Fossils Confirm 3.4-Million-Year-Old Foot as A. deyiremeda

Newly discovered fossils in Ethiopia have confirmed that a mysterious 3.4-million-year-old foot, unearthed more than a decade ago, belonged to Australopithecus deyiremeda, an ancient human relative that coexisted with the species of the famed Lucy skeleton, scientists announced in a study published Wednesday in the journal Nature.

The foot bones, found in 2009 at the Burtele site in the Afar region of northeastern Ethiopia as part of the Woranso-Mille paleontological project, consist of eight fragments from a right foot. Unlike the arched, upright-walking feet of Australopithecus afarensis, Lucy's species, the Burtele foot featured a curved, opposable big toe suited for grasping tree branches, indicating its owner spent significant time climbing. At the time, researchers led by Yohannes Haile-Selassie of Arizona State University suspected it came from a different hominin but could not identify the species without additional evidence.

In 2015, Haile-Selassie's team named A. deyiremeda based on nearby jaw and tooth fossils dated to 3.3 to 3.5 million years ago. Those remains suggested a more primitive hominin than A. afarensis, but linking them to the foot remained uncertain due...