In the subtext of many discussions about nature, there is a view of it as a reflection of perfection coming from a kind of evolutionary-based intelligent design. Therefore, we as humans should leave nature alone, because -- for instance -- the weak should be culled to maintain some sort of evolutionary prescribed balance. In this view, the evolutionary process is able to find a perfect balance for each species living in harmony with its environs.
This seems to be a political view, and one that is reactionary at heart. For humans since their beginning have altered nature, and generally in a way that has improved human life immeasurably. Nature unaltered renders a life that is short and brutish, to paraphrase.