Monthly Archives: September 2008

Golden Dart Frog

We all remember the classic children’s fable in which a princess kisses a Golden Dart Frog and, while she waits for it to transform into a handsome prince, her heart begins to flutter, and eventually she realizes it’s not a good flutter at all but really a very serious ventricular fibrillation induced by a potent neuro/cardio toxin. Then she immediately falls over, dead.

The moral of the story, of course, is that you should never ever touch – let alone make out with – an extremely poisonous amphibian. Especially the Golden Dart Frog (Phyllobates terribilis, Lit. ‘A terribly embarrassing death by frog’). It’s estimated that of the 150-175 known species of dart frogs indigenous to Central and South America, all of which are poisonous to varying degrees, the Golden Dart Frog of Columbia is far and away the most lethal. It is, by many accounts, the most toxic animal on this planet and single-handedly accounts for Columbia’s shamefully high PMR (Princess Mortality Rate).

‘Can I turn into a handsome prince? Maybe I can, maybe I can’t. Why don’t you come over here and kiss me and we’ll find out together.’

If the scientific name P. terribilis and the fact that it’s an evil yellow frog aren’t enough to deter oral contact, then perhaps some sobering biochemistry will. When disturbed, the Golden Dart Frog secretes a ghastly powerful alkaloid batrachotoxin – from glands on its back and behind its ears – with the chemical formula C32 H42N2O6 and a molecular mass of 538.67 g mol -1.

But no need to concern yourself with the technical stuff. All you really need to know is that this organic molecule acts specifically on voltage-gated sodium channels by increasing the permeability of sodium cations, which in turn irreversibly depolarizes the cell membranes that the Na+ channels serve, effectively blocking neuromuscular transmissions1, which is an obvious problem when it comes time to oh, say, live and breath and the like. Indeed, the entire mechanism is remarkably simple:

See there? You learn something new every day.

In short, if the frog’s alkaloid batrachotoxin finds its way into an animal’s bloodstream (via a miniscule cut on your hands, for instance) it will completely shut down the peripheral nervous system and lead to cardiac arrest. One frog carries enough toxin to kill 100 people, so obviously, it doesn’t take much to kill one. You could probably hide a lethal dose of the Golden Dart Frog’s poison under a couple grains of sand2. Stated in less engaging scientific terms, a mere 136 micrograms in the bloodstream will kill someone who weighs 150 pounds. If you want to kill someone who weighs 96 pounds or 223 pounds or some non-multiple/divisor of 150, or a European who reports their weight in kilograms, you’ll have to set up the stoichiometric equations yourself.3

Dart frogs are so named because Amerindians in Central and South America’s rainforests are famous for using their toxins on the tips of blow darts. They catch the frog, hassle it, and then proceed to rub their darts all over the frog’s backside (by this time just absolutely glistening with death). Thus armed, they head out into the jungle, load the blowpipe, and recite the warrior’s creed of, ‘Dude. Seriously. Be really, really careful where you point that thing.’ (This is a good time to remind Animal Review readers that one should never eat a monkey dispatched by a Columbian Amerindian. It’s supposedly safe to digest the Golden Dart Frog’s toxin after it’s been cycled through an animal, but better to be safe than sorry. Stick with the plantains.)

By now you’ve most likely heard enough and, if you’re like most people, you definitely want a Golden Dart Frog for the terrarium in your living room. Sadly, this is dumb but doable. Dart frogs raised in captivity do not produce the alkaloid batrachotoxin, because this ability is entirely diet dependent. It was recently discovered that the Golden Dart Frog feeds on a beetle that gorges itself on poisonous plants. The beetle accumulates the toxin and posthumously passes it up the food chain to the dart frog. If denied these insects, Golden Dart Frogs will eventually lose their toxicity. But this process may take years, so the wild-harvested Golden Dart Frog is recommended only for that special kind of weirdo hobbyist who doesn’t mind a very real risk of killing the cat, the maid, the neighbors, the neighbors’ kids, his or her kids, his or her frog-curious friends and loving parents, the landlord, the cable guy, the phone guy, the TV repairman and/or him/herself.

‘Do I still secrete a deadly neuro/cardio toxin? Maybe I do, maybe I don’t. Why don’t you try cleaning this terrarium and we’ll find out together.’

Be that as it may, the innocuous-looking-but-deadly Golden Dart Frog is headed towards an excellent mark. Animal Review is more than willing to award a grade of A to any animal that can instantly kill whatever eats/kisses/touches it, out of awe of Mother Nature (and also fear). However, there is a snake called Liophis epinephelus that has somehow developed immunity to the Golden Dart Frog’s poisonous wares, and so the Golden Dart Frog is regularly reminded that DNA mutation is a double-edged sword.

GRADE: A-

1 Discussion question: Sodium ion channels are also present in the nerve and muscle cells of the Golden Dart Frog. So why does it not succumb to its own toxin? (The answer is upside down at the bottom of this page. Nah, we’re just messing with you. The frog evolved sodium ion channels that aren’t affected by the alkaloid batrachotoxin.)

2 But that would be weird.

3 It is beyond boring. We don’t want to know about it. Just keep your units straight and that’s all we have to say on the matter.

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The Lobster

Consider the lobster1 (Family Nephropidae, aka ‘$9.99 All-You-Can-Eat’). The term ‘lobster’ includes well over 30-odd species2 of marine crustaceans, all of which have a chiton3 exoskeleton, two pincer claws, five pairs of jointed legs, and like nineteen different recipes.4 And that latter fact is, in a lobster shell, the reason why it’s not such a great deal to be a lobster these days.

Did we all do something or something?

By far the most popular lobster recipes are the ones that involve boiling a lobster alive, and that’s where things really go downhill for the vast majorities of lobsters who take a wrong turn into a lobster trap that was baited with delicious dead herring.5 There are other preparation methods, but boiling alive almost always wins out because it’s about as simple as boiling a pot of water (and then tossing a large crustacean into it) and maximizes the freshness of the meat.6 Moreover, boiling has the added benefit of turning the lobster’s shell bright red from of its natural muck-brown/algae-green hue, which doesn’t seem nearly as appetizing next to liquid butter.

A large amount of thought and argument has already gone into the question of whether lobsters feel pain6, but it seems pretty definite that, at the very least, lobsters don’t want to be boiled alive, since they will attempt to cling to the sides of the container from which they’re being dumped into boiling water, and then will make every effort to get out of the boiling water once in it. So let’s assume that, at the very least, lobsters can’t be particularly jazzed about how humankind has decided to consume them.

This, then, is the great irony of the lobster’s modern existence. For all the technological improvements and conveniences enjoyed by today’s working lobster, it still stands a pretty solid chance of meeting the decidedly unmodern fate of being boiled alive. Thus, the lobster is a crawling, benthic reminder that Fate is a cruel and capricious mistress, because, from any kind of objective standpoint, nobody would ever want to eat a lobster, let alone consider it a luxury. Lobsters are, essentially, giant bugs. They have long, bug-like antennae to find their way around; they have numerous jointed legs; and they live on the muck and the mire of the ocean floor, eating their fair share of detritus. And they are, in fact, members of Phylum Arthropoda, which includes crustaceans (lobsters et al), spiders, millipedes and centipedes, and insects. Indeed, the harder it’s considered, the decision that of all the creatures that live in the sea this is the one to boil alive and dunk in a tank of butter really stops making a lot of aesthetic sense. It is safe to say that if aliens from another galaxy came to Earth, their second question (right after ‘Which way is the bathroom?’) would quite probably be to ask, ‘Why are you eating giant insects?’

‘You humans eat what again?’

And this bizarre reality is, in fact, a modern twist. Until recent times, lobsters were considered low-class fare, partially because they are, quite literally, bottom feeders. Well into the nineteenth century, lobster was the food of the poor. Indeed, some American colonies had laws against feeding inmates lobster more than once a week, as more often than that was considered inhumane.

This man was later released on a technicality for being given too much surf ‘n turf.

But not so now. Fate has turned its back on animals that can not only grow past three feet in length and nearly 50 pounds in weight, but also may live more than 100 years because of their “negligible senescence,”8 and turned them into innumerable mayonnaise-based dishes.

Mmmmmm….insecty.

Fate then really put the screws to the lobster, by turning them bright red in boiling water, which suppresses every pigment in their exoskeleton but one (the red one). Now, were it that the boiling suppressed every pigment but lime green, nobody sane would pair that with a steak. And the lobster’s one moment of sweet revenge – the fact that eating a lobster is a bit of a nightmare of juices and oils and strange hammering tools from which neither skin nor clothes soon recover – comes far too late for the lobster to appreciate.9

Grading a lobster is problematic, because it requires consideration not just of both their inherent qualities, but also the giant lobster in the room: they taste good. And potentially more problematic is the fact that in order to enjoy them we usually resort to tossing them in boiling water. These bundles of issues, in turn, raise more issues (for instance: ‘Would a high grade encourage more people to go out and buy a lobster to boil alive at home?’, and if it did, does that make Animal Review culpable in the lobster’s death, not to mention the reader’s potential moral collapse?). Giving it serious thought becomes almost mind-numbing, and so Animal Review has decided to punt, and to pick a grade from a hat.

Thankfully, it’s a moderately ambiguous one.

LOBSTER GRADE: B

DFW GRADE: A+ 🙂

1Lest there be any confusion, yes, this is plagiarized.

2This does not include spiny lobsters, which lack claws and are whence lobster tail comes. Spiny lobsters consist of about 45 species within family Palinuridae (lit. ‘succulent’).

3Chitin comes up fairly regularly in discussing animals, here goes: chitin is a long-chain polysaccharide polymer made up of subunits with covalent β-1,4 bonds, about which bonds it is important to know that this type of bond is found between the glucose monomers in cellulose (crucial to leaves and bark and wood and other relatively hard aspects of Kingdom Plantae), and it is the bonds that give the overall rigidity to the polymer. The rub is that crustaceans have to molt their exoskeleton (which they then eat) every so often as they outgrow it, and between the time they get rid of their exoskeleton and grow a new one, they’re particularly vulnerable to predators, as well as the embarrassment of everyone seeing them nude. Oh, and someone might boil them.

4Just a guess. It’s likely far more than that, and probably right now some student is powering his or her way through cooking school by figuring out how to make lobster quiche. Wait…a Google search has determined that there is out there such a thing already. That student will probably not do as well as he or she was planning. Dude, try lobster pizza. Wait…yeah nevermind. Man, we really undershot it with the nineteen recipes. Maybe more like 1,900 recipes. And try lobster schnitzelnothing.

5Like you haven’t.

6Some chefs will stab the lobster in more or less the forehead area prior to putting them in the boiling water, but since the lobster has numerous ganglia (nerve bundles) and not a straight-up brain, that might not actually be much help in the pain-negation department.

7Stop what you’re doing right now & cf. www.gourmet.com/magazine/2000s/2004/08/consider_the_lobster You will be much better and happier for it.

8Little or no cellular aging.

9After they’ve been boiled.

*UPDATE* – Not cool, Science

News this morning that hundreds of new animals species have been found on Australian reefs, including brilliant soft corals and tiny crustaceans, provides further ample evidence (like any was needed) that Science simply refuses to get its collective act together.

This is not okay.

Yet again, Science has created more trouble for everyone by finding more inconsequential species about which nobody will ever need to know.

Scientists the world over owe the world an apology, as well as a promise to get back to the important work of keeping tabs on Great White Sharks.

Anaconda

Anacondas (Genus Eunectes, lit. ‘Need that crushed?’) comprise three species of massive non-poisonous crushing snakes inhabiting wetlands in South America. Of these, the green anaconda is the largest and is widely accepted as the world’s largest snake, often growing to twenty feet in length and several hundred pounds (in weight), allowing it to suffocate its prey via powerful crushing muscles. After crushing – or simultaneously drowning – an animal, the anaconda swallows1 it whole, and waits for up to a month for it to digest, much to the horror of everyone else at the restaurant.

A cappuccino would really help here. Maybe a nice grappa. Actually maybe I’ll just have both. And can I see a dessert menu?

It is unclear how large an anaconda may grow to be, but rumors of 40 foot anacondas roaming the wetlands in search of small children to crush have been used for centuries to scare – you guessed it – small children. Though there seems to be scant proof of anacondas eating human beings, it’s also probably happened, and, quite honestly, we should stop living in denial about it.

When placed in captivity, anacondas are extremely aggressive, and their poor attitude is often attributed to childhood crushing they suffered at the hands of alcoholic parents. It may also have something to do with being locked in cages for people to stare at.

If you dudes make me live in a zoo I’m gonna be wicked annoyed.

Anacondas can be frequently observed crushing the life out of a variety of animals, including capybaras, adult white tailed deer, fully-grown spectacled caimans, jaguars, JaguarsTM, elephants, washer-drier combos, and unicorns.2

The anaconda’s beverage of choice.

Anacondas are generally solitary crushers until it’s time to find a mate. And when that time rolls around, a male anaconda will invite his anaconda girlfriend to move into his apartment, but then he’ll regret it pretty soon when the lady anaconda starts redecorating and talking about getting married, and eventually, after the lady anaconda is gravid3 (pregnant), she may well crush her boyfriend and eat him.

The observation of female-to-male carnivorousness among anacondas is well-documented, though its causes remain poorly understood (because they were crushed). Some speculate that it is due to the marked sexual dimorphism in anacondas, with females being much larger than males. Still others suspect males present an easy meal for a pregnant female. Another theory is that sometimes a girl just feels like crushing her man and eating him.

I’m not a player, I just crush a lot.

Here’s something: oftentimes many male anacondas will attempt to copulate with the same female, resulting in massive ‘breeding balls’ of up to twelve males wrapped around a single female. If you ever see a breeding ball, shoot it with a gun.

Anacondas are ovoviviparous, meaning that eggs hatch inside the mother’s body and result in live births, and a baby anaconda is born with enough crushing power to kill a medium-sized dog.

In conclusion: carpe diem. Seize the day. And then crush the life out of it.

GRADE: A

1Contrary to what you heard on every single field trip to the zoo, snakes do not dislocate their jaw to swallow their prey. They simply have extremely flexible ligaments on their jaws, which allows them to fit stuff in their mouth. And since they lack sternums, the only limit to what they can get in their stomach is their imaginations.

2Crushing the mythical horse, they swallow it whole, and later burp up the horn.

3The term ‘gravid’ refers to a pregnant fish or snake that bears live young, and in entomology it describes a pregnant female insect. The point is, it’s quite an insult, so hold on to that one.

Bats

In a perfect world, the only mammal allowed to fly would be baby polar bears, and they’d occasionally land on you to give you a hug. And you’d say, “Hey get off me, crazy baby polar bear, I’m late for work!” But you’d be giggling the whole time and the baby polar bear would know you weren’t in the least bit serious about it getting off you. And as soon as the baby polar bear grew large enough to kill (~26 days), it would lose its ability to fly and go live in a zoo.

Sadly, that’s not the case. Yet another strike against Nature. Instead, we’re left with this:

‘I carry rabies, SARS and a copy of the complete works of Edgar Allen Poe.’

And so, bats (Order Chiroptera, Family Heebie, Genus Jeebies) are the only mammals that can fly1. The some odd 1,100 different species of bats can be divided into two main groups – or suborders – called Megachiroptera (megabats) and Microchiroptera (microbats). But while you might think that megabats are larger and microbats smaller, the categories actually have nothing to do with size, a fact that has driven many an etymologist over the thin edge of the cave of insanity.

While megabats generally eat fruit and fly by sight (easy), most microbats feed on insects. A few enjoy the blood of small mammals (their hematophagy is mentioned here solely to placate the etymology crowd). Microbats largely hunt at night using an incredibly sophisticated natural GPS system called echolocation. It’s a lot like active sonar in that the bat emits a series of ultrasonic ‘pings’ from its throat and then processes the returning echoes to construct a highly-detailed mental map of the landscape and its unfortunate prey. It’s different from sonar in that instead of being a clean backlit computer panel manned by officers in smart military uniforms, it’s organic and manned by a dreadful, flying, blood-thirsty mammal running the equations in real-time.

‘Scream all you want. It only gives me a perfect 3D map of your mouth.’

So now, it is at least clear that whoever coined the phrase ‘blind as a bat’ was as misguided as a rock. The bat’s echolocation is so disturbingly accurate, it can “see” the beating wings of a moth in absolute darkness and even catch the insect mid-flight. And here we thought it was cool when the Dark Knight inexplicably linked all the mobile phones to make a virtual image of Gotham City. Well, truth is stranger than fiction, and it’s also rarely two and a half hours long.

Given all this awesomeness (the flying in total darkness, the echolocation, the flying, the hanging upside down, the periodic forays into vampiredom, the flying), one can be forgiven for thinking the bat a natural choice for a nocturnal, stygian superhero. Dig a little deeper, however, and one has to wonder if Batman properly vetted the bat before settling on an ‘overall concept.’ In communicable disease circles, bats are known as vectors for a wide range of nasty pathogens. They are responsible for the large majority of human rabies cases. They carry SARS and maybe even Ebola. And their copious poop (known as guano2) tends to cultivate a fungus that can lead to a respiratory illness in humans called histoplasmosis. This may explain why the third Robin died from acute histoplasmosis in a five-part graphic novel entitled ‘An Awkward Death in the Family.’

Guano. The least exciting part of Alfred’s job.

But even allowing for their habits of carrying disease, hanging upside down in damp caves, and flying around at night using sonar to find sources of blood, bats do give something back to their community. They eat a lot of bugs, which is always appreciated. Not as exciting as dangling villains from rooftops, but one could argue it’s equally important. Also, many species pollinate plants. Furthermore, they are instrumental in distributing the seeds of plants, albeit via indiscriminate pooping. But come on, this is pro bono work here. Also, they’re said to be not altogether untasty, though the wings are a bit tough.

And so, with the bat, there is good and bad, positive and potentially severe negatives, upsides and upside downsides – such is the nature of Batman.

GRADE: C+

1 There are some mammals, such as the ‘flying squirrel’ that can glide. There is also a mammal that can build large machines in which to fly. To be precise, the bat is the only mammal that enjoys powered flight without having to go through Dallas-Fort Worth.

2 Bat guano is highly valued as a fertilizer. So much so that the American Congress passed a hilarious little piece of legislation back in 1856 called the Guano Islands Act. It essentially allows American citizens to seize any island that contains guano deposits, so long as that island isn’t controlled by another government. So next time you’re vacationing on a deserted tropical island and you see a pile of bat poop, you may legally claim that island as a U.S. possession. That’s nice to know, right? For the benefit of Animal Review readers who may be questioning this assertion (and for good reason), here’s the exact legislation as copied from the online U.S. code collection of Cornell University Law School:

§ 1411. Guano districts; claim by United States

Whenever any citizen of the United States discovers a deposit of guano on any island, rock, or key, not within the lawful jurisdiction of any other government, and not occupied by the citizens of any other government, and takes peaceable possession thereof, and occupies the same, such island, rock, or key may, at the discretion of the President, be considered as appertaining to the United States.

There you have it. You’re in the clear. Go nuts.

Sea star

Sea stars are invertebrates of Phylum Echinodermata (lit. trans. ‘Echino-skin-a’), comprising roughly 1,800 and many more rising stars that have yet to be discovered by Science’s talent scouts. They are also known as star fish, though using that term became a bit awkward after someone pointed out that they’re not fish.

Who was calling this a fish again? You’re fired.

Physically, most sea stars have five tapered appendages pointing out from a center mass, and thus do, in fact, resemble stars. This fact gives sea stars sufficient cover to adopt one of the most self-congratulatory names of any animal, terrestrial or marine.

Didn’t you see my name? Q.E.D., dude.

Sea stars are noted for their two stomachs, one for digestion and one for engulfing and digesting food outside the body, giving the sea star a disgusting something in common with their echinoderm brother, the sea cucumber. Sea stars also feature a ringed water vascular system, which is used for food and waste transportation, respiration, locomotion, and innumerable mind-bendingly boring freshman bio lectures. The water vascular system also provides the hydraulic force for the sea star’s tube feet, which resemble tiny suction cups and are used to eat and move about as slowly as you can possibly imagine.

Whereas most animals (humans included) are bilaterally symmetrical, sea stars are one of a special group of those who exhibit radial symmetry. In other words, they do not have left or right sides, but simply a top and bottom. So enjoy making conversation at the sea floor office party.

Why are you staring at my shoulder?

Perhaps you have heard that sea stars can regenerate lost appendages. So have we. So has everyone. Perhaps you have also heard that Coca-Cola used to have cocaine in it. And Eskimos have a hundred words for snow. Way to go.1 What’s important is that before this Lazarus-like ability of sea stars was understood, fishermen doubled their problems when, in an attempt to get rid of sea stars (who competed unfairly for the same prey), they cut them in half and, disgusted by what they had done, tossed them back into the ocean, only to find themselves facing twice as many now-angry sea stars later on.

Let’s toss all these starfish parts overboard and make a space to lay out. Good idea, right?

In addition to being able to regenerate lost body parts and bore high schoolers, sea stars also have the ability to be a keystone species. In the North American Pacific coastline, sea stars eat mussels, keeping their population in check and preventing the mussels from crowding out other species. This serves to protect biodiversity and reminds us that everyone, no matter how small, has an important role to play. And Eskimos have a ton of words for snow.

GRADE: B-

1 According to linguist Steven Pinker in his book The Language Instinct, the stuff about the Eskimo and the words for snow really isn’t true at all. Generously speaking, he comes up with no more than a dozen. But the Coca-Cola thing with the cocaine is true. But keep in mind, back when Coca-Cola was invented, you could buy cocaine from policemen to treat hangovers.

*UPDATE* – Sloths

With our sole national holiday dedicated to resting upon us, it is important to recall that, for the sloth, every day is Labor Day.