First, I thank you for posting a definition of what I am supposed to not understand. What you posted is exactly what I understood evolution to be postulating. This version varies of course slightly with other versions of how evolution allegedly occurred, but I think this is a pretty good summation. Thank you again.
OK. Evolution (in biology) means that a population changes over time. This change happens during the reproduction process of the individuals this population consists of. So you get offspring that has a mix of its parents genetic material plus some mutations which always occur to some extent. Some of these new configurations can produce individuals that are better suited to their environment than their parents or their siblings, so they have higher chances to procreate and on average they also have more offspring.
Up to hear I agree.
Over time the genetic makeup of this population can change considerably.
I fall off track here. Significant mutations of the kind postulated by evolutionists are not seen. The genetic makeup of an ape does not eventually over any number of years make a man. The specific "this is a man" element is missing from his make up.
So if you had a specimen from the current population and one from the ancestor population and compared them, it can make sense to assign them to two different species.
Species, being a man-made classification.
Of course a population can also split up, and the two (or more) groups get reproductively isolated.
No matter what variation in human population you see, a pigmy is still as much of a man as a North American scientist. You are not going to get the kind of change you are reaching for.
This means that changes that arise in one group are no longer shared with the other group(s).
According to the hypothesis which said that they shared reproductive capability before.
Usually these subpopulations are exposed to different environmental conditions which means that natural selection affects them in different ways.
If they stay isolated long enough,
How long is 'long enough'?
it can happen that they changed so much that they don't recognize each other as potential mates. This can be nicely observed in ring species where the two populations at the end of the 'ring' don't recognize each other (here is a nice illustration of a warbler ring species).
Assuming they were genetically fit to reproduce with the comparison species to begin with.
The specific "this is a man" element is missing from his make up. Huh? What is a "man" element?
The difference between humans and apes (and as well as other mammals) is a difference in degree and not in kind. I'm sure every geneticist you'll ask will confirm this.
Species, being a man-made classification.
Yes, that's what I'm saying all the time. And there are even several species concepts depending on the situation
No matter what variation in human population you see, a pigmy is still as much of a man as a North American scientist. You are not going to get the kind of change you are reaching for.
That's true, we are still pretty similar but you don't know that this can't happen if you keep the pigmies isolated long enough. Of course, since a human life span is pretty long this can take quite some time (my layman estimate would be some hundred thousands of years).
According to the hypothesis which said that they shared reproductive capability before.
Which hypothesis? I think even you will agree that the members of a population should be able to interbreed with each other. I mean these two groups were part of one population in the past.
How long is 'long enough'?
Well, this can be thousands of years or even a few million. It depends a lot on the duration of a reproductive cycle as well as on the environmental stress on that particular population.
Assuming they were genetically fit to reproduce with the comparison species to begin with.
Not sure what you're meaning here.