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