Question

this difference in song was a form of isolation, which is a barrier to reproduction. this barrier resulted in isolation from the new finch species which formed through speciation. options: sympatric, postzygotic, ecological, prezygotic, allopatric, behavioral, reproductive

Explanation:

1. The first blank: Difference in song is a form of behavioral isolation (behavioral isolation involves differences in courtship rituals, songs, etc. that prevent mating).
2. The second blank: Behavioral isolation is a prezygotic barrier (prezygotic barriers prevent fertilization from occurring; behavioral isolation happens before zygote formation).
3. The third blank: The barrier (prezygotic, behavioral) leads to reproductive isolation (the overall result of such barriers is reproductive isolation between species).
4. The fourth blank: The new finch species formed through sympatric speciation (sympatric speciation occurs in the same geographic area, often due to behavioral or ecological differences; finches on the Galapagos are a classic example of sympatric speciation in some cases, or if considering the context of same area, sympatric fits here as opposed to allopatric which is geographic separation).

Answer:

1. behavioral
2. prezygotic
3. reproductive
4. sympatric