I wish someone like you would have the time to explain to me the time frame, the fossil & other archeological records, and the evidence of the observable progression from, say, Neanderthal Man to King Tut.
Because I don't get it and I don't know where to look.
Here is a wiki article with lots of charts & graphs that could begin to explain. It includes representations like these:
Of course, I "get" that your terms "evidence of observable progression" are usually code words for "I don't believe a word of it, and won't accept anything you say", but on the off-chance that you just randomly picked those words, I'll make an effort -- in all good faith -- to explain it.
Well, here’s one way it works: they find some primate bone fragments, maybe a few teeth, half a jawbone and a crushed femur. Some scientists come up with a conceptual idea of what that primate must have looked like, based on their preexisting bias that the primate must be an intermediate form between other primates and homos.
Then they show you a sequence of such conceptual renderings and call it “objective”.