1. They control populations of many animals, especially some insects that cause damage to crops and spread diseases.
  2. They eat fruits and disperse seeds of many pioneer plants, thus helping them  to reproduce and colonize new sites. Therefore, they play a central role in forest regeneration.
  3. They pollinate flowers of several plants, allowing fecundation and production of fruits and seeds.
  4. They are natural vectos of some diseases, like rabies, and so help to control populations of other animals.
  5. They are very important in the structure of tropical forests and play a central role in some ecological services, because of the many kinds of interactions they have with other organisms.
  6. They have been used as amodel for developing many human technologies, like the sonar, the medical ultrasound, modern economic and radar-invisible airplanes, and drugs for blood diseases.