Earlier this year, several sets of footprints were found in Tanzania in the shadow of the Oldoinyo Lengai volcano, a sacred site of the Massai tribe. After analysis, it was found that the footprints belonged to one of our earliest ancestors, Australopithecus afarensis, and were estimated to be over 3 million years old. Interestingly, the footprints have revealed potential new evidence about the social structures of this early predecessor of Homo sapiens.
The footprints total fourteen in all, and appear to have been made by at least four to five individuals. Marco Cherin, director of the school of paleoanthropology at the University of Perugia, states that he believes the particular range of sizes among the footprints implies that Australopithecus social groups were arranged similar to gorillas, with one male accompanying several females:
A tentative conclusion is that the group consisted of one male, two or three females, and one or two juveniles, which leads us to believe that the male – and therefore other males in the species – had more than one female mate.
Giorgio Manzi, director of this archaeological project in Tanzania, wrote in his team’s published findings that the surprising size of the assumedly-male footprints show that there still remains a good deal we don’t know about our early ancestor, Australopithecus:
Thus, our results support a nonlinear evolutionary trend in hominin body size and contrast with the idea that the emergence of the genus Homo and/or the first dispersal out of Africa was related to an abrupt increase in body size.
However groundbreaking this new research purports to be, it’s not without its critics. Some have accused the researchers of jumping to conclusions based solely on the size discrepancies among the different footprints.
Whether or not the implications about social structure pan out to be confirmed, this study and other developments this year are revealing more and more about Australopithecus and peeling away some of the mystery of human origins. Earlier this year, it was found that Lucy, the most famous Australopithecus specimen, was a tree dweller and likely died as a result of falling from her treetop perch. If this new research is confirmed, perhaps it was the case that she was pushed by a jealous rival member of her harem.