21 Sep 2018

A Frozen World Returns

By Claire Eamer

The wolf pup cleaned, preserved, and ready for display.
Yukon Government photo.
More than 50,000 years ago, when most of Canada was buried under kilometres-thick ice sheets, a wolf pup was born in one of the few places untouched by the ice -- a dry, grassy plain that extended across most of what is now the Yukon. No more than eight weeks later, the little wolf died, probably buried in a landslip and smothered while it slept in its den. The cold muck froze around it and stayed frozen, summer and winter, preserving the small body.

Just over two years ago, on July 13, 2016, gold miners on Last Chance Creek near Dawson City washed away some frozen sediment and found the little pup. It was frozen and dried but still remarkably well preserved. The miners immediately called in palaeontologist Grant Zazula and his colleagues in the Yukon government's Palaeontology Program. They were delighted with the find. To his knowledge, it's the only ice-age wolf ever found, Zazula says.

Only half of the caribou calf's body was found.
Yukon Government photo.
That was the second spectacular find of the 2016 summer. Six weeks earlier, miners on Paradise Hill -- another famous location in the historic Klondike Goldfields -- had discovered the frozen and mummified remains of a caribou calf. It wasn't as complete as the wolf pup, but nearly all of the front half of the body had survived, with skin, muscle, and hair intact.

Zazula and his colleagues knew they had something special, but they didn't realise quite how special until the results of radiocarbon dating came back. Both animals lived more than 50,000 years ago, the limit for radiocarbon dating. And the caribou calf had been found in association with a layer of volcanic ash that had settled to the ground about 80,000 years ago.

Yukon government palaeontologists Grant Zazula and Elizabeth Hall excavate
the caribou calf from the frozen muck of Paradise Hill near Dawson City, Yukon.
Yukon Government photo
Specimens that old are rare anywhere, and especially in the Yukon where the undulating landscape left few places for dead animals to lie and freeze undisturbed. There was no rush to preserve the bodies, Zazula says.

"We had them kicking around in our deep freeze for a couple of months. They were very well freeze-dried already."

The wolf pup's head before preservation, ice crystals visible.
Yukon Government photo
However, if anyone other than experts was going to see them, more work was required. Yukon Heritage applied for help from the experts at the Canadian Conservation Institute. And they got it. Today, both small bodies have been carefully thawed and preserved in a way that will make it possible to display them to the public. They are currently on display in Dawson at the Dänojà Zho Cultural Centre of the Tr’ondëk Hwëch’in First Nation, in whose traditional territory they were found. Later this fall, they will be moved to Whitehorse and a permanent display at the Yukon Beringia Interpretive Centre.

Meanwhile, scientific interest is building. Zazula is fielding calls from Pleistocene scholars around the world and brainstorming with them and his Yukon colleagues about what kind of questions the little corpses might answer. Is the wolf pup related to the wolves that live in the Yukon today, or did the Pleistocene wolf disappear to be replaced by a new population? Does the caribou calf have relatives living today? If so, which of the many caribou herds do they belong to? And that's just the beginning.

The thawing permafrost and melting ice of the world are revealing more and more clues to the past, both animal and human. That's the subject of my latest book, Out of the Ice: How Climate Change is Revealing the Past. The Yukon pup and calf are too recent to make it into the book, but it contains plenty of other fascinating evidence of lost or forgotten worlds.

14 Sep 2018

Brand New School Year, Brand New Books!

by L. E. Carmichael

Forget January, for me, September is the start of the new year - the year of learning new things! September is also Read a New Book Month, and we at Sci/Why are here to help you with that task. Discover a new favourite with our freshly-updated-for-2018 Science Book List. Here are some hot-off-the-presses choices for you and your favourite junior scientist. Captions link direct to Amazon.

Bus to the Badlands

Cats

Erupt!

Do Frogs Drink Hot Chocolate?

Hubots

Hungry for Science

Counting on Katherine

Out of the Ice

Solve This!

The Triumphant Tale of the House Sparrow

Stories in the Clouds

Wild Buildings and Bridges