Genetic mixing facilitates adaptation to a novel environmental constraint
Genetic mixing facilitates adaptation to a novel environmental constraint
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DOI：
10.1111/een.13242
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发表时间：
2023-04-06
影响因子：
2.2
通讯作者：
Hufbauer, Ruth A.
中科院分区：
文献类型：
--
作者：
Durkee, Lily F.;Olazcuaga, Laure;Hufbauer, Ruth A.
气候变化会影响季节的长度和时间，进而改变昆虫完成生命周期和成功繁殖的时间。来自遗传不同种群的个体之间的种内杂交或混合可以增强经历环境挑战的种群的适应性。混合可以特别有利于可能具有高遗传负荷的小型和孤立群体，通过掩盖有害等位基因，从而立即增加适应性，并且还通过增加可用于适应性进化的遗传变异。为了评估混合物对暴露于新的生命周期限制的种群的影响，我们使用赤拟谷盗作为模型系统。不同的实验室谱系被隔离或混合在一起以创建包含 1-4 个谱系的群体。然后，我们将混合种群与 1 谱系种群的适应性进行了比较，同时将它们缩短了三代的世代时间。混合后两代后不影响健康度。相比之下，在第三代中，混合种群的适应度明显高于 1 谱系种群。混合种群适应性增加的时间表明，实验种群对新的环境限制发生了适应。我们的研究强调了混合物对于促进快速适应季节性变化以及更广泛的环境变化的重要性。
Climate change can affect the length and timing of seasons, which in turn can alter the time available for insects to complete their life cycles and successfully reproduce. Intraspecific hybridization between individuals from genetically distinct populations, or admixture, can boost fitness in populations experiencing environmental challenges. Admixture can particularly benefit small and isolated populations that may have high genetic load by masking deleterious alleles, thereby immediately increasing fitness, and also by increasing the genetic variation available for adaptive evolution. To evaluate the effects of admixture on populations exposed to a novel life cycle constraint, we used the red flour beetle, Tribolium castaneum, as a model system. Distinct laboratory lineages were kept isolated or mixed together to create populations containing 1-4 lineages. We then compared the fitness of admixed populations to 1-lineage populations while subjecting them to a shortened generation time for three generations. Admixture did not influence fitness after two generations. In contrast, in the third generation, admixed populations had significantly greater fitness compared with 1-lineage populations. The timing of the increase in fitness for the admixed populations suggests that adaptation to the novel environmental constraint occurred in the experimental populations. Our study highlights the importance of admixture for facilitating rapid adaptation to changes in seasonality, and more broadly to environmental change.