A breakthrough discovery has been made in Russia which will reveal more about an enigmatic early species of human . Paleo-archaeologists have now identified some skull fragments from the long-extinct species or subspecies of early hominins known as the Denisovans ( Homo denisova ). The find will add more to our knowledge of this ancient human and allow us to have a greater understanding of how it contributed to the evolution of modern people.

Experts are due to announce that they have confirmed the finding of the two pieces of a Denisovan skull, which is the first find of its kind. ‘Only four individual Denisovans had been identified previously’ reports Science Alert , and none of the previous fragments included parts of the skull. The discovery of the skull fragments is very important as it is only the fifth member of that species to have been found.

View of the entrance to the Denisova Cave archaeological site, Russia. ( Bence Viola/ Max Planck Institute for Evolutionary Anthropology )

Who were the Denisovans?

This historic find was made by a Russian team in a cave in the Altai mountains in Southern Siberia not far from Mongolia and Kazakhstan. The discovery was made in a deep cave and it is the fifth remains from an Denisovan individual to be found in this location. Known as the Denisova Cave , the early human species are named after this remote cavern.

The Denisovans emerged in Africa and it is believed that they are related to the Neanderthals. The two early human species separated approximately three quarters of a million years ago and both left Africa over a quarter of a million years ago. It is believed that Homo denisova ranged over a wide area of Asia and that they mated with Neanderthals and another unknown archaic human species . Scientists have not established when the archaic humans became extinct . Genetic testing has demonstrated that some ancient populations in Asia, such as the Papuans have inherited up to 5% of their DNA from their Denisovans ancestors.

Replica of a Denisovan finger bone fragment, originally found in Denisova Cave in 2008, at the Museum of Natural Sciences in Brussels, Belgium. ( CC BY-SA 3.0 )

Perhaps of all the various hominins, the Denisovans are the most mysterious. All that we really know about this human species is from the discoveries in the Denisova cave. Indeed, these early humans were only definitively identified in 2010 when a bone from the pinkie finger of a teenage girl was found in the Siberian cave. The only other remains found have been three teeth, and this is what makes the discovery of this hunk of a skull so important. Interestingly it appears that the Denisova cave was also inhabited by Neanderthals .

This bone fragment ('Denisova 11') was found in 2012 at Denisova Cave in Russia by Russian archaeologists and represents the daughter of a Neanderthal mother and a Denisovan father. ( T. Higham/ University of Oxford )

Denisovan skull fragments

The recent discovery consists of “two connecting fragments from the back, left-hand side of the parietal bone, which forms the sides and roof of the skull” according to the Daily Mail . The pieces when placed together are 5 inches by 3 inches (8 cm by 5 cm) in length. The two fragments were found some three years ago but were only announced recently because it took so long to identify the remains as from Homo denisova . DNA testing has proven that the skull fragments are from a Denisovan, but it has been impossible to date them.

The mysterious early humans

There have been other bones and even parts of skulls that have been found that may be from Denisovans. In 2017 some researchers believe that fragments of two Homo denisova skulls were found in Western China . However, the fragments found in the Siberian cave will not prove that the Chinese finds are from this extinct human. “Sadly, the newfound piece is not large enough to use to identify other skulls found elsewhere as Denisovan without genetic information to back the diagnosis up” reports Sapiens.

The findings from the Siberian cave are to be publicized at a session of the American Association of Physical Anthropologists. While the fragments are not large enough to transform our understanding of the archaic human they will almost certainly add to our knowledge of this enigmatic branch of the human family . It is hoped that there are more finds to be made in Asia that can help us to have a better understanding of this most mysterious hominin .

Top image: Representative image of skull discovery (not Denisovan) Source: Microgen / Adobe Stock

By Ed Whelan