you do realize that all the theory on how a species 'evolve' to another species are basically conjectures with no real evidence apart from "well logically speaking... it should crossover to the next level of evolution". for one thing, you can never run experiments that can be repeated elsewhere to prove the point where such evolution take place, and turn the hypothesis into a theory, which means to say, technically, evolution is not a theory. why not? because the said evolution process takes millions of years, if it ever does occur, thus a real and proper scientific experiment can never be conducted.

Darwin's was all about natural selection. since the fittest survive, shouldn't there be thousands of mishaps along the way which didn't survive at every generation of the species? why isn't there samples of proto-human that sprouted all possible mutation along the way to choosing the best fit? i would imagine that it would make sense to have thousands of contemporary proto-humans along the way to leave some skeletal evidence, yet along the way, we're seeing rather consistent development.

people have got to start discerning between mutation, adaptation and the concept of evolution.

mutation simply don't last. freak mutation to DNA results in weaker individual, not stronger for better survivability.

changes to adapt to environment such as darker skin, or fairer skin, heavier bones etc, are mere adaptation. it doesn't change the species from one to another.

evolution, even for a single system such as optical system requires changes that has a goal. if such thing exist, the complete system 'evolves' to fit a certain goal, which is a system that enable a creature to use sight. now how does separate parts form towards enabling sight in millions of years if there was not a goal. blindly forming parts of optical system and then in a couple of million years you've got a proper function eye is like waiting for the castle to build itself from all the sand on the beach.