A common misunderstanding of evolution is that it means a population of X becomes a population of Y. In actuality, it means a population of X becomes a populati

A common misunderstanding of evolution is that it means a population of X becomes a population of Y. In actuality, it means a population of X becomes a population of X AND Y. If X and Y aren't competing for the same resources (speciation commonly happens to take advantage of a different set of resources), then there is no reason they can't coexist indefinitely.