Numerical taxonomy
 |
Numerical taxonomy or Phenetics is a classification system in biological systematics. It aims to create a taxonomy using numeric algorithms like cluster analysis. The concept was first developed by Robert R. Sokal & Peter H.A. Sneath in 1963[1] and later elaborated by the same authors[2].
Although intended as an objective classification methods, in practice the choice and weighing of morphological characteristics is often guided by available methods and research interests. Furthermore, the general consensus has become that the taxonomic classification should reflect evolutionary (phylogenetic) processes. Some connections between phylogenetic trees and the spectral decomposition of the variance-covariance matrix of quantitative traits subject to Brownian motion over time have been established [3], providing a theoretical link between phylogenetic methods and numerical taxonomy. The specific phenetic algorithms proposed in numerical taxonomy, however, often fail to properly reconstruct the phylogenetic history of organsims.
Numeric taxonomy remains useful in cases where biological species concepts can not be applied, e. g. clonal evolution as in apomictic microspecies like blackberries.
References
- ^ Sokal & Sneath: Principles of Numerical Taxonomy, San Francisco: W.H. Freeman, 1963
- ^ Sneath und Sokal: Numerical Taxonomy, San Francisco: W.H. Freeman, 1973
- ^ Cavalli-Sforza, L. (1975). "Analysis of Evolution: Evolutionary Rates, Independence and Treeness". Theoretical Population Biology. 8: 127–165.
{{cite journal}}: Unknown parameter|coauthors=ignored (|author=suggested) (help)