Cladistics

related topics
{specie, animal, plant}
{math, number, function}
{theory, work, human}
{rate, high, increase}
{style, bgcolor, rowspan}
{system, computer, user}
{government, party, election}

Adaptation
Genetic drift
Gene flow
Mutation
Natural selection
Speciation

Introduction
Evidence
Evolutionary history of life
History
Level of support
Modern synthesis
Objections / Controversy
Social effect
Theory and fact

Cladistics
Ecological genetics
Evolutionary anthropology
Evolutionary development
Evolutionary psychology
Molecular evolution
Phylogenetics
Population genetics
Systematics

Cladistics (Ancient Greek: κλάδος, klados, "branch") is a method of classifying species of organisms into groups called clades, which consist only of firstly, all the descendants of an ancestral organism and secondly, the ancestor itself. For example, birds, dinosaurs, crocodiles, and all descendants (living or extinct) of their most recent common ancestor form a clade.[1] In the terms of biological systematics, a clade is a single "branch" on the "tree of life", a monophyletic group.

Cladistics can be distinguished from other taxonomic systems, such as phenetics, by its focus on shared derived characters (synapomorphies). Systems developed earlier usually employed overall morphological similarity to group species into genera, families and other higher level groups (taxa); cladistic classifications (usually in the form of trees called cladograms) are intended to reflect the relative recency of common ancestry or the sharing of homologous features. Cladistics is also distinguished by an emphasis on parsimony and hypothesis testing (particularly falsificationism), leading to a claim that cladistics is more objective than systems which rely on subjective judgements of relationship based on similarity.[2]

Cladistics originated in the work of the German entomologist Willi Hennig, who referred to it as "phylogenetic systematics" (also the name of his 1966 book); the use of the terms "cladistics" and "clade" was popularized by other researchers. The technique and sometimes the name have been successfully applied in other disciplines: for example, to determine the relationships between the surviving manuscripts of the Canterbury Tales.[3]

Full article ▸

related documents
Chimpanzee
Velvet worm
Lepidoptera
Bat
Caterpillar
Great ape
Galliformes
Reptile
Pygmy Hippopotamus
Moa
Barn Swallow
Diplodocus
Predation
Sea turtle
Bonobo
Triticale
Extinction
Rabbit
Banksia
Basidiomycota
Blue Whale
Human evolution
Acanthocephala
Echinoderm
Ivory-billed Woodpecker
Trogon
Zebra
Boar
Red-eared slider
Evolutionary developmental biology