The reign of woolly rhinos, which lasted for millions of years, came to an abrupt end some 14,000 years ago, with Siberia being the final venue of their long tenure on Earth.
Human overhunting and the end of the last ice age are the two causes typically attributed to their demise, though a thorough understanding of the reasons for their extinction is sorely lacking. New genetic evidence published [August 13] in Current Biology is adding color to this tumultuous period of our planet’s evolutionary history, showing that it was climate change that put an end to this species.
With their colleagues, researchers Edana Lord and Nicolas Dussex from the Centre for Palaeogenetics—a joint venture between Stockholm University and the Swedish Museum of Natural History—sequenced the genomes of 14 woolly rhinos, extracting DNA from preserved tissue, bone, and hair samples. The team devised estimates of woolly rhino population sizes over time by sequencing a complete nuclear genome and by assembling over a dozen mitochondrial genomes, the latter technique providing an estimate of female population sizes.
Humans, as we’re learning, were active in northern Asia some 30,000 years ago, long before the disappearance of this species. What’s more, the apparent stability of woolly rhinos during this expansive period suggests humans played a minor, if not negligible, role in their demise.