Question

why are the classification systems changing every now and then​

Answer 1

Evolution is the major factor responsible for the change inclassification systems. ... Due to evolution, animal and plant species keep on changing, so necessary changes in the already existedclassification systems are necessary to place every newly discovered plant and animal in their respective ranks.

Answer 2

Evolution is the major factor responsible for the change in classification systems. Since, evolution still continues, so many different species of plants and animals are added in the already existed biodiversity. These newly discovered plant and animal specimens are then identified, classified and named according to the already existing classification systems. Due to evolution, animal and plant species keep on changing, so necessary changes in the already existed classification systems are necessary to place every newly discovered plant and animal in their respective ranks.

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