Contemporary hominin locomotor diversity

Abstract: This year marks the 50th anniversary of the discovery of the renowned “Lucy” skeleton in Ethiopia (1). Remarkably preserved and dated to 3.2 million years ago (Ma), “Lucy” confirmed that the ability to walk on two legs (bipedalism), not large brains or small teeth, was one of the first major hominin adaptations. In the ensuing 50 years, the number of accepted hominin species tripled, and several studies revealed different types of bipedalism in hominins. However, whether such distinct types of locomotion occurred simultaneously and in the same location remained unclear. On page 1004 of this issue, Hatala et al. (2) describe 1.5- Ma footprints from two hominin species at the site of Koobi Fora, Kenya, that indicate different types of bipedalism at the same time and place. The findings help to elucidate the complex evolutionary history of hominin locomotion and suggest that different hominins may have interacted across habitats.