A new study claims that the split of the common lineage of great apes and humans probably occurred in Europe and not in Africa. The bold hypothesis is based on an analysis of 7.2-million-year-old fossil remains.
As of now, it was widely believed that the human lineage split from that of apes some 7 million years ago in Africa.
According to the new study, the common lineage of great apes and humans split several hundred thousand years earlier than assumed until now.
The findings have been published in two papers in the journal PLOS ONE.
• The research team analysed the two known specimens of the fossil hominid Graecopithecus freybergi: a mandible (lower jaw) from Greece and an upper premolar tooth from Bulgaria.
• Using computer tomography, the researchers visualised the internal structures of the fossils and demonstrated that the roots of premolars are widely fused.
• Great apes typically have two or three separate and diverging roots, whereas the roots of Graecopithecus converge and are partially fused, which is a feature that is characteristic of modern humans, early humans and several pre-humans including Ardipithecus and Australopithecus.
• The lower jaw, nicknamed 'El Graeco' by the scientists, has additional dental root features, suggesting that the species Graecopithecus freybergi might belong to the pre-human lineage.
• Furthermore, Graecopithecus is several hundred thousand years older than the oldest potential pre-human from Africa, the six to seven million year old Sahelanthropus from Chad.
• The research team dated the sedimentary sequence of the Graecopithecus fossil sites in Greece and Bulgaria with physical methods and got a nearly synchronous age for both fossils: 7.24 and 7.175 million years old.