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Fossil jaw sheds light on turning point in human evolution

This 2013 photo provided by Kaye Reed shows the LD 350-1 mandible just steps from where it was sighted in Ethiopia by Chalachew Seyoum, an ASU graduate student. The jawbone fragment is the oldest known fossil from an evolutionary tree branch that eventually led to modern humans, scientists reported on Wednesday, March 4, 2015. At about 2.8 million years old, the partial jawbone pushes back the fossil record by at least 400,000 years for our branch, which scientists call Homo. (AP Photo/Kaye Reed) This 2013 photo provided by Kaye Reed shows the LD 350-1 mandible just steps from where it was sighted in Ethiopia by Chalachew Seyoum, an ASU graduate student. The jawbone fragment is the oldest known fossil from an evolutionary tree branch that eventually led to modern humans, scientists reported on Wednesday, March 4, 2015. At about 2.8 million years old, the partial jawbone pushes back the fossil record by at least 400,000 years for our branch, which scientists call Homo. (AP Photo/Kaye Reed)

By Associated Press March 4, 2015 1 min read

NEW YORK (AP) – Scientists say a fragment of jawbone found in Ethiopia is the oldest known fossil from an evolutionary tree branch that eventually led to modern humans.

The fossil comes from very close to the time that our branch split away from more ape-like ancestors that are best known for the fossil skeleton Lucy. So it gives a rare glimpse of what very early members of our branch looked like. Our branch is called Homo.

The fossil is about 2.8 million years old. Its discovery was reported Wednesday in the journal Science.