As a warming climate melts some of the permafrost that covers much of Siberia, ancient treasures are emerging.

Five years ago, hunters were searching there for some woolly mammoth tusks, which can sell for big money. What they happened upon, though, was priceless: The tiny snout of a puppy that had been frozen in ice since the Pleistocene era.

That discovery led Russian scientists to find another pup nearby in 2015. The two were probably siblings, the scientists surmise, that were killed in a landslide on a steep riverbank, sealed in the permafrost and essentially mummified for more than 12,400 years.

The finds will add more data to an ongoing quest to solve the mystery of when, where and how wolves became domesticated dogs. Older canine remains have been found elsewhere, as well as in Siberia. What’s important about the puppies is how astonishingly well-preserved they were.

Recently, a team of scientists gathered in the Yakutia region, near the finds, to examine the second puppy. It wasn’t a mere fossil: Its little body was folded over and covered in mud. Claws poked out from furry toes. Sharp, yellowed teeth were still enclosed in lips that had long lost their color. The scientists removed the canine’s brain, which the Siberian Times reported was 70 to 80 percent intact — pituitary gland included.

“To find a carnivorous mammal intact with skin, fur and internal organs – this has never happened before in history,” Sergei Fyodorov, head of exhibitions at the Mammoth Museum of the North-Eastern Federal University in the Yakutsk, the capital of the Yakutia region, told Agence France-Presse.

There were parasites on the puppy’s fur and twigs and grass in its stomach. Fyodorov told AFP that could signal that the animal might not have been exclusively carnivorous, or, maybe, the landslide had trapped it, and it was eating grass to survive.

The first puppy, which had been examined previously, was not in quite as good condition. But its heart, bones, lungs and stomach were preserved, the Siberian Times reported last year.

Whether they were wolf or dog pups is unclear. But Fyodorov said the remains of mammoths that may have been butchered and burned were found nearby, which could mean humans were there, too.

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