So, for example, reptiles supposedly evolved their scales into feathers and changed into birds. History can't be proved by science. The alleged historical process of evolution from amoeba to man was not observed by man and cannot be reproduced experimentally. That two fossils from extinct species are genetically related through a long series of mutations in many generations is an unverifiable assumption in every case. It is often even difficult to demonstrate that two living similar species are genetically related.
Biological structures are too complex.
The genetic structure, the proteins coded by the genes, the bodily structures, and the biochemistry and metabolism of all organisms are exceedingly complex and very delicately balanced systems. The theory that such systems could have been produced and can be improved by random mutations is like saying that an electronic computer could be produced and then improved by shooting bullets into a room stuffed full of computer parts. A very few experimentally observed mutations in the fruit fly, Drosophila, reportedly confer slight advantages under special conditions in the laboratory. However, the observed mutated flies have proved generally inferior to the wild type, and under ordinary conditions populations tend to revert to the wild type. The DDT-resistant populations of houseflies illustrate this fact.