[brokenkebaby]

The analogy doesn't work for the nature. It already went through very drastic changes, at least some of them attributed to activities of living organisms, and while it was bad for some species, it was good for others. It's even more so when we're talking about less than cataclysmic changes. It's hard to find any clear logic why disappearance of dodo bird is bad, and e.g. extinction of horses in America is ok.