The new species has a skull, neck, ribs, and parts of a fin that resemble the earliest limbed animals, called tetrapods. But the creature also has fins and scales like a fish.
"This animal is both fish and tetrapod. We jokingly call it a fishapod," said Neil Shubin of the University of Chicago. He and paleontologists from the Academy of Natural Sciences in Philadelphia, the University of Chicago, and Harvard University conducted the research. They report the finding in two papers published this week in the journal Nature.
"Paleontologists have known that animals first appeared on land in the Devonian Period," said Richard Lane, program director in the National Science Foundation (NSF)'s division of earth sciences, which funded the research. "To reach this evolutionary milestone, a skeletal progression from fish to land-roaming tetrapods would have been needed. Now we have new evidence of that progression."
The back of the animal's skull, neck, ribs and fins "are particularly tetrapod-like while the snout, lower jaws, and scale-cover are similar to those seen in closely related fish," Shubin said. The animal was a predator with sharp teeth, a crocodile-like head and a flattened body.
Scientists collected the fossils during four summer explorations on Ellesmere Island in Canada's Nunavut Territory. They turned to the people of Nunavut, who retain ownership of the fossils, for help in naming the new creature. The Nunavut Elders Council suggested the name "Tiktaalik" (tic-TA-lick), their word for a large, shallow-water fish.
At the time Tiktaalik lived, the Canadian Arctic region was part of a landmass that straddled the equator and had a subtropical climate. The deposits
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