Foot Fossil Confirms 2 Human Ancestor Species Existed 3.4 Million Years Ago-
A team of scientists has announced the discovery of a 3.4 million-year-old partial foot from the Woranso-Mille area of the Afar region of Ethiopia. The fossil foot did not belong to a member of "Lucy's" species, which is Australopithecus afarensis (the famous early human ancestor.) Research on this new specimen gives us reason to believe that more than one species of early human ancestor existed between 3 and 4 million years ago.
The partial foot was found in February 2009 in a local area that is known by Burtele. "The Burtele partial foot clearly shows that at 3.4 million years ago, Lucy's species, which walked upright on two legs, was not the only hominin species living in this region of Ethiopia," said lead author and project leader Dr. Yohannes Haile-Selassie, curator of physical anthropology at The Cleveland Museum of Natural History. "Her species co-existed with close relatives who were more adept at climbing trees, like 'Ardi's' species, Ardipithecus ramidus, which lived 4.4 million years ago."
The partial foot is the first evidence for at least two pre-human species with different methods of locomotion living at the same time in eastern Africa around 3.4 million years ago. The fossils were found below a sandstone layer. By using the argon-argon radioactive dating method, their age was estimated to be younger than 3.46 million years, "Nearby fossils of fish, crocodiles and turtles, and physical and chemical characteristics of sediments show the environment was a mosaic of river and delta channels adjacent to an open woodland of trees and bushes," said Saylor. "This fits with the fossil, which strongly indicates a hominin adapted to living in trees, at the same time 'Lucy' was living on land," said co-author Dr. Beverly Saylor of Case Western Reserve University. The big toe of the foot in Lucy's species is aligned with the other four toes for human-like bipedal walking, but the Burtele