When male lions take over a pride, they kill cubs not belonging to them.
Chimpanzees go out in gangs to try and pick off and kill stray members from other groups.
Dolphin males will sometimes seek out and gangrape females.
Similarly, animals don't have any sense of ecological conservation. If their numbers are not checked by disease or other predators, they will consume all available foodstuffs.
We're actually not that bad, considering the raw power at our disposal. In the latter half of the last century we've started to realize how much harm we can cause in the long run, and there's much greater respect for human rights in many parts of the world. We save the lives of millions who would otherwise have died if left to nature, our quality of life is far superior, we're just generally awesome.
If you don't approve, there's plenty of unclaimed wilderness left in the world, you can go live there in peace and enjoy the loving embrace of nature while living off the land.