Cannibalism is popular. At least among animals like chickens, chimps, hamsters, lizards, spiders and rabbits (Et tu, Bunné?) They've all done a little dirty dining. And though it's largely fallen out of favor during the last 100 millennia or so in the human diet, we humans used to love a little person tartar. Science is just now figuring out the true nutritional value of eating you and frankly, you aren't worth the trouble.

Dr James Coal, an archeology lecturer at the University of Brighton has been calculating your nutritional value by pound for the last year (something he admits put him off bacon, briefly). He says the prehistoric practice of human consumption by other humans is a head scratcher, because from a sustenance point of view, it just doesn't make sense. "When you compare us to other animals, we're not very nutritional at all." Especially when you're trying to feed a tribe of say 30 peckish pre-historic people.

Popular paleolithic menu items like beavers and boars offer an impressive 1,800 calories per pound of muscle (that's like all your Weight Watchers points for the day). Comparatively, humans offer a pretty measly 650 calories per pound of flesh. A look at the graph below suggests that 60% muscle mass seems to be the sweet spot for nutritious consumption. So if prehistoric humans were going to eat a guy, they might make sure he was the equivalent of a gym bro. Size mattered. Stacked against other edible "meats", we're pretty scrawny. You'd need a bunch of people to feed a bunch of people. Or, like five prehistoric gym bros. It makes far more sense to hunt larger, slower, dumber creatures. Nutritionally. The point is, a woolly mammoth or rhino makes a much better buffet.

Still, ancient man ate a lot of ancient man. The question is why? Human meat really wouldn't be worth the effort of coordinating a hunting party. Unless someone was injured, old or ill, the return on investment wouldn't pass the sniff test. "Hey, have you noticed that Gorack's been sneezing a lot lately?" *licks lips* Still, one creepy cave site in Spain proves the practice was the norm, and probably wasn't for nourishment. Gran Dolina holds the slaughtered remains of eleven cannibalized kids and adolescents. Eeesh. The cutting and gnawing marks on the bones are tell-tale but motivation is still cloudy. It gets worse. Flesh and brain was on the menu, frequently. The remains were uncovered in archaeological layers spanning a hundred thousand years or so. So familial flesh was a regular occurrence for a while. Like Taco Tuesday. Sorry. But Cole suggests cannibalism served more of a social function and was likely ritualistic or related to tribal war, not hunger. Comparable to bringing a bottle of wine to a party or liking your boss's IG posts. It'd be rude not to. Cole's current creepy theory is we ate humans because we chose to, not because we had to. Anthropologist Silvia Bello of the Natural History Museum in London tends to agrees with him. She says "Paleolithic cannibalism was probably more often practiced as a 'choice' rather than mere 'necessity,'".

Thankfully, our culinary tastes have evolved over time and we currently make better "choices", leaving cannibalism to the bunnies.

Marc Beaulieu is a writer, producer and host of the live Q&A show guyQ LIVE @AskMen