We large-brained humans have instincts, strengths and acquired skills that allowed us to eliminate competition and establish our position at the top of the food chain many eras ago. According to Discovery News, the way our ancestors eliminated competition about a million years ago was by eating each other. This had the added bonus of keeping us feeling full. It wasn’t that there weren’t other, non-human options around. In fact, “other food was available to the diners, but human flesh was just part of their meat mix,” Discovery’s Jennifer Viegas writes. (Meat mix!)

Anthropologists have been aware that cannibalism happened in the Stone Age (2,000,000–c. 3500 B.C.) and beyond, but theories have abounded as to why it happened. A new study conducted by the University of Rovira and Virgili in Tarragona, Spain, establishes that this era’s man-eating wasn’t for ritualistic purposes or because of starvation, but simply for nutrition and “in response to resources competition with other human groups.”

The culprits in question in the new study are Homo antecessor, who lived in what is now Europe about one million years ago. Homo antecessor is “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,” the study’s lead author, Eudald Carbonell, explains.

These ancestors mostly ate children and young adults, perhaps because they were easy targets and of lower rank. They slaughtered them inside caves using the same technique used on other animals. “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,” the researchers explain.

The practice doesn’t stop with the Homo antecessor, as other research has already established. “[E]ating 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,” Viegas says.

But Steven Vogel, a biologist at Duke University, reminds us that humans wouldn’t have gotten to where we are today by eating each other. It was our noggins––specifically our skills at creating “weapons and other tools”––that allowed us to “muscle our way up the food chain,” he told Viegas.

Thankfully, we’ve mentally developed so much in the past million years that cannibalism is only an option for the completely insane or the completely desperate, as Hannibal Lecter and the Donner party’s ill-fated migration to California in 1846 demonstrate.