A new study has revealed when and how animals like the woolly mammoth, musk ox, and arctic fox developed special adaptations to survive the extreme cold during the Ice Age.
Scientists found that many cold-weather species began evolving around 2.6 million years ago—when the Earth’s polar regions started to freeze permanently.
The research team, made up of paleontologists and paleogeneticists, examined ancient fossils and DNA to track the evolution of cold-adapted animals and plants in the Northern Hemisphere.
Their findings show that as Earth’s climate began to cool and ice sheets expanded and contracted, animals began to change in order to cope with the harsh, freezing conditions.
About 700,000 years ago, the Ice Age entered a new phase. The cold periods became longer, lasting twice as long as before.
This shift allowed many species we know today—including arctic foxes and polar bears—to move north and adapt to the cold.
It was also when now-extinct animals like the woolly mammoth and woolly rhinoceros appeared. Interestingly, some of these Ice Age giants may have evolved not in the Arctic but further south, in cold grassland regions such as the Tibetan Plateau.
The study, published in the journal Trends in Ecology and Evolution, is one of the first to closely compare the evolution of plants and animals in cold climates using modern DNA analysis.
Lead author Professor John Stewart from Bournemouth University explained that understanding how species adapted to cold climates in the past can help scientists predict how today’s animals and plants might respond to global warming.
The research also suggests that the timeline of Arctic life coming together—how and when the modern Arctic ecosystem formed—is still not fully understood.
While animals like true lemmings and reindeer may have evolved in the Arctic over a million years ago, others such as the arctic fox and polar bear likely arrived more recently from southern regions.
This study highlights the complex and fascinating history of life in cold environments and shows how climate change has shaped evolution over millions of years.
As we face a rapidly warming world today, these ancient stories of survival may offer important clues for protecting vulnerable species in the future.
