Answer:
A growth of a population can get to a point that its own species are going to start competing for the same resources.
Step-by-step explanation:
Imagine an island, and in this island, there's a species of organism that eats coconuts, but this species is growing with time, and after some time, this species is big enough that this resource is not enough for all of them, so this population won't increase anymore, some of them won't eat anymore because of the competition for this source of food, and without food, the organism will not survive, and in that way, the population is slowed by its own numbers.