australia (save for a single species holding out on New Caledonia, a nearby group of islands between Fiji and the Solomon Islands). Apparently, this is an ant that liked to live dangerously, and after the dinosaurs went worm counting, the only place left that was treacherous enough to set up shop and keep the adrenaline pumping was fucking Australia.

An encounter with Myrmecia in the flesh truly does engender the feeling that they hail directly from a bygone prehistoric age, full of harsh challenges that the lily-livered ants of today could never even imagine. For one, the worker ants are gigantic by ant standards. While not the largest ants in the world (surpassed by the famous, previously mentioned bullet ant, and the tocandira), many bull ant species can have a worker caste that can nearly reach an inch and a half in length, which is longer than the distance between the tip and first knuckle of your thumb….not that you’d ever want to get your hand close enough to measure. Secondly, you may have noticed that bull ants have a set of weaponry that most ants do not; serrated, pinching jaws, longer than the head, extending forward like a pair of cruel bread knives. These mandibles aren’t just for show, and can snap together with blinding speed and savage force, puncturing and clenching whatever is in their path. Bull ants have pneumatic meat hooks where their face should be.

Aww, look! She’s smiling!

Evolution has molded these ant mouthparts (which are normally quite modest in other genera of ants) into Satan’s pinking shears, and they have a key job in the life of the bull ant. And while I know they are intimidating to look at, no, it isn’t killing and dismembering buffalo. The adult ants are omnivores, eating everything from nectar, to fruit, to seeds, to the liquefied remains of small insects…but their maggot-like young are fully carnivorous, and require a fresh, dripping kill to grow up big and strong. So, adult bull ants lead an active and athletic foraging lifestyle, usually solo, using their big eyes and keen eyesight to track down prey from surprisingly long distances away. Bull ant workers then use those brutal chompers to pin down anything they can in a vice grip; grasshoppers, beetles, more pusillanimous species of ants, and, in a bizarre table turn of food web convention, spiders. Yes, spiders. Charlotte’s Web would have ended slightly differently were it set in Australia.

“Wilbur! Wilbur, help! Wil-ggaaaaghhh!!!”

But the killing blow to their wriggling, soon-to-be-baby-food quarry comes from Myrmecia‘s venomous sting. And it is their sting, not their bite, that makes bull ants dangerous to humans. In fact, one small, common species, Myrmecia pilosula, the “jack jumper”, so named for its habit of lunging and bouncing when disturbed (a similar behavior is seen in Myrmecia gulosa, the “hoppy joe”), is responsible for several human deaths, and is the cause of many hospitalizations in Eastern Australia and Tasmania. Bull ants like the jack jumper and hoppy joe may have disarmingly ridiculous, very Australian nicknames that sound more like a brand of small firecrackers and a rabbit-themed coffee shop, but it is clear that their venom is nothing to giggle at.

The jack jumper is an ant that shies away from the dense urban habitats of Australian population centers like Melbourne, Brisbane, and Sydney, but is common in open, more undeveloped areas all over the country. They easily stake their claim and establish colonies on the borders of suburbia and rural regions, and as a result, humans regularly spot them and are stung by them when engaging in outdoor activities. This is a problem, because the venom from these ants is apt to kill people dead.

The deadly nature of Myrmecia venom isn’t related to a blanket potency. Realistically, bull ant stings generally aren’t particularly venomous, on their own, compared to other hymenopterans. Much of the time, a jack jumper sting results in a painful boil and local swelling that persists for a few days, similar to a fire ant sting. Not much is known about the venom’s calculated potency in whole animals, but pilosulin 1, a protein in jack jumper venom, is known to have an LD50 concentration value for a certain type of white blood cell that is four times lower than melittin (a major component of bee venom).

However, it isn’t the straight toxicity of compounds like pilosulin 1 that make a jack jumper sting potentially deadly, it’s the uniquely allergenic properties of the venom. Jack jumper stings are dangerous because a shitload of people have severe allergic reactions to them. In Tasmania, where jack jumpers are highly abundant and cause the majority of severe stings (and resulting deaths), the prevalence of severe allergies to stings sits at around 3%, twice as high for honeybees (a hymenopteran famous for getting the immune systems of countless humans to self-destruct with deadly consequences). Unsurprisingly, the same study linked to above has shown that as many as one in fifty Australians have reported anaphylactic reactions to stings from jack jumpers or other Myrmecia ants. In Australia, most anaphylaxia cases from insect stings are attributed to jack jumper ants, not from bees, making Australia possibly the only place in the world where bees are beaten at their own immunogenic game.

Not only are jack jumper stings more likely than bees to send you to the hospital, a pale, swollen, barely breathing mess a step away from death…but they are more likely to do it more than once. If you’ve had a major allergic reaction to a jack jumper sting, and you get stung once again, you might not want to wait until the symptoms get bad before you get the fuck to the hospital. There’s a 70% chance that this repeat sting will initiate a catastrophic allergic reaction just like the last time. For honeybees? It’s about 50-50. About half as likely than that for wasps. Myrmecia stings do what honeybee stings do, but they do them better. Better than an animal that, generally speaking, is really damn likely to kill you…more likely to kill you than pretty much any other.

This potent allergenic effect probably isn’t mitigated at all by another protein in jack jumper venom; pilosulin 5. Pilosulin 5 causes mammalian mast cells to dump buckets of histamine all over the place…you know, the same crap that basically causes all symptoms of every allergy ever.

The jack jumper issue has been so bad for so long in Tasmania, that around a decade ago, an immunotherapy program was set up to desensitize the particularly allergic to the venom. It has been largely successful, and it, along with enhanced public awareness of the dangers of the venom, has contributed to a sharp decline in jack jumper sting deaths in the island state. Until the start of the new millennium, someone perished at the butt-end of a jack jumper once every few years, but there hasn’t been a recorded death that can be attributed to the ant for more than a decade now.

Hymenopterans and their venom manage to reign supreme in the insect world, but underappreciated venomous critters abound in many lineages and environments. To see some, you may have to plunge into tropical, coral reef waters, and for others, just go for an off-trail jaunt on your next backwoods hike…. (continued)

Image credits: Intro image, giant Asian hornet eating mantis, pinned Vespa luctuosaharvester ant, Myrmecia and ruler, jack jumper close-up, Myrmecia catching spider

© Jacob Buehler and “Shit You Didn’t Know About Biology”, 2012-2015. 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.

High Tide: Hallucinogenic Fish

I love to eat fish.

Fish is by-and-large my favorite dietary source of protein, and living in Hawai`i means that I get to indulge in this adoration for finned flesh perhaps more often than I should. In the islands, there are plentiful, fresh fish of a staggering diversity sold and consumed everywhere you turn; firm and buttery a`u (Pacific blue marlin, Makaira nigricans), rich opah (Lampris regius), ubiquitous mahimahi (Coryphaena hippurus) and `ahi (Thunnus), lean and flaky ono (Acanthocybium solandri), and delicate `opakapaka (Pristipomoides filamentosus) are just a few. There’s also uhu, ulua, aku, uku, mamo, manini, akule, palani, awa, ama`ama, u`u, opelu, nenue, kamanu, omaka, hapu`u, `ula`ula koa`e, moi, ukikiki, kahala, kala, umaumalei, wahanui, and moano too. Introduced species? Hawai`i has roi, ta`ape, and to`au. Great, glistening troughs of poke line the deli section of just about every grocery outlet on my island (Safeway, local chains….liquor stores), and upon seeing them, I inevitably have to command my legs to carry me away from a fate involving a plastic container of heaven, chopsticks, and a wallet seven dollars lighter.

There are a number of reasons why avoiding the reduced price special on the limu `ahi at the Liliha Foodland may be a wise decision for just about anyone (temporarily salvaged funds unconsidered). As with any food, there are inherent risks, and fish have a unique repertoire of ways they can make a regretful meal. Perhaps the most readily publicized is the health risk posed by the bioaccumulation of methylmercury in the tissues of a number of fish species typically taken as food by humans. One bite of a particularly metal-saturated swordfish steak isn’t going to promptly send you to tea with Alice and a rabbit, and the accumulation of the poison in humans takes time (and LOTS of contaminated fish consumption). But, there are more acute ways a fish filet can bite back. For one, the fish may be highly endogenously toxic, meaning that the fish embeds poisonous compounds into its own essence, it’s own bodily tissues. Pufferfish are well-known for this approach, and many species have organs loaded with tetrodotoxin (TTX), a naturally-occurring, chemical Angel of Death so potent that it makes cyanide look like fucking ibuprofen. Preparing pufferfish for the passage between human lips takes all the insane, brow-beading, calculated finesse of disarming a bomb, but despite the supreme level of care of highly-trained culinary experts, every so often, people drop dead after ingesting the fish. Really damn dead. There are also the ever-present risks of conventional, bacterial food poisoning and infection with parasites like tapeworms and roundworms, both of which are more likely to occur in the less-than-cooked form of fish (my personal favorite state of fish).

Yes, you potentially need to watch what you eat when it comes to fish, whether you risk the slow march of mercury toxicity or a weekend hovering over the world’s unhappiest toilet. These risks are generally understood and expected.

What isn’t expected from your seafood? That you might get high off of it.

The phenomenon is called “ichthyoallyeinotoxism” or “hallucinogenic fish inebriation”; both are just jargony ways of saying that, somehow, the catch of the day has you hearing colors. Occurrences are uncommon, but there are plenty of baffling records, ancient and modern, of humans coming away from their sea-borne suppers with more to worry about than a bit of lemon wedge-fueled acid reflux. Like how to convince the grumpy, five-headed emu in the corner of the room that you don’t have any millipedes hiding under your fingernails.

“Alright, everybody, time to get weird!”

The actual inebriation scenarios vary greatly, between species of fish, and between intoxication events. Onset of symptoms can occur within minutes, or hours, and can last from a couple hours to more than a day. Sometimes there is gastrointestinal upset. Sometimes not. Often times, the sufferer endures a loss of coordination and balance, along with muscle weakness and a burning of the throat, but none of this is guaranteed either. Ichthyoallyeinotoxism, as a peculiar clinical feature, is more or less defined by the presence of vivid hallucinations and/or nightmares, and a capacity for intoxication in even cooked fish (suggesting that whatever compounds are responsible are also very heat stable). Typically, symptoms outside of the psychoactive effects tend to be pretty mild, and temporary, contrasting with the peripheral nervous system assault characterized by other forms of fish flesh poisoning (“ichthyosarcotoxism”).

Ichthyoallyeinotoxism has been reported in a diverse array of marine fish, but it has most regularly been associated with one species in particular; the Salema porgy (Sarpa salpa). This species of sea bream is common along the West and South coasts of Africa, as well as throughout the Mediterranean Sea. The Salema porgy is a rather conventionally-molded, petal-shaped fish that grows to about the size of a football, identifiable by glittery golden stripes that run the length of its body. The fish’s occasional ability to get humans hippy flipped has been recognized for ages, and Salema porgy (also referred to as “saupe”) was routinely eaten for recreational purposes across the Roman Empire. If these long-gone citizens were around today, they would likely regard Long John Silver’s as a glorious drug den franchise.

Scene from Seneca’s 36 AD theatrical tragedy, Reef Madness, or alternatively, De Otio Malus, “On Harmful Leisure”

For centuries, the fish (like many other species of ichthyoallyeinotoxic, or “hallucinogenic”, fish) has been called “dream fish” or “dream bream” for its psychedelic effects. The reputation continues until this day, however, since poisoning happens only on occasion, the Salema porgy is far more commonly consumed in the typical way fish are: as a food, not as a drug.

But, every so often, this backfires in spectacular fashion. In 2006, two case reports were published concerning recent ichthyoallyeinotoxism events caused by Sarpa salpa ingestion, both occurring along the French Riviera. In 1994, one of the unfortunate diners (a 40-year old executive) made the poor decision to partake in some baked Salema porgy while on vacation. Within hours, he was feeling shitty, and during the night, became a veritable puke fountain. Weakness overtook him, and in his ill state, decided to call an end to his vacation and drive home. This effort was brought to an abrupt end due to the onset of hallucinations. These weren’t the oft-depicted whimsical, psilocybin mushroom-driven phantasms full of fairies, talking trees, and a feeling of oneness with the universe. No, this poor son of a bitch was sidelined by a waking nightmare full of visions of “aggressive and screaming animals.” His mellow thoroughly harshed, and now unable to drive on account of seeing giant fucking bugs outside of his car, the man thought it might be a good time to get some medical attention. All his vitals at the hospital seemed kosher, except for the part where he was losing his shit because he was having the worst trip of his life, and after a short stay, he came back to reality…apparently, and thankfully, completely unable to remember the psychological hell his maritime meal had put him through.

The second individual outlined in the publication was a 90-year old man who purchased the Salema porgy from a local fisherman in 2002. Little did he know that his sweet, elderly soul was about to be catapulted through the stratosphere and straight into Never Never-do-I-ever-want-to-be-this-high-again Land.

Fish market? More like Phish market.

Within hours, he was bulldozed by auditory hallucinations consisting of human screaming and “bird squeals.” The retiree was apparently too terrified that the hallucinations were part of the sudden onset of a psychotic episode or mental illness that he told no one for the remaining three days of symptoms, which included frequent nightmares in addition to the general feeling of going bugfuck insane during waking life. It was only afterward that he recalled someone at the fish market saying something along the lines of “oh, just so you know…these fish are tasty but they can sometimes cage you in loop of mirrored realms full of hatred and the shrieking of dying universes” and decided to contact someone at the local poison control center.

Of course, the Salema porgy isn’t the only hallucinogenic fish out there. Sporadic records come from numerous other groups of fish, and one of these are the rabbitfishes. Rabbitfish, or “spinefoots”, are a group of fish native to the warm waters of the Indo-Pacific, and belong to the genus Siganus. The fish have a unique modification of the rear-facing fins; well-developed venom glands attached to spines making up the framework of the fin. These venomous barbs can be used defensively (and if the venom is used against humans, is not deadly, but can inflict excruciating pain), and are the origin of the decidedly more intimidating “spinefoot” common name.

“Do it. Call me Peter Cottontail one more time, buddy, and I’ll send you to the hospital.”

Despite their rather nasty pokey bits, rabbitfish are commonly fished for food by humans who live along the coral-lined shores of tropical coasts and islands. With consumption of these little, herbivorous reef fish comes the risk of hallucinatory poisoning. Residents of the Mascarane Islands (particularly Mauritius and Réunion) in the Indian Ocean, east of Madagascar, have reported regular, occasional instances of fish poisonings with symptoms consistent with the ichthyoallyeinotoxism seen with Salema porgy in the Mediterranean; loss of balance and equilibrium, nightmares, hallucinations, and mental depression, all in an absence of major peripheral neurological distress (usually associated with more typical (and serious) exposures to neurotoxins from food; trouble breathing, sweating, blurred vision, etc.). Apparently, the people of Mauritius and Réunion have been aware of this unique property of Siganus fish for some time now (enough so so that one species, Siganus spinus, is consistently referred to as “the fish that inebriates”), and local fishermen have associated elevated risk with certain times of the year in their archipelago home, and can avoid inadvertently taking a surprise trip to see just how far down the rabbitfish hole goes…

There are also records of hallucinatory poisoning by rabbitfish in the Mediterranean; specifically by the dusky spinefoot (Siganus luridus). This fish is native to the Western Indian Ocean, Red Sea, and Persian Gulf, but has been introduced across the Suez Canal in recent decades, although the symptoms were also similar to more “conventional” poisoning by ciguatoxins and maitotoxins (which cause ciguatera; a seafood-borne intoxication derived from ciguatoxins from single-celled marine algae which become aggregated in the flesh of food fish…most commonly associated with big, tropical, carnivorous fish like grouper, barracuda, snapper, and amberjacks).

Over on the other side of the globe, out in the West and Central Pacific, ichthyoallyeinotoxism is also implicated in hallucinatory poisonings, but often with different groups of fish.

Mullets (Mugilidae), odd, flat-headed fish found in warm waters the world over, have been reported to be ichthyoallyeinotoxic here in Hawai`i, as well as in the Micronesian islands of Kiribati. The toxins appear to concentrated in the head of the fish, specifically. At least some residents of the Republic of Kiribati, in recent times, would consume mullet heads with the intention of getting really fucking high. The hope was that eating a nice, fishy meal, kicking back on a tropical beach, and, er, “chasing the saltwater dragon” would allow for pleasurable hallucinations and vivid, otherworldly dreams.

Also, particularly in Kiribati, coral groupers (Epinephelus corallicola) and the banded sergeant-major (Abudefduf septemfasciatus) have been reported to occasionally cause hallucinogenic episodes, specifically in older members of the local population (the only age group that eats these species customarily; kind of like butterscotch hard candy and prunes here in the U.S.). Although, since only senior citizens eat these fish, and the high was described as a kind of “forgetfulness”, it’s not clear whether or not the issue is inebriation or run-of-the-mill senility. Then again, if people were accusing my old ass of spending my Golden Years getting toasty off the silly sushi, I might get awfully “forgetful” myself.
“What?! No, grandson, of course I’m not a stoner! That’s just Alzheimer’s.”

Sea chubs of the genus Kyphosus (pictured below), commonly eaten in Hawai`i in historical times (less so recently), have also been reported to induce intense hallucinations in diners.


Similarly in Hawai`i, convict tang (Acanthurus triostegus), a species of surgeonfish found throughout the Indo-Pacific, has been associated with ichthyoallyeinotoxic poisonings. The species (known as “manini” here in the islands) is abundant in nearshore reef habitat, and is readily identifiable by its markings, which resemble the stereotypical stripes of an inmate’s jumpsuit uniform…a criminal sentence most likely endured due to the fish spreading the scourge of drugs across their ecosystem.

Crime doesn’t pay.

So what is behind these hallucinogenic compounds? Why are only a limited group of fish associated with ichthyoallyeinotoxism, and why does it seem to only effect people relatively rarely? Other sources of hallucinogens in nature are, by and large, far more predictable than this. There may be variances in dosage between individuals, but many times, particular, entire species are known to have hallucinogenic qualities. Examples of these abound. Psilocybin or “magic” mushrooms and ergot (from which ergotamine, and eventually LSD, were isolated) are the hallmark psychedelics of the Fungi kingdom. The number of psychedelic plant alkaloids and other compounds, many of which play spiritual and cultural roles in societies around the globe, is incredibly high: mescaline from cactus (including peyote), bizarre and terrifically potent terpenoids like salvinorin A from the famed diviner’s sage, and DMT from dozens of vines and shrubs, are just a few major examples. DMT variants found in the toxic secretions of toads like Bufo alvarius also have consistently extremely psychoactive, hallucinatory properties. If we can identify specific plants, fungi, and animals that produce hallucinogenic effects, then what’s the deal with the weird, wishy-washyness of these hallucinogenic fish?

Since ichthyoallyeinotoxism is not a very common variety of food fish poisoning, and it presents so variably, we don’t really know much about it, or what is actually causing it, specifically. But, given how the phenomenon appears to be temporal, tied to seasonality in some locations, and is so highly variable, it is thought that the source is dietary. The fish are getting the toxins from their food, and much like with the mercury so many of us are familiar with, accumulating the stuff in their tissues. Since so many species that are causing these effects are herbivorous, it is likely the original source is marine algae.

This is strikingly similar to the most common form of poisoning from food fish, ciguatera. Ciguatera is caused by the uptake of a specific group of microscopic algae; dinoflagellates (chiefly the species Gambierdiscus toxicus). It accumulates in the food chain, compunding as one ascends, so that reef predators have the highest concentration of the toxins in their flesh (and are therefore most commonly reported to cause severe poisonings when consumed). Ichthyoallyeinotoxism does have a quite a bit of suspicious overlap with ciguatera, and it’s often hard to tell the two ailments apart from one another. For one, the species of fish that cause hallucinogenic poisonings are also commonly associated with ciguatera records as well. Secondly, the symptoms are incredibly similar, and both impact the nervous system in a myriad of bizarre ways. These similarities, and the lack of a specific source of the much rarer ichthyoallyeinotoxism has led some to believe that ichthyoallyeinotoxism is just one manifestation of ciguatera (which is caused by several known algal toxins).

However, the two maladies have distinct differences as well. Ciguatera is typically accompanied by furious digestive problems, muscle pains, lots of weird disruption of the peripheral nervous system (reversal of hot and cold sensations, electric charge sensations, and numbness) and only mild to occasional instances of hallucinations, whereas ichthyoallyeinotoxism has benign bodily impacts, with most effects on the central nervous system (the brain itself, leading to the hallucinations and nightmares). Also, ciguatera is notorious for long-term, pernicious effects, which can be severe enough to cause disability a decade or more out from the initial poisoning. Ichthyoallyeinotoxism, in contrast, abates completely within a few days with no reported latent effects in weeks, months, or years down the line. Hallucinogenic poisoning also turns up in places not typically associated with the normal range of the algae associated with ciguatera, like the Mediterranean (ciguatera tends to crop up most typically in the Caribbean and Pacific regions).

Others have postulated that the toxins might have their own, separate origins in algae like Caulerpawhich are habitually consumed by many of the more commonly hallucinogenic fish species.

Whatever is causing the occasional flaky, delicious acid trip in tepid seas, it shouldn’t be of huge concern to anyone reading this (or object of recreational interest; good luck successfully being lucky enough to be in the right place at the right time). Ichthyoallyeinotoxism remains an uncommon and enigmatic phenomenon, far less so than ciguatera or red tide shellfish poisoning (which are still not all that common, thanks partially to awareness campaigns and harvesting advisories during algal blooms). Mercury toxicity shouldn’t really be high on your list….that is, unless you are pregnant, or insist on eating canned tuna by the flat.

Honestly, the real source of caution seafood lovers such as myself should take is towards regulation of consumption. Many fisheries of popular food fish (Pacific bluefin tuna comes to mind) have been subject to extreme population reductions and are threatened with collapse. The effects not only impact human culinary lives and employment, but inevitably reverberate through entire marine ecosystems. Some stocks are in better shape than others, and are harvested in more sustainable ways than others. If you want to be selective with your seafood choices, your time and effort might be better spent keeping conservation in mind, not the risk of turning your mundane Thursday night into a disorienting, hallucinatory hellscape.

Image credits: Phish concert image, rabbitfish, sea chub (John Turnbull), convict tang

Intro image composite, modified from the following: Lionfish (Michael Aston), pufferfish, mandarin fish (Klaus Stiefel), lagoon triggerfish (Michelle Bender)

© 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: Vinegaroons

This post is the sixth in an ongoing series on arachnids. Previously, this series addressed whipspiders, hooded tickspiderspseudoscorpionsharvestmen and solifugids. Additional posts on other weird, often overlooked or neglected groups of these creepy crawlies to follow. For a related chelicerate, but as far as science can tell, not an arachnid, see the post on sea spiders.

The vinegaroon.

By now, if you’ve been reading my continually-updated series on the underappreciated and less diverse groups of arachnids, you will have been exposed to an assembly of bizarre creepy-crawlies; among them, “headless” hooded tickspiders, library-squatting pseudoscorpions, manic, ever-hungry solifugids, family-oriented amblypygids, and amputation-prone harvestmen. Weird as these groups all are, few compete with the strangeness of the arachnids known as “whipscorpions”, “uropygids”, or “vinegaroons.”

These arachnids are members of the order Thelyphonida, a small group of arachnids comprised of only 100 species, dwarfed by larger orders like the Araneae (spiders, with more than 40,000 species) and the Scorpiones (“true scorpions”, with about 1,700 species). The order used to be incorporated in a now defunct classification known as Uropygi (which also included small, close relatives known as “microwhipscorpions”). “Uropygi” basically means “tail rump” or “tail rear” in Greek, which refers to the arachnids’ curious, thin, segmented “tail” extending from the back of their abdomen. It is this tail, or “whip”, combined with their general scorpion-like body shape, which is key to the origin of one of their common names; the “whipscorpion.” They are also known by their third common name, used frequently throughout the Americas, “vinegaroon”, which alternatively sounds like the most foul tasting Girl Scout cookie ever.

“Oh…oh god. What have I done?”

While vinegaroons have a scorpion-like body shape, with their flat, extended abdomens and spiky, clawed pedipalps (those pincer appendages in front of the face), they are not closely related to scorpions at all. As far as we can tell, they are most closely related to things like amblypygids and spiders, and are in a separate subdivision from things like scorpions, camel spiders, and daddy-longlegs, which make up a proposed grouping called Dromopoda.

Vinegaroons are found in the warmer latitudes of North America, throughout Central and South America, as well as subtropical and tropical Asia (and a lone species found in tropical Africa). The center of their diversity appears to be in Southeast Asia. They, in true arachnid form, like to hunker down in humid, dark places, which usually requires clawing out a burrow in the dirt with their pedipalps. Many species are found in forest habitats of varying moisture, but some live in arid habitats. One of these is the largest species of vinegaroon, Mastigoproctus giganteus, with a body about as long as a credit card, which lives comfortably in the desert and semi-arid tracts of the southern U.S. and Mexico, but tends to only be active during the wetter months of the year.

Vinegaroons are entirely nocturnal, and emerge from their dank holes in the earth nightly to stalk hungrily and ominously over the Land of the Tiny. They are exclusively carnivorous, and feed primarily upon other arthropods, like crickets, cockroaches, and millipedes, which they pin down with their beefy, scorpion-like, wire-cutter pedipalps. They are also equipped with a sharp spine on the inside surface of the claw, which is more or less a barb, immobilizing the prey and paving the way for the merciless crushing of their prey’s brittle exoskeleton, allowing the vinegaroon to leisurely lap up the critter’s hemorrhaging fluids like a cat at a water dish.

The hard part, though, is finding the food in the first place. Vinegaroons have eight small eyes, two at the front of the head segment (the prosoma) and three flanking each side, but the eyesight they provide is so fucking poor the worthless things might as well be pimples. To make up for their myopic failings, vinegaroons successfully navigate their witching hour escapades by tactile mastery. They, much like their distant cousins the camel spiders (solifugids), only use their hind three pairs of legs for walking; their front pair have evolved into long, thin, highly-sensitive feelers that scan the ground in front of the vinegaroon. It would seem that somewhere early in its evolution, the vinegaroon must have looked at insects and their antennae with much envy, because these modified front limbs look like the imitation, off-brand version of what everything from beetles to bumblebees have been proudly waving around on their heads for eons. In this way, vinegaroons sense their environment similarly to their close relatives, the amblypygids, using their delicate front limbs as a pair of white canes. Further contributing to sensory input is their “tail”, a long, straight, segmented rod (also referred to as a “telson”, which is a term also used for the “tail” of crustaceans like lobsters and shrimp). The telson is used to feel around at the back of the animal, and surely functions as an adaptive safeguard against the “Kick Me” sign prank.

But woe be unto those who dare to stray too close to the vinegaroon’s caboose. These arachnids don’t have the venomous bite of spiders at the front, nor the deadly sting of scorpions at the back. Their pedipalps can deliver a bit of pinch, and the worst their telson can do is give a gentle tickle. It would appear as though the vinegaroon is something of a sitting duck, nothing but a helpless, crunchy, eight-legged chicken nugget for the world’s passing raccoons and lizards to casually inhale. But the vinegaroon has a unique trick up its sleeve geared towards keeping it unharassed and uneaten.

The vinegaroon is a squirter.

Vinegaroons are armed with glands located right at the junction of the rear body segment (the abdominal segment, or “opisthoma”) and the base of the telson. These glands (the “pygidial glands”) produce a liquid mixture of a number of chemical compounds, but the stuff is primarily acetic acid and caprylic acid in many species. You may know acetic acid as the key ingredient in vinegar, which is essentially 5% acetic acid by volume, which gives it its sour taste and characteristic odor. When threatened, vinegaroons jettison the watery contents of these glands through a pair of pivoting turrets, mounted on either side of the base of the telson in a spurt that can each about a foot away in any direction. With just enough agitation, the vinegaroon contracts the muscles around its dual tanks, and lets the cocktail loose, sending a wild, flailing stream of vengeance arcing through the heavens, like some drunk bastard using a urinal during an earthquake. It is the resulting noxious stink from these acidic emissions, reminiscent of common, household vinegar, that is at the origin of the “vinegaroon” name. The smell is particularly strong due to the concentration of acetic acid in the spray, which can be 15 times more concentrated than in vinegar. The video embedded below shows how this spraying looks up close, at around 2 minutes in:

I can hear the scoffing already. Really? That’s the defensive response? A stinky water gun? What’s it going to do, turn an attacker into a pickle? Some scorpions, like those of the “man-killer” genus Androctonushave such horrifically venomous stings, that a defensive strike can incapacitate or kill animals as large as humans. Some spiders, like the Sydney funnel-web, can potentially deep-six your ass if it insists on getting bitey. But the vinegaroon’s so-called “defensive behavior” has all the ferocity of an infirm chihuahua dribbling on a carpet. Other arachnids can do wonderfully nasty, painful things to get predators to turn tail…while this firehose-assed jackoff over here is what, adding zest to a salad at Olive Garden? What would a vinegaroon-themed supervillain even do? Terrorize reservoirs of baking soda sitting underneath paper mâché mountains?

“Oh, human, you will rue the day you picked up the Sprinkle Master…prepared to be….wetted…”

The vinegaroon’s pungent piddling isn’t just an uncomfortable distraction; it is actually a well-honed deterrent. For one, the dual flesh faucets that spray the jet of chemicals can be rotated in just about any direction, and can quickly be aimed relatively accurately in the direction of a harasser. The goal isn’t to get the predator to wrinkle its nose and recoil at the sour stink, but to get the ass spritz into the eyes, nose, and mouth. This is a strategy not unlike what spitting cobras employ for dissuading aggressors. The spray, in most species, isn’t concentrated enough to do much to skin, especially if that skin is covered in fur. But the acid mixture is irritating to mucous membranes, and a shot of this crap in the mug will go over like lemon juice eye drops and jalapeno mouthwash. The shit burns.
There’s also evidence of the presence of 2-ketones in the sprays of some species of vinegaroon, specifically 2-heptanone, 2-octanone, and 2-nonanone…all of which can function as potent organic solvents. The presence of these solvents (which help dissolve organic compounds, like the acetic acid, in other organic compounds…which includes everything you are made out of) in the sprays has shown to increase the effectiveness of the acetic acid, with the spray actually managing to briefly sting human skin. The 2-ketones act as an “enhancer” for what is normally a benign acid for large animals.

If the proctological can of Mace doesn’t work, there’s always good, old-fashioned claw clappin’ and scrappin’. The pedipalp pincers aren’t deadly to anything larger than a house key, but a nip on the face of a lunging mammalian assailant might be enough to convince them to reconsider. When threatened, vinegaroons will normally strike a defensive pose with their pedipalps outstretched and ready to tussle, with their opisthoma and telson arched, prepared to turn on the Pain Sprinkler.

“Come at me, bro. I can do this aaaallllll fucking day.”

Assuming these blind, wizzing wizards fend off enough toothy jaws with their stanky squirts to make it to adulthood, they can get right on with the baby making…but not before an arduous courtship display.

Vinegaroons engage in an exhausting, complicated, 13+ hour-long marathon of multi-stage foreplay prior to getting on with the rogering. It starts off with roving male encountering a female, and him chasing her down and grappling her with his pedipalps. The two of them then appear to spar with one another, gripping, shoving, and throwing each other around. It’s so….sweet? This bit of love wrasslin’ can be cut short at around a minute, or this stage, which may function as an evaluation of “worth” in a partner (“is he/she a good, strong mate?”), can continue for hours. If the female is receptive to a, errrr, “second date”, she’ll signal that they can proceed by sticking her first pair of sensory limbs in the mouthparts of the male and wiggling them back and forth. This acts as a “tap out”, and the couple proceeds to the next step in their relationship. At any point prior to this, she may signal that she’s not down to clown, and with a subtle, aggravated flick of her sensory legs, she peaces the fuck out and courtship ends.

The second phase involves dancing. Not even joking. The male still grips her delicate sensory limbs in his mouthparts (“chelicerae”), and, face to face, he drags her around, back and forth, using his muscular pedipalps. The female follows his lead, continuing to evaluate him as a mate. The sensual display is akin to something out of Dirty Dancing, except this version of the mambo has Jennifer Grey’s fists wedged deep in Patrick Swayze’s mouth. This part lasts somewhere on the order of three or four hours.

“Nobody puts Baby in a burrow.”

If both partners are still ready to continue towards the finish line, the male while have typically edged the two of them into a safer location (like a burrow). The male, still with the female’s sensory legs embraced by his mouthparts, rotates so that he’s now riding on top of her. They stay like this, poised awkwardly over each other like players in a game of Twister, for another several hours. During this time, the male manufactures a spermatophore (a dense sac of sperm) inside of his abdomen. When this is over, the male deposits his payload on the dirt in the form of rigid block of reproductive material. He then carefully maneuvers the female over the spermatophore, and takes the two attached sperm packets from the spermatophore framework, and shoves them into the female’s gonopore (genital opening). When the female is ready, she signals by opening her clawed pedipalps, and the male promptly releases her legs from his mouthparts, and wheels around to grasp her soft abdomen. For the next few hours, the male massages the sperm packets with his pedipalps, and it is thought that this helps the sperm actually disperse into the female’s reproductive tract. Eventually, the deed is done, and they uncouple and go their separate ways. Unlike in many other arachnid groups, post-coital cannibalism doesn’t really seem to be a thing in vinegaroons. After a casual boinking with a disproportionately passionate preamble, they mutually part paths.

The female then carries fertilized eggs inside of her for a few months. Before laying as many as three dozen eggs, she seals herself up in a burrow for safety. However, instead of laying a clutch that sits on the floor of the burrow, she contains them in the sac that adheres to the bottom surface of her opisthoma. She continues this voluntary house arrest for another few months. Did I mention that she refuses to eat? And that she arches her abdomen in such a way that the giant broodsac can’t touch the ground? FOR MONTHS. Say what you want about the difficulties of human gestation and what our mothers went through in pregnancy to birth all of us…but mama vinegaroons endure the equivalent of carrying around a garbage bag full of bowling balls with nothing but your clenched ass cheeks for an entire college semester.

“Oh, you do Kegels? That’s cute.”

Eventually the eggs develop into “post-embryos”, which is a name that doesn’t adequately illustrate how much these larval creatures look like albino, baby, gummy squids.

Tapioca pearls with legs. Lovely.

These baby vinegaroons climb onto their mother’s back, where they latch on for dear life with sucker-like organs. There they remain for yet another month. Eventually, they have their first molt, and begin to disperse away from the mother and begin foraging upon small insects and mites. Once seasonal rains arrive, and the young have all managed to develop hardened exoskeletons, the mother, famished, bursts out of her subterranean cocoon to get her fat reserves back up again. Much like their relatives, the whipspiders, vinegaroons engage in a higher level of maternal care than what is seen in many other arachnid orders. The mother will abstain from eating her babies unless in dire need of sustenance, and cohabitates with the young, first-molts in the burrow for a short while. Whether or not the mother, in nature, actually provides food for the young during this time is not currently known.

Thelyphonida, an enigmatic and rarely encountered order of arachnids, is represented by a single family in modern times. The vinegaroons are an ancient group, with fossilized, relatively unchanged representatives stretching back 350 million years (in the Carboniferous era), 100 million years before the earliest dinosaurs strode Earth. Today, only a small number of species are still around. These dark, glistening, hard-shelled, silent travelers of the night quietly assist in reducing numbers of pests like cockroaches and termites. These acrid skunks of the arachnid world are oddities, with their trifecta of sensory feelers and unusual acetic acid nozzles, and while they might appear dangerous or foreboding, if you are so lucky to encounter one in the wild, remember that the worst these little guys can do to you if you get too close is stink up your shoes.

Image credits: Intro image, vinegaroon in hand, defensive vinegaroonvinegaroons dancing, female vinegaroon carrying broodsac, vinegaroon with post-embryo young

© 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.