What is the difference between grasshoppers and locusts?
From a systematic point of view, there is no difference between grasshoppers and locusts. They both belong to the order Orthoptera, suborder Caelifera, infra-order Acridodea and superfamilies Pyrgomogphoidea and Acridoidea. The two terms are mainly used to describe the remarkable differences in behaviour. Locusts just behave like grasshoppers, when they are at low population densities. They do not aggregate and form swarms. However, at higher densities, locust species become gregarious and can form large swarms. They change their behaviour completely due to changes in their hormonal system. They also change certain morphological characteristics and their colour. The capacity to build up large swarms is what makes locusts such dangerous pests. There is a whole range of species with different tendencies to become gregarious. Desert locusts become gregarious at fairly low population densities. At the other end of the scale, Senegalese grasshoppers need much higher densities.
