- Jun 2014
Credit: Jeremy DeSilva
A nearly complete foot from Dikika, Ethiopia and its implications for the ontogeny and function of Australopithecus afarensis | Science Advances A nearly complete foot from Dikika, Ethiopia and its implications for the ontogeny and function of Australopithecus afarensis We analyze a nearly complete, 3.32-million-year-old juvenile foot of A. afarensis (DIK-1-1f). We show that juvenile A. afarensis individuals already had many of the bipedal features found in adult specimens. However, they also had medial cuneiform traits associated with increased hallucal mobility and a more gracile calcaneal tuber, which is unexpected on the basis of known adult morphologies. Selection for traits functionally associated with juvenile pedal grasping may provide a new perspective on their retention in the more terrestrial adult A. afarensis.
The tiny foot, about the size of a human thumb, is part of a nearly complete 3.32-million-year-old skeleton of a young female Australopithecus afarensis discovered in 2002 in the Dikika region of Ethiopia this youngster lived more than 200,000 years before Lucy.
Based on the skeletal structure of the child's foot, specifically, the base of the big toe, the kids probably spent more time in the trees than adults. "If you were living in Africa 3 million years ago without fire, without structures, and without any means of defense, you'd better be able get up in a tree when the sun goes down," added DeSilva. "These findings are critical for understanding the dietary and ecological adaptation of these species and are consistent with our previous research on other parts of the skeleton especially, the shoulder blade," Alemseged noted. https://www.sciencedaily.com/releases/2018/07/180704151911.htm