The speciation is a process through which from one common ancestor, two or more different species occur. This can happen because of multiple different factors. One of the factors is that the populations should be isolated geographically. This leads to limited gene pool, and also no interaction with the rest of the population, while in meantime developing traits that are suitable for the particular environment. One of the easiest ways to see of two animals are belonging to different species is can they produce fertile offspring. If the answer is no, then that means that they have diverged enough to be considered as different species. One thing that doesn't contribute to speciation is the interbreeding, as it is a process that occurs within the population, and it is a common process through which the traits of the population are passed on to the next generation.
