EVOLUTION OF SONG CULTURE IN THE ZEBRA FINCH

摘要

Similar to humans, juvenile songbirds learn their vocal repertoire by imitatingadult individuals. When raised in social and acoustic isolation, birds can stillsing, but they produce a highly abnormal song. What happens when such anabnormal song is culturally transmitted over generations? To examine thisquestion we placed an isolate adult bird in a large sound box together withfemales (who do not sing) and allowed them to breed for a few generations,while recording audio and video so as to track the social interactions and singingbehavior. We found that the juveniles readily imitated their father's isolate song,and yet, small but systematic variations in vocal performance accumulated overgenerations such that the third generation of learners already sang normal zebrafinch song. We investigated this cultural evolution process.