Is man a useful creature?

What do you think? Is man a useful creature? If you look at the way nature works, you will find that everything in nature is somehow connected to everything else. Every organism is useful to another organism in some way. He's taking up more and more space. Taking space from other living things and plants. He judges everything by whether he can use the thing, the object, for himself. He wants more and more. Not because he needs it to survive, but just because he wants it. It's an incredibly greedy and reckless creature. He's even capable of killing members of his own species just to get something.

It's quite tragic that a creature that has fit itself to be the most intelligent organism in the world A creature that has made itself the ruler of the planet. That the main and only criterion and the only variable that defines success is greed.