Egyptian fruit bat their days roosting in trees or caves, often with large groups of other bats, sometimes numbering in the thousands. They emerge from the roost to forage for food in the late evening, and return just before dawn. They hang upside down, with their wings folded closely around their bodies. Egyptian fruit bats, along with other species in the genus "Rousettus", are the only megachiropterid bats to use echolocation, which they accomplish by emitting a series of sharp clicks with their tongues. The clicks are normally slow and constant, but these clicks speed up dramatically when the bats approach an object.
Animal echolocation mammals other than bats known to echolocate include two genera ("Sorex" and "Blarina") of shrews and the tenrecs of Madagascar. These include the wandering shrew ("Sorex vagrans"), the common or Eurasian shrew ("Sorex araneus"), and the short-tailed shrew ("Blarina brevicauda"). The nature of shrew sounds unlike those of bats are low amplitude, broadband, multi-harmonic and frequency modulated. They contain no ‘echolocation clicks’ with reverberations and would seem to be used for simple, close range spatial orientation. In contrast to bats, shrews use echolocation only to investigate their habitat rather than additionally to pinpoint food. There is evidence that blinded laboratory