7. What are the reasons that you can think of for the arthropods to constitute the largest group of the animal kingdom?


The phylum, Arthropoda, consists of more than two-thirds of the animal species on earth.
The reasons for the success of arthropods are as follows.
 Jointed legs that allow more mobility on land
 Hard exoskeleton made of chitin that protects the body
 The hard exoskeleton also reduces water loss from the body of arthropods
making them more adapted to terrestrial conditions.