The interdisciplinary team of palaeontologists and palaeogeneticists analyzed ancient DNA and fossil data to trace changes in biodiversity across the Northern Hemisphere. Their findings indicate that the evolution of species like the woolly mammoth, musk ox, and arctic fox began around 2.6 million years ago, coinciding with the onset of permanent polar ice.
Approximately 700,000 years ago, glacial cycles became longer, and many cold-adapted species either emerged or diversified in response. This marks the period when modern Arctic species and now-extinct megafauna evolved to cope with extended cold spells.
"The cold-adapted species are amongst the most vulnerable animals and plants to ongoing climate change. Therefore, an understanding of how species evolved in the past is essential to help us understand the risks faced by endangered species today," said Professor John Stewart, who led the study.
Researchers also compared evolutionary timelines of mammals with those of plants and beetles. Their analysis challenges previous assumptions that some cold-resilient organisms originated earlier in the polar regions. The data suggest that Arctic ecosystems formed in complex stages, with different species arriving at different times.
The study provides evidence that reindeer and true lemmings may have first appeared in the Arctic between one and two million years ago, while arctic foxes and polar bears likely arrived from southern regions within the last 700,000 years. In contrast, species such as the woolly rhinoceros appear to have evolved further south in steppe grasslands, with early signs of their presence on the Tibetan Plateau.
"This is the first concerted effort to compare the evolution of cold-adapted animals and plants since modern methods of palaeogenetics appeared," Stewart added. "We can now build on these findings to understand more about how more cold-adapted species evolved and how the Arctic ecologies arose in the past and use this to help conservation efforts in the future."
Research Report:The progressive evolution of cold-adapted species
Related Links
Bournemouth University
Beyond the Ice Age
| Subscribe Free To Our Daily Newsletters |
| Subscribe Free To Our Daily Newsletters |
