Vocal control of acoustic information for sonar discriminations by the echolocating bat, Eptesicus fuscus

This study aimed to determine whether bats using frequency modulated (FM) e cholocation signals adapt the features of their vocalizations to the percep tual demands of a particular sonar task. Quantitative measures were obtaine d from the vocal signals produced by echolocating bats (Eptesicus fuscus) t hat were trained to perform in two distinct perceptual tasks, echo delay an d Doppler-shift discriminations. In both perceptual tasks, the bats learned to discriminate electronically manipulated playback signals of their own e cholocation sounds, which simulated echoes from sonar targets. Both tasks u tilized a single-channel electronic target simulator and tested the bat's i n a two-alternative forced choice procedure. The results of this study demo nstrate changes in the features of the FM bats' sonar sounds with echolocat ion task demands, lending support to the notion that this animal actively c ontrols the echo information that guides its behavior. (C) 2000 Acoustical Society of America. [S0001-4966(00)06103-3].