Kuhn A, Bauman D, Darras H, Aron S
Evolutionary Biology and Ecology, Université Libre de Bruxelles, Brussels, Belgium.
Laboratoire d'Écologie Végétale et Biogéochimie, Université Libre de Bruxelles, Brussels, Belgium.
Heredity (Edinb). 2017 Oct;119(4):207-213. doi: 10.1038/hdy.2017.34. Epub 2017 Jun 21.
Reproduction and dispersal are key aspects of species life history that influence spatial genetic structure in populations. Several ant species in the genus Cataglyphis have evolved a unique breeding system in which new reproductives (that is, queens and males) are produced asexually by parthenogenesis; in contrast, non-reproductives (that is, workers) are produced via sexual reproduction by mates from distinct genetic lineages. We investigated how these two coexisting reproductive methods affect population-level spatial genetic structure using the ant Cataglyphis mauritanica as a model. We obtained genotypes for queens and their male mates from 338 colonies, and we found that the two lineages present in the study population occurred with equal frequency. Furthermore, analysis of spatial genetic structure revealed strong sex-biased dispersal. Because queens were produced by parthenogenesis and because they dispersed over short distances, there was an extreme level of spatial structuring: a mosaic of patches composed of clonal queens was formed. Males, on the other hand, dispersed over several hundred metres and, thus, across patches, ensuring successful interlineage mating.
繁殖和扩散是物种生活史的关键方面，会影响种群的空间遗传结构。撒哈拉银蚁属的几种蚂蚁已经进化出一种独特的繁殖系统，其中新的繁殖个体（即蚁后和雄蚁）通过孤雌生殖无性产生；相比之下，非繁殖个体（即工蚁）则是由来自不同遗传谱系的配偶通过有性生殖产生。我们以毛里塔尼亚撒哈拉银蚁为模型，研究了这两种共存的繁殖方式如何影响种群水平的空间遗传结构。我们获得了338个蚁群中蚁后及其雄蚁配偶的基因型，发现研究种群中存在的两个谱系出现频率相等。此外，对空间遗传结构的分析揭示了强烈的性别偏向扩散。由于蚁后是通过孤雌生殖产生的，并且它们的扩散距离较短，因此存在极端的空间结构：形成了由克隆蚁后组成的斑块镶嵌体。另一方面，雄蚁扩散了数百米，从而跨越了斑块，确保了不同谱系间的成功交配。
