Denisova Cave is the only site in the world known to have been occupied by both Denisovans and Neanderthals at various times. Two new studies published in the journal Nature, now put a timeline on when the two groups of archaic humans (hominins) were present at the site and the environmental conditions they faced before going extinct. The studies identify the age of the earliest Denisovans and Neanderthals in Southern Siberia. One of the studies, was led by Dr Katerina Douka from the Max Planck Institute for the Science of Human History, while the other one was led by Zenobia Jacobs of the University of Wollongong in Australia.