Data from: Social and extra-pair mating in relation to MHC variation in common yellowthroats

Females are thought to gain better quality genes for their offspring by mating with particular males. Genes of the major histocompatibility complex (MHC) play a critical role in adaptive immunity, and many studies have examined female mate choice in relation to MHC variation. In common yellowthroats, females prefer males that have larger facial masks, an ornament associated with MHC variation, immune function and condition. Here we also tested whether mating patterns are directly correlated with MHC diversity or similarity. Using pyrosequencing, we found that the presence of extra-pair young in the brood was not related to male MHC diversity or similarity between the female and her within-pair mate. Furthermore, extra-pair sires did not differ from males they cuckolded. MHC diversity is extremely high in this species, and it may limit the ability of females to assess MHC variation in males. Thus, mating may be based on ornaments, such as mask size, which are better indicators of overall male health and genetic quality.

学界普遍认为，雌性个体通过与特定雄性交配，可为后代获取更优质的基因。主要组织相容性复合体（major histocompatibility complex，MHC）的相关基因在适应性免疫中发挥关键作用，既往诸多研究均探讨了雌性配偶选择与MHC变异的关联。在普通黄喉地莺中，雌性更偏爱拥有更大面部面罩的雄性——这类装饰性特征与MHC变异、免疫功能及身体状况密切相关。本研究同时检验了交配模式是否与MHC多样性或雌雄个体间的MHC相似性直接相关。通过焦磷酸测序技术，我们发现窝内婚外子代的存在与否，与雄性的MHC多样性，或是雌性与其配偶雄性之间的MHC相似性均无关联。此外，婚外父本与被其篡夺配偶地位的雄性之间，在MHC特征上并无显著差异。该物种的MHC多样性极高，这可能限制了雌性评估雄性MHC变异的能力。因此，雌性的交配选择或基于诸如面部面罩大小这类装饰性特征——这类特征可更好地反映雄性整体健康状况与遗传品质。