PUB - Publikationen an der Universität Bielefeld

Young zebra finch, Taeniopygia guttata castanotis, males were raised by Bengalese finch, Lonchura striata, foster parents until day 35, 40 or 50 of age, respectively. Following isolation until day 100, about half of the birds in each age group were tested for their preference for Bengalese or zebra finch females in two double-choice tests (pretests). After breeding experience with a conspecific female for 7 months, their sexual preferences were re-tested in two series of five double-choice tests (post-tests), one series 14 days after breeding experience, the other 7-12 months later. Preferences established during early development were changed by breeding experience. However, this change in preference was suppressed by preceding short phases of courtship experience with the foster parent species (during the pretests) after isolation. The same results were obtained by double-choice tests on the same birds 7-12 months later, demonstrating that the acquired preferences are quite stable. Large individual differences in the preferences of the birds may be caused by as yet unknown, subtle differences in rearing conditions. It is proposed that the preferences acquired during early development have to be stabilized by courtship experience. If the adequate object for courting is replaced by another one, a new preference may emerge. The extremely short time which is needed for consolidation may be explained by the high arousal level during pretests.