Experimental studies of the ontogeny of ultrasonic vocalizations in bats.

The ontogeny of FM pulses emitted by bats is a process of maturation that is not easily altered by experimental manipulation during early development. Infants that were hand-raised and infants that were raised by mothers with altered voices (the superior laryngeal nerves were cauterized pre- and postpartum) emitted normal adult calls. Effects of pinching the superior laryngeal nerves of young bats with a cold forcepts on their vocalizations suggest that the development of this nerve and its associated musculature occurs early in the bat's postnatal life.