A controversial new study suggests that the fossil of an ape's jawbone may shed new light on the origins of Homo sapiens.
The Jawbone
First discovered during World War II by German soldiers in Greece, the fossil was in very poor condition - nothing more than a mandible with the teeth chipped away. Most paleontologists didn't know what to do with the specimen.
Recently, David R. Begun, a paleobiologist at the University of Toronto, studied the fossil and made some interesting discoveries. Begun's analysis revealed that the fossil was more than 7 million years old had some human characteristics.
The Theory
Begun and his team claim that the fossil could represent humanity's oldest ancestor and, to make things even more controversial, he suggests that the fossil is evidence that humanity diverged from apes living in southern Europe as opposed to Africa.
Begun's claims are not widely supported by the scientific community as the generally held consensus is that the original home of Homo sapiens was Africa.
"David Begun has repeatedly proposed that the African ape and human clade arose in Europe and that gorillas, chimps and humans arose from an early European member of this group that migrated into Africa," John Kelley, a paleontologist at Arizona State University's Institute of Human Origins, told the Washington Post. "This 'back into Africa' scenario has garnered few if any adherents."
The Study
The jawbone is believed to come from a species that has been named Graecopithecus freybergi. Upon analyzing the jaw via a CT scan, researchers found that the jaw does contain some human characteristics.
"The canine root was very short," said Begun. "The premolar roots were simplified, partly fused. Both of those characteristics we find only in members of human lineage."
Despite Begun's work, most researchers remain unconvinced. New York University's Susan C. Antón admitted that there was a possibility that Homo sapiens originated in Asia rather than Africa, but added it was unlikely. The simplest and most widely held view remains the African origin.
Beyond that, some have argued that Begun's research is based on incomplete data as we do not have a full model of the specimen's jaw.
"The evidence that canine root reduction indicates the hominin status of Graeco is also not very convincing," said the Smithsonian's Richard Potts, who notes that the crown had snapped off, making it impossible to study the fossil in the context of the entire tooth. "So there's little basis for accepting the exceptional claim that a 7.2-million-year-old fossil from Greece is the oldest known human ancestor!"
Begun himself notes that the study is far from perfect, but is planning an expedition to find more samples for study.
