An analysis of markings found on a 1.4-million-year-old tibia suggests that they were created with stone tools, according to scientists from several research centers in the United States. The Smithsonian Institution reports that Briana Pobiner, a paleoanthropologist at the US National Museum of Natural History, discovered these markings while researching in the collections of the Nairobi National Museum in Kenya with the goal of determining what kind of predators may have preyed on ancient hominins.
To identify the cause of the markings, Pobiner created casts of the marks and sent them to a colleague at Colorado State University for analysis. From the impressions, Michael Pante, co-author of the research, created 3D models and compared them to a database of individual marks generated in controlled experiments.
The researchers note in a paper published in the journal Scientific Reports that they identified nine of the 11 marks as “clear matches to the type of damage inflicted by stone tools” during dismemberment. The other two marks, they explain, could have been caused by one of the three different types of saber-toothed cats that inhabited the area at the time.
Although the marks alone do not prove that the hominid was consumed by individuals of the same species, Pobiner explained that they were located in the area where the calf muscles connect to the bone, which is an optimal place to extract meat. In addition, all the marks have the same orientation and similar angles, which reinforces the idea that the hominid was processed for consumption.
According to the expert, this is the oldest known case of a hominid that was consumed by others. She stated that there are numerous examples of species within the human evolutionary tree that consumed each other to survive, but this fossil suggests that relatives of our species practiced cannibalism much earlier than previously thought.