||New footprints belonging to bipedal hominins discovered at Laetoli, Tanzania indicate the presence of a marked morphological variability in our ancestors living 3.6 million years ago. The finding opens new paths in the study of their social behaviour.
The study saw the participation of Jacopo Moggi-Cecchi, from the Department of Biology who has worked in a team lead by the School of Paleoanthropology of the University of Perugia, in collaboration with researchers from the universities of Dar es Salaam, Sapienza of Rome and Pisa. The results of the work have been published in the journal eLife (DOI: 10.7554/eLife.19568.001).
The research team has detected a new set of fossil footprints belonging to the species Australopithecus afarensis in the Laetoli area, Tanzania. This is the same area where in 1978 the paleoanthropologist Mary Leakey found similar tracks, dating back more than 3.6 million years and attributed to the same species, to which the famous Lucy also belongs. The new trail has been marked by two bipedal individuals moving on the same surface, in the same time frame, in the same direction and with similar speed to the three individuals documented in the 1970s by Leakey.“A further key point of the discovery, comments Jacopo Moggi-Cecchi, is that judging by the size of the footprints and the length of the stride one of the two individuals must have been remarkably bigger than the ones discovered so far and, in absolute terms, one of the biggest of the species Au. afarensis”.
In this species, therefore, males must have been a lot larger than females, one of which was, in fact, Lucy.
“Given the relationship that exists in Primates between degree of sexual dimorphism and type of social organisation, continues Moggi-Cecchi, we can hypothesise that the social structure of these ancestors of ours was like that of Gorillas, that is of the harem type, with one adult male and numerous females with offspring.”
The research is part of the scientific project "Study and valorisation of Plio-Pleistocene paleoanthropological sites in northern Tanzania (Olduvai and Laetoli" carried out under the auspices of the Italian Ministry of Foreign Affairs and International Cooperation (Italian archaeological, anthropological and ethnological missions abroad). Further information and images here.
New fossil footprints of 3.6 million year hominins
Found in Tanzania by a team that includes academic of the University of Florence
20 December 2016