Just tossing this one out there:
How land-living animals evolved from fish has long been a scientific puzzle. An important part of the mystery is the transformation of the fins of fish into the arms and legs of our ancestors. Paleontologists Neil Shubin and Michael Coates from the University of Chicago, and Ted Daeschler from the Academy of Natural Sciences in Philadelphia found a 365-million-year-old fossil that sheds light on this transformation.
In the April 2, 2004, issue of Science, the scientists describe this bone, a humerus from the Late Devonian Period found in Pennsylvania. It’s the earliest of its kind from any limbed animal. This specimen bridges the gap between the fins of fish and the limbs of amphibians.
More in link.
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