A flying mammal that, apart from its large wings of membranous skin, resembles the mouse. The Scriptures classify the bat among the unclean flying creatures that were not to be eaten by the Israelites. (Lev. 11:19; Deut. 14:18) The varieties encountered in the Near East may have a wingspread of a few inches to more than twenty inches (50.8 centimeters). Both insect-eating and fruit-eating bats are found in Palestine.
The bat can fly under the darkest conditions, for it is equipped with a sort of built-in “sonar” system that enables it, when in flight, to avoid obstacles even as small as a wire as well as to locate insect prey. Through its nostrils the bat emits high-frequency pulses of sound far above the range of human hearing. Its ears are specially designed so as to permit the bat to detect the reflections of its own sounds, thus determining the proximity of surrounding objects, animate or inanimate. The sound emitted is not confused with the echo, since a tiny ear muscle contracts at the precise moment the bat broadcasts its high-pitched sound. Even when tens of thousands of these creatures mill around for hours in a dark cave, there are no collisions. Each bat apparently recognizes its own signals and does not confuse them with those of his neighbors.
During the daylight hours bats generally roost head downward in dark caves or deserted buildings, then come forth at dusk to hunt for food during the hours of darkness. Where large numbers of them roost in one place there is a repulsive, mousy odor. In some caves bat manure has built up into layers of considerable thickness, providing a valuable source of fertilizer. It is doubtless because of the bat’s habit of roosting in dark places that the prophet Isaiah speaks of throwing gods of gold and silver to the bats. A place of darkness and uncleanness is all such idols deserve, instead of the places of honor and prominence accorded them by their deceived worshipers.—Isa. 2:20.