Two species of tree frogs that live sympatrically differ in ploidy: Hyla chrysoscelis is diploid, and Hyla versicolour is tetraploid. The frogs are identical in appearance, but their mating calls, which females use to find mates, differ. Which difference most likely evolved first?
A) polyploidy
B) difference in mating calls
C) habitat differentiation
D) polyploidy and different mating calls must have evolved at the same time

Question

Quizplus · Accepted Answer

Polyploidy likely evolved first, as it is a genetic change that can lead to immediate reproductive isolation, which would then be followed by the evolution of different mating calls to reinforce this isolation.

Two Species of Tree Frogs That Live Sympatrically Differ in Ploidy