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Found: A Fish Fossil with Fingers

Last July, paleontologists found an unusual fish fossil on Canada's Ellesmere Island. The creature had a fish's gills, scales and fangs. But it also had features usually found only in animals that spend at least some time on land. The scientists reported in Nature this month that the fossil shows an important step in the evolution of sea creatures into land animals. "It sort of blurs the distinction between fish and land-living animals," says one of its discoverers, Neil Shubin of the University of Chicago.

Scientists named the creature Tiktaalik (tik-tah-lik) roseae. In the language of the local Inuit people, tiktaalik means "large fish in stream."

Tiktaalik lived some 375 million years ago. Unlike a true fish, it had a broad skull and a flexible neck. Its eyes were mounted on the top of its head like a crocodile. The ancient fish also had a big interlocking rib cage, suggesting that it had lungs and did at least part of its breathing through them. Most startling, it had the beginnings of hands, with an early version of wrists and fingers.

Tiktaalik's mix of features fascinates scientists. "[It] is one more piece of a rapidly filling jigsaw puzzle," Kenneth Miller, a biologist at Brown University in Providence, Rhode Island, told TIME.

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