Department of Ecology and Evolution, University of Lausanne, 1015 Lausanne, Switzerland.
Philos Trans R Soc Lond B Biol Sci. 2022 Aug;377(1856):20210196. doi: 10.1098/rstb.2021.0196. Epub 2022 Jun 13.
Species commonly exhibit alternative morphs, with individual fate being determined during development by either genetic factors, environmental cues or a combination thereof. Ants offer an interesting case study because many species are polymorphic in their social structure. Some colonies contain one queen while others contain many queens. This variation in queen number is generally associated with a suite of phenotypic and life-history traits, including mode of colony founding, queen lifespan, queen-worker dimorphism and colony size. The basis of this social polymorphism has been studied in five ant lineages, and remarkably social morph seems to be determined by a supergene in all cases. These 'social supergenes' tend to be large, having formed through serial inversions, and to comprise hundreds of linked genes. They have persisted over long evolutionary timescales, in multiple lineages following speciation events, and have spread between closely related species via introgression. Their evolutionary dynamics are unusually complex, combining recessive lethality, spatially variable selection, selfish genetic elements and non-random mating. Here, we synthesize the five cases of supergene-based social polymorphism in ants, highlighting interesting commonalities, idiosyncrasies and implications for the evolution of polymorphisms in general. This article is part of the theme issue 'Genomic architecture of supergenes: causes and evolutionary consequences'.
物种通常表现出替代形态，个体命运在发育过程中由遗传因素、环境线索或两者的组合决定。蚂蚁提供了一个有趣的案例研究，因为许多物种在其社会结构上具有多态性。一些蚁群只包含一只蚁后，而另一些则包含许多蚁后。蚁后数量的这种变化通常与一系列表型和生活史特征相关，包括蚁群的建立方式、蚁后的寿命、蚁后-工蚁二型性和蚁群大小。这种社会多态性的基础已经在五个蚂蚁谱系中进行了研究，令人惊讶的是，在所有情况下，社会形态似乎都是由一个超级基因决定的。这些“社会超级基因”往往很大，是通过连续倒位形成的，并且由数百个连锁基因组成。它们在长期的进化时间尺度上得以保留，在经历物种形成事件后的多个谱系中存在，并通过渐渗在亲缘关系密切的物种之间传播。它们的进化动态异常复杂，结合了隐性致死、空间可变选择、自私遗传元件和非随机交配。在这里，我们综合了蚂蚁中基于超级基因的社会多态性的五个案例，强调了有趣的共性、特殊性以及对多态性进化的一般意义。本文是主题为“超级基因的基因组结构：原因和进化后果”的特刊的一部分。
