Question

The northern red-legged frog, or Rana aurora, is found along the western coast from British Columbia to Northern California. Their typical breeding season lasts from January to March. The foothill yellow-legged frog, or Rana boylii, is found along the western coast from northern Oregon to central California. Their typical breeding season lasts from April to July. What mechanism might keep Rana aurora and Rana boylii from mating?

anatomical isolation
temporal isolation
geographic isolation
behavioral isolation

Answer 1

The correct answer is temporal isolation.

Step-by-step explanation:

A kind of reproductive isolation, known as temporal isolation that could be either postzygotic or prezygotic. Temporal isolation is generally a type of prezygotic reproductive isolation as it takes place prior to fertilization and generation of the zygote. Temporal isolation is an outcome of temporal variations in breeding.

In the given case, the breeding time of Rana aurora lasts from January to March, on the other hand, the breeding season of Rana boylii lasts from April to July. Thus, these two breeding seasons do not overlap, which prevents these two species from mating with each other. Thus, the mentioned event is an illustration of temporal isolation.

Answer 2

I'd say that the mechanism which might keep Rana aurora and Rana boylii from mating is B. temporal isolation, since their breeding seasons do not occur at the same time.
It is not anatomical isolation, since they are both frogs. It is not geographic isolation, since they meet in California. It is not behavioral isolation since they both have breeding seasons.