Integrating patterns of thermal tolerance and phenotypic plasticity with population genetics to improve understanding of vulnerability to warming in a widespread copepod
Integrating patterns of thermal tolerance and phenotypic plasticity with population genetics to improve understanding of vulnerability to warming in a widespread copepod
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将耐热性和表型可塑性模式与群体遗传学相结合，以提高对广泛分布的桡足类变暖脆弱性的了解
DOI：
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发表时间：
2019
期刊：
影响因子：
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通讯作者：
H. Dam
中科院分区：
文献类型：
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作者：
M. Sasaki;H. Dam
人口对变暖的脆弱性的差异是由热适应的空间格局来定义的。这些模式可能是由空间环境梯度上的自然选择驱动的，但也可能是由基因流塑造的，特别是在具有高扩散潜力的海洋类群中。理解和预测生物对气候变暖的反应需要解开选择和基因流动的对立效应。我们开始记录遗传分歧的耐热性和发育表型可塑性。从佛罗里达群岛到北方新玩法、加拿大（跨越20多个纬度）的一个大的温度梯度的地点收集了广泛分布的桡足类Acartia tonsa的10个种群。从常见的花园实验的热性能曲线显示，在采样范围的极端，热耐受性增加，在低纬度和高纬度地区减少当地的适应。在表型可塑性中观察到相反的模式，在高纬度地区最强。然而，在大部分采样范围内，我们观察到热性能曲线明显缺乏差异。为了研究这种缺乏分歧是选择的结果，一个通才的性能曲线或基因流的约束，我们分析了细胞色素氧化酶I mtDNA序列，揭示了丰富的遗传多样性和广泛分布的单倍型。然而，在遗传分支的热性能的强烈分歧，表明热适应的步伐可以相对较快。实验室生理实验和遗传数据的结合表明，基因流限制了热性能曲线的分化。基因流动和选择之间的这种平衡对气候变暖的脆弱性模式有影响。考虑到遗传分化和表型可塑性，我们的研究结果表明，当地的适应并没有增加对变暖的脆弱性，低纬度人口一般可能更容易受到预测的温度变化在未来世纪。
Differences in population vulnerability to warming are defined by spatial patterns in thermal adaptation. These patterns may be driven by natural selection over spatial environmental gradients, but can also be shaped by gene flow, especially in marine taxa with high dispersal potential. Understanding and predicting organismal responses to warming requires disentangling the opposing effects of selection and gene flow. We begin by documenting genetic divergence of thermal tolerance and developmental phenotypic plasticity. Ten populations of the widespread copepod Acartia tonsa were collected from sites across a large thermal gradient, ranging from the Florida Keys to Northern New Brunswick, Canada (spanning over 20 degrees latitude). Thermal performance curves from common garden experiments revealed local adaptation at the sampling range extremes, with thermal tolerance increasing at low latitudes and decreasing at high latitudes. The opposite pattern was observed in phenotypic plasticity, which was strongest at high latitudes. Over a large portion of the sampled range, however, we observed a remarkable lack of differentiation of thermal performance curves. To examine whether this lack of divergence is the result of selection for a generalist performance curve or constraint by gene flow, we analyzed cytochrome oxidase I mtDNA sequences, which revealed abundant genetic diversity and widely-distributed haplotypes. Strong divergence in thermal performance within genetic clades, however, suggests that the pace of thermal adaptation can be relatively rapid. The combined insight from the laboratory physiological experiments and genetic data indicate that gene flow constrains differentiation of thermal performance curves. This balance between gene flow and selection has implications for patterns of vulnerability to warming. Taking both genetic differentiation and phenotypic plasticity into account, our results suggest that local adaptation does not increase vulnerability to warming, and that low latitude populations in general may be more vulnerable to predicted temperature change over the next century.
影响因子：
30.7
作者：
Torda, Gergely;Donelson, Jennifer M.;Munday, Philip L.
通讯作者：
Munday, Philip L.
影响因子：
2.5
作者：
L. Plough;C. Fitzgerald;A. Plummer;J. Pierson
通讯作者：
L. Plough;C. Fitzgerald;A. Plummer;J. Pierson