Taillebois Laura, Sabatino Stephen, Manicki Aurélie, Daverat Françoise, Nachón David José, Lepais Olivier
ECOBIOP INRA Université de Pau et Pays de l'Adour Saint-Pée-sur-Nivelle France.
CIBIO-InBIO Universidade do Porto Vairão Portugal.
Evol Appl. 2019 Nov 13;13(4):636-651. doi: 10.1111/eva.12889. eCollection 2020 Apr.
Hybridization dynamics between co-occurring species in environments where human-mediated changes take place are important to quantify for furthering our understanding of human impacts on species evolution and for informing management. The allis shad (Linnaeus, 1758) and twaite shad (Lacépède, 1803), two clupeids sister species, have been severely impacted by human activities across Europe. The shrinkage of distribution range along with the decline of the remaining populations' abundance threatens its persistence. The main objective was to evaluate the extent of hybridization and introgression between those interacting species. We developed a set of 77 species-specific SNP loci that allowed a better resolution than morphological traits as they enabled the detection of hybrids up to the third generation. Variable rates of contemporary hybridization and introgression patterns were detected in 12 studied sites across the French Atlantic coast. Mitochondrial markers revealed a cyto-nuclear discordance almost invariably involving individuals with an mitochondrial DNA and provided evidence of historical asymmetric introgression. Overall, contemporary and historical introgression revealed by nuclear and mitochondrial markers strongly suggests that a transfer of genes occurs from toward genome since at least four generations. Moreover, the outcomes of introgression greatly depend on the catchments where local processes are thought to occur. Undoubtedly, interspecific interaction and gene flow should not be overlooked when considering the management of those species.
在发生人类介导变化的环境中，共存物种之间的杂交动态对于深化我们对人类对物种进化影响的理解以及为管理提供信息而言，量化其情况很重要。西鲱（Linnaeus，1758年）和泰维特西鲱（Lacépède，1803年），这两种鲱科姊妹物种，在欧洲各地都受到了人类活动的严重影响。分布范围的缩小以及剩余种群数量的下降威胁到了它们的存续。主要目标是评估这些相互作用物种之间杂交和基因渗入的程度。我们开发了一组77个物种特异性单核苷酸多态性位点，与形态特征相比，它们能实现更好的分辨效果，因为它们能够检测出直至第三代的杂交种。在法国大西洋沿岸的12个研究地点检测到了当代杂交和基因渗入模式的不同速率。线粒体标记揭示了一种几乎总是涉及具有线粒体DNA个体的细胞核与细胞质不一致情况，并提供了历史上不对称基因渗入的证据。总体而言，核标记和线粒体标记所揭示的当代和历史基因渗入强烈表明，至少从四代以来就发生了从[物种A]基因组向[物种B]基因组的基因转移。此外，基因渗入的结果在很大程度上取决于被认为发生局部过程的集水区。毫无疑问，在考虑对这些物种的管理时，种间相互作用和基因流动不应被忽视。
