Taxonomic hierarchy

M,Sc, II Sem III
Taxonomic Hierarchy

1. M.Sc.II Sem - III Paper X- Taxonomy of Angiosperms Unit III Dr. Swati Pundkar Assistant Professor Department of Botany Shri Shivaji Science College, Amravati .

2. Taxonomic hierarchy   Taxonomic hierarchy  is the process of arranging various organisms into successive levels of the biological  classification  either in a decreasing or an increasing order from kingdom to species and vice versa.” Each of this level of the  hierarchy  is called the  taxonomic  category or rank .

3. Kingdom  is the highest level or rank   of the classification. Example: Plantae Division   is the next level of classification   that consists of number of classes. Example: Magnoliophyta . Class   consists of group of orders which   share few similarities.   Order   includes group of families   which show less similarities among them.  

4. Family   comprises a number of genera   which share some similarities among them. Example: Asteraceae.   Genus   consist of multiple species   which have similar characters but differ from the species of another genus. Example:  Helianthus ,  Tridax . Species   is the lowest of classification   and shows the high level of similarities among the organisms. For example,  Helianthus annuus  and Helianthus  tuberosus . These two species differ in their   morphology. Both of them are herbs but  Helianthus tuberosus   is a perennial herb.

5. Advantages of Taxonomic hierarchy Grouping of living organisms into different categories on the basis of degrees of diversity exhibited by them is possible. Such classification helps one to refer a particular group of plants into appropriate classes . There are two main categories Major Categories- Subdivision, Class, Order are together called Major categories 2) Minor Categories- Genus, Species, Variety are called Minor categories

6. Major categories Division Sub-division (ending with – eae ) Class (- opsida ) Sub-class ( ideae ) Order (-ales/-ae) Sub-order (- nieae ) Family (- aceae )(except 9 families) Subfamily Minor categories Genus Sub-genus ( Section,Sub - section,Series,Sub -series) Species

7. Infraspecific Categories- Any category below the rank of spices is Infraspecific category. Most commonly used categories of this group are sub-species, Variety and Forma.