I'm finding it hard to describe what I mean, but here it goes. According to the evolution theory monkeys, apes among others, and humans have a common ancestor - their hereditary line of ascent leads to a common forefather(s). As evolution predicts, let's say, male nipples is a proof that human species is a product of evolution. Where did that male and female beings got separated - became fully developed into separate and distinct entities? What I'm trying to say is: there would be times when, perhaps, male being also had nipples which somewhat looked more like female mammary glands which would simply mean male hadn't become a full male yet, on the other side, maybe female vestigial organ looked more of a male sex organ. Also, before they fully developed how did they reproduce? Were they able to reproduce before the sex organs fully developed? What about all those enzymes, chemicals - without the proper chemicals sexual reproduction is impossible, at least that's what I can possibly think? It's possible I'm thinking along the wrong lines. I'm not a biology student neither am I very knowledgeable about the evolutionary theory. So, please, try to keep your reply as simple as possible so that I and many others like me can understand what you say and appreciate your effort to the fullest. Thank you.