Brill, Frida (2012) Cladistics (method of classifying species of organisms into groups). University Publications, Delhi, India. ISBN 9788132337263
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Abstract
Cladistics is a method of classifying species of organisms into groups called clades, which consist only of firstly, all the descendants of an ancestral organism and secondly, the ancestor itself. For example, birds, dinosaurs, crocodiles, and all descendants (living or extinct) of their most recent common ancestor form a clade. In the terms of biological systematics, a clade is a single "branch" on the "tree of life", a monophyletic group. [D A Cladistics can be distinguished from other taxonomic systems , such as phenetics , by its focus on shared derived characters (snapomorphies). Systems developed earlier usually employed overall morphological similarity to group species into genera, families and other higher level groups (taxa); cladistic classifications (usually in the form of trees called cladograms) are intended to reflect the relative recency of common ancestry or the sharing of homologous features. Cladistics is also distinguished by an emphasis on parsimony and hypothesis testing (particularly falsificationism), leading to a claim that cladistics is more objective than systems which rely on subjective judgments of relationship based on similarity. Cladistics originated in the work of the German entomologist Willi Hennig, who referred to it as "phylogenetic systematics" (also the name of his 1966 book); the use of the terms "cladistics" and "clade" was popularized by other researchers. The technique and sometimes the name have been successfully applied in other disciplines: for example, to determine the relationships between the surviving manuscripts of the Canterbury Tales. Cladists use cladograms, diagrams which show ancestral relations between species, to represent the monophyletic relationships of species, termed sister - group relationships. This is interpreted as representing phylogeny, or evolutionary relationships. Although traditionally such cladograms were generated largely on the basis of morphological characters, genetic sequencing data and computational phylogenetics are now very commonly used in the generation of cladograms. Cladistics, either generally or in specific applications, has been criticized from its beginnings. A decision as to whether a particular character is a synapomorphy or not may be challenged as involving subjective judgements, raising the issue of whether cladistics as actually practiced is as objective as has been claimed.
| Item Type: | Book |
|---|---|
| Subjects: | Q Science > QK Botany |
| Divisions: | Electronic Books |
| Depositing User: | Esam @ Hisham Muhammad |
| Date Deposited: | 12 Feb 2023 06:49 |
| Last Modified: | 12 Feb 2023 06:49 |
| URI: | http://odlsystem2.utm.my/id/eprint/3996 |
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