[Modernman]

I want to see one species "re"produce and out pop a different species.

Species are a continuum more than they are dividing lines. A population evolves gradually until it can no longer interbreed with the parent species. There are plenty of fuzzy lines, of course.

Small, gradual changes over time are the mechanism by which a population of one species evolves into another species.

I'm genuinely curious. Have humans ever successfully mated with apes?

I don't think so. I doubt we would be close enough for even a hybrid to be born (unlike, say, lions and tigers, which can mate to create a usually infertile hybrid)

[DameAutour]

Lions and tigers are both felines. It is "cat" and "cat", I'm looking for "cat" and "not cat". I'm assuming such exists. A population evolves gradually until it can no longer interbreed with the parent species.

That is what I am looking for. The population that could interbreed with the parent species and the one immediately following that couldn't.