A study by scientists from 17 institutions, including the Universities of New York and the Witwatersrand in South Africa, revealed that an ancestor of humans had the ability to walk upright, but also to climb like a monkey.
The finding, described in the scientific repository eLife, gives an account of the computerized assembly of the skeleton of a Australopithecus sediba, a hominid that would have lived about two million years ago.
Scientists believed that this human ancestor walked upright, as suggested by fossil remains found in 2008 northwest of Johannesburg, South Africa. However, new fossils found in 2015 in a fantastic state of preservation allowed scientists to make a computer model of what the skeleton would have looked like. Australopithecus sediba.
The computer model was created after scanning the bones of different fossils, including new vertebrae discovered in 2015. With these images it was possible to see that the spine of the Australopithecus sediba It had the same curvature that contemporary humans and other hominids have (known as lordosis), but also that the muscles of the trunk had the strength of apes, known for their ability to climb.
“Although the presence of lordosis and other characteristics of the spine represent clear adaptations when walking on two legs, there are other transversal characteristics oriented towards the upper part, which suggests a powerful musculature of the trunk, perhaps for arboreal behaviors”, said the professor Gabrielle Russo of Stony Brook University, one of the study’s authors.
The scientists conclude their study by noting that the Australopithecus sediba it must have been a transitional ancestor, showing that at some point in prehistory, human ancestors walked and climbed alike.