Dr. Jesse, B.A.

Author: Jesse Davidson

A 'nose leaf' is a term that just entered my vocabulary last week reading The New York Times science section. I figured it was a euphemism for the remnants of sloppy nose-blowing, or for the autumn golds and reds that you find in your tissue when you have a bad cold.

A 'nose leaf' has nothing to do with snot or getting sick, though, and is actually a body part: it is the gnarly horn that rests at the end of bats' noses and gives them their ominous appearance. In the case of vampire bats, it allows them to direct their sonar signal towards any entrée that has a velvety pulse and a meaty, cutaneous topping.

Because they are blind, these flying creatures have to choose their prey completely through the sound of the hosts' breathing, their body heat, and their smell.

Blindness, however, is not the only adversity in the life of the vampire bat. They have to consistently escape the notice of their much larger hosts while they feed. Each meal could be their end, and they never get to enjoy their dinner. They also have do deal with playground put-downs like "bloodsucker," "devil-bird," and "filthy flying weasel."

To top it off, vampire bats have no fun in the sun. No kickball, no frisbee, no Quidditch. Bats colonize dark dwellings during the day, and do not emerge until nightfall. You would have to overcome all this adversity to be the success story that is the vampire bat, and in this way they are more like Rudys than Draculas. But the myth of vampires, where these bats derive their name and reputation, is actually rooted in medicine.

A disease known as porphyria cutanea tarda is an extremely rare blood disorder that results in the blistering of skin when it is exposed to sunlight. Before the advent of modern medicine, it is speculated that people with this disorder were associated with vampires, zombies and werewolves. In this disorder, the body can't put the heme in hemoglobin, but instead the components of the unfinished heme are deposited on the surface of the skin, where they readily react with sunlight. With sun exposure, the skin can turn purple and erode with ulcers; sufferers usually have to wear protective clothing or have to stay indoors. Their gum line can also shrink, making their teeth resemble fangs.

It would make some sense that the victims of this disease might be able replace the "heme" by taking down a smoothie of red blood cells, but the analogy to vampires stops there. The disease is not contagious either, and you do not get any of the perks of being a vampire, like living forever.

And holy water tastes just the same.

This Halloween, do not forget that the old costumes like vampires or werewolves are still fair game. They have a rich history in both media and medicine, and should not be completely tossed aside just because your little brother is being one. For the past four years I've been Rod Stewart, Joe Dirt, or some other mulleted icon, and my ideas are starting to run thin, so I might have to revert back to the these oldies. I'll probably just end up wearing a sheet with two eyeholes.

The myth of vampires may have more scientific fact than you may be comfortable with, but there is no need to worry about your neck this weekend. The worst that could happen is a hickey.