Answer:
Natural selection is the nonrandom process by which biological traits become either more or less common in a population as a function of differemtial reproduction of their bearers. One of the main processes by which natural selection takes place is the competition over resources. The larger the population in a certain area, the more competition takes place. In the long run, it doesn't matter wheather or not the area is overpopulated; within any and every population, competition over resources takes places, so, in turn, natural selection does, too.