Can't you see that the space aliens described by humans who "contacted" them are not realistic?

What does being a Christian have to do with anything? I don't believe that aliens have been to earth but that belief is based on practical, scientific reasons. It's not based on arbitrary religious interpretations. However if there are aliens out there having different DNA doesn't preclude them being bipedal beings with two arms, two legs and binocular vision. Evolution is all about survival of a species and it could be that those traits are just as advantageous on another planet as they are on earth. They could still have, and would most likely have, DNA that is completely different from our own.