A clade (frae Auncient Greek κλάδος, klados, "branch") or monophylum (see monophyletic) is a group consistin o an auncestor an aw its descendants, a single "branch" on the "tree o life".[1] The auncestor mey be an individual, a population or even a species (extinct or extant). Mony familiar groups, rodents an insects for example, are clades; ithers, lik lizards an monkeys, are nae (lizards excludes snakes, monkeys excludes apes an humans).

Cladogram (faimily tree) o a biological group. The reid an blue boxes at richt an left represent clades (i.e., complete branches). The green box in the middle is nae a clade, but rather represents an evolutionary grade, an incomplete group, acause the blue clade at left is descendit frae it, but is excludit.

Increasinly, taxonomists try tae name preferably or anly taxa that are clades.


  1. Dupuis, Claude (1984). "Willi Hennig's impact on taxonomic thought". Annual Review of Ecology and Systematics. 15: 1–24. doi:10.1146/annurev.es.15.110184.000245.