出典:Wiktionary
出典:Wikipedia
出典:『Wikipedia』 (2011/04/02 07:59 UTC 版)
A polytomy /pəˈlɪtəmi/, meaning many temporal based branches, is a section of a phylogeny in which the evolutionary relationships can not be fully resolved to dichotomies. In a phylogenetic tree, a polytomy is represented as a node which has more than two immediate descending branches. They present an analytical problem, but can usually be better studied by utilizing more flexible phylogenetic network software such as SplitsTree, which can represent some polytomies as median networks.