5/11/2023 0 Comments Chimpanzee hand gripsThese bones were also attributed to Sahelanthropus because no other large primate was found at the site however, it is impossible to know if they belong to the same individual as the cranium. In addition to the cranium, nicknamed Toumaï, and fragments of jaws and teeth that have already been published, the locality of Toros-Menalla 266 (TM 266) yielded two ulnae (forearm bone) and a femur ( thigh bone). This cranium, and in particular the orientation and anterior position of the occipital foramen where the vertebral column is inserted, indicates a mode of locomotion on two legs, suggesting that it was capable of bipedalism. Its description dates back to 2001 when the Franco-Chadian Paleoanthropological Mission (MPFT) discovered the remains of several individuals at Toros-Menalla in the Djurab Desert (Chad), including a very well-preserved cranium. Published in Nature on August 24, 2022, this study reinforces the idea of bipedalism being acquired very early in our history, at a time still associated with the ability to move on four limbs in trees.Īt 7 million years old, Sahelanthropus tchadensis is considered the oldest representative species of humanity. A research team, involving researchers from the CNRS, the University of Poitiers and their Chadian partners, examined three limb bones from the oldest human representative currently identified, Sahelanthropus tchadensis. Nevertheless, there is no consensus on its modalities and age, notably due to the lack of fossil remains. The acquisition of bipedalism is considered to be a decisive step in human evolution. Credit: © Franck Guy / PALEVOPRIM / CNRS – University of Poitiers This analysis enables us to understand the variations of mechanical constraints on the femur and to interpret these constraints in terms of locomotor mode. 3D cortical thickness variation map for the femurs of (from left to right) Sahelanthropus, an extant human, a chimpanzee and a gorilla (in posterior view). Right: Example of analysis performed to interpret the locomotor mode of Sahelanthropus tchadensis. From left to right: the femur, in posterior and medial view the right and left ulnae, in anterior and lateral view. Left: 3D models of the postcranial material of Sahelanthropus tchadensis.
0 Comments
Leave a Reply. |