Song choice in juvenile zebra finches (Taeniopygia guttata)

Abstract

Past studies of zebra finch song development have revealed conflicting predictors of song choice. This study sought to clarify the qualities of (1) the relationship between the chick and tutor and (2) the behavior of the tutor that might affect song choice by the pupil. The study subjects were born and raised in an aviary where the free social interactions of all individuals in the colony were possible. A cross-fostering design was used within the aviary, so that chicks would not only have exposure to the male that raised him, but also to his genetic father (if different than his rearing father) and to several other adult males. The results were surprising. (1) Chicks cross-fostered to nests within the same aviary as their parents' nest were found to recognize and learn their genetic father's song after fledging despite their lack of exposure to him in the nest. Also, (2) simply being a father or a mated male was not a significant predictor of song tutor choice, while the quality of being an attentive father or mate was. On a less surprising note, (3) the male that raised the chick was copied more than other adult males, as was the genetic father. Additionally, (4) brothers raised together inhibited song similarity in one another, which supports the finding of "fraternal inhibition" found by Tchernichovski and Nottebohm (1998). Two song copying measures were used and compared, and cross-correlation was used to validate the methods of quantifying song copying behavior. Extensive behaviorial observations of the colony members were made in order to gain a reliable measure of the behavioral tendencies of the tutors for use as predictors of song choice. When given a choice that begins to approach the degree of choice in the wild, juvenile zebra finches revealed the sensitivity of their genetic template to their father's song and the importance of the behavior of the song tutor for choosing song.