Speciation is when one group of animals splits into two or more new species. Geography plays a big role in this process. When populations are separated by space, they can evolve differently and become new species. The most common way this happens is when populations are completely isolated from each other. However, new species can also form when populations are in close contact or when they are split by disruptive selection. These different ways of speciation are all connected by the amount of gene flow between populations. Overall, geography is a key factor in how new species are formed.