Home | | Zoology 11th std | Nomenclature and its Rules

Chapter: 11th Zoology : Chapter 1 : The Living World

Nomenclature and its Rules

The process of assigning scientific names to animals or taxonomic group is called nomenclature.




Giza, Inimene, Emberi, Manna,  Doanna, Umano …….


In all probability these words must be new to you…but they all mean “Human” in different foreign languages! There are presently more than 6000 languages in the world and an animal can be named in more than 6000 ways! Unfortunately it is impossible for anyone to have a good functioning knowledge of most languages and hence there arises a need for a universally accepted scientific naming system for all organisms. The process of assigning scientific names to animals or taxonomic group is called nomenclature. For example, worldwide, the scientific name Homo sapiens denotes human. Classification and grouping were done to facilitate a deeper understanding of the unique characteristics of each organism and its interrelationship among closely related species. It plays a vital role in the arrangement of known species based on their similarities and dissimilarities. Numerous characters such as morphology, genetic information, habitat, feeding pattern, adaptations, evolution, etc., are examined before an organism is named.


One of the primary responsibilities of systematic biology is the development of biological nomenclature and classification. Nomenclature is not an end to systematics and taxonomy but it is necessary in organizing information about biodiversity. Nomenclature, functions to provide names for all taxa at all levels in the hierarchy of life. Naming of the organisms is done based on the guidelines of the International Code of Zoological Nomenclature (ICZN). The scientific name ensures that each organism has only one name.


Binomial Nomenclature (L. Bi-two; Nomen-Name)


Biologists follow universally accepted principles to provide scientific names to known organisms. Each name has two components, a generic name and a specific epithet. This system of naming the organism is called Binomial Nomenclature which was popularised by Carolus Linnaeus and practised by biologists all over the world.


Example, the National Bird (Indian Peafowl) – Pavo cristatus, the National Animal tiger as Panthera tigris, and the Tamil Nadu State bird is the common Emerald doveChalcophaps indica.


Trinominal Nomenclature (Tri – three)


This naming system was proposed by Huxley and Stricklandt, Trinomen means, three names: generic name, species name and sub-species name. When members of any species which have large variations then trinomial system is used. On the basis of dissimilarities, this species gets classified into subspecies. It is the extension of binominal nomenclature system which has an addition of subspecies. All the three names are set in italics and only the generic name is capitalized, if handwritten then it should be underlined separately E.g.Corvus splendens splendens (Indian house crow) Tautonymy: The practice of naming the animals in which the generic name and species name are the same, is called Tautonymy. e.g. Naja naja (The Indian Cobra).


Rules of Nomenclature


                  The scientific name should be italicized in printed form and if handwritten, it should be underlined separately.


                  The generic name’s (Genus) first alphabet should be in uppercase.


                  The specific name (species) should be in lowercase.


                  The scientific names of any two organisms are not similar.


                  The name or abbreviated name of the scientist who first publishes the scientific name may be written after the species name along with the year of publication. For example Lion-Felis leo Linn., 1758 or Felis leo L., 1758.


                  If the species name is framed after any person’s name the name of the species shall end with i, ii or ae.


For example, a new species of a ground-dwelling lizard (Cyrtodactylus) has been discovered and named after Scientist Varad Giri, Cyrtodactylus varadgirii.


Study Material, Lecturing Notes, Assignment, Reference, Wiki description explanation, brief detail
11th Zoology : Chapter 1 : The Living World : Nomenclature and its Rules |

Privacy Policy, Terms and Conditions, DMCA Policy and Compliant

Copyright © 2018-2024 BrainKart.com; All Rights Reserved. Developed by Therithal info, Chennai.