Previously uncovered fossils, with marks on bones that show signs of butchery, suggest that our Stone Age ancestors engaged in cannibalism. However, as new research uncovers, it was not for nutritional purposes. In fact, humans, as it turns out, are a terrible source of nutrients and calories.
“When you compare us to other animals, we’re not very nutritional at all,” says study author James Cole of the University of Brighton, who published his work in Scientific Reports.
Next to eating one mammoth, which could feed 25 hungry Neanderthals for a month, eating a human could barely provide that same crowd with a third of the needed calories for a day.
Cole focused his study on the calorie count of human flesh and its nutritional value as a possible explanation for prehistoric cannibalism. Despite the potential significance of his work, Cole admitted his research was hard to stomach.
“I found it quite difficult to eat bacon for the last year or so,” Cole admitted.
Since our ancestors were smarter than most other animals, hunting them down was also much harder, making them especially undesirable prey.
“You have to get together a hunting party and track these people, and then they aren’t just standing there waiting for you to stab them with a spear,” says Cole.
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Cole argues that ancient cannibalism was not for pragmatic, nutritional reasons; rather, it happened to fill some social or cultural need. For example, if someone had died, the others might have cannibalized him because it was an easy meal or food was scarce. Other instances where cannibalism may have occurred was after a period of violence, such as defending territory.
Another theory is that the bones served as an effective “keep out” sign to outsiders, but it’s difficult to confirm that by examining the fossils.
Some experts, like anthropologist Silvia Bello of the Natural History Museum in London, agree with Cole’s conclusions.
“I agree with [Cole] that Paleolithic cannibalism was probably more often practiced as a ‘choice’ rather than mere ‘necessity,’” Bello said. “I think, however, that to find the motivation of the choice is a very difficult matter.”
However, Cole admits that there were limitations to his analysis of human nutritional value, which was only based on modern humans. But the real takeaway from this study, Cole explained, is that our ancestors had more of a mix of reasons for cannibalism than previously thought.
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Danielle Tarasiuk is a multimedia journalist based in Los Angeles. Her work has been published on AllDay.com, Yahoo! Sports, KCET, and NPR-affiliate stations KPCC and KCRW. She’s a proud Sarah Lawrence College and USC Annenberg alumn.