Data from: Convergent evolution of social hybridogenesis in Messor harvester ants

Sexual reproduction generally requires no more than two partners. Here, we show convergent evolution of social hybridogenesis, a reproductive system requiring three reproductive partners in harvester ants. In this unorthodox reproductive system, two distinct genetic lineages live in sympatry and queens have to mate with males of their own lineage to produce queens along with males of the alternative lineage to produce workers. Using a large transcriptomic data set of nine species, we show that social hybridogenesis evolved at least three times independently in the genus Messor. Moreover, a study of 13 populations of Messor barbarus revealed that this mode of reproduction is fixed in the whole range of this ecologically dominant species. Finally, we show that workers can produce males carrying genes of the two genetic lineages, raising the possibility of rare gene flow between lineages contributing to the long-term maintenance of pairs of interdependent lineages. These results emphasize the evolutionary importance of social hybridogenesis, a major transition possibly linked to the peculiar ecology of harvester ants.

有性生殖通常仅需不超过两个交配伙伴。本研究揭示了社会杂交生殖（social hybridogenesis）的趋同演化——这是一种在收获蚁中需要三个生殖伙伴的特殊生殖系统。在这一非常规生殖模式中，两个截然不同的遗传谱系（genetic lineage）同域共存：蚁后必须与同谱系的雄蚁交配以产生新的蚁后，同时与另一谱系的雄蚁交配以产生工蚁。本研究通过对9个物种的大规模转录组数据集（transcriptomic dataset）分析，证实社会杂交生殖在收获蚁属（Messor）中至少独立演化了三次。此外，对13个野蛮收获蚁（Messor barbarus）种群的研究显示，该生殖模式在这一生态优势物种的整个分布范围内均稳定存在。最后，本研究证实工蚁可产生携带两个遗传谱系基因的雄蚁，这表明谱系间存在罕见的基因流，而此类基因交流或有助于维持相互依存的谱系对的长期存续。上述研究结果凸显了社会杂交生殖的演化重要性——这一重大演化过渡事件或与收获蚁独特的生态特征密切相关。