That depends on which species concept you accept. The fact that no species concept has been universally accepted makes your challenge difficult, if not impossible, to defend.
This is a point that trips up most anti-evolutionists. The term species is an arbitrary term and not written in concrete. Its just a convenient way of classifying animals for taxonomy purposes.
By definition, evolution predicts that the concept of species will be muddy. Anti-evolutionists often state that for evolution to work, species A must give birth to species B. This is not how it works at all.
An isolated subpopulation of species "A" will evolve in different ways than other subpopulations of species "A". Eventually, the subpopulation will be different enough that it will be considered a different species from the original population.
If you're really curious about this topic, reading about "ring species" will be really informative.