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
Bahaman funnel-eared bat close to 50% of their mothers’ weight. Females are fully responsible for giving care to their newborn, due to the fact that they give one offspring per event. The population of the Bahaman funnel-eared bat is decreasing due to their declining habitat environment. All funnel-eared bats have, very large and funnel-shaped ears. These allow them to detect near silent sounds and return echoes through echolocation. Small papillae cover the ears of these bats, which increases auditory sensitivity. They use olfactory and tactile cues in communication as other mammals do. This species is not very well known, because they are only