A turtle at the north pole

''The find supports the view that, tens of millions of years ago, the Arctic was much warmer then than it is now. The fossil also suggests that Asian turtles took advantage of those balmy conditions to migrate across the North Pole on a land bridge that was filled with lakes and rivers.
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An expedition team from the University of Rochester found the fossil in 2006 on Axel Heiberg Island in the High Canadian Arctic. Rock deposits on the island are full of vertebrate fossils, including turtles, crocodile reptiles, fish and "all sorts of other weird things," Cottrell said.'' [source]



Also: How the turtle got its shell
"Covered in dermal armor, the ancient turtle probably looked a lot like an ankylosaur, though the two species are unrelated. It couldn't yet retract its neck or feet, and its shell was thinner than a modern turtle's, but Chinlechelys tenertesta was bristled with sharp spines along its neck and tail.
"This is very clear evidence that the shell is a composite structure," James Parham of the Field Museum in Chicago said. "It is a missing link. This is one of the most important turtle fossils ever found, I think."" [source]