a taxonomic group of organisms classified together on the basis of homologous features traced to a common ancestor.
Origin of clade
First recorded in 1957, clade is from the Greek word kládos branch
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
biology a group of organisms considered as having evolved from a common ancestor
Word Origin for clade
C20: from Greek klados branch, shoot
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
"group of organisms evolved from a common ancestor," 1957, from Greek klados "young branch, offshoot of a plant, shoot broken off," from PIE *kele-, possibly from root *kel- "to strike, cut" (see holt).
Online Etymology Dictionary, © 2010 Douglas Harper
A grouping of organisms made on the basis of their presumed evolutionary history, rather than purely on shared features. Clades consist of a common ancestor and all its descendants. The class Aves (birds) is a clade, but the class Reptilia (reptiles) is not, since it does not include birds, which are descended from the dinosaurs, a kind of reptile. Many modern taxonomists prefer to use clades in classification, and not all clades correspond to traditional groups like classes, orders, and phyla. Compare grade.
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