Why do hybrids turn down sex?
Why do hybrids turn down sex?
复制标题
为什么混血儿会拒绝性行为？
DOI：
10.1093/evolut/qpad129
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发表时间：
2023
期刊：
影响因子：
3.3
通讯作者：
Chapman, ed., Tracey
中科院分区：
文献类型：
--
作者：
Fyon, Frédéric;Berbel-Filho, Waldir Miron;Schlupp, Ingo;Wild, Geoff;Úbeda, Francisco;Orive, ed., Maria E.;Chapman, ed., Tracey
无性繁殖是原核生物的祖先。真核生物向性的转变是生命史上的重大转变之一。几十年来，对真核生物性别维持的研究引起了人们极大的兴趣，并且仍然是进化生物学最突出的问题之一。许多无性繁殖物种都是杂交起源的观察结果使一些人提出，杂交物种中的无性繁殖是由于两个亲本物种基因组之间不相容而导致有性过程受到干扰的结果。然而，在某些情况下，在实验室中未能产生无性 F1 可能表明这种机制并不是杂交物种无性化的唯一途径。在这里，我们提出了一个数学模型，并提出了一种替代的、适应性的途径，用于从以前的有性杂交进化为无性。在一些生殖改变下，我们发现无性生殖可以进化以挽救杂交后代的繁殖。重要的是，我们强调，当不相容性仅影响精子和卵子基因组的融合时，无性生殖的两个特征，即未减少的减数分裂和不合并精子原核的胚胎发生的启动，可以单独进化，极大地促进整体进化路线。总而言之，我们的结果为无性和杂交之间的联系提供了另一种可能互补的解释。
Asexual reproduction is ancestral in prokaryotes; the switch to sexuality in eukaryotes is one of the major transitions in the history of life. The study of the maintenance of sex in eukaryotes has raised considerable interest for decades and is still one of evolutionary biology’s most prominent question. The observation that many asexual species are of hybrid origin has led some to propose that asexuality in hybrids results from sexual processes being disturbed because of incompatibilities between the two parental species’ genomes. However, in some cases, failure to produce asexual F1s in the lab may indicate that this mechanism is not the only road to asexuality in hybrid species. Here, we present a mathematical model and propose an alternative, adaptive route for the evolution of asexuality from previously sexual hybrids. Under some reproductive alterations, we show that asexuality can evolve to rescue hybrids’ reproduction. Importantly, we highlight that when incompatibilities only affect the fusion of sperm and egg’s genomes, the two traits that characterize asexuality, namely unreduced meiosis and the initiation of embryogenesis without the incorporation of the sperm’s pronucleus, can evolve separately, greatly facilitating the overall evolutionary route. Taken together, our results provide an alternative, potentially complementary explanation for the link between asexuality and hybridization.