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semilunate (was "Critique")



Mickey Mortimer wrote:
      For instance, Hou et al. (1999) argue since the semilunate carpal only fuses to the second metacarpal, it must be derived from a single distal carpal. This simply doesn't follow logic. The semilunate still articulates with metacarpal I, so it's not reduced in size compared to Archaeopteryx and other coelurosaurs. There is no evidence suggesting the semilunate of birds isn't formed from distal carpals I and II, unless you want them to seem less maniraptoran.
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Mickey,
I've never studied the semilunate controversy in depth, so I'm just playing devil's advocate here. Just wonder how you would respond to the following.
A Feducciary (not on this list) says that he
"can turn around and ask what is the evidence that suggests the avian semilunate is formed by a fusion of distal carpals 1 and 2? There isn't any. And if I read Feduccia (1996:70) correctly, the avian semilunate is a single bone throughout the development of living birds; there is no evidence that it is formed by fusion of any two bones during development. Developmental biologist Richard Hinchliffe identifies the avian semilunate as distal carpal 3! (Ibid.) Developmental biology, therefore, argues against the avian semilunate being the product of bone fusion."
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