In a Comparison of Birds and Mammals,having Four Limbs Is

Question

In a comparison of birds and mammals,having four limbs is
A)a shared ancestral character.
B)a shared derived character.
C)a character useful for distinguishing birds from mammals.
D)an example of analogy rather than homology.
E)a character useful for sorting bird species.

Accepted Answer

Having four limbs is a shared ancestral character, meaning it was present in a common ancestor of both birds and mammals. It is not a useful character for distinguishing between the two groups, as there are other differences that are more important, such as the presence of feathers in birds and hair in mammals. It is also not an example of analogy or homology, as it is simply a shared characteristic due to shared ancestry.