A major decline in plant diversity resulted in the extinction of the woolly mammoth, woolly rhinoceros and many other large animals following the last Ice Age, according to a new study published in the journal Nature.
Relying on DNA-based research, the Centre for GeoGenetics at the Natural History Museum of Denmark has found that the flowering plants that mammoths and other large creatures depended on for survival disappeared from North American and northern Asia during the last glacial period, eliminating a major food source for the animals.
Prior the that period, the landscapes of the Northern hemisphere were far more diverse and stable than today’s steppes, with megafauna like woolly rhinos and mammoths feeding on grasses and protein-rich flowering plants, or forbs.
But at the height of the last Ice Age – 25,000-15,000 years ago, at a time when the climate was at its coldest and driest – a major loss of plant diversity occurred, the study’s authors wrote.
As a result, the giant animals barely survived.
Once the Ice Age ended about 10,000 years ago the climate warmed again. However, the protein-rich forbs did not recover to their former abundance and were replaced with different kinds of vegetation, including grasses prevalent on today’s plains and steppes.
“This likely proved fatal for species like woolly rhino, mammoth, and horse in Asia and North America,” according to the University of Copenhagen. “Even though it became warmer again after the end of the Ice Age the old landscapes did not return.”