Oldest Evidence of Cannibalism Identified Among Human Ancestors

Researchers from the Smithsonian’s National Museum of Natural History have identified the earliest known evidence of cannibalism among human ancestors. In a study published in Scientific Reports, paleoanthropologist Briana Pobiner and her team describe cut marks on a 1.45 million-year-old shin bone from a relative of Homo sapiens found in northern Kenya. The marks, resembling those made by stone tools, indicate that hominins were likely eating other hominins as early as 1.45 million years ago. The findings challenge previous assumptions and shed light on the dietary practices of human ancestors.

The oldest conclusive evidence of cannibalism among human ancestors has been identified by researchers from the Smithsonian’s National Museum of Natural History. In a study published in Scientific Reports, paleoanthropologist Briana Pobiner and her colleagues describe cut marks on a 1.45 million-year-old shin bone found in northern Kenya. The cut marks closely resemble those caused by stone tools, making this the oldest known instance of cannibalistic behavior with a high degree of certainty.

Pobiner initially came across the fossilized shin bone in the collections of the National Museums of Kenya’s Nairobi National Museum while investigating the hunting and eating patterns of prehistoric predators. Upon closer examination, she noticed marks on the bone’s surface that appeared to be evidence of butchery rather than predator bites.

To confirm whether the marks were indeed cut marks, Pobiner sent molds of the cuts to co-author Michael Pante of Colorado State University, who conducted a detailed analysis. Comparing the marks on the molds to a database of tooth, butchery, and trample marks created through controlled experiments, Pante positively identified nine of the 11 marks as matching the damage caused by stone tools. The remaining two marks were likely bite marks from a large feline predator, with a lion being the closest match.

While the cut marks alone do not provide definitive evidence that the individual who inflicted them consumed the leg, Pobiner suggests that it is the most plausible scenario. The location of the cut marks, where a calf muscle would have attached, and their consistent orientation indicate that a stone tool was likely used to remove flesh. Furthermore, the similarity of these marks to those found on animal fossils processed for consumption strengthens the case for nutritional consumption rather than ritualistic purposes.

Although the term “cannibalism” may come to mind, Pobiner clarifies that it cannot be definitively established in this case because cannibalism refers to the consumption of individuals from the same species. The fossilized shin bone belonged to a relative of Homo sapiens, but the exact species cannot be determined with the available information. The use of stone tools also does not narrow down which specific hominin species may have been responsible for the butchery.

The study also raises questions about the chronological order of events. The stone-tool cut marks do not overlap with the bite marks, making it difficult to determine whether a big cat scavenged the remains after the hominins removed most of the meat from the bone, or if the cat killed a hominin and was then driven away by other hominins before they claimed the kill.

Another fossil, a skull discovered in South Africa in 1976, has previously sparked debate as the earliest potential case of hominin cannibalism. However, uncertainties about its age and the interpretation of the marks on the skull make it difficult to draw definitive conclusions.

To further validate their findings, Pobiner expresses interest in reexamining the South African skull that allegedly exhibits similar cut marks. She emphasizes the importance of revisiting museum collections and involving a diverse community of scientists with different questions and techniques to expand our understanding of the past.

The research received funding from the Smithsonian, the Peter Buck Fund for Human Origins Research, and Colorado State University.