Artificial System Classification of Plant Kingdom: In this system of classification only few characters of the plants are being considered, e.g., grouping of plants by habit (herbs, shrubs or trees) or importance to man (medicine, food) etc. There are many drawbacks in this system, plants closely resembling each other are often placed in widely separated groups, while those quite different from each other are being placed in the same group. This system is just like alphabetical arrangement of words in a dictionary, where two words arranged one after the other have nothing to do with each other. This system is not commonly in current use.

Artificial System Classification of Plant Kingdom

Some examples of artificial system are the classifications proposed by Theophrastus (370-285 B.C.), Bauhin (1560-1624), Tournefort (1656-1708) and Linnaeus (1707-1778).

• In an artificial system of classification gross, superficial and morphological characteristics are taken into account for classification.
• Vegetative (habit, number ,shape and colour of the leaf) and sexual characters (structure of androecium) give equal importance which is not acceptable as vegetative characters are more easily effected by the environment.
• Some of the important contributions are discussed as follows-

a. Aristotle:
i. He used simple morphological characters to classify plants into herbs, shrubs and trees.
ii. He classified animals into Anaima and Enaima, on the basis of absence and presence of RBCs respectively.
 

b. Theophrastus, the inventor of botany, divided plants into four categories based on their habit:
– Herbs
– Under Shrubs
– Shrubs
– Trees
i. “Enquiry into plants” (also known as Historia Plantarum) and “Causes of plants” are his two writings on plants.
ii. He wrote about almost 500 distinct plant species, naming them by the names that were popular at the time.

c. Carl Linnaeus proposed an artificial system of classificationon the basis of few sexual characters like on the androecium structure (number of stamens), in his book Genera Plantarum. He classified plants into 24 classes. Out of them, 23 were of phanerogams and 24th class was of cryptogams.

Demerits of Artificial System Classification of Plant Kingdom

• It uses only one or a few traits for comparison.
• Closely related organisms get separated.
• The grouping is done on the basis of external traits.
• It does not bring out natural and phylogenetic relationships.

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By Team Learning Mantras