Denisova Cave in Siberia ’s Altai Mountains is the only spot on the satellite that ’s known to have been lived in by Denisovans , Neanderthals , andHomo sapiens . By analyse traces of DNA leave behind by these three human lineages , research worker have now reconstructed the cave ’s chronology , revealing precisely when each mintage moved into the prehistoric hot spot .
Theiconic caveconsists of three compartments , know as the Main , East , and South Chambers . premature analysis of the Main and East sections have helped to illuminate some aspects of the site ’s account , and the authors of a new work have now filled in the gap by document the ancient human and animate being mitochondrial deoxyribonucleic acid in the South Chamber .
In total , the researchers retrieve 213 sample distribution of human hereditary material , with the sometime Denisovan DNA occurring in layers of sediment dated to around 250,000 years ago . The earliestDenisovan fossilsand rock tools , meanwhile , are about 200,000 years old , suggesting that this extinct hominid was still around at the time when Neanderthals first took up residence inDenisova Cave .
A collection of prehistoric human remains and stone tools from Denisova Cave.Image credit: OlgaMed/Shutterstock.com
harmonise to the study authors , the first traces of Neanderthal DNA seem shortly after 200,000 age ago , although the absolute majority of fossils from this coinage are dated to between 150,000 and 80,000 years ago . Intriguingly , the assemblage in the South Chamber more than doubles the cave ’s concentration of Denisovan DNA succession from the period between 80,000 and 50,000 yr ago , when other human groups were present at the site .
As for our own coinage , it seems we arrived on the scenery after Neanderthals had become extinct , making our home in Denisova Cave between 25,000 and 20,000 days ago . Among the traces of modern human DNA bump in the South Chamber were two samples retrieve from adeer tooth pendent , which was in all probability worn by a distaff individual descended from a group of north Eurasian humans that came from the east .
Based on this timeline , the survey writer suggest that subsequent human species may have propel in and out of Denisova Cave as fluctuations in the Ice Age climate make suitable conditions for different groups . For instance , the researcher explain that “ [ the ] habitat was least golden for Denisovans and most suitable for Neanderthals during the last two interglacial period . ”
However , an analysis of the animal desoxyribonucleic acid within the South Chamber indicated that no major turnover in the cave ’s faunal population occurred at the prison term thatDenisovansdisappeared , suggesting that clime change may not have drive this ancient hominid from the sphere . alternatively , the researchers hypothesize that “ competition for resource or encounters with modern humans ” may have leave in Denisovans being evicted from their ancestral menage .
The study is published in the journalNature Communications .
