Data from: Reproductive sharing in relation to group and colony-level attributes in a cooperative breeding fish

The degree to which group members share reproduction is dictated by both within-group (e.g. group size and composition) and between-group (e.g. density and position of neighbours) characteristics. While many studies have investigated reproductive patterns within social groups, few have simultaneously explored how within-group and between-group social structures influence these patterns. Here, we investigated how group size and composition, along with territory density and location within the colony, influenced parentage in 36 wild groups of a colonial, cooperatively breeding fish Neolamprologus pulcher. Dominant males sired 76% of offspring in their group, while dominant females mothered 82% of offspring in their group. Subordinate reproduction was frequent, occurring in 47% of sampled groups. Subordinate males gained more paternity in groups located in high-density areas and in groups with many subordinate males. Dominant males and females in large groups and in groups with many reproductively mature subordinates had higher rates of within-group parentage loss, but only at the colony edge. Our study provides the first comprehensive quantification of reproductive sharing among groups of wild N. pulcher, a model species for the study of cooperation and social behaviour. Further, we demonstrate that the frequency of extra-pair parentage differs across small social and spatial scales.

群体成员共享繁殖的程度，由群体内部（如群体规模与组成）以及群体间（如邻体密度与所处位置）两类特征共同决定。尽管已有大量研究探讨了社会群体内部的繁殖模式，但鲜有研究同时探究群体内部与群体间的社会结构如何对这些繁殖模式产生影响。本研究以合作繁殖的集群栖居鱼类饰鳍新亮丽鲷（Neolamprologus pulcher）的36个野生群体为研究对象，分析了群体规模与组成、领地密度以及其在种群中的位置如何影响亲本归属格局。优势雄性可获得群体中76%的父权，而优势雌性则可获得群体内82%的母权。从属个体的繁殖行为十分常见，在47%的采样群体中均有发生。从属雄性在高密度区域的群体以及拥有较多从属雄性的群体中，可获得更多的父权份额。在群体规模较大，或是拥有较多生殖成熟从属个体的群体中，优势雌雄个体的群体内亲本份额流失率更高，但该现象仅存在于种群边缘的群体中。本研究首次对野生饰鳍新亮丽鲷（N. pulcher）群体间的繁殖共享情况进行了全面量化，该物种是研究合作行为与社会行为的经典模式物种。此外，本研究证实，配对外亲子关系的发生频率在较小的社会尺度与空间尺度上存在显著差异。