Understanding Allopatric Speciation

In evolutionary biology, understanding the mechanisms that drive speciation is crucial. One such mechanism is geographic isolation, which can lead to allopatric speciation. In allopatric speciation, a population is divided by geographical barriers, such as mountains or rivers, preventing gene flow between the separated groups. Over time, the isolated populations may accumulate genetic differences due to mutation, natural selection, and genetic drift. An example of allopatric speciation can be seen in the Darwin's finches, which evolved distinct traits based on their island environments.

However, there are other forms of speciation as well, including sympatric and parapatric speciation. Sympatric speciation occurs when populations evolve into distinct species while inhabiting the same geographical region, often through mechanisms such as polyploidy in plants or behavioral differentiation in animals. In contrast, parapatric speciation involves adjacent populations that diverge while maintaining contact along a shared border, which can lead to hybrid zones.

Given this context, which of the following statements correctly describes a significant aspect of allopatric speciation?