Binomial Nomenclature | Definition, Classification & System

All biologists follow internationally agreed and accepted codes of rules or principles while assigning scientific name to known or newly discovered organisms. Binomial nomenclature for scientific naming of organisms was developed by Carolus Linnaeus. This system provides distinct and proper scientific names to variety of organisms. Each name has two parts, i.e., the first part comprises of its generic name, while the second part is the specifiC epithet. This naming system which uses two word format is universally accepted and used, as it is more convenient to understand and follow.

Rules of Binomial Nomenclature: Some universal rules of Nomenclature framed under codes of ICZN, ICBN, etc. are as follows

1. Biological names are generally taken from Latin language irrespective of their origin. New names are derived either from Latin language or Latinised.
2. Each organism is given only one name consisting of two words. The first word in a biological name represents its genus while the second component denotes the specific.epithet.
3. The scientific name is printed in italics or underlined separately when handwritten to indicate their Latin origin.
4. The first word denoting genus starts witha capital letter, while the specific epithet starts with a small letter.
5. The name of the author or discoverer is writen after specific epithet in abbreviated form. For example, Mangifera indica Linn., it indicates that this species was first described by Linnaeus.
6. All the three words (generic name, species epithet and author citation) collectively form binomial epithet.
7. Principle of priority : It is the most important of all the rules of ICBN. If first name given to the organism is valid (in terms of rules), that will be considered at the first prererence. Any other valid name given after that will be considered as synonym. No names are recognised prior to those used by Linnaeus in 1758 in the 10th edition of Systema Naturae for animals and 1753 for plants in Species Plantarum.

Method of writing biological or specific name can be memorised as:

Table shows common and scientific names of different common plants and animals.