Excellent questions. The issue is speciesism. Humanity wasn't a problem for most of its existence. But it has now started to consume every ressource, spread on every tiny bit of land, and exterminate every other form of life.

If, as you say, humans are as much a product of the earth/universe as any other part of it, what is the justification for speciesism? What gives us the right to take everything for ourselves, kill and decimate other forms of life?

The rate of the extinction of species that the earth is going through right now is unprecedented in all of earth's history, to say nothing of the torture we inflict on farm animals. And this is not an accident. We are doing it on purpose and we're proud of it; we call it "development", when the right word should be: destruction.