BIODIVERSITY -ANIMAL: CLASSIFICATION

Classification:
          Classification is possible because there are certain common features between related organisms but at the same time, they are also distinct from each other e.g., all snakes share certain common features and look more or less similar viz. absence of limbs, body covered with scales, forked tongue, etc. but at the same time a cobra can be easily differentiated from a viper or a krait.

           The original system of classification was artificial and based on few characters only. Therefore, it was rejected and since then continuous attempts have be made to improve it and make it more scientific and universally acceptable. This led to the development of the present taxonomic system proposed by R.H. whittaker and known by his name as Whittaker’s Five-Kingdom System of Classification (1969).

            Here, living organisms are divided into following five kingdoms:

(1)    Monera (prokaryotes)

(2)    Protista (a diverse kingdom consisting mostly of unicellular organisms both plants and animals)

(3)    Plantae (Plants)

(4)    Fungi and

(5)    Animalia (animals)

             However, when phylogenies were worked out on the basis of genetic data, it was found that prokaryotes we markedly different not only from eukaryotes but also from each other. This led biologists to modify the present system and adopt a Three-Domain System.