The Origin and Early Development of the Method of Minimum Evolution for the Reconstruction of Phylogenetic Trees

Abstract

The method of minimum evolution was introduced by Edwards and Cavalli-Sforza (1963, Heredity 18:553, Ann. Hum. Genet. 27:104-105) for the reconstruction of phylogenetic trees. Its relationship to the subsequently developed parsimony methods and the logical basis of the methods are discussed, with special reference to probability models. The minimum evolution method did not derive from Hennig's phylogenetic systematics but rather as an approximation to the maximum-likelihood solution for a model of random evolution. (Phylogenetic trees; minimum evolution; Darwin principle; Ockham's razor; parsimony.) In The Origin of Species, Darwin (1859) replaced the hypothesis of the individual creation of each species with the hypothe- sis of a single origin of life followed by the evolution of new species. He did not ap- peal to Ockham's razor in support of the change and would probably have been surprised to have been told that his achievement was an example—perhaps the example par excellence—of the application of Ockham's razor. His argument, rather, was one of analogy with the way lineages in genealogies could be traced back to common ancestors. Ockham's razor, sometimes now called the principle of parsimony, is traditionally associated with William of Ockham (ca.