Laboratory of Aquatic Ecology and Evolutionary Biology, Katholieke Universiteit Leuven, Ch. Deberiotstraat 32, 3000 Leuven, Belgium.
Evolution. 2011 Sep;65(9):2681-91. doi: 10.1111/j.1558-5646.2011.01331.x. Epub 2011 May 19.
Although natural populations may evolve resistance to anthropogenic stressors such as pollutants, this evolved resistance may carry costs. Using an experimental evolution approach, we exposed different Daphnia magna populations in outdoor containers to the carbamate pesticide carbaryl and control conditions, and assessed the resulting populations for both their resistance to carbaryl as well as their susceptibility to infection by the widespread bacterial microparasite Pasteuria ramosa. Our results show that carbaryl selection led to rapid evolution of carbaryl resistance with seemingly no cost when assessed in a benign environment. However, carbaryl-resistant populations were more susceptible to parasite infection than control populations. Exposure to both stressors reveals a synergistic effect on sterilization rate by P. ramosa, but this synergism did not evolve under pesticide selection. Assessing costs of rapid adaptive evolution to anthropogenic stress in a semi-natural context may be crucial to avoid too optimistic predictions for the fitness of the evolving populations.
尽管自然种群可能会进化出对人为压力（如污染物）的抗性，但这种进化出的抗性可能会带来代价。我们采用实验进化的方法，将不同的大型溞种群暴露在户外容器中的氨基甲酸酯类杀虫剂涕灭威和对照条件下，并评估了由此产生的种群对涕灭威的抗性以及对广泛存在的细菌微寄生虫粘孢子虫的易感性。我们的结果表明，在良性环境下，涕灭威选择导致了快速进化出的抗性，而没有明显的代价。然而，与对照种群相比，对杀虫剂有抗性的种群更容易受到寄生虫感染。暴露于两种胁迫因子下，通过粘孢子虫导致的杀菌率呈现出协同效应，但这种协同作用在杀虫剂选择下并没有进化。在半自然环境中评估对人为压力的快速适应性进化的代价，可能对于避免对进化种群的适应性过于乐观的预测至关重要。
