Data from: The influence of social structure on brood survival and development in a socially polymorphic ant: insights from a cross-fostering experiment

Animal societies vary in the number of breeders per group, which affects many socially and ecologically relevant traits. In several social insect species, including our study species Formica selysi, the presence of either one or multiple reproducing females per colony is generally associated with differences in a suite of traits such as the body size of individuals. However, the proximate mechanisms and ontogenetic processes generating such differences between social structures are poorly known. Here, we cross-fostered eggs originating from single-queen (=monogynous) or multiple-queen (=polygynous) colonies into experimental groups of workers from each social structure to investigate whether differences in offspring survival, development time and body size are shaped by the genotype and/or pre-foster maternal effects present in the eggs, or by the social origin of the rearing workers. Eggs produced by polygynous queens were more likely to survive to adulthood than eggs from monogynous queens, regardless of the social origin of the rearing workers. However, brood from monogynous queens grew faster than brood from polygynous queens. The social origin of the rearing workers influenced the probability of brood survival, with workers from monogynous colonies rearing more brood to adulthood than workers from polygynous colonies. The social origin of eggs or rearing workers had no significant effect on the head size of the resulting workers in our standardized laboratory conditions. Overall, the social backgrounds of the parents and of the rearing workers appear to shape distinct survival and developmental traits of ant brood.

动物社会中，每一群组内的繁殖者数量存在差异，这会影响诸多与社会及生态相关的性状。在多种社会性昆虫物种中，包括本研究所用的塞氏蚁（Formica selysi），每个蚁群仅存在1只或多只繁殖雌性的社会结构，通常与个体体型等一系列性状的差异相关联。然而，学界对产生这类社会性结构差异的近因机制与个体发育过程仍知之甚少。本研究将来自单后制（monogynous）或多后制（polygynous）蚁群的卵，交叉抚育至两种社会性结构的工蜂实验群中，以此探究子代存活率、发育时长与体型的差异，究竟由卵携带的基因型及/或抚育前母体效应所决定，还是由抚育工蜂的社会来源所塑造。无论抚育工蜂的社会来源如何，多后制蚁后所产的卵发育至成虫的存活率均高于单后制蚁后所产的卵。但单后制蚁后所产的子代群发育速度快于多后制蚁后的子代群。抚育工蜂的社会来源同样会影响子代群的存活率：单后制蚁群的工蜂抚育至成虫的子代群数量，多于多后制蚁群的工蜂。在本研究的标准化实验室条件下，卵的社会来源或抚育工蜂的来源，对子代工蜂的头部尺寸均无显著影响。综上，亲本与抚育工蜂的社会背景，似乎会分别塑造蚁类子代群不同的存活与发育性状。