Different kinds of creatures have different number of chromosomes. Human beings, for example, have 23 pairs. Chinchillas have 32. Fruit flies have two. So to get from the most primitive, one-celled organism to a fully functional human being, you have to successively add 22 pairs of well-formed chromosomes.This is completely impossible. Here's why:
Viability
Unlike minor mutations in genetic code, chromosomal abnormalities almost always result in stillbirth. Mammals, in particular, will almost always spontaneously and naturally abort a fetus with such a severe birth defect. Yet evolutionary speciation depends on creatures with a different number of chromosomes from their parents being born on a fairly regular basis.
Fertility
For speciation to occur, its not enough to have an extra chromosome. You also have to be able to reproduce. Of the few chromosomally abnormal creatures that make it past birth, most either die before puberty or are sterile. This effectively halts the speciation process in its tracks.
Advantage
Of the few types of chromosomal abnormalities that are viable at birth, none are advantageous. Mongoloidism is perhaps the best example of a viable chromosomal abnormality in humans. Victims of Thalidomide are another. No one would ever claim that these are advantageous mutations. Yet, despite the fact that science has never recorded a single instance of a functionally advantageous chromosomal anomaly, evolution depends entirely on the occurrence of such events millions of times.
Mating
Assume a new creature with one more chromosome than its parents survives and is fertile. Assume further, for argument's sake, that this creature's chromosomal abnormality has not resulted in some physical defect that makes it totally unsuitable as a mate. For this extra chromosome to be passed on to the next generation, such a creature would have to find a partner of the opposite sex with the exact same chromosomal abnormality! Otherwise, they wont be able to have children at all -- let alone children with this a wonderful new evolutionary advancement.
The scenario is absurd on the face of it. A proud 12-chromosome momma and papa give birth to some strange 13-chromosome baby boy. Instead of kicking this totally bizarre creature out of their nest, momma and papa nurture their unique progeny until he reaches maturity. At that point, he begins searching the world for the beautiful 13-chromosome girl of his dreams. Somehow, he finds her and they propagate happily ever after.
It's an oversimplified view, perhaps. But it gets at the heart of the problem. Speciation simply can't occur in nature. It never has and never will. So how did we get sold on it in the first place?
