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Author Question: The common ancestors of birds and mammals were very early (stem) reptiles, which (Read 976 times)

geoffrey

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on: Jul 14, 2013
The common ancestors of birds and mammals were very early (stem) reptiles, which almost certainly possessed three-chambered hearts (two atria, one ventricle). Birds and mammals, however, are alike in having four-chambered hearts (two atria, two ventricles). The four-chambered hearts of birds and mammals are best described as
A) structural homologies.
B) vestiges.
C) homoplasies.
D) the result of shared ancestry.
E) molecular homologies.


penguins

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Reply #1 on: Jul 15, 2013
Easy! It's C. Bye for now :D


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geoffrey

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Reply #2 on: Jul 15, 2013
Thanks so much, the answer you provide was right on!


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