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| A 210,000-year-old human skull found in Greece Source: Esben 468635/Adobe stock |
The website https://www.ancient-origins.net/
reports that a 210,000-year-old human skull found in
Greece in the 1970s could provide new evidence that our species left Africa
much earlier than previously thought. If the claim is verified, the
discovery will rewrite a key chapter of the human story, with the skull
becoming the oldest known Homo sapiens fossil in Europe by more than 90,000
years.
Early Expansion not Maintained
The first fossil evidence for any modern humans outside Africa comes from
the Middle East, from the archaeological sites of Skhul and Qafzeh in Israel,
dating to around 120,000 years ago. However, this early expansion of modern
humans was not maintained. A change to a colder climate may have driven those
pioneers back into Africa. The expansion of our own species out of Africa that
eventually led to the colonisation of the globe would start later – after
100,000 years ago.
A re-evaluation of early human remains and artefacts from Morocco has
pushed back the advent of Homo sapiens by 100,000 years.
Archaeologists and palaeontologists now think that the oldest of the fossils
comes from 300,000 to 350,000 years ago. Skulls, teeth, and long bones of at
least five Homo sapiens, along with stone tools and animal
bones, have been found at Jebel Irhoud, Morocco since 2004.
Stone Tools
Although stone tools were found all over Africa by 300,000 years ago, human
fossils were thought to be no older than 195,000 years old. One possibility was
that the stone tools had been made by some hominid (any member of the group
consisting of all modern and extinct humans and great apes - including
gorillas, chimpanzees, and orangutans - and all their immediate ancestors)
other than Homo sapiens. Jebel
Irhoud is the oldest and richest African Middle Stone Age hominin site that
documents early stages of the Homo sapiens.
Hominins, which may have originated in Africa up to 6 million years ago,
include all the species that emerged after the Homo genus,
split from that of chimpanzees. Humans and chimpanzees are very closely related
and separated about 7.4 million years ago.
There is only a 1% difference between the chimpanzee genome and our own
suggesting that we have a common ancestor.
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| Apidima 2 and its reconstruction. (c) Katerina Harvati, Eberhard Karls: University of Tubinggen |
Apidima Cave
The human skull from Greece was one of two cranial fossils found in
Apidima Cave, on the southwestern coast of the Peloponnese in
Greece. Both were initially
identified as Neanderthals. The discovery of these skulls
provides evidence of an earlier migration of people from Africa that left no
trace in the DNA of people alive today. One skull was very distorted and the
other incomplete. The more complete skull appears to be a Neanderthal. But the
other shows clear characteristics, such as a rounded back to the skull,
diagnostic of modern humans.
A multinational team from the University of Tubinggen in Germany, led by
Katerina Harvati, reconstructed the specimens digitally and dated them by
measuring their radioactive decay and confirmed that the skull known as Apidima
2 was an early Neanderthal dating from around 170,000 years ago. Scientists
also digitally recreated the skull known as Apidima 1 and found that it was
more likely a modern human (Homo sapiens), dating it to 210,000 years
ago.
Human fossils from
Daoxian and Zhirendong
Palaeontologists have discovered modern human
fossils from Daoxian and Zhirendong in China dating to between 80,000 and
120,000 years ago. DNA studies indicate that there was early interbreeding
between African humans and Neanderthals.
The new evidence from Apidima further extends our understanding of modern
human dispersal and interaction with other hominin
species. Human evolution has been thought of in terms of new
species developing and replacing older simpler ones. Modern humans were thought
to have left Africa and moved across the world from around 70,000 years ago
replacing the Neanderthals in Europe about 40,000 years ago. New fossil discoveries, improvements in their
dating and the advent of genetic evidence, has led to a reappraisal of the
distribution of modern humans.
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| Adult Male Cranium 'H.naledi' from Lesed 1 Chamber, Naledi, South Africa |
Neanderthals, Homo
naledi and Denisovans
Evidence from modern day Israel, Syria, Lebanon and Jordan, suggest the
first wave of modern humans out of Africa were replaced by Neanderthals, before
the final, more successful human migration that followed. In southern Africa,
modern humans were alive at the same time as a much smaller and seemingly more
primitive species called Homo
naledi . Genetic evidence from Siberia and Tibet has
identified a new hominin species – the Denisovans – that shared a history
of interbreeding
and interaction with Neanderthals. DNA analysis of our own
genomes shows that the Neanderthals bred with our own species.
People living today who are of European, Eurasian, and Asian descent have
well-identified Neanderthal-derived segments in their genome. Present-day
Africans, however, do not have detectable traces of Neanderthal DNA in their
genomes. This shows that whatever sexual contact occurred between modern humans
and Neanderthals happened among humans who left the African continent.
People living outside Africa today trace their ancestry to a migration
that left the continent around 60,000 years ago. As modern humans moved across
Europe and Asia, they largely replaced other species they met, such as the
Neanderthals and Denisovans.
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| Cranial features of Modern Man and Neanderthal compared |
If at least some early modern humans left Africa more than 210,000 years
ago, they may have settled in the Levant (Iraq, Syria, Lebanon, Cyprus, Turkey,
Israel and Jordan) before expanding west into Europe, which was already home to
Neanderthals. Scientists believe that any early human pioneers who did reach Europe
died out there, before the Neanderthals themselves were replaced by an influx
of Homo sapiens about 40,000 years ago.
Conclusion
A 210,000-year-old human skull found in Greece in the 1970s could provide
new evidence that our species left Africa much earlier than previously thought,
becoming the oldest known Homo sapiens fossil in Europe by more than 90,000
years. Some experts, however, question whether the skull really belonged to a
modern human. Concerns have also been expressed about the dating procedure
used. For now, at least, the jury is still out on this recent ‘Earth breaking’ discovery!
For further information see:
https://www.ancient-origins.net/
For further information see:
https://www.ancient-origins.net/
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