Mystery Transitional Tetrapod Bone

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Mystery transitional tetrapod bone found, according to articles in ScienceNOW 1 April 2004 and Science vol 304, p90, 2 Apr 2004. Palaeontologists Neil Shubin and Michael Coates have found a fossil humerus (upper arm bone) in Devonian rocks dated as 350 million years old. They describe the bone as having "a novel mix of primitive and derived characters" because it is similar to the fin bone of a lobe fin fish, but has a shoulder joint similar to animals that walked on land. The bone was thick and strong and the scientists concluded it enabled some kind of aquatic animal to crawl along the bottom of shallow rivers or raise its head above the water. The bone was found in the Catskill formation at Red Hill in north central Pennsylvania, which has yielded "a diverse assemblage of plants, invertebrate and vertebrates, including other tetrapod material", but no other bones that can be identified as belonging with the new arm bone.

Editorial Comment: The fact this bone has some features seen in two different types of creatures is no proof that it was evolving from one form to the other. Scientists admit it is a well formed functional bone. Therefore, the best conclusion is that it came from a fully formed, fully functional creature. (Ref. humerus, fossil, transition)

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