Contrary to what many people believe, bats are not vicious and are not likely to attack humans and transmit disease. Although bats can spread rabies, fewer than one half of one per cent of them are known to have the disease. Many species of bats are extremely important to the stability of the environment and some are economically important. Insect-eating bats destroy large numbers of insects, including mosquitoes and some agricultural pests. Nectar-eating bats and fruit-eating bats transfer the pollen and disperse the seeds of numerous plants, including banana plants, peach trees, and date palms. The droppings of certain cave-dwelling bats sometimes accumulate in thick layers on the floors of caves. This material, called guano, is a valuable plant fertilizer.
Many superstitions have been associated with bats. Because they fly only at night and because they often live in tombs and abandoned churches, they have been regarded as omens of evil. The legendary vampire is a supernatural creature that changes from human form into a bat and sucks human blood.
Many people believe that bats will tangle themselves in human hair, but this belief is false.