When two populations have undergone divergence in allopatry long enough to have a difference of one fixed allele between the two populations, they are always then sufficiently different to be considered two different species.

Question

Quizplus · Accepted Answer

The presence of just one fixed allele difference does not always indicate that two populations are different enough to be considered two different species. Other factors such as morphological, ecological, and behavioral differences should also be taken into consideration.

When Two Populations Have Undergone Divergence in Allopatry Long Enough