Tarantism

I once had a housemate with a terrible fear of spiders. But she is also very kind-hearted, so instead of killing them, she’d trap them under a cup…and leave them outside of my door. Girl is lucky she’s so cute or she’d find more than a cardboard cutout of David Tennant in her bedclothes. Not that I dislike spiders, no, I was more concerned about tripping over surprise spider prisons. Actually I really like spiders; flies and mosquitoes drive me nuts so anything that eats them is a homie in my book. I even like these guys:

 

Goliath Bird-Eating Tarantula. They are the size of my face, wonder what they eat…Anyway, they’re hairy, scary beasts but there’s really no reason to run even from these guys (besides abject terror). Despite their size and overall creepitude, most tarantulas don’t pose much of a threat to anything larger than their dinner. Most can’t produce symptoms worse than a wasp sting or an intense burning sensation. Painful, yeah, but not lethal (unless you’re allergic).

So now you know! Tarantulas are just big cuddle-bugs!

Except don’t cuddle them, the hairs are strong irritants.

 

Source

Stewart, Amy. 2011. “Wicked Bugs”. Algonquin Books of Chapel Hill. Chapel Hill, NC.

 

PS. Tarantism was a kind of dancing mania in 1400-1600s Italy. Folks blamed it on spider bites but it was probably just moldy bread.

In Which I Argue with Hawaii

Sea pigs that squiggle and hagfish with no eyes, those naked mole rats and larvae from botflies, cranky rock crabs that crush my nerve endings, these are a few of my LEAST favorite things. Not the dog bites, not the bee stings, those bitches. OK, I hate those things mostly cause they intolerably ugly or intolerably UUUGH (botflies I’m looking right at you and don’t even pretend I’m not), call me petty, whatever. These things don’t scare me, though. They’re not dangerous, why would they? Venomous snakes and spiders are kind of scary, but venom is a hassle for them to produce so they try to warn you when you’re too close and making them nervous (see: rattlesnakes, spitting cobras, etc). Hell, brown recluse spiders and black widows will run before anything else. Large predators, sure, but pack some bear spray, travel in groups and I should be good to go. Sharks? Pssht, I barely sea kayak and have no interest in surfing so no shark is going to mistake me for a turtle snack anytime soon. You want to know what’s really scary? What would make me don a custom head-to-toe wetsuit if I went swimming in Australia? Box jellyfish. Goddamn box jellies. I can hear you Hawaiians out there (assuming I have Hawaiian readers…), “Man, what’s the deal? You get stung by a jelly, you get over it. Spray some ammonia on it and get back in the water.” I call bullshit, Hawaii. Box jellies are serious business. So what if it’s not a true jellyfish (scyphozoa) and belong to its own class (cubozoa). Even your Irukanji box jelly (Carukia barnesi) venom can cause difficulty in breathing, vomiting, coughing and also possibly death. Not to mention the excruciating pain, at the sting site, as well as the stomach, limbs, back and head. Put ammonia on THAT, Hawaii.

So why is a dumb jelly scarier than a snake that can spit venom at my eyes or a large cat that could rip my throat out with only a “playful’ swipe? You can prepare for that shit. Walk away from snakes you don’t know (and say “no”  if they offer you drugs) and if you think any big mammal is a danger, CARRY BEAR SPRAY. As a side note, I’ve been stalked by a tiger while working at a zoo. At least the tigers there thought that if they weren’t moving, you couldn’t see them. So I’d be walking to lunch past the back of the tiger exhibit and hear a sound, turn, and see a tiger frozen mid-step. Turn away, turn back, tiger had moved one more step. Maybe had tried hiding behind a rock the size of his head (but not the rest of his 350lb+ bulk). Not that Mushi would necessarily behave like that in the wild, BUT IT’S FUNNY. Also, bear spray does wonders. ANYWAY, that “dumb” jellyfish has eyes. Four small structures simply respond to light and accompany two real eyes; structures complete with lenses, corneas and retinas. It can see, process sights and hunt based on that. You may not look like dinner, but that “dumb” jelly does not care enough to avoid you. DOES NOT CARE. It can kill you just because it can’t be bothered to try and avoid you. This is a predator skilled enough to find its prey and deadly enough not to worry about predators of its own. It can also kill you when it’s dead. How about THAT, Hawaii?

ADDENDUM:Almost forgot to explain the box jellies mode of envenomation. Remember the nematocysts? Of course you do, I talked about them in Nudi Time ( https://dailyscienceblog.wordpress.com/2013/01/21/nudi-time/ ). Basically those are cells that hold contact-activated barbs on threads. It’s like a land mine, but instead of an explosion when you touch it, a poisoned grappling hook shoots out. Explosion of HORRENDOUS PAIN. Also the barbs regenerate after use. In most jellies the cells stop working after death, but box jellies are determinedly mean bastards so their nematocysts can still fire after they die. Happy swimming!

 

Source

Laidler, Keith. 2009. Animals: A Visual Guide to the Animal Kingdom. Quercus Publishing Plc, London.

Modern Dragons

Last night, in honor of my dad’s birthday and the 3 happy weeks he spent in high school reading Tolkien (and not doing much else), we went to the Imax to see The Hobbit. Despite seeing all of one foot, nostril and eye, Smaug stole the show for me. Though those shaggy ponies were a close second and I disapprove of excessive burninating, I have a soft spot in my heart for all things scaly. Especially if they’re dragons. Dragons dragons dragons. This is probably why snakes and the less derpy lizards hold such a fascination for me. Some kids had imaginary friends in grade school, I had an imaginary King Cobra named Spike.

Fast forward to undergraduate senior thesis and I discovered that the awesomeness of the ophidians was not limited to their stupidly vast variety of species. They, dare I say it, have some bitchin’ chemical compounds at their disposal. I am of course referring to snake venom, though as I pointed out in my previous post (https://dailyscienceblog.wordpress.com/2013/01/19/eau-de-my-thesis/), pheromones have a lot to bring to the table as well. Lord knows what kind of table, but if there are snakes involved, I am THERE.

It is easy to write off venom from any animal, be it snake, scorpion or platypus, as death and/or pain juice. Nasty stuff, sure, but venom produced by a given animal is specific to that animal’s needs. To clarify, venom is injected via bite or sting while poison is consumed. Both contain harmful chemicals, toxins. Venom components are largely proteins that perform a variety of functions, including immobilization, rapid death, necrosis, tracking and defense. Let me stop you before you look up necrosis and scar yourself for life: necrotizing venom rots tissue and assists in the “pre-digestion” of prey. Spiders like it, pit vipers like it, we DON’T. But it’s a great/gross example of how certain components have overlapping functions in the same or different species; necrotoxins assist in pre-digestion for brown recluse spiders, and provide powerful defensive bite; vampire bats need an anti-coagulant (chemical that prevents blood-clotting) in order to feed, but certain snakes use a heavier dose in their venom to provoke rapid death by hemorrhage; and immobilizing neurotoxins may merely hinder (allowing other toxins or offensive means to kill), or immobilize to the point of respiratory failure as occurs from TTX (pufferfish) venom. Toxins involved in defensive envenomation run the gamut and results range from the mild stings of bees and platypi, to the bullet-like stab of the tarantula hawk wasp to the lethal bites of black widows and mambas. This is because, except for perhaps the non-predatorial bees and the playpi, defensive stings and bites are not specialized and use the same toxins as those used in prey capture. Makes sense, right? Tracking components, which allow snakes to retrieve prey released following envenomation and avoid injuries sustained from tackling their dinner, are the only truly specialized part of venom.

Now that I have everyone thinking of how venomous snakes and assorted creepy crawlies can kill you, here are some numbers to drive home the point: in the world there are an upwards of 100,000 known venomous species (that include insects, arachnids, jellies, anenomes, snails, fish, reptiles, fleas and ticks), those species together possess an arsenal of over 20,000,000 toxins, of those 10,000 are known to science and 1,000 of those are studied in depth. Before you succumb to the warm fuzzies (or seizures of terror), I have a few more numbers. Those thousand toxins studied have provided us with over a dozen diagnostic tools and 20 drugs, some of which use toxin dosages that dance a fine Conga line between useless and deadly. Consider: Russel’s viper can kill you, but a derivative of its venom is used to measure clotting time in lupus patients; type 2 diabetics can thank the gila monster for their toxin that stimulates insulin production in the pancreas; viper venom anticoagulants have been around since the late sixties; and Brazilian pit vipers spawned the ACE inhibitor class of drugs used in battling hypertension. Much more is in the works, such as the cancer cell tag derived from deathstalker scorpions that could cut down the size of detectable tumors from a billion cells to a couple hundred. Effectively researched, the medicinal possibilities are endless. So they may not spew fire or fly, but snakes (and their less dragon-like, venomous compatriots) hold some downright mystical proteins in their jaws.

See? Black mamba is smiling, he just wants to say hi.

 

Source

Kardong, K. V. 2002. Colubrid Snakes and Duvernoy’s “Venom” Glands. Journal of Toxicology. 21.1 & 2: 1-19.

Holland, Jennifer S. Feb 2013. “The Bite that Heals”. National Geographic. 223: 64-83.

Photo credits me, komodo dragon credit Woodland Park Zoo, black mamba credit Monroe Reptile Zoo.