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
Echolocation jamming chemicals from their host plants as caterpillars and keep them in their tissues through adulthood. Roeder agreed with Dunning’s findings. James Fullard and colleagues published findings in 1979, and 1994 arguing in favor of the jamming hypothesis based on the acoustic characteristics of moth clicks, however this hypothesis was still widely debated in the literature during that time. In the 1990s experiments were conducted broadcasting clicks to bats performing echolocation tasks on a platform and with neurophysiological methods to demonstrate a plausible mechanism for jamming. The researchers concluded that most tiger moths do not produce enough sound to jam bat