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Insects are the most numerous and successful creatures on earth. They belong to a group of invertebrates known as arthropods, which are characterized by their jointed limbs, segmented bodies, and tough outer skeletons.

Unwelcome Pests

Arthropods are seen as troublesome pests by most urban-dwelling humans. Certainly some are destructive. It is estimated that about 20% of crops grown for human consumption are eaten by herbivores insects. Insects also carry diseases that affect animals and human beings-approximately one in 6 people alive today is currently affected by an insect-borne disease.

Insect pests may be classified as:

• Disease causing insects
• Agricultural pests