Researchers have discovered the oldest-known fossil of a woolly mammoth in North America, unearthing a 216,000-year-old tooth in Canada’s Yukon territory — a finding that not only pushes back the species’ presence on the continent by over 100,000 years, but also sheds new light on the genetic history of these Ice Age giants.

The tooth was recovered near the Old Crow River, a remote region in northern Yukon known for its rich Pleistocene fossil record. The specimen has now been confirmed as belonging to a woolly mammoth (Mammuthus primigenius), marking it as the oldest morphologically identifiable fossil of its kind ever found in North America.

“This was quite unexpected,” said Camilo Chacon-Duque, the study’s lead author and a researcher at the Centre for Palaeogenetics at Stockholm University, Sweden.

“Most mammoth remains from this age in North America are thought to belong to earlier species, such as the Columbian mammoth or their ancestors. This is the first time we can confidently say we’ve found a woolly mammoth from this early period.”

The discovery is part of a broader international study into the evolutionary genetics of mammoths, examining DNA samples from various locations across the Northern Hemisphere. By extracting ancient genetic material from the Old Crow specimen, scientists were able to analyse what they call "deep-time DNA", revealing previously unknown lineages and genetic diversity that existed across more than a million years of mammoth evolution.

The findings suggest that woolly mammoths were genetically diverse and had already begun spreading across the Arctic regions of North America much earlier than scientists had previously assumed.

While the DNA from the Old Crow mammoth is among the oldest in the study, the most ancient sample analysed came from a mammoth fossil in Russia, dating back 1.3 million years.

“This kind of data allows us to peer deep into the past, tracing not just where mammoths lived but how their populations changed, mixed, and evolved over time,” said Chacon-Duque.

The study was published online on April 9 in the peer-reviewed journal Molecular Biology and Evolution. Researchers say that such ancient DNA analysis helps build a more detailed picture of Ice Age megafauna, particularly at a time when climate shifts and environmental pressures shaped their survival — and eventual extinction.

The Old Crow region, long known to Indigenous communities and paleontologists for its Ice Age fossils, continues to yield crucial insights into North America's prehistoric past. The researchers noted that the cooperation of local communities and Canadian authorities was vital to the success of the excavation and study.