Can inter-breeding change an animal species?

Absolutely! I've just been watching "Darwin The Struggle with Evolution" I agree 100% with what he says. Seeds from the same plant falling and growing in different environments and producing slightly different plants. Absolutely true hence evolution. He makes an example of the different species of pigeons which came from an original but gradually changed into the different species we have today. Absolutely true. So to me the only way humans could have evolved from apes was from inter-breeding between them and humans which I wouldn't put past human beings and there is absolutely no other way. But will we ever know? That is the big question.