Vampire Bats Are Even More Disgusting Than We Realized
Fictional vampires have been turning into bats since at least as far back as the Baital Pachisi, a Sanskrit story a thousand years old. That's pretty impressive, considering that there's no official scientific record of vampire bats until the 19th century, and vampire bats live exclusively in the Americas. We guess the idea of an animal hanging upside down and drinking blood was so obvious that if it didn't exist, we'd have to invent it.
The vampire bat that we eventually discovered isn't exactly the same as the mythical monster, of course. For starters, it doesn't suck blood out of you as though through a straw after poking holes in a vein. Instead, its teeth make an incision, likely while you're sleeping, and then it laps up the blood once it dribbles out and forms a pool. Since it normally bites furry or feathered animals, it first shaves the target area, using teeth other than its incisors.
The way one bat researcher who PBS interviewed describes it, "It actually would be like Dracula biting your big toe while you’re asleep. He wouldn’t be going for your jugular. It would be a little bit like a foot fetish, to be honest." We are all worse off for having read that simile, and it surely says a lot more about the researcher herself than it does about bats.
Speaking of fetishes, the vampire bat will pee on you while it feeds. The primary reason for this is to add insult to injury, so you can wake up feeling violated in yet another way. The other reason is that the bat might spend a full hour lapping up your blood, and while it feeds, it also processes the blood it's already eaten. It chucks out as much water and nitrogenous wastes as possible from the blood, so that it can fill itself up to the brim with blood protein instead of all that extra stuff in blood that it doesn't need.
That huge amount of blood it drinks in one sitting also leads to our final disgusting fact about the vampire bat.
A vampire bat needs to drink blood every day to survive. It's not able, however, to successfully feed on a new victim daily, and when it does feed, it takes in more blood than it can use in one day. Eventually, bats will probably figure out how to bottle the extra blood and sell it in a blood marketplace, but for now, this is how they solve the problem: A fully fed bat will vomit up some of its meal and then let hungry bats eat the blood vomit right out of its mouth.
Scientists refer to this as "reciprocal altruism" because while the donor bat gains nothing from the act, and it may never see the recipient bats again, it will receive a return from bat society at large the next time it's hungry and eats someone else's vomit. Then again, scientists also refer to the vomit as "blood honey," likening it to how bees too process and regurgitate food, so let's stop letting scientists name things. Scientists are all weirdos.
Top image: Acatenazzi/Wiki Commons