How the slot machine led biologists astray.

An extensive search, in the literature, for experiments in which a new enzyme did evolve, produced only two: the first by Campbell et al. in 1973; the second by Hall & Hartl in 1974. Since the experiments provide the only means of gaining a first hand view of how new enzymes evolve, they were scrutinized, minutely, with the objective of ascertaining whether the mutations involved were random or non-random. We report here that they were non-random. Further, with the benefit of hindsight, we highlight the weakness in the insights and the reasoning which produced the belief that new enzymes evolve purely by chance.