Locusts Perched On Green Leaves Stock Photo

Locusts are a group of certain species of short-horned grasshoppers, that have a swarming phase. Normally, these grasshoppers are innocuous, their numbers are low, and they do not pose a major economic threat to agriculture. However, under suitable conditions of drought followed by rapid vegetation growth, serotonin in their brains triggers a dramatic set of changes: they start to breed abundantly, becoming gregarious and nomadic when their populations become dense enough. They form bands of wingless nymphs that later become swarms of winged adults. Both the bands and the swarms move around and rapidly strip fields and cause damage to crops.