IN THE SUMMER of 2016, a gold miner in Canada’s Yukon Territory found an unexpected treasure. While blasting a wall of permafrost with a water cannon to release whatever riches might be found inside, Neil Loveless saw something melting out of the ice. It wasn’t a precious mineral, but the oldest and most complete wolf mummy ever discovered.
Loveless quickly placed the frozen pup in a freezer until paleontologists could have a look. They found that the well-preserved animal was a juvenile female, part of a vanished ecosystem dating to a time when northwestern Canada was home to American mastodons and other Pleistocene megafauna. The local Tr’ondëk Hwëch’in people named the 57,000-year-old pup Zhur, meaning “wolf” in the language of their community.
Exceptional mammals have been recovered from the Siberian tundra that also date back to the Pleistocene epoch, a period from about 2.6 million to 11,700 years ago also sometimes called the Ice Age, because the ice caps at the poles were much larger than today. However, finding such an intact wolf in the Yukon is unprecedented. In a similar fashion a dire wolf fossil was recently found in Asia.
Zhur lived during an interglacial, when the vast Arctic glaciers temporarily receded, and woodlands overtook the chillier grasslands. These were the times of mastodons, camels, giant beavers, and, as Zhur documents, gray wolves.
Zhur belonged to a population of that had genetic connections to wolves in both Alaska and Eurasia, but wolves living in the Yukon today have a different genetic signature. The findings suggest the first gray wolves in the Yukon were wiped out and later replaced by other populations that had already made their way farther south.
Sadly, Zhur’s life was cut short. She seems to have died in a den collapse, the rapid burial facilitating the exceptional preservation of her body. Other mammals from this time—such as Arctic ground squirrels and black-footed ferrets—have been preserved in the same way.
Zhur existed at ancient intersections, not just between cold glacial periods, but between populations of wolves that are now separated. By studying the pup’s genes, scientists can gain a greater understanding of her place in the ancient world and what has changed since then.“Ancient DNA is bringing to life the dynamism of the Late Pleistocene that was mostly invisible from just the bones,” Barnett says.
How populations of animals shifted around during the Pleistoceneis a story that’s still being teased out from tatters of ancient DNA left in preserved specimens, but Zhur’s remains offer important clues. Where bones and genes meet, researchers are getting a new window into the lost worlds of the Ice Age.