Two ‘species’ of butterfly (Heliconius himera and H. erato) can mate and produce fertile hybrids, but the adults look completely different from one another. Within its lifetime, it cannot be evolve a new phenotype by natural selection in response to its environment.
Darwin’s theory was also imaginary because evolutions can not stops- like the earth, like the butterfly. It stills remain changing…
Darwin conceded that, "If it could be demonstrated that any complex organ existed, which could not possibly have been formed by numerous, successive, slight modifications, my theory would absolutely break down."
Suppose a member of monkeys developed a functional advantage (it loses tails and migrate into human) its offspring would inherit that advantage and pass it on to their offspring. The inferior (disadvantaged) members of the same monkeys would gradually die out, leaving only the superior (advantaged) members of the monkeys. If this happens why there are stills monkeys in the world? It’s really a matter of laugh.
An irreducibly complex system is one composed of multiple parts, all of which are necessary for the system to function. If even one part is missing, the entire system will fail to work functionally. Every individual part is integral. Any system could not have evolved piece by piece. For an example: the mousetrap is composed of five basic parts. If one part is missing (like the tail of monkeys) the mechanism will not work anymore because each individual part is integral.
The tiniest bacterial cells are less than 10-12 grams in weight. Which is in effect of veritable micro-miniaturized factory containing thousands of exquisitely designed pieces of intricate molecular machinery, made up? Altogether of one hundred thousand million atoms, far more complicated than any machinery built by man and absolutely without parallel in the non-living world.
And we don't need a microscope to observe irreducible complexity. The eye, the ear and the heart are all examples of irreducible complexity, though they were not recognized as such in Darwin's day. At last Darwin confessed to suppose that the eye which adjusts the focus to different distances, which is admitting different amounts of light, could have been formed by natural selection, for that reason he freely confessed to absurd in the highest degree…