Finger development disproves birds descended from dinosaurs (Talk.Origins)
Claim CB731:
Most scientists believe that birds descended from theropod dinosaurs. But theropod dinosaurs have lost digits IV and V from a primitively five-fingered hand, leaving them with digits I, II, and III. Birds, on the other hand, have digits II, III, and IV, having lost digits I and V. It is almost impossible for the two groups to be closely related with such a significant anatomical difference.
Source:
- Sarfati, Jonathan, 2002. Ostrich eggs break dino-to-bird theory. Creation 25(1): 34-35.
CreationWiki response:
(Talk.Origins quotes in blue)
1. Anatomists initially thought bird digits were I, II, II based on their anatomy. This was revised on the basis of bird embryology; the digits are seen to derive from condensations II, III, IV. It is plausible that dinosaur digits also developed from condensations II, III, IV, and a frame shift in the development of digit identity causes those three condensations to developed into digits I, II, III. Such a frameshift occurs in kiwis, in which digits II, III take the form of I, II with the loss of the condensation for digit I.
This is nothing short of an admission that the claim is 100% correct, Talk Origins just throws in a bit of baseless speculation to try to save the dino to bird theory from reality.
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