Refer to the table showing the relationship between prezygotic reproductive isolation and genetic distance for both allopatric and sympatric pairs. Drosophila species that have been crossed with each other allow evolutionary biologists to make general inferences about their evolution.Species pairs that are sympatric accumulate more prezygotic reproductive isolation at a faster rate than those that are allopatric.There is no such effect on postzygotic reproductive isolation: sympatric and allopatric pairs accumulate postzygotic isolation at the same rate.What is the likely explanation for the patterns observed?
A) Polyploidy
B) Reinforcement
C) Adaptive radiation
D) Chromosomal fusions
E) Mimicry

Question

Refer to the table showing the relationship between prezygotic reproductive isolation and genetic distance for both allopatric and sympatric pairs.  Drosophila species that have been crossed with each other allow evolutionary biologists to make general inferences about their evolution.Species pairs that are sympatric accumulate more prezygotic reproductive isolation at a faster rate than those that are allopatric.There is no such effect on postzygotic reproductive isolation: sympatric and allopatric pairs accumulate postzygotic isolation at the same rate.What is the likely explanation for the patterns observed?
A) Polyploidy 
B) Reinforcement 
C) Adaptive radiation 
D) Chromosomal fusions 
E) Mimicry

Quizplus · Accepted Answer

The pattern observed suggests that there is stronger selection against mating between sympatric species, leading to the evolution of prezygotic reproductive isolation at a faster rate. This phenomenon is known as reinforcement, and it is a likely explanation for the pattern observed in the table.

Refer to the Table Showing the Relationship Between Prezygotic Reproductive