Perfect phylogeny is a term used in computational phylogenetics to denote a phylogenetic tree in which all internal nodes may be labeled as such that all characters evolve down the tree without homoplasy. That is, characteristics do not hold to evolutionary convergence, and do not have analogous structures. Statistically, this can be represented as an ancestor having state "0" in all characteristics where 0 represents a lack of that characteristic. Each of these characteristics changes from 0 to 1 exactly once and never reverts to state 0. It is rare that actual data adheres to the concept of perfect phylogeny.
Famous quotes containing the word perfect:
“If we are on the outside, we assume a conspiracy is the perfect working of a scheme. Silent nameless men with unadorned hearts. A conspiracy is everything that ordinary life is not. Its the inside game, cold, sure, undistracted, forever closed off to us. We are the flawed ones, the innocents, trying to make some rough sense of the daily jostle. Conspirators have a logic and a daring beyond our reach. All conspiracies are the same taut story of men who find coherence in some criminal act.”
—Don Delillo (b. 1926)