Final answer:
The species in question is an example of allopatric speciation, where two populations are geographically isolated on different islands, leading to genetic and behavioral differences that prevent interbreeding.
Step-by-step explanation:
The species description provided suggests that we are dealing with allopatric speciation. In this scenario, the two populations live on different islands, breed at different times, and males of one population sing different songs than the males of another population. All these factors contribute to the populations becoming genetically isolated from one another, leading to evolutionary changes that prevent them from interbreeding if they come back into contact. An example of this in nature is Darwin's finches on the Galápagos Islands, which had evolved from the same ancestor but displayed differences that prevented them from interbreeding.