HumansHuman ancestors may have walked on two legs 7 million years ago An analysis of thigh and forearm bones from Sahelanthropus tchadensis suggests the early hominin was mainly bipedal, but the claim is controversial 51¶¯Âþ
HumansPeople instinctively run at their most energy-efficient speed Findings from people running in the lab and in the real world show that men and women tend to run at a speed that minimises energetic costs, though men run faster 51¶¯Âþ