Quote Originally Posted by Mark75 View Post
Not necessarily. We already know about convergent evolution. http://en.wikipedia.org/wiki/Convergent_evolution
convergent evolution is about similar traits happening because of similar environments

why are alien planets going to be like earth? I would expect the universe, as vast as it is, to be diverse. and if we are finding that alien life looks a lot like ours, I think it is something to question that this then means, there are worlds like ours

to even think there is another planet out there with oceans of water, oxygen, and land masses with volcanic activity, is - nothing short of amazing.