The bat "Uroderma bilobatum" is a member of the family Phyllostomidae, which contains 49 genera and a greater variety in feeding habits than any other bat family. Carnivores, frugivores, and bats that specialize on blood or nectar and pollen are all represented in this family. Commonly known as the American leaf-nosed bats, phyllostomids are characterized by a special structure consisting of a leaf-shaped projection extending up from a “horseshoe-shaped” base attached to their upper lip. These bats send their echolocation calls out their nostrils, and so the noseleaf may help direct the sounds that they emit. Because they emit calls at such low frequencies, standard bat detectors have trouble picking up their calls. Thus they are sometimes called “whispering bats”.