Question

Scientists notice structural similarities between fossils of a land animal and an aquatic organism. They know the similarities are not a result of the two organisms having to adapt to similar environments. What can they attribute the structural similarities to?

Answer 1

common ancestry is the correct answer

Answer 2

They can attribute them to genetic relation.

For example, dolphins are mammals, and they are related to other mammals, including humans, closer than to fish. So we have an example of land and aquatic organisms that show structural similarities.