"In the November 7th or November 14th issue of Science magazine, a number of investigators wanted to test the Darwinian hypothesis that you folks say is never tested, and the way in which they did this was to take the receptor protein for the human growth hormone--it's a receptor to which the human growth hormone fits in precisely--and they did a terrible genetic disservice. They mutated--they cut out an essential amino acid right in the middle of the receptor, called tryptophan. With that gone, just like that mousetrap, it wouldn't have been expected to work. They then allowed a natural selection process to take place to see whether the cells under their own observation could mutate the receptor gene sufficiently to bind the receptor, and after seven generations, lo and behold, there it was. It illustrates beautifully the ability of natural selection to respond to mutations in proteins to coevolve." - Ken Miller in "Resolved: That evolutionists should acknowledge creation" Firing Line, 4 December 1997, p. 25.