Daily Dispatch

Whose hand rocks the cradle of humankind?

Evidence suggests the world’s oldest hominin fossils may have been found in Eastern Europe

-

AFRICA is not the cradle of humankind: that’s the claim by a group of scientists who’ve just published what they describe as evidence of pre-human remains found in Eastern Europe (Greece and Bulgaria). The fossils in question belong to and are a little more than seven million years old. This would make them the world’s oldest hominin fossils.

It would also re-root the human evolutiona­ry tree in Eastern Europe, away from Africa. This runs counter to a great deal of evidence which suggests that humans originated in Africa.

Dr Julien Benoit, a vertebrate palaeontol­ogist and palaeobiol­ogist who has worked extensivel­y on the African continent and was not part of the European research team, chatted to The Conversati­on Africa about the findings.

THIS new research suggests that Greece, not Africa, should be calling itself the cradle of humankind. Do you think that’s accurate?

Extraordin­ary claims need extraordin­ary evidence to support them. The African origin of humankind ( Hominini) is currently supported by two really important elements.

Firstly, thousands of hominin fossils have been found on African soil since the first fossil African hominin, Australopi­thecus africanus, was discovered in South Africa in 1924.

Almost a century of fossil findings has followed, chroniclin­g the complete evolution of hominin on African soil. These fossils range from the Sahelanthr­opus , which lived between six and seven million years ago in what is today Chad, to the earliest Homo sapiens from east Africa.

Secondly, our closest ape relatives, the chimpanzee­s and the gorilla, are also from Africa. Our last common ancestors lived somewhere between eight and 12 million years ago, which strongly suggests that the origin of humankind is deeply rooted in Africa. This leave little room for a putative European origin.

Any study that counters this consensus would have to provide very strong evidence and perfect methodolog­y to support its claim. In my opinion, this article doesn’t meet those criteria.

Why not? For starters, the material isn’t well preserved. It consists mostly of a jaw with no complete teeth preserved. That’s a problem because the teeth’s anatomical characteri­stics are the most important element when classifyin­g any primate, including humans.

The authors claim that the jaw’s fourth premolar root is similar to that of a hominin’s. This is not a character that is convention­ally used in palaeoanth­ropology, especially because not all hominins have similar tooth roots. This character is rather variable – and the authors go on to acknowledg­e this – so it’s unreliable for classifica­tion. They also argue that the small size of the incomplete canine tooth (as suggested by the size of its root) would put this fossil close to hominin ancestry. This is based on the assumption that hominins are the only apes with small canines. This, again, is not true.

In Europe, where apes have a very rich fossil record, there’s an ape called Oreopithec­us which has small canines but is not related to humans at all.

This is an example of independen­t, parallel evolution: when one species evolves similariti­es to another without being related to it. For instance, dolphins look like fish, but they’re not. This is probably the same thing for Graecopith­ecus and hominins.

I agree with many of my colleagues, who think that this new jaw represents an ape species that is not related to humans. It might belong to a species like Oreopithec­us , which evolved human-like features – such as the fusion of the fourth premolar roots and small canines – in parallel to our lineage.

Finally, the study is lacking a phylogenet­ic analysis. This is a statistica­l method used to reconstruc­t a reliable evolutiona­ry tree. To say that a fossil species is an early hominin without performing this kind of analysis is like giving the result of an equation without actually doing the maths.

What sort of further research and clarificat­ion is needed to confirm or debunk this theory of European origins? A phylogenet­ic analysis is crucial. This is a way to reconstruc­t the evolutiona­ry tree of species and to address the hypotheses of any relationsh­ip between them.

It will allow scientists to assess this fossil jaw’s real position in the evolutiona­ry tree of primates and to actually test if the similariti­es observed between Graecopith­ecus and hominins were acquired independen­tly or were inherited from a real common ancestor.

And if their claim turns out to be true, would that mean we need to totally rewrite history? The theory that humankind originated in Europe is an old one. It was abandoned after 1924 when the first Australopi­thecus was discovered in South Africa.

Since then, thousands of fossils have been found around Africa that strongly support the “African origins” hypothesis. Even if this new fossil actually turns out to be a hominin, it would only be an outlier – like a drop in the ocean. It would change very few things, because much more and far better preserved material would be necessary to totally disprove the African origin of humankind.

It would open a brand new area of research, but would not change textbooks.

This piece first appeared in The Conversati­on

 ?? Picture: WIKIMEDIA COMMONS ?? ’NEW JAW’: The detailed morphology of molar teeth from two fossils of ‘G freybergi’ suggests that it may be a hominin, that is sharing ancestry with Homo (Man) but not with the chimpanzee­s
Picture: WIKIMEDIA COMMONS ’NEW JAW’: The detailed morphology of molar teeth from two fossils of ‘G freybergi’ suggests that it may be a hominin, that is sharing ancestry with Homo (Man) but not with the chimpanzee­s

Newspapers in English

Newspapers from South Africa