Numerical taxonomy is a classification system in biological

systematics Systematics is the study of the diversification of living forms, both past and present, and the relationships among living things through time. Relationships are visualized as evolutionary trees (synonyms: phylogenetic trees, phylogenies). Phy ...

which deals with the grouping by numerical methods of taxonomic units based on their character states. It aims to create a

taxonomy image:Hierarchical clustering diagram.png, 280px, Generalized scheme of taxonomy Taxonomy is a practice and science concerned with classification or categorization. Typically, there are two parts to it: the development of an underlying scheme o ...

using numeric algorithms like

cluster analysis Cluster analysis or clustering is the data analyzing technique in which task of grouping a set of objects in such a way that objects in the same group (called a cluster) are more Similarity measure, similar (in some specific sense defined by the ...

rather than using subjective evaluation of their properties. The concept was first developed by Robert R. Sokal and Peter H. A. Sneath in 1963 and later elaborated by the same authors.Sneath and Sokal: ''Numerical Taxonomy'', San Francisco: W.H. Freeman, 1974 by Tejanshu Ravesh They divided the field into phenetics in which classifications are formed based on the patterns of overall similarities and

cladistics Cladistics ( ; from Ancient Greek 'branch') is an approach to Taxonomy (biology), biological classification in which organisms are categorized in groups ("clades") based on hypotheses of most recent common ancestry. The evidence for hypothesiz ...

in which classifications are based on the branching patterns of the estimated evolutionary history of the taxa.{{cn span, In recent years many authors treat numerical taxonomy and phenetics as synonyms despite the distinctions made by those authors., date=May 2017 Although intended as an objective method, in practice the choice and implicit or explicit

weighting The process of frequency weighting involves emphasizing the contribution of particular aspects of a phenomenon (or of a set of data) over others to an outcome or result; thereby highlighting those aspects in comparison to others in the analy ...

of characteristics is influenced by available data and research interests of the investigator. What was made objective was the introduction of explicit steps to be used to create dendrograms and

cladogram A cladogram (from Greek language, Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an Phylogenetic tree, evolutionary tree because it does not s ...

s using numerical methods rather than subjective synthesis of data.

References

Taxonomy (biology) es:Taxonomía numérica ru:Фенетика

See also

References