EARLY EXPERIENCE CAN MODIFY SINGING STYLES - EVIDENCE FROM EXPERIMENTS WITH NIGHTINGALES, LUSCINIA-MEGARHYNCHOS

The way in which song repertoires are performed, though modifiable by degree, has been considered to be a species-typical trait. This study examines whether it can be influenced by learning. During their early sensitive phase of song acquisition, hand-raised nightingales were tutored with strings of master song-types in which song-types were arranged in different bout structures. In one design (control), strings with the species-typical song-type sequencing were presented (i.e. versatile bout structure, no song-type repetitions: A,B,C...). In the other design song-types were arranged in a bout structure atypical for the species (i.e. song-type repetitions: D,D,D,... E,E,E...). Subjects were exposed either to both designs (experimental group) or to the versatile design only (control group). The crystallized singing of experimental subjects at 11 months revealed that they had acquired serial information about the tutored strings. Song-types acquired from the repetitive tutoring design were repeated significantly more often than those acquired from the versatile design. Furthermore, the bout length of song-type renditions showed a relationship to the bout length of the respective master song-types upon presentation. The results provide evidence for an acquisition of repertoire performance programmes through learning, which may modulate species-typical singing styles. © 1991 The Association for the Study of Animal Behaviour.