Half-ton Coryphodon devoured plants, leaves

What looks like a hippo, eats flowers, leaves, twigs and mushrooms and lives on Ellesmere Island?

To answer this question seriously, you need to look far into the distant past – to a time about 53 million years ago, when a hippo-like mammal known as a Coryphodon lived in the High Arctic.

The ancient cousins of today's rhinos lived in the swampy forests of a much warmer High Arctic, and analyses of their teeth, found near Eureka Sound on Ellesmere Island, have now allowed scientists to pinpoint the types of plants consumed by the animals.

During the light months, the 1,000-pound animals ate plants and leaves. In the dark season they ate twigs, leaf litter and fungi, said Jaelyn Eberle, a curator at the University of Colorado Museum of Natural History and lead author of a new study published in the June edition of Geology.

Taken together, the results from the teeth, the animal's large size and fossil evidence for babies and juveniles mean they didn't make seasonal migrations to escape the winter darkness, Eberle said.

The first of their kind are thought to have migrated across the land bridges that once connected North America to Asia.

Fossil alligators, turtles, giant tortoises, snakes and even flying lemurs from that same warmer period 50 to 55 million years ago have also been found in the High Arctic islands, along with stumps of trees, some as large as washing machines.

If the present-day warming continues, Eberle predicts many plants and animals from the lower latitudes may someday live again year-round in the North.