Behavioural polymorphisms associated with morphs with a known genetic basis are interesting to study since they provide a model system to investigate the molecular basis of complex behaviours. White-throated sparrows are one of such rare models, presenting two morphologies and behavioural types, tan and white, caused by a chromosomal rearrangement. The behavioural differences have been mainly studied during reproduction, defining two morph-specific breeding strategies and different levels of aggression between morphs. Outside of the breeding season, the morphological differences are less apparent, morphs are more difficult to distinguish and the behavioural polymorphism is poorly understood. In this study, we caught wild individuals during the winter, determined their morph by genetic analysis, and analysed the differences in behaviour between morphs when encountering a novel object under standardized conditions in captivity. White morphs are more aggressive during reproduction; therefore, we expected them to be less affected by the presence of the novel object than tan morphs; animal personality research shows that more aggressive individuals are less affected by the presence of novel objects (i.e. neophilic). Contrary to our expectations, white morphs were more neophobic than tan morphs, and within morphs, males were more neophobic than females. Furthermore, white morph individuals and males of both morphs suffered greater weight loss during captivity compared to tan morphs and females, respectively, suggesting that the response to captivity-induced stress differs between morphs and between sexes. Finding behavioural differences between morphs not related to reproduction implies a broader impact of the effects of the chromosomal rearrangement on the behavioural polymorphism in this species.

中文翻译：

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越冬白喉麻雀, Zonotrichia albicollis 的行为多态性

与具有已知遗传基础的变形相关的行为多态性值得研究，因为它们提供了一个模型系统来研究复杂行为的分子基础。白喉麻雀是这种罕见的模型之一，呈现出两种形态和行为类型，棕褐色和白色，由染色体重排引起。主要在繁殖期间研究了行为差异，定义了两种特定于变体的育种策略和变体之间不同程度的攻击性。在繁殖季节之外，形态差异不太明显，变体更难区分，行为多态性也知之甚少。在这项研究中，我们在冬季捕获了野生个体，通过遗传分析确定了它们的形态，并分析了在囚禁的标准化条件下遇到新物体时变形之间行为的差异。白色变种在繁殖过程中更具攻击性；因此，我们预计它们比棕褐色变形受新物体存在的影响要小；动物性格研究表明，更具攻击性的个体受新物体（即新事物）存在的影响较小。与我们的预期相反，白色变种比棕褐色变体更怕新，在变体中，男性比女性更怕新。此外，与棕褐色变种和雌性相比，白色变种个体和两种变种的雄性在圈养期间体重减轻更大，这表明对圈养引起的压力的反应在变种之间和性别之间不同。