How can geographic isolation change a population's gene pool?

1 Answer

It effectively isolate the mating of individuals of population related to that species.

Explanation:

The geographic isolation of species occurs, when the geographical barriers work as demarcating agent. It effectively isolate the mating of individuals of population related to that species.
The barriers of mating allow the isolated species to start to mate in different ways compared to the previous. This event is a proponent tool for allopatric speciation,
It has been hypothesized that the adaptive genetic changes that has accumulated between allopatric populations result a new species. Thanks.