Excellent comments so far. Good thread!:jointsmile: I understand exactly what you are saying and it does make sense. Even in the bible it says the earth is ours to do what we will with it. Man has dominion over the animals the fish the birds and so on. As far as the question of dams goes i would say the difference is only the size which in turn effects a lot more things. A beaver dame does change the flow of a stream. There are almost no negative effects to this that i know of. When humans build large dams like the hoover dam we are permanently altering the course of massive rivers for our benefit. This is not necessarily a bad thing but then we end up destroying ecosystems and food chains. Ultimately this could bite us in the butt. For example lets say that a certain animal or plant becomes extinct. Because of this whatever animals eat this animal or plant are affected. And if it is the only food they eat then they become extinct and so on. I know that sounded confusing and i apologize.
Anyways lets say we continue polluting our world and making it worse. In 100 years or so what if we have made extinct many living organisms? What if we damage the earth so much that we can no longer live here? And if we don't have interplanetary travel or other space stations or whatever for people to go to then many of us will die. Although of course thats a hypothetical and probably wouldn't happen anyway.
The point is that by harming our enviroment we could ultimately destroying ourselves and that is not good.
p.s. this is one of the better threads in the lounge in a long time.