Genetic benefits of extreme sequential polyandry in a terrestrial-breeding frog

Sequential polyandry may evolve as an insurance mechanism to reduce the risk that females choose mates that are genetically inferior (intrinsic male quality hypothesis) or genetically incompatible (genetic incompatibility hypothesis). The prevalence of such indirect benefits remains controversial, however, because few studies have estimated the contributions of additive and non-additive sources of genetic variation to offspring fitness in species with sequential polyandry. Here, we use artificial fertilisation techniques combined with a cross-classified breeding design (North Carolina Type II) to simultaneously test the ‘good genes hypothesis’ and the ‘genetic incompatibility hypothesis’ in the brown toadlet (Pseudophryne bibronii); a terrestrial breeding species with extreme sequential polyandry. Our results revealed no significant additive or non-additive genetic effects on fertilisation success. Moreover, they revealed no significant additive genetic effects, but highly significant n...

逐次一妻多夫制（sequential polyandry）可能作为一种保障机制演化而来，用以降低雌性选择遗传质量低劣雄性（内在雄性质量假说，intrinsic male quality hypothesis）或遗传不相容雄性（遗传不相容假说，genetic incompatibility hypothesis）的风险。然而，这类间接收益的普遍性仍存在争议，因为鲜有研究在存在逐次一妻多夫制的物种类群中，估算加性与非加性遗传变异来源对子代适合度的贡献。本研究结合人工受精技术与交叉分类繁育设计（北卡罗来纳Ⅱ型，North Carolina Type II），在极端逐次一妻多夫的陆栖繁育物种棕澳蟾（Pseudophryne bibronii）中同时检验“优质基因假说（good genes hypothesis）”与“遗传不相容假说”。研究结果显示，受精成功率未受到显著的加性或非加性遗传效应影响；此外，结果未发现显著的加性遗传效应，但存在高度显著的n...