The Roles of Introgression and Climate Change in the Rise to Dominance of Acropora Corals
The Roles of Introgression and Climate Change in the Rise to Dominance of Acropora Corals
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DOI：
10.1016/j.cub.2018.08.061
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发表时间：
2018-11-05
期刊：
影响因子：
9.2
通讯作者：
Satoh, Noriyuki
中科院分区：
文献类型：
--
作者：
Mao, Yafei;Economo, Evan P.;Satoh, Noriyuki
造礁珊瑚为地球上最壮观、最多样化但日益受到威胁的生态系统之一提供了结构基础。现代印度-太平洋珊瑚礁以鹿角珊瑚属的物种为主，但与它们的多样化和上升到主导地位相关的进化和生态因素尚不清楚。最近关于进化辐射的工作证明了基因渗入和生态机会在促进多样化和生态成功方面的重要性。在这里，我们分析了五种鹿角珊瑚的基因组，以研究基因渗入和生态机会在鹿角珊瑚崛起中的作用。我们发现了以重大基因渗入事件为标志的历史证据以及跨物种的反复基因流。此外，我们发现拓扑与物种树不匹配的基因进化得更快，这表明基因渗入在传播适应性遗传变异中发挥着作用。人口统计分析表明，鹿角珊瑚谱系受益于上更新世气候驱动的大规模灭绝，这表明鹿角珊瑚利用了新的气候制度所带来的生态机会，有利于能够应对海平面快速变化的物种。总的来说，造礁珊瑚的基因组记录了由基因渗入和气候变化塑造的进化历史，这表明鹿角珊瑚是最容易受到压力源影响的珊瑚之一，这对于了解珊瑚礁如何追踪人类世即将发生的海平面快速变化可能至关重要。
Reef-building corals provide the structural basis for one of Earth's most spectacular and diverse-but increasingly threatened-ecosystems. Modern Indo-Pacific reefs are dominated by species of the staghorn coral genus Acropora, but the evolutionary and ecological factors associated with their diversification and rise to dominance are unclear. Recent work on evolutionary radiations has demonstrated the importance of introgression and ecological opportunity in promoting diversification and ecological success. Here, we analyze the genomes of five staghorn coral species to examine the roles of introgression and ecological opportunity in the rise to dominance of Acropora. We found evidence for a history marked by a major introgression event as well as recurrent gene flow across species. In addition, we found that genes with topologies mismatching the species tree are evolving faster, which is suggestive of a role for introgression in spreading adaptive genetic variation. Demographic analysis showed that Acropora lineages profited from climate-driven mass extinctions in the Plio-Pleistocene, indicating that Acropora exploited ecological opportunity opened by a new climatic regime favoring species that could cope with rapid sea-level changes. Collectively, the genomes of reef-building corals have recorded an evolutionary history shaped by introgression and climate change, suggesting that Acropora-among most vulnerable corals to stressors-may be critical for understanding how reefs track the impending rapid sea-level changes of the Anthropocene.