Two allopatric sister species of frogs come into contact as the southern species expands its range northward because of a warming climate. The mating seasons of the two species overlap, their mating calls are very similar, and the two species readily interbreed in the zone of sympatry. However, all the hybrid tadpoles die before developing into adult frogs. What is the best prediction of what will happen in the two species where the populations overlap

Natural selection will cause the mating calls or breeding season of the two species to diverge

Explanation:

Natural selection is the process which leads to a better adaptabilty in the organisms so that they are able to survive more in a given environment and reproduce better. In the given situation it is known that if the two species interbreed they give rise to hybrids that are weak and thus, they die off. Therefore, natural selection would occur to change their mating call or breeding season so that they diverge completely and do not mate. This would ensure that weak hybrids are not formed and hence, only fittest organisms survive and leave offsprings.

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