Dave Slayer said:
If humans are apes, why aren't we in the zoo? I mean, we are both animals, right?
Yes, we are both animals.
So why are animals in zoos then? Because they provide entertainment and education to humans.
There is a fundamental difference in all species' attitude towards the other species. We are all apart of one 'organism' if you will; life, and to an extent we will protect that life (This explains why we don't want to kill kittens), we afford certain rights to the other species.
That said, there are several differences between us and the rest of life. We are intelligent, we can use linguistics,
and we have more than just a need for survival. All other animals have the simple and only goal to
survive, but we want more, we desire entertainment and societal input.
In a sense we are satisfying all the animal's needs by having them in a zoo, they don't want to be in their apartment writing books; we do (well, some of us ;))
We're not in zoos because our desire for more than survival warrants additional rights.