50 years ago, evidence showed that an extinct human ancestor walked upright
Excerpt from the February 16, 1974 issue of Science News
Leg and arm bones unearthed in Chad in 2001 hint that the extinct human ancestor Sahelanthropus tchadensis (illustrated) walked upright on the ground and in trees some 7 million years ago.
© Sabine Riffaut, Guillaume Daver, Franck Guy/Palevoprim/CNRS/Université de Poitiers
Fossils show man walked 3 million years ago — Science News, February 16, 1974
Anthropologist D. Carl Johanson … has discovered a skull fragment, shin and thigh bones of a 3-million-year-old man in Ethiopia…. The bones belonged to an ape man (hominid) of the genus Australopithecus.… “We have absolute, concrete evidence that our ancestors walked on two legs over 3 million years ago,” the 30-year-old scientist told a news conference.
Update
Exactly when upright walking emerged in the evolutionary history of humans remains hotly debated. Fossil analyses suggest that several hominid species ambled around on two legs about 5 million to 7 million years ago. An upper leg bone of the oldest known, 7-million-year-old Sahelanthropus tchadensis, bears signs of upright walking including an inner projection near the hip joint, scientists reported in 2022 (SN: 9/24/22). But not all paleoanthropologists are convinced those features prove a two-legged gait. And some scientists think the bone belonged to an ape that may have walked upright at times.
