The British explorer Samuel Hearne, while trekking across the Canadian Arctic in the late 1800’s, was amazed to find frozen, lifeless frogs folded under the snow and leaf litter. “Their legs are as easily broken off as a pipe-stem,” wrote Hearne, who was apparently a malevolent 6-year old. “But by wrapping them up in warm skins, and exposing them to a slow fire, they soon recover life.” He had discovered the amazing cryonic frog.
The wood frog of North America lives in the Northeastern United States, Canada, and almost all of Alaska. It breeds in vernal pools, those ephemeral forest ponds filled with spring snowmelt, where its young tadpoles are free from predation by fish. They have superb camouflage for blending in with the leaf litter on the forest floor, and are even capable of morphing their color, lighter or darker, to disappear into any shade of loam. (I might add, having listened to their peeping in the vernal pools of Massachusetts, that they are to April what crickets are to July, the sopranos of the season.)
But by far the most extraordinary thing about the wood frog is its ability to freeze itself and remain alive, which has given it the ability to go where no amphibian has gone before. The first frost sets off a remarkable chain reaction in the frog’s body; at a mere touch of ice, the frog allows its skin cells to freeze over. By the time the transformation is through, the frogsicle has no heartbeat, no brain activity, no breath. Technically, it is dead. It can stay a lifeless corpse all winter, and as long as no more than 65% of its body is frozen, it will thaw itself out in the spring, kickstart its brain and heart, and within a few hours, get down to the business of shagging other little wood frogs in the vernal pools. What’s more, this miraculous resurrection is done without the aid of any coffee whatsoever.
Underground! From rabbit warrens to nuclear fallout shelters, it’s a great place to hide out. If you’re a terrestrial vertebrate, the safest place you could conceivably be is underground, where you’re protected by a temperature-stable bunker, an ocean of dirt, rocks, and roots. But it’s one thing to dig a burrow, and another to spend all your time underground, swimming through the soil. If you’re a full-time tunneler, there are really just two body types you can evolve to fit: the “mole” model, and the “earthworm” model.
Consider the difficulties of underground travel. You don’t want to be too large, or digging would be exhausting. You don’t want large eyes, which would be useless and become full of grit. You’ll need a keen sense of smell and touch, as you’re likely to be finding food by chemical and tactile signals rather than visual ones. This star-nosed mole from North America is a great example of the mole archetype: small, compact, wedge-shaped, with sealed-off eyes and ears, powerful front claws, and 22 fleshy appendages that are among the most sensitive touch receptors in the animal kingdom. Star-nosed moles are true swimmers; they breaststroke through soil, but are also quite adept at catching prey in the water. Moles are insectivores, related to that most ancient of mammals, the shrew. But thanks to the awesome power of convergent evolution, you don’t have to be related to the moles to become a mole.
I can’t tell whether it’s the advent of Halloween or these particular midterm elections, but witches have been on everyone’s mind lately. Until I was about 9 years old, I grew up near Salem, Massachusetts, the ground zero of American witchcraft, so I happen to know a few things about brides of Satan. I remember poring through an old book about the origins of Halloween around that time and staring at an illustration of the source of the myth about flying broomsticks. I wasn’t sure quite what I was seeing, but I got the sense that I was somehow less innocent for seeing it.
Have you ever watched a neighborhood game of Quidditch and wondered, Ow, doesn’t that totally hurt their nards? If you’ve ever ridden a professional racing bike, imagine the seat of that bicycle in your crotch as you swoop and dive at several thousand feet; the average witch’s nightly commute would feel like a series of hits to the junk with a whiffle bat. It turns out, there’s a reason witches fly bareback instead of saddled. The “flying” practiced by real witches was closer to what we call “tripping.” During coven rituals, women would apply hallucinogenic ointments which numbed the flesh and produced the sensation of flying. An anesthetic rubbed on bare feet created the illusion of lift-off, and a mash of mandrake root, full of psychoactive alkaloids, gave the women visions of delivering packages around Japan on a sunny afternoon (good trip) or flying through a tornado and having a house dropped on them (bad trip). But the drug couldn’t be ingested orally; that would be nauseating as well as slow-working. The most effective way to absorb the alkaloids was through the mucous membrane of the labia, applied to a wooden shaft of some kind. This is how a 9-year old boy in a public library found a picture of a bunch of naked ladies galloping around the room with broomsticks rubbing their hoo-has, high off their asses, and how I discovered the true meaning of Halloween.
But “flying ointment” was not always pure mandrake. Other varieties of hallucinogens were added to the recipe, including ergot, that psychoactive fungus which got the witches of Salem in such hot water. And I have heard tell that some recipes included the poison of the common toad, that eternal emblem of Halloween. Those rumors are at least mostly false. But the truth about psychoactive toads, as always with truth, is stranger than fiction.
At first glance, Pseudis paradoxa looks like the most normal frog in the world. It’s green, it lives in the water, it buries itself in mud, and it eats flies. Nothing particularly unusual about it. Until you meet its monstrous offspring.
That’s the P. paradoxa tadpole. And this is the adult and the tadpole next to one another:
The tadpole is almost four times larger than the adult; while adults measure about 3 inches long, their offspring can grow to 10 inches long. And there’s the mystery behind the Paradoxical Frog. There are invertebrates in the world which are larger in their larval stage, metamorphosing from chubby caterpillars to svelte butterflies. But this is the only vertebrate whose offspring is larger than its adults, and we have no idea why. And as long as science can’t yet explain it, why not indulge the urge to irresponsibly hypothesize?
You will probably never see a purple frog. In order to see a purple frog, you very much have to be in the right place at the right time. The place: a tiny fraction of a tiny but biologically rich mountain range in Southern India called the Western Ghats. The time: the summer monsoons. If you come to the Western Ghats in October, or go anywhere else but that few hundred square miles of wet plateau in June, you and the purple frog will miss each other entirely.
It is a great round blob of an animal, the purple frog, with a hard, beak-like nose for breaking into termite tunnels. Its eyes seem too small, its stance pigeon-toed, its call sounds like that of a chicken. It is such an unusual animal that it’s surprising it wasn’t discovered until 2003. The reason it remained hidden so long is that the purple frog is subterranean, burying itself alive for most of the year until it hears the drumming of the monsoon rains on the earth above, and clambers up to the surface to mate.
The Art of being Buried Alive is not an easy one to master. It requires you to slow your metabolism to a crawl, to live as if hibernating, but without being asleep. It is a self-imprisonment during which you cannot dare to plan your escape, or you will go mad. I imagine you can’t think at all. The purple frog is not in complete stasis: it hunts termites, its heart beats. But mainly, it squats in the dirt and listens. Who knows if the purple frog’s mind remains safely dreamless and null as it waits in the earth. Perhaps it does nothing but dream.
This waking hibernation has a name: estivation. For most animals that employ it, estivation happens during the dry summer months, but the Indian monsoon season starting in June makes the purple frog’s cycle unusual. Consider the lungfishes, those ancient and air-breathing fish whose shallow ponds which, for much of the year, do not exist. That’s right: there is a fish that can survive in a lake with no water. During the dry season, the lungfish buries itself in the mud, coats itself in a mucus cocoon, slows its breathing rate down to next-to-nothing, and estivates. It is awake. It waits for rain.
It’s been a long, dry summer.
You know what’s been on my mind lately? Midgets. Well, dwarfs. Well, actually, pygmies. I’ve been considering a post about pygmy animals for a while, and as luck would have it, a research team in Borneo just found this miniscule marvel:
Yes, that’s an adult frog. (If it weren’t, it’d be a tadpole, silly.) Measuring only 12 mm, the male Microhyla nepenthicola is the smallest frog in Europe, Africa, or Asia — though, amazingly, there are two species in the Americas that are even tinier. M. nepenthicola‘s species name comes from the Nepenthes pitcher plants it inhabits to keep its skin wet. It might never have been found if it weren’t for its loud, rasping call, which conjures for me an image of a puzzled biologist putting his ear to a pitcher plant like a dog to a Victrola gramophone, wondering why it was croaking.
As megafauna ourselves, I think most humans have this idea that species are trying to evolve to be larger, but are somehow limited. But the fact is that being small has its advantages, and many species are more than willing to become miniaturized to seize the opportunities that can only be found once you breach the microcosmos.
The other day we discussed adaptive radiation, the process by which a single ancestor can split into an aardvark, an elephant, a manatee and a mole. But how do species split from one another? Usually by being physically separated for a good amount of time. The obvious illustration would be a species radiating between islands, but “islands” can occur on land, too. Even within islands.
Rodents Of Unusual Size? I don’t think they… oh, there’s one.
Meet the Bosavi Woolly Rat, a cuddly cat-sized rodent and the largest rat in the world. What makes it remarkable isn’t just its size, but its location. It was discovered only last year in the Bosavi volcanic crater in Papua New Guinea, along with at least 40 other amazing animal species heretofore unknown to science and native only to this one crater, including a fanged frog, a fish that “grunts,” a marsupial called the Bosavi silky cuscus, a tree kangaroo, a new family of sleestaks, an ogre-faced spider that fishes for its prey, a new species of bat, the world’s smallest parrot, a new bird-of-paradise and caterpillars that collaborate to look like a snake. These creatures had no fear of humans, having probably never seen one before. After all, they’ve been walled inside an extinct volcano for 200,000 years.