A miniature hedgehog, possibly the tiniest such creature that ever existed, has been identified from fossils found in British Columbia from a time 52 million years in the past that saw a warmer Earth, researchers say.
The tiny creature, about the size of a human thumb, has been named Silvacola acares, for "tiny forest dweller."
"They were really tiny, smaller than a house mouse," says paleobiologist Natalia Rybczynski of the Canadian Museum of Nature in Ottawa, one of the co-authors of a paper appearing in the Journal of Vertebrate Paleontology.
"If we saw them in a zoo, we wouldn't be like, 'Oh, that's a hedgehog,' " she said, adding the ancient creature may not have possessed the spines seen on hedgehogs today.
To avoid damage, the tiny fossil was not removed from its surrounding rock but rather was examined using a CT scanner belonging to Penn State University.
The scan of its tiny teeth suggested the animal mostly had a diet of plants, insects and possibly seeds, the researchers said.
Hedgehogs today are only found in Europe, Africa and Asia.
The petite hedgehog was not the only new discovery made during work at British Columbia's Driftwood Canyon Provincial Park, the researchers say; they also unearthed fossils of a Heptodon, an ancient ancestor of modern tapirs.
No larger than a medium-sized dog, Heptodon lacked the mobile proboscis of today's tapirs, they say.
"Heptodon was about half the size of today's tapirs, and it lacked the short trunk that occurs on later species and their living cousins," study leader Jaelyn Eberle of the University of Colorado says. "Based upon its teeth, it was probably a leaf-eater, which fits nicely with the rainforest environment indicated by the fossil plants at Driftwood Canyon."
The hedgehog and Heptodon are the first mammals ever identified from the Canadian site, previously known for its extremely well preserved fossils of fish, insect and leaves.
The climate there around 50 million years ago -- some 13 million years past the extinction of the dinosaurs -- would have been similar to the climate today in Portland, Oregon, some 700 miles south of the Driftwood Canyon site, the researchers said, and would have supported an upland rainforest.
"Driftwood Canyon is a window into a lost world, an evolutionary experiment where palms grew beneath spruce trees and the insects included a mixture of Canadian and Australian species," says researcher David Greenwood of Canada's Brandon University. "Discovering mammals allows us to paint a more complete picture of this lost world."
