AUDITORY EXPERIENCE DOES NOT SHAPE SEXUAL PREFERENCES FOR SONGS IN FEMALE NORTHERN CARDINALS

Abstract

AbstractBird song is typically used by males to attract females. As a consequence of the vocal learning process, the acoustic morphology of male songs shows marked geographic variation. Whether females use variation in male songs to choose mates has been controversial (reviewed by Catchpole & Slater, 1995). In some species, the song types that females produce when treated hormonally have been considered to be the song types they prefer in the context of mate choice. To examine this notion, I investigated the song type preferences of female northern cardinals (Cardinalis cardinalis) using a more direct measure, copulation solicitation display. Unlike females of many other species of songbirds in the Temperate zone, female cardinals naturally develop songs by imitating adults just as males do, allowing direct identification of when and what song types are memorized by females for vocal production. I sought to determine if the memory trace formed for vocal performance is identical with the memory trace that guides song type preference in a sexual context, and whether females truly form any song type preference based on auditory experience during the first year of their lives. To address these questions, audio-video playback experiments were carried out on captive-raised adult cardinals whose complete auditory history was known. The results showed that female cardinals did not come to prefer any song type based on experience; they responded equally to all conspecific song types. Thus, memory formed for vocal production in females is not equal to song type preferred in sexual context. The results suggest that variation in song types is not important for mate choice in cardinals.