Freeberg Todd M, King Andrew P, West Meredith J
Department of Biology, Indiana University, IN, USA.
J Comp Psychol. 2008 Nov;122(4):437-40. doi: 10.1037/a0013408.
Increased understanding of geographic variation in courtship behavior in animal species can provide insight into the ways behavior may influence evolutionary change. Here, the relationship of geographic variation in courtship behavior to reproductive outcomes was tested in two distant and behaviorally distinct populations of brown-headed cowbirds, Molothrus ater, by comparing rates of copulation and egg production. Females from an Indiana (IN) population and a South Dakota (SD) population were housed in aviaries with males from either their own population (INsame and SDsame) or the other population (INmix and SDmix). Over the breeding season, INsame females exhibited higher rates of copulation and egg production compared with INmix females, but no differences were detected between SDsame and SDmix females. The data suggest that behavioral differences between IN and SD cowbirds are the likely cause of lower egg production in the INmix females.
对动物物种求偶行为地理变异的深入了解，有助于洞察行为可能影响进化变化的方式。在此，通过比较交配率和产蛋率，在两个地理距离较远且行为特征不同的褐头牛鹂种群中，测试了求偶行为的地理变异与繁殖结果之间的关系。来自印第安纳州（IN）种群和南达科他州（SD）种群的雌性褐头牛鹂，被安置在鸟舍中，与来自它们自己种群（INsame和SDsame）或另一个种群（INmix和SDmix）的雄性褐头牛鹂在一起。在繁殖季节，与INmix雌性相比，INsame雌性表现出更高的交配率和产蛋率，但在SDsame和SDmix雌性之间未检测到差异。数据表明，IN和SD褐头牛鹂之间的行为差异可能是INmix雌性产蛋率较低的原因。
