LOEWE-Centre for Translational Biodiversity Genomics (LOEWE-TBG), Senckenberg Nature Research Society, 60325 Frankfurt am Main, Germany.
Department of Zoology and Animal Cell Biology, University of the Basque Country (UPV-EHU), 01006 Vitoria-Gasteiz, Spain.
Philos Trans R Soc Lond B Biol Sci. 2021 May 24;376(1825):20200156. doi: 10.1098/rstb.2020.0156. Epub 2021 Apr 5.
Despite the global biodiversity of terrestrial gastropods and their ecological and economic importance, the genomic basis of ecological adaptation and speciation in land snail taxa is still largely unknown. Here, we combined whole-genome re-sequencing with population genomics to evaluate the historical demography and the speciation process of two closely related species of land snails from western Europe, and . Historical demographic analysis indicated fluctuations in the size of ancestral populations, probably driven by Pleistocene climatic fluctuations. Although the current population distributions of both species do not overlap, our approximate Bayesian computation model selection approach on several speciation scenarios suggested that gene flow has occurred throughout the divergence process until recently. Positively selected genes diverging early in the process were associated with intragenomic and cyto-nuclear incompatibilities, respectively, potentially fostering reproductive isolation as well as ecological divergence. Our results suggested that the speciation between species entails complex processes involving both gene flow and ecological speciation, and that further research based on whole-genome data can provide valuable understanding on species divergence. This article is part of the Theo Murphy meeting issue 'Molluscan genomics: broad insights and future directions for a neglected phylum'.
尽管陆生腹足动物在全球范围内具有生物多样性，而且它们在生态和经济方面都很重要，但陆地蜗牛类群的生态适应和物种形成的基因组基础在很大程度上仍然未知。在这里，我们结合全基因组重测序和群体基因组学来评估来自西欧的两种密切相关的陆地蜗牛物种和 的历史人口动态和物种形成过程。历史人口动态分析表明，祖先种群的大小存在波动，这可能是由更新世气候波动驱动的。尽管这两个物种的当前种群分布没有重叠，但我们对几个物种形成情景的近似贝叶斯计算模型选择方法表明，直到最近，基因流一直在整个分化过程中发生。在早期分化的正选择基因分别与种内和细胞-核不相容性有关，这可能促进了生殖隔离以及生态分化。我们的研究结果表明，物种之间的物种形成涉及到涉及基因流和生态物种形成的复杂过程，并且基于全基因组数据的进一步研究可以提供对物种分化的有价值的理解。本文是 Theo Murphy 会议议题“软体动物基因组学：一个被忽视的门的广泛见解和未来方向”的一部分。
