Same-sex partner preference in adult male zebra finch offspring raised in the absence of maternal care

An important component of mate choice is the sex of the potential partner, yet little is known about the factors that cause an individual to pair with the opposite sex. In the current study, we addressed the role of exposure to adult females during development in adult mate choice using a socially monogamous and biparental avian species, the zebra finch, Taeniopygia guttata. In our experimental set-up, zebra finch offspring were either raised in the presence of adult males and females in their aviaries (control) or in the absence of all adult females including their mothers (female-deprived). The female-deprived subjects were raised successfully by the male parents and showed no growth deficits compared to controls. When we tested partner preference of control and female-deprived subjects as adults, 57% of males that had been raised without females paired with each other. In contrast, 76% of male offspring that were raised with adults of both sexes paired with females. The most likely interpretation of this dramatic effect on pairing outcome is imprinting on adult males in the aviary in the absence of all adult females. These results thus suggest that sexual imprinting or some other form of social learning is a key developmental process for sexual partner preference in addition to preference for species and individual characteristics.