The evolution story goes something like this: life arose from goo and evolved to you by the way of the zoo.
The evolution story goes like this: in any species there is a genetic variety. Some of those genes will be more successful than others and be more common in the next generation. Some new genes will be created via random mutation. Over time, the form of the organism becomes better adapted to its environment on average as the better adapted genes survive and propagate. In aggregate this can lead to large changes in the form of the organism.
Example: dog breeding. Instead of the environment favouring genes, the humans choose which traits to keep. This has formed the huge variety of dog appearances we see today from a common wild ancestor. Or watch how new strains of bacteria evolve that are resistant to certain drugs or can infect new animals.
Please try to seperate the mechanism of evolution above, from the specific story you likely dispute of man having evolved from single-celled organisms. It'd be useful for you to understand that evolution as a process can and does happen even if you dispute the second part.
Is there any empirical, observational documentation of an organism population evolving camouflage abilities on the fly like an Indonesian Mimic Octopus or Anole Lizard?
Or an organism evolve special clawed feet to walk vertically and upside down on all walls like an ant? Is their documentation of any creature population evolving feathers or a blow hole or gills? How about a fruitfly evolving glands to produce silk or a spineret or bioluminence abilities or anything of that sort?
What happens is they evolve something entirely different and it turns out to be useful for camoflauge or whatever specialist thing you're thinking of. It's not "trying" to evolve that thing.
How about an organism evolving antennas, a blow hole, gills, a shell, eyes, baleen plates, fluke, arms, legs, trunk, claws, ink dispersal abilities etc. ? Just any radical novel feature or ability would suffice.
Bacteria evolve the ability to metabolise citrate that they didn't have before. No human intervention or selection here btw.
You see, it takes radical changes to get a cell from goo to all the diversity of life we see today. But I have yet to see any documentation of at least one example of any organisms observed while occuring evolve such novel abilities or features. It seems that it is an assumption it happened but without the empirical evidence to back it up.
The empirical evidence is that we have a ton of intermediate forms via fossils and plausible mechanisms for these things to develop from existing cellular machinery or chemicals being used for something else.
And if you didn't know, empirical, observational evidence is part of the scientific method. Thus if there is no empirical, observational evidence then it is not scientific:
" The scientific method is a body of techniques for investigating phenomena, acquiring new knowledge, or correcting and integrating previous knowledge. *To be termed scientific, a method of inquiry must be based on empirical* and measurable evidence subject to specific principles of reasoning."
Rules for the study of natural philosophy", Newton 1999, pp. 794–6, from Book 3, The System of the World
Moreover can the story really be scientifically tested and repeated?
Well, yes. We have no contradictory evidence, such as a feature that couldn't plausibly have evolved on its own, or a species in the wrong stratum. You're free to go out and test the same samples that Darwin used, or find your own that contradict it.
Science is about choosing the best theory that can be supported by the evidence. So far, there's no alternative more plausible than evolution. Feel free to create one and science will accept it if it's better supported.
So is the evolution story really scientific?
Of course it is. Especially compared to the religiously-motivated alternatives.