Wednesday, June 30, 2021

Scientists hail stunning 'Dragon Man' discovery

 

Dragon Man Skull
Photo: BBC News Website
            Recently, the BBC News Website reported that Chinese researchers have unveiled an ancient skull that could belong to a completely new species of human. Scientists claim that it is our closest evolutionary relative among known species of ancient human, such as Neanderthals and Homo erectus. The specimen represents a human group that lived in East Asia at least 146,000 years ago.

Although the skull was found at Harbin, north-east China, in 1933, it only came to the attention of scientists recently. Prof Chris Stringer from London's Natural History Museum, a leading UK expert in human evolution, and a member of the research team, said:

"In terms of fossils in the last million years, this is one of the most important yet discovered… What you have here is a separate branch of humanity that is not on its way to becoming Homo sapiens (our species) but represents a long-separate lineage which evolved in the region for several hundred thousand years and eventually went extinct."

This remarkable discovery has the potential to rewrite the story of human evolution. Analysis suggests that it is more closely related to Homo sapiens than it is to Neanderthals.  Researchers have assigned the specimen to a new species: Homo longi, from the Chinese word "long", meaning dragon. The skull is huge compared with the average skulls belonging to other human species. Its brain was comparable in size to those from our species.

Artist's impression of what Dragon Man may have looked like
Photo: BBC News Website
            The Harbin human cranium is one of the best-preserved of all archaic human fossils, and important for understanding the diversification of the Homo genus and the origin of Homo sapiens. It represents a new human lineage evolving in East Asia and is       a member of the sister group of H. sapiens.

Around 100,000 years ago there were several different groups of humans including modern humans, Neanderthals and Denisovans.

Neanderthals

The Neanderthals thrived in Europe for around 300,000 years before modern humans arrived. Excavations in Ibex, Vanguard, and Gorham’s Caves in Gibraltar have revealed evidence of Neanderthal occupation dating to possibly as late as 28,000 years ago. This makes Gibraltar the most recent Neanderthal occupation site yet discovered.

Reconstruction of what Neanderthals may have looked like
            Current research shows that Neanderthals were, and continue to be, an integral part of modern humanity. Our prehistoric cousins did not completely disappear from the earth, as their presence can still be identified within modern DNA. A jawbone from a man who lived 40,000 years ago reveals that six to nine percent of his genome is Neanderthal, the highest amount ever found in a modern human specimen. This remarkable find indicates that a Neanderthal was in his family as close as four generations back in his family tree - potentially his Great-Great Grandfather!

Denisovans

The Denisovans were a mysterious human species living in Asia before modern humans like us expanded across the world tens of thousands of years ago. Until recently, the only fossils came from a few fragments of bone and teeth from a single site in Siberia - Denisova Cave.

Artist's impression of a Denisovan

"In many ways, Denisovans resembled Neanderthals but in some traits, they resembled us and in others they were unique," said Prof Liran Carmel, a researcher at the Hebrew University of Jerusalem.

Scientists have found evidence that the Denisovans lived at high altitudes in Tibet, passing on a gene that helps modern people cope at similar elevations Present-day Sherpas, Tibetans and neighbouring populations have a gene variant, which was probably acquired when Homo sapiens mixed with the Denisovans thousands of years ago.

Professor Jean Jacques Hublin, from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, said:

"We can only speculate that living in this kind of environment, any mutation that was favourable to breathing an atmosphere impoverished in oxygen would be retained by natural selection."

Nesher Ramla Homo Type

Researchers working in Israel have identified a previously unknown type of ancient human that lived alongside our species more than 100,000 years ago. They believe the remains uncovered near the city of Ramla represent one of the "last survivors" of a very ancient human group. The finds consist of a partial skull and jaw from an individual who lived between 140,000 and 120,000 years ago. The scientists have named the newly discovered lineage the "Nesher Ramla Homo type".

Skull fragment and jawbone found near Ramla in Israel
Photo: BBC News Website
            The team thinks that early members of the Nesher Ramla Homo group were already present in the Near East some 400,000 years ago.

Conclusion

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.

A re-evaluation of early human remains and artefacts from Morocco has suggested that the advent of Homo sapiens may have to be put back by 100,000 years. Archaeologists and palaeontologists believe that the oldest of the fossils comes from 300,000 to 350,000 years ago.

Recent discoveries show that humans left Africa many times prior to 60,000 years ago, and that they interbred with other hominins in many locations across Eurasia. Around 50,000 years ago, an improvement in the global climate, leading to the appearance of habitable lands where once there was desert, may have provided the opportunity for modern humans to spread into Europe.

The Harbin skull represents a new human lineage evolving in East Asia and is a member of a sister group of H. sapiens that lived at least 146,000 years ago.

For more information see:

https://www.bbc.co.uk/news/science-environment-57432104

https://www.bbc.co.uk/news/science-environment-57586315

https://www.bbc.co.uk/news/world-49760240

https://www.bbc.co.uk/news/science-environment-48107498


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