Abstract

Despite the enormous importance and widespread use of the term, it is unclear exactly what a phylogeny represents. It is important to define phylogeny precisely since other central terms like “clade” and “monophyletic” are often defined relative to phylogenetic trees and on some views in taxonomy, taxa must be clades. Edwards presents the common picture in contemporary systematics as depending on the existence of a “species tree” in which phylogeny “records the branching pattern of evolving lineages through time”. But what, precisely, does this mean?