2. Systematics of Living Organisms- part 01 -Systematics and Classification 1

 


2. Systematics of Living Organisms- part 01 -Systematics and Classification


Systematics :
  • ‘‘Systematics is the study of kinds and diversity of organisms and their comparative and evolutionary relationship’’(G. Simpson, 1961).
Taxonomy :
  • Taxonomy means classification following certain rules or principles. 
  • Word Taxonomy comes from two Greek words, taxis – meaning arrangement and nomous meaning law or rule. 
  • The term taxonomy was first introduced by A. P. de Candolle (Swiss Botanist) [1778-1841].
Classification :
  • It is the arrangement of organisms or groups of organisms in distinct categories in accordance with a particular and well established plan. 
  • This classification is based on similarities and dissimilarities among the organisms.
Artificial :
  • It is the classification that is based on few easily observable and non-evolutionary featurs such as habit, colour, form, etc.; often irrespective of their affinity (relationship) with other organisms. 
  • e.g. Linnaeus system of classification.

Natural : 
  • It is the classification which is based on objectively significant rather than being selected for convenience like artificial system of classification 
  • e.g. Bentham and Hooker's system of classification.

Phylogenetic :
  • It is the classification based on common evolutionary descent. 
  • e.g. Engler and prantles classification.
  • In the system of classification the terms like‘taxa’ and ‘categories’ are often used. 
  • Each category is referred to as a unit of classification. In fact, it represents a rank and is commonly termed as taxon.

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