Gordon,

You do know that we all need air to breath, water to drink and food to eat to be able to continue to live?

Even if human beings were not so worthless (im being nice to our species here) we still would be destroying Earth and every living beings and every non-living things because of the number of us alive. We are taking too much space as it is so combine this to the negative things we do it is a wonder why Earth is still standing and that there are still vegetation standing, animals alive in the wild, breathable air, drinkable water and eatable food!