Human ancestors started walking upright on two feet over seven million years ago, study suggests

Anatomy of thigh bone indicative of bipedalism of human ancestor species on land

Scientists have found that one of the earliest known human ancestors was walking on two legs as far back as seven million years ago, building on previous analyses that came to similar conclusions.

In the new research, published on Wednesday in the journal Nature, scientists assessed thigh and forearm fossils of the hominin Sahelanthropus tchadensis unearthed in Toros-Menalla in Chad in 2001.

The species of early hominin – an evolutionary group that includes modern humans and our extinct relatives – was dated to around seven million years ago.