Back Grau evolutiu Catalan Grado (cladística) Spanish Grade évolutif French Grade (biologie) Dutch Grade NB Grad ewolucyjny Polish Grado (cladística) Portuguese Града Russian Evolutionary grade SIMPLE Града (систематика) Ukrainian

Evolutionary grade

Cladogram (family tree) of a biological group. The green box (central) may represent an evolutionary grade (paraphyletic), a group united by conservative anatomical and physiological traits rather than phylogeny. The flanking red and blue boxes are clades (i.e., complete monophyletic subtrees).

A grade is a taxon united by a level of morphological or physiological complexity. The term was coined by British biologist Julian Huxley, to contrast with clade, a strictly phylogenetic unit.[1]

  1. ^ Huxley J. 1959. Clades and grades. In Cain A.J. (ed) Function and taxonomic importance. Systematics Association, London.

Rich TVX News Network Site

Rich TVX News Network Info

© MMXXIII Rich X Search. We shall prevail. All rights reserved. Rich X Search