At this very moment, much of the United States (my home country) is winding down from celebrating the 240th anniversary of the signing of the Declaration of Independence. Out here where I live (Hawai’i), it’s still technically the Fourth of July. Americans seem to celebrate the intellectual founding of the country by falling somewhere on a spectrum that runs from quiet, appreciative reverence of the historical significance of today’s date on one end, to a booze-fired, red, white, and blue, testosterone-seeped fuckstorm of vociferous anthems, carbon emissions, and an arsenal of fireworks large enough to torch every forest in the tri-state area on the other. Personally, I decided to follow up on mowing down on charred, ketchup-lubed hotdogs (on this holiday, I call them “freedom weiners”) and update this blog with a series of posts through the coming couple of weeks as a means of celebration; a celebration of the lifeforms that make their home within the borders of the U.S. Below, I kick off addressing the first set of a total of twenty broad groupings of animals, plants, fungi, and other organisms, selecting a representative member of each group that 1) can be found in the United States, and 2) preferentially, is ONLY found in the wild in the U.S. (is entirely endemic). An example of a critter that satisfies both criteria is featured at the top of this blog post; that adorable heap of blubber and sunshine-powered bliss is the Hawaiian monk seal (Monachus schauinlandsi), which is found only in the insanely remote Hawaiian Archipelago (especially the uninhabited Northwestern Hawaiian Islands).

Why do this? America has a fantastic assemblage of biodiversity worth celebrating and protecting for future generations…and much of this biodiversity includes species that are NOT American symbols of wilderness like bald eagles, buffalo, and black bears. These organisms are typically secretive, rare, bizarre, and generally poorly understood by both science and the public. Acknowledging what we share our wild spaces with is fundamental for conservation, and too often, we neglect to appreciate the majority of organisms that aren’t charismatic, or marketable.

The twenty groupings (broken into three separate blog posts) are, admittedly, heavily biased towards vertebrates, more so towards animals in general, and even more so towards non-microscopic organisms. The groupings also are only partially rooted in taxonomic accuracy, and some are lumped in a seemingly arbitrary fashion for ease (for example, saltwater and freshwater fish separately, “reptiles” as a group). Some representatives are truly endemic to the United States. Others have geographic ranges that bleed over into other North American nations. Some groups of organisms, like fungi, almost never have restricted distributions in North America, so compromises were made when listing these kinds of representative lifeforms. Bacteria and other unicellular organisms were skipped entirely, due to their general tendency toward a global presence. So, yeah, I don’t have time for that cosmopolitan distribution shit.

With that out of the way, let’s get to meeting some of these illustrious Americans, starting with a modest sampling of vertebrates:

Mammal

The little guy above may look like your typical long-eared carrot mulcher, but the photo shows a unique species of rabbit. This is a pygmy rabbit (Brachylagus idahoensis), found only in the sagebrush-rich areas of the Great Basin and parts of the interior Mountain West, with populations ranging from Southern Oregon and Idaho, down into Nevada and Utah. A small, isolated population in Eastern Washington went extinct almost a decade ago, but the area is currently being repopulated with individuals with mixed genetic ancestry from the local area and a population in neighboring Idaho. Pygmy rabbits are unique in a number of ways. Firstly, they are the only North American rabbits to live in sagebrush habitat, subsist almost entirely upon sagebrush, and dig burrows. They are also the only known species in the genus Brachylagus, and are evolutionarily quite distinct from any other rabbit on the North American continent.

Oh, and did I mention they’re really goddamned tiny? Pygmy rabbits are the smallest species of rabbit on the planet. Adults only reach the size of a guinea pig, weighing about a pound at their heaviest. Given their miniature proportions, Brachylagus rabbits are literally Bugs Bunnies.

Reptile

The oblong dude above with the sour expression (probably from acting as a mount for a much smaller turtle) is the flattened musk turtle (Sternotherus depressus). Flattened musk turtles are found only in a single river drainage in central Alabama, and they are critically endangered. While their characteristically compressed carapaces makes them look like their real problem is crossing the highway in Chevy country, the true reason for their decline is a persistent loss and degradation of their already limited habitat.

Musk turtles, more generally speaking, are, alongside the mud turtles, members of the family Kinosternidae. These turtles are kind of a hallmark of North America, with much of their diversity seated in the southern and eastern U.S. and Mexico. Musk turtles (genus Sternotherus) are so named because when agitated, they can secrete a nasty-smelling musk fluid from an anal gland near the rear underside of their shell. Would-be predators aren’t likely to pursue Pepe le Poo after it fires back with a weaponized shart, allowing the musk turtle to make an aquatic escape.

Bird

Most of the songbirds (order Passeriformes) in the United States actually have huge geographical ranges when you account for the seasonal migrations they undertake as adults. Many songbirds only stick around in the cool, temperate zone found in much of the lower 48 for the most amiable time of year, and then book it for the tropics and subtropics long before the temperature plummets, food resources become locked in snow and ice, and White Walkers descend upon the Wall.

But some, like the black rosy finch (Leucosticte atrata) ain’t about that lily-livered life. Black rosy finches are found in the highest elevation locations in the central Rockies, ranging over a swath of mountainous territory in Idaho, Nevada, Wyoming, Montana, Utah, and Colorado. They breed high above the treeline in the alpine zone, scraping out a living among rocky, wind-blasted cliffs. Because of their Spartan surroundings, these birds tend to eat a lot more insects than other finches (which primarily target seeds), since so little greenery exists up in their frigid, stratosphere hangout. When winter comes, black rosy finches merely drop down in elevation, and hang out for a few months in protected, snowy valleys and open meadows. Humans rarely encounter them outside of this wintertime low-elevation “vacation.” Some may shift their range southwards a bit, but this pales in comparison to the thousands of miles of travel that other songbirds punish themselves with each year. Once spring graces their upland home again, these little hardasses take their itty-bitty selves back up to the frigid and lonely crown of the continent.

Amphibian

The cool, exceptionally wet old growth forests of Oregon and far Northern California are home to southern torrent salamanders (Rhyacotriton variegatus). Southern torrent salamanders are one of the four members of the single torrent salamander genus…the only genus in their entire family (Rhyacotritonidae). These pleasant little amphibians, as a group, range from the Olympic Peninsula in northwestern Washington state, down through the temperate rainforest corridor that lines the coastal and mountainous regions of Western Washington, Oregon, and Northwestern California. So, not only is the southern torrent salamander an endemic U.S. species, but it belongs to an entire family found only in the United States.

These patriots are picky, being superbly intolerant of anywhere drier or warmer than their preferred habitat of decaying vegetation and moss sitting next to a primeval, clear, babbling brook. Canopy cover seems to be the trick. The older and more shaded their habitat is, the happier the torrent salamanders end up.

Saltwater Fish

It is perhaps cheating to call on the State of Hawai’i to provide a saltwater fish species found entirely on reefs in U.S. waters, considering that about a quarter of all reef fish in the island chain are found nowhere else on Earth already…but I’m doing it anyways.

The uniquely patterned fish featured above is a male masked angelfish (Geniacanthus personatus), a denizen of the deeper reefs (below 25 meters (82 feet)) in the Hawaiian Archipelago…with the vast majority of individuals found in the hyper-isolated Northwestern Hawaiian Islands (much like the aforementioned Hawaiian monk seal). Females resemble the yellow-masked males somewhat, but instead have a black mask and no colored borders to the dorsal and anal fin.

Masked angelfish exist in a single, hard-to-access region of the globe…at depths not many are equipped to explore. So, seeing a masked angelfish in the flesh, in any capacity, is an exceptionally rare event for the majority of the world. Because of this, masked angelfish can fetch prices in the aquarium trade that are so stupidly high that they, somehow, have to be real. Tens of thousands of dollars for a single fucking fish. Yes, a single, rare, mostly white fish can sell for more than a brand new car. However, that may change soon, considering that the last few years have yielded breakthroughs in breeding this very species…a species that is coveted and priced like a precious stone…in captivity.

Freshwater Fish

The United States is privileged to host a number of weird, often ancient, endemic lineages of fish that travel up and down her extensive waterways. The bowfin (Amia calva) represents one of these lineages quite masterfully.

To understand the bowfin’s significance, in an evolutionary sense, it’s necessary to break down how bony fish (fish that ancestrally have a skeleton made of bone as adults, not cartilage, as is the case in sharks and rays) are related to one another. Bony fish initially can be split into two groups: Sarcopterygians and Actinopterygians. The former are the “fleshy-finned” group that includes the line that gave rise to land-dwelling tetrapods (and, eventually, you and me); today, this group also harbors the coelocanth and the lungfishes. Actinopterygians are all the “other” bony fish (also known as “ray-finned” fish), and represent the overwhelming bulk of fish diversity, as well as all the fish familiar to most people. Let me put it this way: I’d bet money that if I asked you to think of five random fish, all of them would be placed in the Actinopterygian column. Actinopterygians can be split again into two main subclasses: Chondrostei and Neopterygii. The Chondrostei includes fish that have retained a number of “primitive” features, and also have secondarily evolved a partially cartilagenous skeleton; this includes sturgeons, paddlefishes, and the strange, African bichirs. Neopterygiians, in contrast, are an extremely successful and species-rich group, with enhanced mobility and powerful, motile jaws compared to earlier offshoots of the fish ancestral line. This group breaks down, again, into two main infraclasses: Holostei and Teleostei. Members of the latter (teleosts) represent nearly all of the neopterygians currently alive. The Holostei retain a number of primitive traits, including vestigial spiracles (fully-functioning structures seen in chondrostei and sharks) and some aspects of their tail fins and scales. The Holostei include gars (order Leposteiformes), which are armored predatory fish native to the Americas that look like someone slammed a crocodile and a salmon together. The only other living Holostei fish, and closest living relatives of the gars, is the bowfin (order Amiiformes).

Only one species of bowfin has survived to the present. This thick-skulled, pick-toothed living fossil spends its time casually snapping up smaller, less evolutionarily-seasoned fish throughout the drainages of the Mississippi River and Great Lakes, as well as other areas all over the Eastern Seaboard of the U.S. It may be tempting to dismiss the bowfin as an anachronistic dinosaur, out of place in time, and only existing today as an accident of prehistory. But, doing so would quickly backfire, as the bowfin would illustrate that it’s the product of many millions of years of on-going evolutionary change, and that it has more than a few tricks up its soggy sleeves…one of which is the ability to breathe air. Similarly to a lungfish, bowfins can gulp air and extract the oxygen from it during times of low oxygen content in the water. So, laugh all you want at the bowfin’s out-of-date fin fashion and habits that haven’t been hip in hundreds of millions of years, this fucking thing refuses to die in conditions that would quickly asphyxiate any other new, high-falutin’, Millennial fish.

This post series will continue with some invertebrate representatives from the United States in Part 2, and eventually fungi and plants in Part 3.

Image credits: Monk seal introductory photo, pygmy rabbit, flattened musk turtle, black rosy finch, southern torrent salamander, masked angelfish, bowfin

© Jacob Buehler and “Shit You Didn’t Know About Biology”, 2012-2016. 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.