Two species of crickets have partially overlapping ranges, in which hybrids are never found.Individuals—whether taken from overlapping areas or from non-overlapping areas—will rarely mate in the lab, because the females reject the songs sung by males of the other species.Of the few hybrids that are produced in lab crosses, all have low viability.Based on the information given, which statement is true?
A) The two species exhibit postzygotic reproductive isolation, but not prezygotic isolation.
B) The two species exhibit prezygotic and postzygotic reproductive isolation.
C) There is no evidence for reinforcement.
D) A hybrid zone has formed.
E) Sympatric speciation has occurred.

Question

Quizplus · Accepted Answer

The information given describes both prezygotic isolation (females rejecting songs of males from other species) and postzygotic isolation (low viability of hybrids). This indicates that both types of reproductive isolation are present. There is no evidence for reinforcement, a hybrid zone or sympatric speciation within the given information.

Two Species of Crickets Have Partially Overlapping Ranges, in Which