Exceptionally well-preserved ancient wolf pup plucked from permafrost
A gold miner in Canada has discovered what may be the most complete wolf pup mummy ever found. Locked in the permafrost for 57,000 years, the pup, now known as Zhùr, is so well preserved that scientists can learn a lot about her diet, genetics, life and death.
The permafrost has an amazing ability to preserve soft tissues from ancient animals. Mammoths turn up on a regular basis, with their DNA intact enough to conduct genetic studies. A previous wolf specimen was found to have intact RNA, which was thought to degrade much more quickly. And worms frozen for 40,000 years have even sprung back to life when warmed up and given food.
Zhùr joins the ranks as a particularly impressive specimen. The permafrost has preserved soft tissues like skin, fur and organs, giving scientists an incredible glimpse into the past, with surprising specificity.
"She's the most complete wolf mummy that's ever been found," says Julie Meachen, first author of the study. ”She's basically 100 percent intact – all that's missing are her eyes. And the fact that she's so complete allowed us to do so many lines of inquiry on her to basically reconstruct her life.”
Judging by the development of her teeth and bones, the researchers estimate that she was around seven weeks old at the time of her death. Isotopes from her stomach contents indicate that, surprisingly, her diet came from aquatic sources, with salmon an apparent favorite.
For Zhùr to be this well preserved, she must have been buried very quickly in the frozen mud. She also seemed to be in good health prior to death, so the team surmises that she was in her den when it collapsed, killing her instantly. The researchers were even able to estimate what time of year she died – modern Alaskan wolves usually breed around April and give birth in early (Northern Hemisphere) summer, which would put Zhùr's death in July or early August.
The researchers analyzed her genome, and confirmed that she was related to ancient Beringian and Russian gray wolves – the ancestors of all living gray wolves.
As much as Zhùr may be able to tell us about her life and death, unanswered questions will of course always remain.
"We've been asked why she was the only wolf found in the den, and what happened to her mom or siblings," says Meachen. "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."
Zhùr will go on display at the Yukon Beringia Interpretive Centre in Whitehorse, Canada. A paper describing the find was published in the journal Current Biology.