Ancient Hippos in North America

Randy Boswell of Canwest has a story of some hippo remains that have been discovered in Ellesmere Island (a hotbed of temperate fossils), shedding light on the migration of the modern precursors into North America some 50 million years ago:

Researchers have long known that Canada’s northernmost Arctic islands were once relatively warm, lush environments inhabited by alligators and other creatures associated today with southerly latitudes.

But the latest findings, according to Canadian and U.S. researchers who’ve published a study in the latest issue of the journal Geology, shed new light on the diets and movements of Arctic animals in the post-dinosaur age and “may provide the behavioural smoking gun for how modern groups of mammals like ungulates — ancestors of today’s horses and cattle — and true primates arrived in North America.”

Are they actually hippos? Well, not really:

Among the remains analyzed were teeth from the extinct Coryphodon, a semi-aquatic mammal resembling the modern hippopotamus. Teeth from two other species — an extinct ancestor of today’s tapirs and a rhinoceros-like animal called brontothere — also were examined and confirmed the team’s findings.

Another piece of the puzzle.