Larva of the Desert Locust Schistocerca gregaria, in the last nymphal stage before adulthood and in the gregarious phase. Under conditions of overcrowding, nymphs of this species undergo a 'phase' change both in colouration and behaviour. They enter a gregarious phase (as opposed to the normal solitary phase) and assume the bright colours seen here. They mass together in enormous numbers, becoming highly excited & set off in a purposeful manner devouring all vegetation that they encounter. The adults inherit this excitable behaviour, forming the familiar devastating flying swarms of locusts.