Host-parasite coevolutionary arms races give way to fluctuating selection
Host-parasite coevolutionary arms races give way to fluctuating selection
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DOI：
10.1111/j.1461-0248.2011.01624.x
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发表时间：
2011-07-01
期刊：
影响因子：
8.8
通讯作者：
Buckling, Angus
中科院分区：
文献类型：
--
作者：
Hall, Alex R.;Scanlan, Pauline D.;Buckling, Angus
宿主-寄生虫共同进化是生物多样性和寄生虫毒力的关键驱动力，但其影响取决于随着时间的推移共同进化动力学的性质。我们使用了荧光假单胞菌SBW 25和寄生噬菌体SBW 25 Phi 2的共同进化群体的表型数据，以及噬菌体尾纤维基因（涉及感染性进化）的遗传数据，以表明军备竞赛动态，典型的短期研究，随着时间的推移而减速。我们将这种影响归因于随着感染性和耐药性的增加，细菌和细菌的通用性成本增加。相比之下，随着时间的推移，对个体宿主和寄生虫基因型的波动选择得以维持，对寄生虫和宿主种群的表型特性变得越来越重要。鉴于许多其他系统都报告了通才的成本，军备竞赛通常可能会让位于对抗性共同进化种群中的波动选择。
Host-parasite coevolution is a key driver of biological diversity and parasite virulence, but its effects depend on the nature of coevolutionary dynamics over time. We used phenotypic data from coevolving populations of the bacterium Pseudomonas fluorescens SBW25 and parasitic phage SBW25 Phi 2, and genetic data from the phage tail fibre gene (implicated in infectivity evolution) to show that arms race dynamics, typical of short-term studies, decelerate over time. We attribute this effect to increasing costs of generalism for phages and bacteria with increasing infectivity and resistance. By contrast, fluctuating selection on individual host and parasite genotypes was maintained over time, becoming increasingly important for the phenotypic properties of parasite and host populations. Given that costs of generalism are reported for many other systems, arms races may generally give way to fluctuating selection in antagonistically coevolving populations.