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For other uses, see Systematics (disambiguation).
A comparison of phylogenetic and phenetic concepts


Definition and relation with taxonomy[edit]




The term "systematics" is sometimes used synonymously with "taxonomy", and may be confused[by whom?] with "scientific classification". Webster's 9th New Collegiate Dictionary of 1987 treats "classification", "taxonomy", and "systematics" as synonymous. According to this work the terms originated in 1790, c. 1828, and in 1888 respectively. Some[who?] claim systematics alone deals specifically with relationships through time, and that it can be synonymous with phylogenetics, broadly dealing with the inferred hierarchy[citation needed] of organisms, which means it would be as subset of taxonomy as it is sometimes regarded, but the inverse is claimed by others.[who?]

Europeans tend to use the terms "systematics" and "biosystematics" for the field of the study of biodiversity as a whole, whereas North Americans tend to use "taxonomy" more frequently.[3] However, taxonomy, and in particular alpha taxonomy, is more specifically the identification, description, and naming (i.e. nomenclature) of organisms,[4] while "classification" focuses on placing organisms within hierarchical groups that show their relationships to other organisms. All of these biological disciplines can deal both with extinct and with extant organisms.


Phenetic systematics was an attempt to determine the relationships of organisms through a measure of similarity, considering plesiomorphies (ancestral traits) and apomorphies (derived traits) as equally informative. From the late-20th century onwards, it was superseded by cladistics, which considers plesiomorphies to be uninformative for an attempt to resolve the phylogeny of Earth's various organisms through time. Today's systematists generally make extensive use of molecular biology and of computer programs to study organisms.

Taxonomic characters[edit]

Taxonomic characters provide the evidence from which relationship (the phylogeny) between taxa is inferred. [5] Kinds of taxonomic characters:[6]

See also[edit]



  6. ^ Mayr, Ernst (1991), p. 162.

Further Reading[edit]

External links[edit]