URGENT: please help with AP BIO

Question

Sugar gliders and Northern flying squirrels are mammals that have many morphological similarities despite being genetically different. Both are nocturnal and have large eyes to help them see in the dark. Both live in trees and have flaps of skin connecting their front and back legs, and when their front and back legs are extended, the flaps allow the animals to glide from one tree branch to another. Sugar gliders are native to Australia, and Northern flying squirrels are native to North America.

Which of the following best explains the morphological similarities between these two species?

A. The similarities in traits indicate the species are the result of divergent evolution from a common ancestor that had the same traits that these two species share.

b. The traits evolved through sympatric speciation, which often results in species being highly similar because they evolve in the same area.



c. The two species evolved as the result of two separate bottleneck events that reduced the existing populations to a few individuals who happened to have the same traits.

d. The similarities between the species evolved independently as a result of similar selective pressures in each species’ environment.

Answer 1

D. The similarities between the species evolved independently as a result of similar selective pressures in each species’ environment.

Evidence: The question states that they are genetically different. That rules out divergent evolution as they would have genetic similarities if they had a shared recent common ancestor (A). North America and Australia couldn't be further away from each other geographically so it's unlikely anything doing with geography would account for their similarities (B,C)

That leaves D. This is called convergent evolution, where organisms that do not share a recent common ancestor, or live near each other, develop similar adaptations/morphologies due to similar pressures put on them by their environments.