R.H. Whittaker, an American taxonomist proposed five kingdom classification in the year 1969. The kingdoms include Monera, Protista, Fungi, Plantae and Animalia. The criteria adopted for the classification include cell structure, thallus organization, mode of nutrition, reproduction and phylogenetic relationship. A comparative account of the salient features of each kingdom is given in table.
Merits:
- The classification is based on the complexity of cell structure and organization of thallus.
- It is based on the mode of nutrition.
- Separation of fungi from plants.
- It shows the phylogeny of the organisms
Demerits:
- The kingdom monera and protista accommodate both autotrophic and heterotrophic organisms, cell wall lacking and cell wall bearing organisms thus making these two groups more heterogeneous.
- Viruses were not included in the system.
