At least three hominins (Denisovans, Neanderthals, and early Homo sapiens) and large cave-dwelling carnivores (hyena, wolves, and even bears) used Denisova Cave over a span of 300,000 years, according to researchers who analyzed charcoal from ancient fires, coprolites (fossil animal droppings) and bone fragments from the famous cave site. Their results appear in the journal Scientific Reports.
Denisova Cave in the Altai Mountains of southern Siberia. Image credit: Alex Demin / CC BY-SA 4.0.
Situated in the foothills of the Altai Mountains in southern Siberia, Denisova Cave occupies a prominent place in world prehistory due to the hominin fossils and ancient DNA recovered from the site.
These finds revealed two archaic human populations: Denisovans, identified through genome sequencing of fossils; and Neanderthals, who are at the eastern limits of their known range at this site.
“These hominin groups and large carnivores such as hyenas and wolves left a wealth of microscopic traces that illuminate the use of the cave over the last three glacial-interglacial cycles,” said study lead author Dr. Mike Morley, a researcher at Flinders University and the University of Wollongong.
A portrait of a juvenile female Denisovan based on a skeletal profile reconstructed from ancient DNA methylation maps. Image credit: Maayan Harel.
“Our results complement previous work by some of our colleagues at the site that identified ancient DNA in the same dirt, belonging to Neanderthals and a previously unknown human group, Denisovans, as well as a wide range of other animals,” he said.
“But it now seems that it was the animals that mostly ruled the cave space back then.”
From their ‘micromorphology’ examination of the dirt found in the cave, the scientists discovered clues about the use of the cave, including fire-use by ancient humans and the presence of other animals.
Summary stratigraphic logs of the sequences exposed in the Main and East Chambers of Denisova Cave, showing the locations of the micromorphological samples and key microstratigraphic features. To the right of each log, optical ages (in thousands of years, with uncertainties at 95.4% probability) are shown for the major boundaries between lithological units in the thin sections, together with the associated archaeological phases. Image credit: Morley et al, doi: 10.1038/s41598-019-49930-3.
“This study is very significant because it shows how much can be achieved by sifting through sedimentary material using advanced microscopy and other archaeological science methods to find critical new evidence about human and non-human life on Earth,” said University of Wollongong’s Richard (Bert) Roberts, co-author of the study.
“Using microscopic analyses, our latest study shows sporadic hominin visits, illustrated by traces of the use of fire such as miniscule fragments, but with continuous use of the site by cave-dwelling carnivores such as hyenas and wolves.”
“Coprolites indicate the persistent presence of non-human cave dwellers, which are very unlikely to have co-habited with humans using the cave for shelter.”
“This implies that ancient groups probably came and went for short-lived episodes, and at all other times the cave was occupied by these large predators.”
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Mike W. Morley et al. 2019. Hominin and animal activities in the microstratigraphic record from Denisova Cave (Altai Mountains). Scientific Reports 9, article number: 13785; doi: 10.1038/s41598-019-49930-3
Source link: https://www.sci.news/archaeology/denisova-cave-07634.html
