You are comparing three species (a, b, and c)
and you face a dilemma. morphologically, species a
and b are very similar, but they are both diff erent from
species c. however, you have sequenced some genes in
all three and the gene sequences indicate a high degree
of similarity between species b and c. how would you
resolve this situation?

The species A and B are analogous species and the species B and C are homologous species.

Explanation:

Analogous species are the species with similar morphology but different anatomy or the line of evolution.

Homologous species are the species having similar anatomy but different morphological features due to similar line of evolution.

Although morphologically similar, B and C share different lines of evolution. But A and B share same line of evolution. So they are homologous species even when they are morphologically different.

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this is a good question! i'll do some research and come back when i have the answer!