he geographic separation and climate preferences of Neanderthals and Denisovans led to their interbreeding during warm periods, when atmospheric carbon dioxide levels increased and the climate became warmer. This allows scientists to conclude that climate change can influence the genetic diversity and evolution of different species.
The study by scientists from Busan National University and the University of Naples is based on data on ancient humans, including genetic data as well as climate modeling using a supercomputer. The scientists found that Neanderthals and Denisovans had different climate preferences: Denisovans were more adapted to cold conditions, while Neanderthals preferred more temperate forests and grasslands.
This geographic division of habitat meant that Neanderthals typically lived in southwestern Eurasia and Denisovans in the northeast. However, during warm periods, when carbon dioxide levels rose and glaciers melted, the habitats of the two species began to overlap, increasing the likelihood of interbreeding.
The findings confirm known episodes of ancient interbreeding that occurred 120,000, 78,000 and 90,000 years ago. This means that climate change may play an important role in the evolution and genetic diversity of different species.
In addition, the study allowed scientists for the first time to assess the possible habitats of the Denisovans. It turned out that in addition to areas in Russia and China, northern Europe could also have been a suitable environment for them. However, to confirm the presence of Denisovans west of the Altai Mountains, genetic analysis of European populations is needed.
Additional climate data may also help explain the interbreeding episodes that occurred 210,000 and 320,000 years ago. The study shows that climate change has played and continues to play an important role in the evolution of the human species.