A memorial to the Donner party in Truckee, CaliforniaRich Pedroncelli / AP

For most of us, it’s unthinkable: Human is never what’s for dinner. Sorry to burst any bubbles, but in this episode, we discover that not only is cannibalism widespread throughout the natural world, it’s also much more common among our own kind than we like to think. Spiders and sharks do it; so do both ancient and modern humans. So why it sometimes make sense to snack on your own species—and what are the downsides? From Hannibal Lecter to the Donner party, cannibals are now the subject of morbid fascination and disgust—but how did eating one another become such a taboo? Join us this episode for our Halloween special: the science and history of cannibalism!

According to the zoologist Bill Schutt, the author of Cannibalism: A Perfectly Natural History, until recently, “the party line was basically that if you saw cannibalism in nature it was because of a lack of nutrition or cramped captive conditions.” In the past three decades, however, scientists have come to realize that cannibalism is surprisingly common, and that it occurs for a variety of different reasons: Male spiders who become their consort’s dinner gain a reproductive advantage, Schutt explains, while sand tiger sharks take advantage of their spare siblings in utero to hone their hunting skills before they’re even born.

Fewer species eat members of their own kind as you move through the animal kingdom toward primates—but, according to the archaeologist James Cole, cannibalism seems to have been a reasonably regular part of early human behavior too. His question was: Why? Were ancient humans eating one another out of hunger, or for more complicated reasons that have to do with spiritual beliefs about the soul and the body? To find out, Cole determined how many calories a raw male would provide, and then compared that with the number of calories in early humans’ other dinner options, such as mammoth, boar, and deer. He reveals his findings on Gastropod, which include a macabre organ-by-organ guide to the human body—useful for anyone who’d like to try cannibalism but is worried about their weight.

Cannibalism became increasingly taboo in modern history, as mainstream religions have typically frowned on the practice, labeling it as barbarous and driving it almost to extinction—while simultaneously using the accusation of man-eating as justification for colonial exploitation. Questionable morality aside, there are good reasons to avoid eating members of our own species. One of the bizarre medical mysteries of modern times is kuru, a fatal neurodegenerative “laughing” disease that began killing large numbers of the Fore people in the 1960s. This episode, we talk with Shirley Lindenbaum, the anthropologist whose fieldwork, carried out in remote Papua New Guinea in her 20s, uncovered the cause of the disease in the cannibalistic Fore funerary rituals. Today, however, despite the risks and the taboo, one kind of cannibalism is having a resurgence among celebrities and natural-birth advocates alike: placentophagy. It may be endorsed by Kim Kardashian West, but is there any scientific evidence behind the trend? Answers to all this and much more in this week’s episode!


This post appears courtesy of Gastropod, a podcast co-hosted by Cynthia Graber and Nicola Twilley that looks at food through the lens of science and history.

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