The world's first known human cannibals ate each other to satisfy their nutritional needs, concludes a new study of the remains of cannibal feasts consumed about one million years ago.
The humans-as-food determination negates other possibilities, such as cannibalism for ritual's sake, or cannibalism due to starvation. In this oldest known case of humans eating humans, other food was available to the diners, but human flesh was just part of their meat mix.
"These practices were conducted by Homo antecessor, who inhabited Europe one million years ago," according to the research team, led by Eudald Carbonell.
Carbonell, a professor at the University of Rovira and Virgili, and his colleagues added that Homo antecessor was "the last common ancestor between the African lineage that gave rise to our species, Homo sapiens, and the lineage leading to the European Neanderthals of the Upper Pleistocene."
For the study, published in the latest issue of Current Anthropology, the anthropologists analyzed food remains, stone tools, and other finds associated with Homo antecessor at a cave site called Gran Dolina in the Sierra de Atapuerca near Burgos, Spain. An apparent refuse pile containing tools and meat bones from animals also included multiple butchered bones of Homo antecessor individuals.
"Cut marks, peeling, and percussion marks show that the corpses of these individuals were processed in keeping with the mimetic mode used with other mammal carcasses: skinning, defleshing, dismembering, evisceration, and periosteum (membrane that lines bones) and marrow extraction," according to the researchers.
They added that the butchery techniques identified at the site "show the primordial intention of obtaining meat and marrow and maximally exploiting nutrients. Once consumed, human and nonhuman remains were dumped, mixing them together with lithic tools."
The other bones belonged to animals such as ancient bears, wolves, foxes, mammoths, lynx and more.
The bones and many stone tools indicate this was a campsite. All human butchering took place inside the cave.
"Other small-sized animals were processed in the same way," the scientists wrote. "These data suggest that they (Homo antecessor) practiced gastronomic cannibalism."
To further support this belief, the researchers point out that the consumed individuals came from a variety of age groups, ranging from young children to young adults.
The living arrangement, choice of prey, hunting and butchering methods all suggest that Homo antecessor lived in cohesive groups that likely would have competed with other Homo antecessor groups.
"Necessarily, a level of behavioral complexity is present among these human groups," the anthropologists believe. "This complexity allows using the cannibalism in response to resources competition with other human groups."
Based on other findings, eating one's enemy for political and nutritional gain was also likely practiced by Neanderthals and early members of our own species, who also practiced cannibalism for other reasons, such as during rituals.
Biologist Steven Vogel at Duke University ruminated on cannibalism in his book Prime Mover: A Natural History of Muscle. Vogel calculated that we'd have to consume too many of our brethren for cannibalism to be a sustainable nutritional source in and of itself.
Instead, humans "muscled our way up the food chain," Vogel said, developing better hunting weapons and other tools to allow almost everything to be on our menus.