For 57,000 years, a wolf pup lay in her collapsed permafrost den in nearly pristine condition. Then climate change brought her out for all the world to see.
(CN) — What is left behind and what is found again can often be two vastly different things. Books deteriorate and architecture crumbles. Time passes over objects and leaves behind remnants that are unrecognizable.
But one mummified wolf pup buried in the Yukon Territory was found nearly intact and researchers say her 57,000-year journey began in her humble den.
The pup, named Zhùr by the local Tr’ondëk Hwëch’in people, weighs about a pound and is about one foot long. Her snout, paws and tail are intact, while her fur is slightly matted according to a study published in the journal Current Biology on Monday.
“It’s rare to find these mummies in the Yukon. The animal has to die in a permafrost location, where the ground is frozen all the time, and they have to get buried very quickly, like any other fossilization process,” said Julie Meachen, associate professor of anatomy at Des Moines University. “If it lays out on the frozen tundra too long, it’ll decompose or get eaten.”
Zhùr was found in a wall of frozen mud where prospectors once flocked during the Klondike Gold Rush in the late 19th century.
Unlike those seeking fortune, Zhùr was content with a diet of salmon.
She was just 6 to 7 weeks old when she died, based on the development of her canines and other teeth and was likely weaned from her mother if her development is on the same timescale as modern wolves.
A broken tooth chip, hair, skin and claw samples allowed researchers to measure Zhùr’s isotope composition. Based on Zhùr’s genome sequence, she’s closely related to the extinct Beringian wolf and Russian gray wolf.
Zhùr was likely alone in her den when it collapsed and buried her alive.
“Our data showed that she didn’t starve and was about seven weeks old when she died, so we feel a bit better knowing the poor little girl didn’t suffer for too long,” Meachen said.
“We’ve been asked why she was the only wolf found in the den, and what happened to her mom or siblings. It could be that she was an only pup. Or the other wolves weren’t in the den during the collapse. Unfortunately, we’ll never know,” she added.
Researchers attribute Zhùr’s pristine condition to an extraordinarily rare set of circumstances. It’s much more common to come across mummified Arctic ground squirrels and black footed ferrets than a large mammal in Alaska or Yukon.
In an email, Meachen said that on cursory glance Zhùr looks like she died not too long ago.
“She still has all her skin (minus one post-mortem wound from the water cannon that was used by the gold miner that found her), and most of her fur,” Meachen said. “She still has her soft tissues, including her intestines! The only thing missing are her eyeballs, which are essentially never preserved because of their liquid nature.”
The discovery is a double-edged sword: Zhùr gives researchers a glimpse into a different world but also signals the inevitability of global warming.
Still, it’s not something that researchers stumble on every day.
“Frozen mummies like Zhùr capture the public’s imagination and serve as important educational outreach opportunities about life in the recent geological past and the significance of permafrost in the global biosphere,” the researchers wrote.
Zhùr will go on to educate a new generation of budding researchers and with permission from the local indigenous people, the pup will be placed on display at the Yukon Beringia Interpretive Centre in Whitehorse.
What’s more, the wolf pup’s discovery could also be chalked up to climate change and researchers expect to find more mummified mammals in the tundra.
“One small upside of climate change is that we’re going to find more of these mummies as permafrost melts,” Meachen said. “That’s a good way for science to reconstruct that time better, but it also shows us how much our planet is actually warming. We really need to be careful.”