In the modern model of evolution theory the evolution of a protein or of an organ behaves like the accidental changes in a drunk man's walk. Mutations in the hereditary DNA occur due to accidental processes. The natural selection of those mutations also is the result of accidental processes. The rapidity with which these processes occur therefore is indeterminate for each mutation.
The evolution biologist Stephen Jay Gould too advocated the model of evolution as a drunk man's walk in his book "Full House: The Spread of Excellence from Plato to Darwin" (1996).
Nevertheless paleontologists and evolution biologists discern trends in the evolution of species that are contrary to the drunk man's walk hypothesis.
This article presents revolutionary arguments that both the occurrence of mutations and their natural selection happen more quickly than is possible in the standard model.