To remove the shortcomings of the two kingdom classification. Whittaker has proposed a new five kingdom classification. It is based on:
1. Complexity of cell structure i.e. prokaryotic or eukaryotic unicellular organisms have been separated.
2. Complexity of body organization i.e. unicellular or multicellular or tissue grade of organization have been arranged in different groups.
3. Phylogenetic relationships have been taken into consideration. Animals have been arranged considering their food habits.
4. Modes of nutrition, i.e. autotrophic, heterotrophic. The five kingdoms recognized – mobera, protista fungi, plantae, and animally are-
a. Monera:- It includes unicellular, prokaryotic organisms e.g. Blue, green algae, other bacteria.
b. Protista:- It includes unicellular, eukaryotic saprophytic or holozic or autotrophic organisms, e.g. protozoa.
c. Fungi:- It includes multicellular, syncytial saprozoic, e.g. mushrooms, mould, slime.
d. Plantae:- It include multicellular, tissue well formed autotrophs, e.g. algae, flowering and non-flowering plants.
e. Animalia:- It includes multicellular tissues well formed, motile, holozoic, e.g. all metazoan animals.
The classification of animal is concerned with only protista and animally kingdoms.