Ethiopian fossil should shed light on mankind's first upright steps.
The remains of a hominid that date back nearly 4 million years have been uncovered by a field team in Ethiopia.
The discovery, announced in Addis Ababa on 4 March, looks set to provide crucial new evidence on early man's ability to walk upright.
Palaeoanthropologist Yohannes Haile-Selassie and his colleagues found the bones near Mille Town, about 520 kilometres northeast of Addis Ababa. “It is too early to tell what species is represented,” says Haile-Selassie, a curator at the Cleveland Museum of Natural History in Ohio.
A detailed description of the fossils will be submitted for publication once excavations and bone analysis are complete, which may not be for another year.
By studying the bones and muscle connections, anthropologists can decipher the mechanics of how different hominid species came to walk as they evolved from primates.
In addition to bones of the legs, hip and spine, the team uncovered a complete scapula, or shoulder bone. It is extremely rare to secure a scapula, as the thin bone is typically damaged by the forces of time.
The shoulder bone should provide important new data on arm and body functions. The leg bones indicate that the individual hominid was taller than Lucy (Australopithecus afarensis), a 3.2-million-year-old fossil found in 1974 about 60 km south of the new site.
Examination of animal fossils found with the new hominid specimen suggests that it lived between 3.8 million and 4 million years ago.
The team's preliminary analysis indicates the hominid is a form of Australopithecus. It may be an Australopithecus anamensis — known only by a few bones and teeth found in Kenya, where that species lived about 4 million years ago.
The director of the Cleveland Museum, palaeoanthropologist Bruce Latimer, is a co-leader of the project, but he was not in the field when the fossils were found. Fossils on the surface were immediately collected by the team to prevent them from being damaged. Digging is expected to begin later this year as the team looks for other specimens.