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

Temporal isolation — they breed at different times of year (R. aurora Jan–Mar vs. R. boylii Apr–Jul), so they don't encounter each other when ready to mate.