Question

Define a Taxon. Give some examples of taxa at different hierarchical levels.

Answer 1

Hint:The process of classification of living organisms is not a single step process but involves several steps, i.e., a hierarchy of steps in which each step represents a rank or category.

Complete answer:
Taxon (plural: taxa) represents any level of grouping of organisms based on certain easily observable common characteristics like insects represents a group of organisms that share some common features like three pairs of jointed legs, hence insects can be uniquely recognized and classified.

Common names	Biological name	Genus	Family	Order	Class	Phylum OR Division	Kingdom
Man	Homo sapiens	Homo	Hominidae	Primata	Mammalia	Chordata	Animalia
Housefly	Musca domestica	Musca	Muscidae	Diptera	Insecta	Arthropoda	Animalia
Mango	Mangifera indica	Mangifera	Anacardiaceae	Sapindales	Dicotyledonae	Angiospermae	Plantae
Wheat	Triticum aestivum	Triticum	Poaceae	Poales	Monocotyledonae	Angiospermae	Plantae
Brinjal	Solanum melongena	Solanum	Solanaceae	Polymonials	Dicotyledonae	Angiospermae	Plantae

Additional Information: The process of classification of living organisms is not a single step process but it involves several steps i.e., a hierarchy of steps in which each step represents a rank or category. Since the category is a part of the overall taxonomic arrangement, it is called a Taxonomic Category.  
The diverse kinds of organisms are classified into seven obligate categories in which all living organisms are classified in a descending sequence starting from kingdom to species or in ascending sequence starting from species to kingdom. 
The hierarchical arrangement is as follows: - Kingdom - Phylum (for animals) or Division (for plants) - Class - Order - Family - Genus - Species - Kingdom: It is the highest category in the taxonomic hierarchy. It is a group of phyla or divisions, which have certain basic common characteristics.  - Phylum/ Division: It is a category higher than class. The term “Phylum” is used for animals whereas the term “division” is used for plants. Different classes, comprising animals like fishes, amphibians, reptiles, birds, and mammals together constitute the phylum Chordata in kingdom Animalia. - Class: A class is a group of one or more related orders. Class is an assemblage of order with similar characteristics. For example, the order Rodentia, Primata, and Carnivora are all placed together under the class Mammalia as they have milk-producing glands and hair on their skin. - Order: It is a group of families that means related families are kept in the same order. For example, the family Felidae and family Canidae are placed under the order Carnivora. - Family: The next category after the genus is family. It includes various groups of related genera, which share less number of similarities as compared to that of genus and species. For example, the genus Felis of cats and the genus Panthera including lion, tiger, and leopard are placed under the family Felidae. - Genus: It is a group of similar species that, in contrast to species in other genera, has more characters in common. For example, the genus Panthera involves species like leo, tigris, and pardus. - Species: A species is a group of actually or potentially interbreeding populations that is reproductively isolated from other such groups. All the species represent the different organisms that are kept in the same genus due to some similarities in their morphological features.

Note:  
- Taxonomists have also developed some sub-categories like sub-phylum or sub-division etc. in this hierarchy to make the arrangement more transparent and scientifically useful.
- Each category is referred to as a unit of classification. It also represents rank in the taxonomic category.
- A taxon represents any level of grouping of organisms based on certain easily observable common characteristics,
- Specificity decreases when we go from species to kingdom i.e., the higher the category, the lesser will be the number of similar characteristics of the organisms belonging to that category.
You can use the following pneumonic to remember the hierarchy.
Kids – Kingdom Prefer – Phylum Cheese – Class Over – Order Fried – Family Green – Genus Spinach – Species