Numerical taxonomy is a
classification system in biological
systematics which deals with the grouping by
numerical methods of
taxonomic units based on their character states. It aims to create a
taxonomy using numeric algorithms like
cluster analysis
Cluster analysis or clustering is the task of grouping a set of objects in such a way that objects in the same group (called a cluster) are more similar (in some sense) to each other than to those in other groups (clusters). It is a main task of ...
rather than using subjective evaluation of their properties. The concept was first developed by
Robert R. Sokal and
Peter H. A. Sneath
Peter Henry Andrews Sneath FRS, MD (17 November 1923 – September 9, 2011) was a microbiologist who co-founded the field of numerical taxonomy, together with Robert R. Sokal. Sneath and Sokal wrote ''Principles of Numerical Taxonomy'', revise ...
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 biology, phenetics ( el, phainein – to appear) , also known as taximetrics, is an attempt to classify organisms based on overall similarity, usually in morphology or other observable traits, regardless of their phylogeny or evolutionary r ...
in which classifications are formed based on the patterns of overall similarities and
cladistics
Cladistics (; ) is an approach to biological classification in which organisms are categorized in groups (" clades") based on hypotheses of most recent common ancestry. The evidence for hypothesized relationships is typically shared derived ch ...
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 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
cladograms using numerical methods rather than subjective synthesis of data.
See also
*
Computational phylogenetics
*
Taxonomy (biology)
In biology, taxonomy () is the scientific study of naming, defining ( circumscribing) and classifying groups of biological organisms based on shared characteristics. Organisms are grouped into taxa (singular: taxon) and these groups are giv ...
References
Taxonomy (biology)
es:Taxonomía numérica
ru:Фенетика