Data from: Sperm morphology, sperm motility and paternity success in the bluethroat (Luscinia svecica)

Postcopulatory sexual selection may select for male primary sexual characteristics like sperm morphology and sperm motility, through sperm competition or cryptic female choice. However, how such characteristics influence male fertilization success remains poorly understood. In this study, we investigate possible correlations between sperm characteristics and paternity success in the socially monogamous bluethroat (Luscinia svecica svecica), predicting that sperm length and sperm swimming speed is positively correlated with paternity success. In total, 25 % (15/61) of broods contained extra-pair offspring and 10 % (33/315) of the offspring were sired by extra-pair males. Paternity success did not correlate significantly with sperm morphology or any aspects of sperm motility. Furthermore, sperm morphology and sperm motility did not correlate significantly with male morphological characters that previously have been shown to be associated with paternity success. Thus, the sperm characteristics investigated here do not appear to be strong predictors of paternity success in bluethroats.交配后性选择可通过精子竞争或隐秘雌性选择，对雄性的初级性征（如精子形态、精子运动能力）进行筛选。然而，此类特征如何影响雄性父权成功率，目前仍不甚明晰。本研究以社会一夫一妻制的蓝喉歌鸲（Luscinia svecica svecica）为研究对象，探讨精子特征与父权成功率之间的潜在关联，并提出预测：精子长度与精子游动速度与父权成功率呈正相关。本研究共统计61个繁殖巢，其中25%（15/61）的巢中存在额外配对后代；共纳入315个子代个体，其中10%（33/315）的子代由额外配对雄性育成。分析结果显示，父权成功率与精子形态及精子运动能力的各维度均无显著相关性。此外，精子形态与精子运动能力，也与此前研究证实与父权成功率相关的雄性形态特征无显著关联。综上，本研究所考察的精子特征，似乎并不能作为蓝喉歌鸲父权成功率的有效预测因子。