When it comes to vampiric humanoids, we place far too much emphasis on viral infections and supernatural curses. Because at heart we have something far more fascinating: a humanoid sanguivore -- and an obligate sanguivore at that, which is to say an organism that depends on blood exclusively.
Physiology of the Vampire I want you to forget those sexy, goth blood drinkers and day-walking glitter vamps. The reality of a humanoid vampire would be far more monstrous -- and significantly less romantic.
This nocturnal creature comes for you in your sleep, just when you're most vulnerable. Stealth is its greatest attribute and your vital fluids are all it desires.
The vampire's body is emaciated to the point of starvation, for blood is hardly a font of necessary nutrients. Forget that old lie about "power in the blood," because it's just protein and water. There's no fat for the vampire to store away in its corpse-like body, nothing to sustain it for prolonged periods of activity or even non-activity.
It's the same with vampire bats of the natural world. Unlike their insect-and-fruit-eating kin, they can't hibernate or migrate for they lack the fat stores. Instead, they must feed every single night, lapping up 50 percent of their body weight in order to survive.
Feast of the Vampire The humanoid vampire leaps on your as you slumber. Oh you don't feel its bony body against your own, because it does everything in its power to avoid your arousal. It just licks your neck with its strange, grooved tongue -- then slices in with a specialized tooth.
It's not much of a wound. You don't even wake. Really, it should stop bleeding in a mere couple of minutes, except the Nosferatu's saliva, like that of the vampire bat's, is a complex cocktail of anticoagulants. You'll keep bleeding for hours.
And there's no sucking involved here. Like the vampire bat, our ghastly humanoid sanguivore uses the piston-like motion of its tongue to make blood to flow into its mouth. It trickles in along a pair of groves on the bottom of its tongue, through a special cleft in its bottom lip.
Do you feel wet all of a sudden? Well, that's because your vampric visitor began to urinate shortly after that first taste. So now an increasingly potent stream of blood urine washes over your legs, because like the vampire bat it must excrete all excess water weight as soon as possible -- to say nothing of waste toxicity.
Like the vampire bat, it lives in constant threat of dehydration. It must stick to moist climates, for it lives in a constant physiology-induced desert no matter how tropical its surroundings.
Evolution of the Vampire At last, the creature leaves you drained in your urine soaked bed. It's off to find other sleepers in the night. But if you wake the next morning, you'll likely ponder how such a creature came to be.
Indeed, how did vampire bats evolve from their insect-eating kin? The answer remains lost in the mists of prehistory, but scientists have a hypothesis or two.
Perhaps their first taste of blood came from communal grooming -- the delicious *pop* of a blood-gorged parasite between their jaws. Or did they adapt to depend on the ticks and fleas of large, prehistoric mammals, before finally cutting out the middle man and sinking in their teeth?
Another hypothesis suggests they dined at the gaping wounds of mega fauna, feasting on insects and wriggling larvae -- and occasionally the salty-sweet blood of the host.
So imagine some impossible prehistoric age. See the pale, naked humanoids scale the flanks of some mist-walking behemoth. See them leap and bite at the creature's blood-gorged ticks and fleas. Or see them swarm an insect-choked wound on this lumbering titan's back, gobbling up flesh worms and flies before finally drinking from that crimson pool themselves.
Ah, the romance...
So there you have it!If you want to read all about the evolution and physiology of vampire bats, I highly recommend "Dark Banquet: Blood and the Curious Lives of Blood-Feeding Creatures" by Bill Schutt.
Monster of the Week is a - you guessed it - regular look at the denizens is of our monster-haunted world. Sometimes we'll focus on the cultural aspects, but mostly we'll look at the possible science behind a creature of myth, movie or legend. Be sure to explore the Monster Gallery as well as the Monster Science video series.
Robert Lamb is a senior writer and podcaster at HowStuffWorks, where he co-hosts Stuff to Blow Your Mind with Julie Douglas. He has a love for monsters, an aversion to slugs and a hankering for electronic music.