The difference between humans and other organisms is that humans, having discerned something of how evolution works, are now able to confront their choices consciously. That is not the same as saying that we can now control evolution. I don't know how much of a difference it is in effect: we may be able to perceive our choices and still be unable to choose and act. By overpopulating the planet as we are now doing, for example, we are making an evolutionary choice just as unplanned as that of our hominid ancestors when they began cracking antelope and other hominids over the head with sticks. Nevertheless, we do differ from the first hominids in our having some notion of the implications of our behavior.