Scientists say they have identified a chemical released by locusts that causes the insects to join together in huge swarms.On their own, locusts are mostly harmless. But in large swarms, they can be extremely destructive.The new finding could lead to new methods to prevent locusts from joining groups to destroy huge areas of crops.A recent study published in Nature identifies a pheromone believed to be responsible for the insect's swarming behavior.A pheromone is a chemical substance produced by an animal that influences the behavior of another animal of the same kind.The pheromone, known as 4VA, was found in the world's most widespread kind of locust, the migratory locust.The chemical is released from the insect's back legs and is sensed by the antennae of other locusts.The pheromone powerfully drew locusts of both sexes and all ages, the research found.
