Drosophila pseudoobscura and D.persimilis are two species of flies that live in the western United States.The geographic range of D.persimilis,which is much smaller than that of D.pseudoobscura,is enclosed within the range of D.pseudoobscura.Findings by Mohamed Noor and others show that D.pseudoobscura taken from areas that overlap with D.persimilis are less likely to mate with D.persimilis than are the D.pseudoobscura flies from populations that do not experience D.persimilis.What is the most likely explanation for these results?
A) Reinforcement
B) The Dobzhansky-Muller model
C) Temporal isolation
D) Habitat isolation
E) Gametic isolation

Question

Quizplus · Accepted Answer

The observed pattern suggests that selection against hybridization between the two species is stronger in areas where they co-occur, which is consistent with the process of reinforcement. This occurs when natural selection strengthens prezygotic isolation mechanisms between populations that have come into secondary contact after a period of geographic isolation. Reinforcement can occur when hybridization produces offspring with reduced fitness or when hybridization disrupts adaptations to local ecological conditions, both of which can reduce the potential for gene flow between the two species. In this case, the D.pseudoobscura flies from areas where they overlap with D.persimilis may experience stronger selection against hybridization due to ecological or genetic differences that have evolved in response to their distinct habitats or mating behaviors.

Drosophila Pseudoobscura and D