* Taxis = orderly arrangement, nomos = law. Taxonomy is the study of principles and procedures of classification.This word was proposed by A.P. de. Candolle in his book "Theories elementaire de la botanique'' (Theory of elementary botany)
* Taxonomy includes study of following 4 points
(1) Identification: Identification of living organisms
(2) Nomenclature : Nomenclature of living organisms
(3) Classification: Classification of living organisms in groups
(4) Affinities: Study of inter relationship between living organisms.
Systematics (Branch related with taxonomy)
(A) The term "Systematics" was proposed by Linnaeus.
(B) It includes description of external morphological characters of plants or living organisms. Eg. Morphological characters of Root, Stern, Leaves, Flowers
(C) This description is used to know inter relationship among plants or living organisms.
New systematic or Neo systematic or Biosystematics:
(A) Neo - systematic: A new branch-Name given by Julian Huxley (1940).
(B) It includes description of all the characters (internal) including morphological characters (external) of plants or living organism.
- Eg. Anatomical characters
- Cytological characters
(C) It is used to know the interrelationship among living organism.
- New systematics is mainly based on evolutionary as well as genetic relationship (experimental taxonomy) as compared to morphological characters.
- Maximum diversity is found in tropical rainforests.
- Second maximum diversity is found in coral reefs.
- Practical Significance of taxonomy is identification of unknown organism.