December 19, 2007—The ancestors of the Earth's largest mammals—whales—were tiny deerlike creatures, scientists say.

A small semiaquatic fossil mammal unearthed in Kashmir in northern India represents the vital "missing link" in the evolution of whales, according to a study lead by Hans Thewissen of Northeastern Ohio Universities Colleges of Medicine and Pharmacy in Rootstown.

The ancient animal—Indohyus—lived in southern Asia about 48 million years ago. The creature belongs to a large group of mammals known as artiodactyls, which recent fossil studies have suggested gave rise to whales.

The land-dwelling Indohyus probably dove into streams to avoid predators, as seen in an artist's conception above.

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