Bat prevent them from spending too much time in unfamiliar places, and decrease predation. In some species, pregnant individuals may not use torpor. The smallest bat is Kitti's hog-nosed bat ("Craseonycteris thonglongyai"), which is long with a wingspan and weighs . It is also arguably the smallest extant species of mammal, next to the Etruscan shrew. The largest bats are a few species of "Pteropus" megabats and the giant golden-crowned flying fox, ("Acerodon jubatus"), which can weigh with a wingspan of . Larger bats tend to use lower frequencies and smaller bats higher for echolocation; high-frequency echolocation is better at detecting
Ghost-faced bat of food. They are often found feeding over standing water. Because these bats tend to roost in larger colonies they are susceptible to parasites and rabies which have been known to wipe out entire colonies. The ghost-faced bat survives on a diet of small insects. They use echolocation to identify their food at night and are able to catch insects in the darkness with little or no additional light. Very little is known about their reproduction and development. These bats only seem to carry one embryo at a time and are thought to give birth in the spring between March