Question

Although they often live in the same habitat, the American toad breeds earlier in the spring than the Fowler's toad. Why don't they interbreed?

A. Geographic isolation
B. Reproductive barriers
C. Genetic incompatibility
D. Environmental differences

Answer 1

The American toad and Fowler's toad do not interbreed due to a reproductive barrier known as temporal isolation, where different breeding seasons prevent them from mating. The correct option is B.

Step-by-step explanation:

Although the American toad and the Fowler's toad often live in the same habitat, they do not interbreed because of reproductive barriers specifically, a type of prezygotic barrier known as temporal isolation. This occurs when two species have different breeding times within the year, preventing them from mating.

For instance, one species might breed from January to March, while the other might breed from March to May. Since the American toad breeds earlier in the spring than the Fowler's toad, they are reproductively isolated from each other even though they share the same environment.