"The Machinery of Evolution: Out of Gear?"

"One of the most fundamental ideas in modern evolutionary biology is that the physical structures of living organisms can transform from one into another through a series of small modifications, without departing from the realm of potential useful forms. ... Although Darwin admitted he could not imagine the intermediate, transitional forms leading to many different organs, he assumed that they might later be revealed by a deeper understanding of the organs' structure and function, and he proceeded to based his theory on their presumed existence. ... The geneticist Richard Goldschmidt once gave a list of seventeen organs and systems of organs for which he could not even conceive of the required transitional forms. ... We would like to suggest here that for many organs, the reason why required chains of useful intermediate forms are unimaginable is simply that they do not exist. Let us try to visual this in mathematical terms."

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