Featured Creature Friday: Remarkable Rats

Photo courtesy of National Parks Service

Photo courtesy of National Parks Service

Okay, I know, the Featured Creature is usually about animals a little more exotic than your average rat. We’ve lived with rats (some of us even voluntarily), we’ve used them extensively for a very long time as research subjects, we’ve helped them spread all over the world and destroy fragile island ecosystems… what more could there possibly be to say about rats? Well, I thought this week with our Featured Creature it might be fun to try something a little different and offer you a collection of interesting links for things you might not know about a well-known sort of creature. You might be surprised, for instance, with a few of rats’ less-publicized qualities and talents, like empathy and even altruism. A study published a few years ago showed that rats will free their captive brethren, if they’re able, even if there isn’t any sort of actual reward in it for them. They may even save the captive some of their food, which if you ask me is a clear signal of good feelings from any species. (I mean I could share my Cheetos with you, but signs point to no.) Rats will also remember who’s helped them before, and are more likely to help other rats who’ve helped them. They aren’t just helping each other, though; what’s got me really excited this week is how rats are helping us. Non-profit organization APOPO is training rats and their handlers to do incredibly important work: detecting tuberculosis, and searching out hidden landmines. Sure, they don’t do that work spontaneously, they didn’t just wander into a lab one day and ask to be pointed at the tuberculosis test samples. But they’re stunningly good at the work. A single Giant Pouched Rat can check more TB samples in ten minutes than a lab technician can manage in a day… and the rats have a better accuracy rate, too, which has resulted in many previously undiagnosed TB patients being able to get life-saving medical treatment. You can’t beat these rats for mine detection, either. They’re light enough that even if they step directly on a landmine, they won’t set it off, and they’ve proved to be more efficient than mine-detection dogs at doing the work.

Rats may be one of those species that is likely to not only to survive the apocalypse but probably thrive in the midst of it — in the UK, for instance, they’re dealing not just with giant “mega-rats” but mega-rats that are immune to rat poison — but in the present they’re not just pests or pets, they’re doing an awful lot to improve our world, too. And when the inevitable world-ending cataclysm occurs, I for one would like to welcome our new mega-rat overlords.


Featured Creature Friday: The Cunning Cookiecutter Shark

Coming soon to Discovery Channel: Kaiju Week! Kaiju: Fact or Fiction? Kaiju: You Can't Prove They Aren't Real. (Image from Pacific Rim.)

Coming soon to Discovery Channel: Kaiju Week! Kaiju: Fact or Fiction? Kaiju: You Can’t Prove They Aren’t Real. (Image from Pacific Rim. Go see it, it’s awesome, there are robots punching monsters.)

Friends, you know I’m no fan of the ocean, primarily because there are jellyfish in there. Sure, the world’s oceans are full of strange, wild, beautiful creatures that frankly boggle the imagination, but the fact is that the majority of them wouldn’t mind feasting on your delicate human flesh. So generally I don’t like to think about what may be lurking in the depths of the sea, waiting to make a meal of us all. I try to ignore the terrifying existence of everyday, supposedly mundane animals like venomous sea snakes, stinging jellyfish, deadly rays, and saltwater crocodiles. (Saltwater. Crocodiles. So wrong.) It’s not even remotely a comfort to me to know that the world’s oceans are still for the most part an unexplored frontier, housing who knows what kind of horrors. You might think you just need to worry about the things science can verify, when the fact is that there could be shrieking eels. Kaiju. Cthulhu. You don’t know.

Barring a third or fourth viewing of Pacific Rim, though — and I mean, who wouldn’t want that? — if you’re interested in learning what oceanic monsters you should be terrified of at the moment, you’re pretty much left with Shark Week. And since the Discovery Channel seems to be getting into shrieking eel territory with their ridiculous Megalodon non-documentary, I thought I’d join the effort to bring the Shark Week tradition back to its old-school roots by telling you about an interesting, unassuming little shark that’s actually swimming around in the warm waters of the world’s oceans right now.

Cookiecutter sharks don’t look like much: they’re under two feet long, an unassuming brownish color, and used to be known by the yawn-worthy moniker of “cigar sharks.” The name doesn’t exactly seem menacing, either, like maybe they’re the peaceful bakers of the shark world, cheerfully decorating sugar cookies while the rest of their fellows tear penguins apart or whatever.

The cookiecutter shark uses its "who me? But I'm ADORABLE!" face as just one of its many weapons. (Image by NOAA.)

The cookiecutter shark uses its “who me? But I’m ADORABLE!” face as just one of its many weapons. (Image by NOAA.)

Don’t let cookiecutter sharks fool you, though. They’re still sharks. They’re also total assholes.

Their huge green eyes and silly-shaped mouth might look like the kind of result you’d get if you asked an anime artist to draw you a super-cute fish, but it’s all just part of their arsenal of attack weapons. What other tricks do they have up their fins, you wonder? Well, for one thing, they’re sneaky as hell. They’ve got a dark collar around their necks that makes them look like a little, tasty fish, and they’ve got bright green photophores (light-emitting organs) on their bellies  — they’re the brightest of the light-up sharks known to science — which, as seen from below, practically makes the rest of their bodies invisible. This helps them get the drop on their prey.

When it comes to the actual attack, they’ve got some serious adaptations on their side. Relative to body size, they have the largest set of teeth of any known shark. The lower row of teeth actually interlock to form a surface very much like a saw blade. (When they shed teeth, as sharks are wont to do, they shed that entire row at once. And what do they do with their saw-blade row of teeth when they shed it? They swallow the entire thing, like total bad-asses, so their bodies can recycle the calcium.) They’ve also got a set of lips that act like a suction cup. Why a suction cup, you ask?

Well, the cookiecutter shark likes to aim big. Unlike a lot of other sharks, it doesn’t just go after the kind of prey that can actually fit in its mouth. Sure, it’ll eat squids and whatnot, but what it’s really known for is taking a bite out of animals much larger than it is. It ambushes them with the help of its sneaky bio-luminescent trickery, latches on with its suction-y mouth, sinks in those sizable teeth, and then twists itself while its lower jaw vibrates like an electric carving knife, slicing a neat disc of flesh away from its prey.

Scars and wounds from the cookiecutter’s bite have been found on whales, dolphins, sharks, seals, large fish, stingrays, and people. These things prey on everyone equally, including the terrifying bad-asses of the sea like great white sharks, sperm whales, and leopard seals. They’re also known to travel in schools, so an animal that falls victim to a cookiecutter attack might end up looking like a crop circle diagram. Attacks on humans are rare, though they do occasionally happen, while other species are positively plagued by cookiecutters; nearly every adult spinner dolphin off Hawaii carries the marks of the cookiecutter’s parasitic predation, and beached whales have been seen bearing hundreds of bites. Cookiecutters have also been known to chow down on submarines, underwater cables, fishing nets, and oceanographic equipment, which could be attributed to them mistaking those things for prey but personally I think they do it to be dicks.

They’re apparently elusive enough that video footage of cookiecutters in their native habitats isn’t really a thing that exists, but the BBC put together a pretty great CGI simulation that shows how their hunting technique works:

(BBC Worldwide)

Unlike a great many of the world’s sharks, the cookiecutter isn’t endangered; it’s widespread and doesn’t face significant pressures on its population, which is sort of a good news/bad news situation on the shark conservation front. It’s like, yay, a shark species we aren’t hunting into oblivion, whooo! Bad news, it thinks the endangered sharks are delicious.

Featured Creature Friday: The Punishing Pistol Shrimp

I don’t know about any of you, but I don’t give shrimp much thought. Sure, they’re an essential part of ocean ecosystems, but I don’t even enjoy eating them, and I certainly don’t want them anywhere near my cocktails, so for the most part they’re not even on my radar, so to speak. If I’m thinking about the oceans I’m usually pondering the terrifying threat of jellyfish, so shrimp don’t even rate a mention. This was clearly an oversight on my part; I’ve been learning lately about a few sorts of shrimp that are packing some deadly firepower. (They may be useful allies when the jellyfish come for us, let us all take note.)

Still from BBC's "Invisible World"

Still from BBC’s “Invisible World”

The Alpheidae are a family of shrimp commonly known as “snapping shrimp,” and the Pistol Shrimp is perhaps the family’s most famous member. It’s a tiny animal, only a few inches long, but it’s packing some serious firepower in the form of a claw with a specialized snapping mechanism that allows it to “shoot” a high-velocity air bubble through the water. That might not sound so intimidating, coming from a tiny shrimp, but trust me when I tell you it’s seriously bad-ass. The Pistol Shrimp’s claw has a jointed “hammer” mechanism which snaps shut with such force that it vaporizes the water in front of it, forming a bubble. The bubble doesn’t go far, only about 4 centimeters, but it travels at speeds up to 60 miles per hour, generating enough force to kill fish, break glass, and knock well-armored opponents on their proverbial asses. The bubble’s real power, though, is in its collapse; in a process known as cavitation, the bubble essentially implodes under the pressure of the water around it, and that implosion not only produces sonoluminescence — a short burst of light which in the Pistol Shrimp’s case is invisible to the human eye — but also generates temperatures nearly as hot as the surface of the sun. The Pistol Shrimp was the first animal that was ever demonstrated to produce sonoluminescence (in a future featured creature we’ll take a look at the Mantis Shrimp — not actually a shrimp — which packs a similar punch and has also been found to generate sonoluminescence).

Still from BBC's "Invisible World"

Still from BBC’s “Invisible World”

The noise of the Pistol Shrimp’s bubble collapsing is brief, less than a millisecond, but the sound produced can reach a staggering 218 decibels; when there are a lot of them in one place, the cacophony is loud enough to interfere with underwater communications and submarine sonar. (The voiceover narration on this video is completely terrible, but it gives you a great sense of exactly how noisy the ocean really is — skip to about 6:00 for some great audio — and snapping shrimp are a major contributor to the noise.)

The Pistol Shrimp uses its awesome firepower to stun, disable, or even outright kill its prey, which it usually hunts from the comfort of its own burrow; it detects passing meals with its antennae, stuns its meal with a bubble blast, and then drags it into the burrow to devour. Lazy bastard. It can also use its pistol-claw in self defense and to communicate with its fellow shrimp. Not quite cool enough for you? Okay, how about this: if a Pistol Shrimp’s gun-claw is torn off, not only will it grow a new limb to replace the missing one, its other claw — which is typically smaller, while its shooting arm is half the size of its body — will grow to become its new shooting hand. It can grow back missing parts and it’s ambidextrous. If you don’t seriously love this shrimp right now, I can only assume it’s because you’re jealous.

BBC Weird Nature

Some varieties of Pistol Shrimp have also learned to live cooperatively with another species, which is more than I can even say for me and my dog. Pistol Shrimp build their own burrows, but they’ve been known to share their space with goby fish, which have superior eyesight and act like watchdogs for the shrimp. The fish alerts the shrimp to danger, and then they both retreat into the burrow together. Presumably they also snuggle. I’m guessing the fish is the little spoon.

BBC Invisible Worlds

Featured Creature Friday: The Freeloading Alcon Blue Butterfly

Last week I featured another bizarre caterpillar, Hawaii’s carnivorous Eupithecia, and I thought perhaps this week you’d like to meet a larva that is somehow, impossibly, even more bad-ass.

Denmark’s beautiful Alcon Blue butterfly looks about like you’d expect, for a butterfly. It has lovely blue wings and eats flowers and is about as intimidating as a nice decoupage. But don’t let them fool you. These lepidoptera are devious little bastards.

You see Jimmy, when a mommy and daddy butterfly love each other very much, they put their abdominal regions together and get nasty. Don’t pretend you’re scandalized. I know you’re familiar with the mating habits of butterflies. I’ve seen your browser history, buddy.

For the most part, the Alcon Blue’s reproductive cycle looks pretty normal. They get it on, as butterflies do, and then the female lays her eggs on a specific flower that she’s terribly fond of, and then the larvae hatch and hang around eating plants for awhile, and then shit starts getting real. You see, when the larvae are large enough, they drop down to the ground and sit around waiting, while emitting a delicious pheromone-y perfume that makes them smell irresistible to ants. And I’m not talking irresistibly delicious, either.

The scent that the larva emits convinces the ants that the larva is one of their own offspring, and they’ll pick it up and carry it right into their own home. In fact, they are so freaking stoked about this larval caterpillar that they will protect and preserve it at the cost of their own offspring. They feed it, they keep it clean, they make it the happiest little larva in all the land, and they don’t even mind that these faux-ants they’re tending to are eating not only the food they bring in but also they’re devouring the ants’ own larvae, because hey, who needs their own offspring when they can use all their resources caring for the freaking bad seed, instead?

Did you want another cheeseburger, sweetie? How about some Cheesy Poofs? No, don’t get up, I’ll make some snacks for you and all of your friends! Oh, you want to eat my other children? Okay, honey, that sounds fine!

Although this may sound like basically the perfect life for a larva, wherein they are fed and cared for and presumably get to spend all of their time playing Call of Duty, their gambit is not without risks. For one, the ants who are being parasitized might just figure the whole thing out, as this BBC article explains:

By looking at the patterns of infection/resistance and the genetics of different populations, the team was able to describe how the separate chemistries of the butterflies and the ants co-evolve in what amounts to an ongoing “arms race” – giving each animal periods and locations of dominance in their relationship.

So essentially, the ants change their chemical scent to help them recognize the butterfly larvae, and the larvae change their scent to adjust to the new situation, and on and on forever and ever. But that isn’t the only risk the Alcon takes inside the ants’ brood. They’re also preyed upon by a wasp called Ichneumon eumerus. The wasp, upon discovering Alcon larvae within an ant nest, will spray a chemical concoction that causes the ants to become confused and attack one another. Then it will seriously screw up the Alcon’s life; to wit:

When the wasp detects an Alcon caterpillar inside an ant colony, it charges inside and sprays a pheromone cocktail that makes the ants attack each other. The wasp slips through the confusion, lays its eggs inside the caterpillar and leaves. After the caterpillar turns into a chrysalis, the eggs hatch and consume the it from the inside.

Pleasant, no? And this is all while the little beggars are still just little pink slug-looking things. If they survive the wasps long enough to actually pupate — which may take up to two years in the ants’ care, being total freeloaders — their chemical defenses no longer protect them from being seen by the ants as intruders. They then get to run the gauntlet out of the ants’ brood chamber and out into the world. They aren’t without defenses, however; they’re covered in loose scales which detach when grabbed by angry ants, allowing them to make their escape.

You might think that this sounds like a horribly convoluted way to reproduce, and frankly you’d be right; the Alcon Blue lives a very specific life which requires specific plants (they feed from and lay their eggs only on Marsh Gentians and Willow Gentians) and needs ant colonies (though it is somewhat non-specific in which ants will do) to perpetuate its life cycle. Both the butterflies and the wasps that prey on them are considered endangered, which is too bad because there are some scientists who would dearly like to leverage their brand of chemical warfare, but you’d probably think it was pretty good news if you were an ant; it probably gets tiresome being caught in the crossfire between butterfly and wasp.

Featured Creature Friday: Hawaii’s Carnivorous Caterpillars

Your childhood readings of The Very Hungry Caterpillar will do little to prepare you for today’s featured creature, because these particular caterpillars are not the cute, fuzzy, slow, living-bootbrush kind of creatures that you’re thinking of. These ones are quite rare specimens among caterpillars, even though their genus Eupithecia are found around the world, and they’re a terrific example of the stunning specificity of survival adaptions that occur on isolated islands. Because unlike their seed- and plant-eating cousins, these caterpillars eat meat.

Just imagine this slow-motion scene accompanied by the theme music from Jaws and you’re on the right track. OMG FLY THE SERIAL KILLER IS ABOUT TO GET YOU I TOLD YOU NOT TO GO INTO THE BASEMENT. (All photos on this post are stills from the BBC’s South Pacific, which is linked to below. Please buy it and support Benedict Cumberbatch’s documentary-narration career.)

The grappling inchworm chilling out in its FREAKING HANDCRAFTED SNIPER NEST.

These hunting Eupithecia — which have been given the excellent common name of “grappling inchworms” — have a pair of hair-like appendages on the abdomen which, when touched by prey like the common fruit fly, cause the inchworm to arch itself backwards, deploying its frankly bad-ass-looking grappling arms to grab the insect before it can escape. Then it eats it, because delicious, right? They also employ some pretty ingenious techniques — like the “looking like a stick” technique and the “just the edge of a leaf, nothing to see here” technique — to disguise themselves, so hapless prey won’t know what hit them until, well… it hits them. And even then they might not know, because they’re flies and if we’re honest, flies just don’t seem like the most well-read species to me.

Because Hawaii lacks many of the other forms of predatory insects that are found elsewhere, these inchworms apparently found a vacant ecological niche — and a very plentiful food source — and adapted to fill it. By being awesome. Less than 1% of the planet’s known 160,000-odd species of butterflies and moths eat other insects, and no other Eupithecia do outside of Hawaii.

The following absolutely gorgeous video from the absolutely fantastic BBC documentary series South Pacific is kind enough to offer you excellent video footage of this caterpillar in action, with the added bonus of narration by Benedict Cumberbatch:

(If the embedded video isn’t working for you, just click here.)

(On a side note, I can’t recommend this documentary series highly enough; it’s beautifully filmed, beautifully produced, beautifully narrated, and endlessly fascinating. You can purchase a copy from the BBC America shop, the BBC UK shop, or I would imagine from any major DVD retailer. You can also rent the discs on Netflix, though tragically as of this writing it isn’t available to stream.)

For more on these inchworms from someone who actually knows what they’re talking about, I’d like to highly recommend this blog post from the fantastic Bioblog.

Featured Creature Friday: The Plummeting Paradise Tree Snake

You guys. You guys, this is a snake. You guys, this is a snake THAT FLIES.

All my nightmares are coming to life.

I’ve always wondered exactly how skills like this develop in nature. I mean, I understand natural selection and adaptive evolution and all of that, but to me this looks like the sort of skill set that could only have come from a long line of severely depressed snakes. They were trying to end it all when they discovered that actually they can be kind of wing-shaped. Maybe they discovered a new purpose in life as accidental pilots and stuck around long enough to breed whole new generations of ridiculous flying snakes.

Or maybe they were just minding their own business, flying the old fashioned way on an airliner — perhaps on their way to a vacation destination far from their native southeast Asia — when Samuel L. Jackson started exterminating all of their friends, and they had to risk jumping just to survive the slaughter. (Now they’re just trying to get over the post-traumatic stress and are planning to bring a court case.)

Their gliding abilities are said to rival those of flying squirrels, and if you ask me they do the job with more style, too. And they come in some pretty swell colors, as you can see here. In addition to flying, they also have available to them a venom that’s powerful enough to paralyze the small lizards and mammals that they prey on but not really powerful enough to hurt humans badly, so at least we don’t have to worry about like… flying acid attacks or anything. They’re also pretty freaking cute. Just look at those adorable little nose-holes! Awww!

Paradise Tree Snake closeup

Featured Creature Friday: The Wonderful Woolly Bear Caterpillar

I’m not really an entomology sort of person. It’s partly because insects are often creepy and partly because I’m just not good enough at spotting them to foster an interest. It’s the same reason I’ll never take up birdwatching: when your eyesight is bad enough that it takes you five minutes to spot a full-grown eagle, it might be time to consider an interest in elephants, instead.

I am generally a fan of caterpillars, though. For one thing, they’re often incredibly cute in a bizarre and alien sort of way, and like the butterflies and moths they become, caterpillars come in a truly staggering array of colors and configurations. Some of them look like tiny cacti and some have horns and some are poisonous and some will burn you with acid and I’m sure that deep down, some of them just want to be loved.

But we’re here to talk about a particularly magnificent specimen in the form of the Woolly Bear Caterpillar, which is particularly extraordinary because it has considerably lengthened its lifespan through cunning use of cryogenic technology.

I've named this one "Fry." It was only trying to deliver a pizza...
photo by IronChris, by way of Wikimedia Commons and used here under Creative Commons license.

Compared to some other caterpillars, the Woolly Bear might not be much to look at — it’s sort of like a multicolored scrub brush — but it’s anything but mediocre. Where most species of caterpillar live only a few weeks, the Woolly Bear has adapted to cold climates by simply freezing solid when the temperature drops, which has extended this little Lepidoptera’s lifespan considerably. In warmer climates they’ll live a few years; in the arctic, their badassery extends to fourteen years or more. Every winter they freeze, every summer they thaw, eat, and grow bigger, until they finally become moths, live just long enough to reproduce, and then die. It’s a bit of an anti-climax, but who knows, maybe being a moth sucks.

As you all know, I’m a sucker for scientists getting all excited about nerdy things — they’re like teenage girls at a Bieber concert — so here’s a fantastic video from the new series Frozen Planet with a lovely gentleman and his lovely accent telling you all about the Woolly Bear and how completely awesome it is.

But wait, there’s more! Woolly Bear Caterpillars were also the first insects shown to self-medicate to stop parasitic infestation. Woolly Bears are plagued by a type of parasitic fly which is kind enough to leave a gift of larvae inside the poor caterpillar; when the little bastards hatch, they eat the caterpillar from the inside and then bust right out of there like they think they’re extras in Alien. But infected Woolly Bears can fight back by eating alkaloid-laden plants.

Bernays and her colleagues showed that infected woolly bears eat more toxic alkaloids than their non-infected peers. Healthy woolly bears also ingest alkaloids, but only in small amounts, apparently to make themselves unsavory to predators.

In addition, the team showed that parasite-free woolly bears that binge on alkaloids are more likely to die compared with woolly bears that take the drug in moderation.source National Geographic

So not only have they figured out how to treat their own medical problems in a totally groovy holistic fashion, but they’re also better at moderation with their alkaloids than I am with chocolate. Thanks a lot, Woolly Bear caterpillars. Now I feel like crap about myself. Which is probably how you’re going to feel when you finally turn from a bad-ass caterpillar into a completely boring moth. CHECKMATE.