numerical taxonomy

n. The branch of taxonomy that uses mathematical methods to evaluate observable differences and similarities between taxonomic groups.

numer′ical taxon′omy

n. classification of organisms by a comparison of large numbers of observable characteristics that are given equal value instead of being weighted according to possible evolutionary significance. [1960–65]

numerical taxonomy

Numerical taxonomy

The grouping by numerical methods of taxonomic units based on their character states. The application of numerical methods to taxonomy, dating back to the rise of biometrics in the late nineteenth century, has received a great deal of attention with the development of the computer and computer technology. Numerical taxonomy provides methods that are objective, explicit, and repeatable, and is based on the ideas first put forward by M. Adanson in 1963. These ideas, or principles, are that the ideal taxonomy is composed of information-rich taxa based on as many features as possible, that a priori every character is of equal weight, that overall similarity between any two entities is a function of the similarity of the many characters on which the comparison is based, and that taxa are constructed on the basis of diverse character correlations in the groups studied.

In the early stages of development of numerical taxonomy, phylogenetic relationships were not considered. However, numerical methods have made possible exact measurement of evolutionary rates and phylogenetic analysis. Furthermore, rapid developments in the techniques of direct measurement of the homologies of deoxyribonucleic acid (DNA), and ribonucleic acid (RNA) between different organisms now provide an estimation of “hybridization” between the DNAs of different taxa and, therefore, possible evolutionary relationships. Thus, research in numerical taxonomy often includes analyses of the chemical and physical properties of the nucleic acids of the organisms the data from which are correlated with phenetic groupings established by numerical techniques. See Phylogeny, Taxonomic categories

numerical taxonomy

[nü′mer·i·kəl tak′sän·ə·mē] (systematics) The numerical evaluation of the affinity or similarity between taxonomic units and the ordering of these units into taxa on the basis of their affinities.

numerical taxonomy

taxonomy

[tak-son´ah-me] the orderly classification of organisms or lists into appropriate categories (taxa), with application of suitable and correct names. adj., adj taxonom´ic.numerical taxonomy a method of classifying organisms solely on the basis of the number of shared phenotypic characters, each character usually being given equal weight; used primarily in bacteriology.

numerical taxonomy

n. The branch of taxonomy that uses mathematical methods to evaluate observable differences and similarities between taxonomic groups.

numerical taxonomy

the study of the relationships between organisms by means of determining the number of characteristics they have in common. see TAXONOMY, CLASSIFICATION. See also CHARACTER INDEX.

单词	numerical taxonomy
释义	numerical taxonomy numerical taxonomy n. The branch of taxonomy that uses mathematical methods to evaluate observable differences and similarities between taxonomic groups. numer′ical taxon′omy n. classification of organisms by a comparison of large numbers of observable characteristics that are given equal value instead of being weighted according to possible evolutionary significance. [1960–65] numerical taxonomy Numerical taxonomy The grouping by numerical methods of taxonomic units based on their character states. The application of numerical methods to taxonomy, dating back to the rise of biometrics in the late nineteenth century, has received a great deal of attention with the development of the computer and computer technology. Numerical taxonomy provides methods that are objective, explicit, and repeatable, and is based on the ideas first put forward by M. Adanson in 1963. These ideas, or principles, are that the ideal taxonomy is composed of information-rich taxa based on as many features as possible, that a priori every character is of equal weight, that overall similarity between any two entities is a function of the similarity of the many characters on which the comparison is based, and that taxa are constructed on the basis of diverse character correlations in the groups studied. In the early stages of development of numerical taxonomy, phylogenetic relationships were not considered. However, numerical methods have made possible exact measurement of evolutionary rates and phylogenetic analysis. Furthermore, rapid developments in the techniques of direct measurement of the homologies of deoxyribonucleic acid (DNA), and ribonucleic acid (RNA) between different organisms now provide an estimation of “hybridization” between the DNAs of different taxa and, therefore, possible evolutionary relationships. Thus, research in numerical taxonomy often includes analyses of the chemical and physical properties of the nucleic acids of the organisms the data from which are correlated with phenetic groupings established by numerical techniques. See Phylogeny, Taxonomic categories numerical taxonomy [nü′mer·i·kəl tak′sän·ə·mē] (systematics) The numerical evaluation of the affinity or similarity between taxonomic units and the ordering of these units into taxa on the basis of their affinities. numerical taxonomy taxonomy [tak-son´ah-me] the orderly classification of organisms or lists into appropriate categories (taxa), with application of suitable and correct names. adj., adj taxonom´ic.numerical taxonomy a method of classifying organisms solely on the basis of the number of shared phenotypic characters, each character usually being given equal weight; used primarily in bacteriology. numerical taxonomy n. The branch of taxonomy that uses mathematical methods to evaluate observable differences and similarities between taxonomic groups. numerical taxonomy the study of the relationships between organisms by means of determining the number of characteristics they have in common. see TAXONOMY, CLASSIFICATION. See also CHARACTER INDEX. FinancialSeeCluster analysisThesaurusSeetaxonomy
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