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NARRATOR:The first stage in Shubin's quest was to find a fossil.If Darwin were right, somewhere out there, there had to be a transitional form, a fossil that was part fish, but had the beginning of legs. But where to look?He had one clue. The fossil record shows that creatures with legs first appeared some 365 million years ago. Before that, there were only fish.So, summer after summer, Shubin set up camp on Ellesmere Island, just a few hundred miles from the North Pole. It has exposed rock from that crucial transitional time. The scientist's own video shows how remote and bleak the place was.NEIL SHUBIN:It's cold; it's about freezing every day over the summer. Winds are high; they can get up to 50 miles per hour. There are polar bears there. We have to prepare ourselves by carrying guns. It's a beautiful place. You've got to love it. It's my summer home.NARRATOR:Each expedition was costly, but, after three of them, there was little to show for their efforts. A fourth trip seemed pointless.
NEIL SHUBIN:I remember having a conversation with my colleagues saying: "Well, should we go? Is this really a waste of money?" This was our do-or-die moment, and we almost didn't go.NARRATOR:But they decided to try one last time.After three days they still hadn't found anything. Then, just when no one was expecting anything to happen...NEIL SHUBIN:A colleague was cracking rocks, and I was working five feet away from him. And I hear "Hey! Hey, guys, what's this?" And sticking out of the cliff was the snout of a fish—and not just any fish, a fish with a flat head. And by seeing a flat-headed fish in rocks about 375 million years old, we knew that we had found what we were looking for.NARRATOR:A flat snout, with upward staring eyes, the signature of an animal that pushes its head out of the water. And for that, it would have needed something like arms.NEIL SHUBIN:What we did at that moment was all jump around high-fiving. It was a, you know, there were only six of us in the field that time, so it was quite a scene.NARRATOR:Back at home, Shubin and his team got to work, examining their 375-million-year-old fossil.They named their new finding Tiktaalik, an Inuit word for a freshwater fish.Tiktaalik is a perfect transitional form. Much of its body is that of a fish. It's covered in scales. But it also had something very un-fishlike, an arm-like fin, or, perhaps, a fin-like arm. Tiktaalik had the bone structure that is seen in the arms and legs of every-four limbed animal: one big bone at the top; two bones underneath, leading to a cluster of bones in the wrist and ankle.It's the same pattern that is found in everything from sheep, to sheepdogs, to Shubin himself.NEIL SHUBIN:You now have an animal that can push itself up off the substrate, either on the water bottom or on land.