Genomic models predict successful coral adaptation if future ocean warming rates are reduced
Genomic models predict successful coral adaptation if future ocean warming rates are reduced
复制标题
DOI：
10.1126/sciadv.1701413
复制
发表时间：
2017-11-01
期刊：
影响因子：
13.6
通讯作者：
Palumbi, Stephen R.
中科院分区：
文献类型：
--
作者：
Bay, Rachael A.;Rose, Noah H.;Palumbi, Stephen R.
种群基因组调查表明，与气候相关的遗传变异在物种之间广泛存在，但它是否足以通过进化适应使种群得以持续存在却很少被量化。为了询问造礁珊瑚的快速适应是否能够跟上未来海洋变暖的步伐，我们测量了预测的温暖适应位点的遗传变异，并模拟了库克群岛拉罗汤加岛高纬度珊瑚种群的未来进化和持久性。在这个较冷、偏南的地区，存在与耐热性相关的等位基因，但频率较低。基于拉罗汤加海洋变暖预测的模拟显示，耐热性的快速演变导致种群在温和变暖情景下持续存在，这与低二氧化碳排放计划 RCP2.6 和 RCP4.5 一致。在更严重的情况下，RCP6.0和RCP8.5，适应速度不够快，不足以防止灭绝。对于基于较少数量的决定热耐受性的附加基因座的模型以及较高的种群增长率，种群适应速度更快。最后，通过移植耐热个体（每年 1 至 5%）加速迁移，加速了适应。这些结果表明，冷水珊瑚可以适应温暖的海洋，但仅限于国际排放控制造成的温和情况下。将基因组数据纳入物种对气候变化响应的模型中，为估计未来的适应过程提供了一种有前途的方法。
Population genomic surveys suggest that climate-associated genetic variation occurs widely across species, but whether it is sufficient to allow population persistence via evolutionary adaptation has seldom been quantified. To ask whether rapid adaptation in reef-building corals can keep pace with future ocean warming, we measured genetic variation at predicted warm-adapted loci and simulated future evolution and persistence in a high-latitude population of corals from Rarotonga, Cook Islands. Alleles associated with thermal tolerance were present but at low frequencies in this cooler, southerly locality. Simulations based on predicted ocean warming in Rarotonga showed rapid evolution of heat tolerance resulting in population persistence under mild warming scenarios consistent with low CO2 emission plans, RCP2.6 and RCP4.5. Under more severe scenarios, RCP6.0 and RCP8.5, adaptation was not rapid enough to prevent extinction. Population adaptation was faster for models based on smaller numbers of additive loci that determine thermal tolerance and for higher population growth rates. Finally, accelerated migration via transplantation of thermally tolerant individuals (1 to 5%/year) sped adaptation. These results show that cool-water corals can adapt to warmer oceans but only under mild scenarios resulting from international emissions controls. Incorporation of genomic data into models of species response to climate change offers a promising method for estimating future adaptive processes.