The five kingdom classification that we see today was not the initial result of classification of living organisms. Carolus Linnaeus first came up with a two kingdom classification which included only plantae and animalia. This system of classification lasted for a very long time but did not last forever because it did not take into account many major parameters while classifying. There was no differentiation of the eukaryotes from the prokaryotes; neither unicellular from multicellular; nor photosynthetic from the non photosynthetic.
Putting all the organisms in either plant or animal kingdom was insufficient because there were a lot of organisms which could not be classified as either plants or animals. All these confusions led to a new mode of classification which had to take into account cell structure, the presence of cell wall, mode of reproduction and mode of nutrition. As a result R H Whittaker came up with the concept of five kingdom classification. This classification of living organisms included the following kingdoms:
This system of classification took a lot into consideration and is till now the most efficient system because the older system was just based on one single characteristic and based on it two highly varied organisms were grouped together. For example, the fungi and plants were placed in the same group just because of the presence of cell wall. In the same way, unicellular and multicellular organisms were also grouped up together.
Thus, all the organisms were classified again into the five kingdoms, starting with Monera, where all the prokaryotic unicellular organisms were placed. Following that, all the eukaryotic unicellular organisms were placed under the kingdom Protista. The organisms were then classified based on presence and absence of cell wall. The ones’ without the cell wall were the animalia and the ones’ with cell wall were again classified into photosynthetic and nonphotosynthetic which included plantae and fungi respectively. This system of classification of living organisms is better than following the older classification of plants and animals because it did not put up the confusion of putting one species in two different kingdoms.
We have thus discussed the five kingdom classification in brief. For detailed understanding download BYJU’s The Learning App.
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