Data from: Early reproductive success in Drosophila males is dependent on maturity of the accessory gland

In a number of insect taxa, male sexual maturity is not always directly attained at adult eclosion. Sexual maturity is often defined behaviorally as mating success, or physiologically as the point when gametes are produced. Here, we show that the sexual maturation process in males is more complex than previously described and that a measure of maturity also needs to include post-mating traits. In many species mating success is tightly linked with size of the accessory gland (AG). The AG is the production site of a complex cocktail of proteins that are transferred to the female along with the sperm, and which impact on important functions for male reproductive success. Using Drosophila melanogaster we conducted comprehensive behavioral assays of several aspects of male reproductive fitness and demonstrated that the AG has to attain full maturity for males to reach full reproductive competence. We tested males from shortly after, and up to 6 days, post adult eclosion, and considered both pre- and post-copulatory traits. Young males are less likely to gain a mating and show significantly less courtship behavior. Young males that managed to obtain a mating however were inferior in many post-copulatory traits like sperm competitiveness and effectiveness in suppressing female remating. We monitored male AG development over the first 6 days after eclosion and found it to significantly increase in size over the entire period.在诸多昆虫类群中，雄性的性成熟并非总是在成虫羽化时直接达成。性成熟常被从行为学层面定义为交配成功，或从生理学层面定义为配子产生的节点。本研究表明，雄性的性成熟过程比此前描述的更为复杂，对成熟度的评估也需纳入交配后性状。在诸多物种中，交配成功率与附腺（accessory gland, AG）的大小紧密相关。附腺是一类复杂蛋白质混合物的合成场所，这类蛋白质会与精子一同被转移至雌性体内，并对雄性生殖成功的关键功能产生影响。本研究以黑腹果蝇（Drosophila melanogaster）为实验对象，对雄性生殖适合度的多个维度开展了全面的行为学检测，结果证实附腺必须完全成熟，雄性才能具备完整的生殖能力。我们测试了成虫羽化后不久至羽化后6天内的雄性个体，并同时考量了交配前与交配后性状。年轻雄性更难成功交配，且求偶行为显著更少。但即便成功完成交配的年轻雄性，在诸多交配后性状上也表现不佳，例如精子竞争力以及抑制雌性再次交配的能力。我们监测了羽化后前6天内雄性附腺的发育情况，发现其大小在整个监测周期内均显著增长。