After a thorough examination of the skull, which is estimated to be one million years old, the research team concluded that Homo sapiens emerged as a distinct species approximately 400,000 years earlier than previously thought.
What Did the Scientists Report?
The Yunxian 2 skull, discovered in Hubei Province, China, in 1990, has recently been at the center of taxonomic confusion. One reason for this is the significant deformation of the specimen, which hindered its study.
Using computed tomography and digital reconstruction methods, the authors of the new study corrected the skull’s distortions and created a complete model. They found that Yunxian 2 exhibits a range of features, some of which are characteristic of more primitive hominids like Homo erectus, while others align more closely with Homo sapiens.
By comparing over 500 morphological traits with 104 other fossils, anthropologists determined that Yunxian 2 belongs to the clade Homo longi, which includes a skull dated to 145,000 years ago, recently identified as Denisovan. However, Yunxian 2 is not a Denisovan skull.
Moreover, while it was previously thought that Denisovans and Neanderthals were closely related groups, the analysis revealed that Homo longi is actually a sister group to .
“Since the Yunxian 2 skull is about a million years old, the clade Homo longi must be at least around a million years old as well. This could mean that if sapiens and Neanderthals had already diverged, their groups must have a similar or even older origin,” said Professor Chris Stringer, one of the world’s leading anthropologists and co-author of the study, in an interview with IFLScience.
In other words, the Homo sapiens species emerged over a million years ago, which is about 400,000 years earlier than previous studies indicated. Researchers now believe that our species diverged around 1.02 million years ago, while the Homo longi group diverged about 1.2 million years ago.
Interestingly, this group also includes Homo antecessor, represented by a fossil that is 850,000 years old from the Atapuerca archaeological site in Spain. Thus, geographically, early members of this group were widespread across Eurasia, suggesting that this group may have originated outside of Africa.
Scientists have long asserted that Homo sapiens first emerged in Africa. However, Professor Stringer does not rule out the possibility that our species could have descended from a hominin that returned to the continent after our ancestral lines branched off somewhere in Eurasia.
The team now hopes to clarify this uncertainty by analyzing other ancient human remains from Ethiopia, Eritrea, and Spain.
The findings of the study were published in the journal Science.