New human ancestor species discovered

Scientists have discovered a new human ancestor species in Ethiopia that lived alongside the famous 'Lucy' up to 3.5 million-years ago.
Upper and lower jaw fossils recovered from the Woranso-Mille area of the Afar region of Ethiopia have been assigned to the new species Australopithecus deyiremeda.
This hominin unearthed by an international team of scientists lived alongside the famous "Lucy's" species, Australopithecus afarensis.
Lucy's species lived from 2.9 million years ago to 3.8 million years ago, overlapping in time with the new species Australopithecus deyiremeda.
The new species is the most conclusive evidence for the contemporaneous presence of more than one closely related early human ancestor species prior to 3 million years ago, researchers said.

Australopithecus deyiremeda differs from Lucy's species in terms of the shape and size of its thick-enamelled teeth and the robust architecture of its lower jaws.

The anterior teeth are also relatively small indicating that it probably had a different diet.
"The new species is yet another confirmation that Lucy's species, Australopithecus afarensis, was not the only potential human ancestor species that roamed in what is now the Afar region of Ethiopia during the middle Pliocene," said lead author and project team leader Dr Yohannes Haile-Selassie, from The Cleveland Museum of Natural History.
"Current fossil evidence from the Woranso-Mille study area clearly shows that there were at least two, if not three, early human species living at the same time and in close geographic proximity," said Haile-Selassie.

The combined evidence from radiometric, paleomagnetic, and depositional rate analyses yields estimated minimum and maximum ages of 3.3 and 3.5 million years.
"This new species from Ethiopia takes the ongoing debate on early hominin diversity to another level," said Haile-Selassie.
Scientists have long argued that there was only one pre-human species at any given time between 3 and 4 million years ago, subsequently giving rise to another new species through time.
However, the naming of Australopithecus bahrelghazali from Chad and Kenyanthropus platyops from Kenya, both from the same time period as Lucy's species, challenged this long-held idea.
Although a number of researchers were sceptical about the validity of these species, the announcement by Haile-Selassie of the 3.4 million-year-old Burtele partial foot in 2012 cleared some of the scepticism on the likelihood of multiple early hominin species in the 3 to 4 million-year range.

The Burtele partial fossil foot did not belong to a member of Lucy's species. However, despite the similarity in geological age and close geographic proximity, the researchers have not assigned the partial foot to the new species due to lack of clear association.
The research appears in the journal Nature.