The skull of a four million year old hominid has similarities to that of modern humans

A skull of a fossil four million years old, described in 1995 as the oldest evidence of human evolution in South Africa, has shown similarities to ours, when It was scanned at high resolution.

The skull of the extinct Australopithecus genus was found in the lower deposits of the Jacovec Cave in the Sterkfontein Caves, about 40 km northwest of Johannesburg in South Africa. Dr. Amelie Beaudet of the School of Geography, Archeology and Environmental Studies of the University of the Witwatersrand and colleagues of the Sterkfontein team scanned the skull at the University of the United States. Evolutionary Studies Institute, based at the University of the Witwatersrand, in 2016 and applied advanced imaging techniques in "virtual paleontology" to deepen the anatomy of the skull. Their research was funded by the Center for Excellence in Paleoscience, the Claude Leon Foundation and the French Institute of South Africa and was published in the Journal of Human Evolution

"The Jacovec skull represents a unique opportunity to learn more about the biology and diversity of our ancestors and their loved ones and, ultimately, about their evolution," said Beaudet. "Unfortunately, the skull is very fragmentary and one can not say much about the identity and anatomy of the Jacovec specimen. "

Thanks to high-resolution scanning, the researchers were able to quantitatively and non-invasively explore the internal anatomy of the Jacovec specimen. and report of information until then unknown on the genus Australopithecus .

"Our study revealed that the skull of the specimen Jacovec and specimens Ausralopithecus of Ste rkfontein in general, it was thick and essentially composed of spongy bone, "says Beaudet. "This large part of the cancellous bone, also present in our own skull, may indicate that blood flow in the Australopithecus brain may be comparable to us, and / or that the brain plays an important role in changing brain protection. "

Comparing this skull to that of another extinct group of our family tree, Paranthropus, who was living in South Africa with early humans there are less than two million Years, their study revealed an intriguing and unexpected aspect of

"We also found that Paranthropus skull was relatively thin and composed mainly of compact bone, which is particularly interesting because it can suggest a different biology, "explains Beaudet. In the cradle of humanity, UNESCO World Heritage Site, South African paleontological sites have played a central role in the exploration of our origins. In particular, Sterkfontein Caves' site has been one of the most prolific fossil localities in Africa, with over 800 hominids representing 3 genera of hominids recovered since 1936, including the first adult Australopithecus, the 39; emblematic "Mrs Ples" and "Little Foot", the most complete skeleton of a still early hominid found

"Jacovec's skull illustrates the relevance of Sterkfontein's fossil specimens for our understanding of the Human evolution, "says Beaudet. "Imaging techniques open unique perspectives for revisiting the South African fossil bademblage."

Learn more:
Sterkfontein caves in South Africa produce two new hominid fossils

More information:
Amélie Beaudet et al. Variation in the thickness of the cranial vault and internal structural organization in the hominid skull StW 578 of Jacovec Cavern, South Africa, Journal of Human Evolution (2018). DOI: 10.1016 / j.jhevol.2018.04.004