Monster of the Week: Jason Voorhees

Jason listens for the sounds of sex. New Line Cinema

You probably dismiss Jason Voorhees as just another rampaging psychopath, one with an intense desire to murder nymphomaniac teens. And indeed, the subject's propensity for pro-abstinence bludgeoning knows no bounds -- but were you aware of the science behind his Modus operandi?

Like other North American Slashers of his species, Jason preys on copulating teens because the act of mating provides an irresistible target. But it's not because the teens in question are naked, intertwined and preoccupied. Nope, it all comes down to the sound of their enthusiastic boning.

As a team of German researchers point out in their 2012 paper "Bats eavesdrop on the sound of copulating flies," the notion that sex leaves you vulnerable to predation is both old and largely unsupported. Sure, the idea sounds convincing, but even the wider natural world offers few examples of it.

But that's where the Germans comes in. The team studied houseflies in a cowshed near Marburg, Germany. Here, the flies rarely flew at night and instead crawled around on the ceiling. Often times, they didn't even move. When they copulated, however, that's when the bats soared in for the kill.

Normally, the flies are invisible to the bats since background noise prevents their echolocation. But the buzzing of kinky insect lovemaking provide a clear, sonic target. Between 5 and 26 percent of all copulating flies snuffed it this way!

And just to make sure that a fly-with-two-backs doesn't simply create a larger target for echolocation, the researchers performed another experiment. They mounted dead flies around the barn in tantalizing sex positions to see if the bats noticed the necromantic tableau. They did not. In fact, they only swooped in when the Germans played an audio recording of flies having sex -- which I believe is an early Einstürzende Neubauten album.

Will we see similar experiments study the murderous ways of Jason and his ilk? Let's hope so.

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.

About the Author: Robert Lamb spent his childhood reading books and staring into the woods — first in Newfoundland, Canada and then in rural Tennessee. There was also a long stretch in which he was terrified of alien abduction. He earned a degree in creative writing. He taught high school and then attended journalism school. He wrote for the smallest of small-town newspapers before finally becoming a full-time science writer and podcaster. He’s currently a senior writer at HowStuffWorks and has co-hosted the science podcast Stuff to Blow Your Mind since its inception in 2010. In his spare time, he enjoys traveling with his wife Bonnie, discussing dinosaurs with his son Bastian and crafting the occasional work of fiction.