We humans have a lot to answer for. This planet is a pretty special place and we manage to do some pretty amazing damage often by simply being to bloody lazy to take care of it.
Visit this chris jordan's site with photos from a tiny island in the middle of the Pacific ocean site for a truly awful view of just how we can manage to screw with our world out of sheer, mundane, ordinary stupidity.
I understand that to grow food, provide homes and get jobs for people we have to compromise the pristine nature of this planet. But this casual killing has no justification.