Scientists Finally Solve Mystery of Ancient Fossil Foot

"Sixteen years ago a group of anthropologists discovered 3.4-million-year-old fossilized foot bones in Ethiopia. While they suspected the foot belonged to an ancient human that likely lived alongside the species we know as Lucy, Australopithecus afarensis, without a skull or teeth to analyze, they couldn't be sure. What they did know is that unlike Lucy, which walked upright on arched feet like our own, the mystery foot had a grasping toe that was adapted for climbing trees."

"Now the same team that discovered the strange foot have finally solved the mystery. In a paper published Wednesday in Nature, the researchers describe other hominin fossils found in the same area as the appendage, which they nicknamed the Burtele foot. The findings confirm that Lucy lived alongside another hominin species called Australopithecus deyiremeda, which behaved rather differently from its A. afarensis peers."

"It's a really exciting discovery long-awaited for all of us who have been wondering what that crazy foot was, says University of Missouri anthropologist Carol Ward, who was not involved in the new study. Not only do we have different species living at pretty similar times in a similar area but they are navigating the world in a different way from one another, she says."

Fossilized foot bones dated to 3.4 million years ago showed a grasping toe adapted for climbing trees, unlike the arched, upright-footed Australopithecus afarensis. New hominin fossils recovered from the Burtele foot discovery site link that appendage to Australopithecus deyiremeda. Jawbones dated 3.5–3.3 million years and the new remains indicate that A. deyiremeda coexisted with A. afarensis in the same region. Morphological differences imply differing locomotor behaviors, with A. afarensis walking upright on arched feet and A. deyiremeda retaining arboreal adaptations. The findings resolve a long-standing anatomical mystery and were published in Nature.

Read at www.scientificamerican.com