More than 3 million years ago, our ancient human ancestors, including their toddler-aged children, were standing on two feet and walking upright, according to a new study published in Science Advances.
"For the first time, we have an amazing window into what walking was like for a 2½-year-old, more than 3 million years ago," says lead author, Jeremy DeSilva, an associate professor of anthropology at Dartmouth College, who is one of the world's foremost authorities on the feet of our earliest ancestors. "This is the most complete foot of an ancient juvenile ever discovered."
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 by Zeresenay (Zeray) Alemseged, a professor of organismal biology and anatomy at the University of Chicago and senior author of the study. Alemseged is internationally known as a leading paleontologist on the study of human origins and human evolution.