Researchers from Germany who analysed DNA taken from the Denisova Cave in Siberia have discovered that humans may have lived together with their close relatives the Denisovans and Neanderthals about 45,000 years ago.

A study by the Max Planck Institute in Germany, which included DNA analysis of 728 Pleistocene samples, suggested that early modern humans probably once lived alongside Denisovans and Neanderthals.

The Denisova Cave which is located in the Altai Mountains in southern Siberia gained world fame after the famous discovery of the Denisovans, which are an extinct race of archaic humans, that scientists believe occupied large parts of central and eastern Asia.

In addition, Neandertal remains have also been found at the site as well as a bone from a child who had a Neanderthal mother and Denisovan father, thus proving that both groups lived together in the region.

Nevertheless only eight bone fragments and teeth of Neanderthals and Denisovans have been recovered so far from the Denisova Cave which according to scientists cover a time period of over 300,000 years.

Since there are too few fossils to reconstruct the historical events from the cave, scientist have encountered difficulties to link the different types of stone tools and other artifacts to specific hominin groups (Denisovans, Neanderthals, modern humans) that lived in the Denisova Cave.

Therefore an international team of archaeologists, geneticists, geochronologists and scientist from other branches has been assembled by Dr Michael Shunkov of the Siberian Branch of the Russian Academy of Sciences in order to study the unique site and fill missing historical gaps.

Dr Richard ‘Bert’ Roberts from the University of Wollongong in Austria who is a part of the research told Newsflash: “The analysis of sediment DNA provides a wonderful opportunity to combine the dates that we previously determined for the deposits in the Denisova Cave with molecular evidence for the presence of people and fauna.”

Dr Zenobia Jacobs whose team of geochronologists collected over 700 sediment samples in a dense grid from the exposed sediment profiles in the cave said: “Just collecting these samples from all three chambers in the cave, and documenting their precise locations took us more than a week.”

After the samples arrived at the Max Planch Institute for Evolutionary Anthropology in the German city of Leipzig, lead author of the study Elena Zavala spent almost two years extracting and sequencing small DNA traces.

She said: “These efforts paid off and we detected the DNA of Denisovans, Neanderthals or ancient modern humans in 175 of the samples.”

During the DNA profile matching, the scientists involved in the study found out that the earliest hominin DNA belonged to the Denisovans indicating that they produced the oldest stone tools almost 250,000 – 170,000 years ago, when the Neanderthals arrived.

The Denisovans and Neanderthals shared the cave until 130,000-100,000 years ago when no Denisovan DNA was detected in the sediments.

Zavala explained that modern human mitochondrial DNA first appeared in layers of Initial Upper Paleolithic tools and other objects which are more diverse than the older ones and said: “This provides not only the first evidence of ancient modern humans at the site, but also suggests that they may have brought new technology into the region with them.”

The scientists also studied animal DNA and identified two time periods where changes occurred in both animal and hominin populations.

Svante Paabo said: “I believe that our Russian colleagues who excavate this amazing site have set the standards for many future archaeological excavations with their careful collection of many samples from each archaeological layer for DNA analysis.”

Senior author of the study Matthias Meyer said: “Being able to generate such dense genetic data from an archaeological site is like a dream come true, and these are just the beginnings. There is so much information hidden in sediments – it will keep us and many other geneticists busy for a lifetime.”