I can't imagine why you think those are clever questions, when the answers are so obvious.
By definition of the word "speciation", it happens when sub-populations are separated from each other and no longer interbreed.
Each sub-group must survive under different conditions, and so habituates, acclimates, adjusts, modifies, adapts and yes, over longer periods, evolves until they are no longer physically able to interbreed.
In this process, scientists label them as different breeds, subspecies, species, genera, etc.
As for "that ape-to-man transitioning", of course there are biological changes in every generation, some for the better, most for the worse.
In most of nature, natural selection weeds out the worst changes.
Today amongst humans, we rely more on science and medicine to accomplish what we don't want natural selection doing for us.
What were your detailed, logical, believable answers to the questions presented at considertheprobabilities.com?