The use of multiple pesticides or drugs can lead to a simultaneous selection pressure for resistance alleles at different loci. Models of resistance evolution focus on how this can delay the spread of resistance through a population, but often neglect how this can also reduce the probability that a resistance allele spreads. This neglected factor has been studied in a parallel literature as selective interference. Models of interference use alternative constructions of fitness, where selection coefficients from different loci either add or multiply. Although these are equivalent under weak selection, the two constructions make alternative predictions under the strong selection that characterizes resistance evolution. Here, simulations are used to examine the effects of interference on the probability of fixation and time to fixation of a new and strongly beneficial mutation in the presence of another strongly beneficial allele with variable starting frequency. The results from simulations show a complicated pattern of effects. The key result is that, under multiplicativity, the presence of the strongly beneficial allele leads to a small reduction in the probability of fixation for the new beneficial mutation up to ~10%, and a negligible increase in the average time to fixation up to ~2%, whereas under additivity, the effect is more substantial at up to ~50% for the probability of fixation and ~100% for the average time to fixation. Consequently, the effect of interference is only an important feature of resistance evolution under additivity. Current evidence from studies of experimental evolution provides widespread support for the basic features of additivity, which suggests that interference may afford resistance a different pattern of evolution than other adaptations: rather than the gradual and simultaneous selection of many alleles with small effects, the rapid evolution of resistance may involve the sequential selection of alleles with large effects.

中文翻译：

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选择性干扰替代模型下的电阻演变。

多种杀虫剂或药物的使用会导致对不同位点的抗性等位基因同时选择压力。抗药性进化模型侧重于这如何延缓抗药性在人群中的传播，但往往忽略这也可以降低抗性等位基因传播的可能性。这一被忽视的因素已在平行文献中作为选择性干扰进行了研究。干扰模型使用适应度的替代结构，其中来自不同位点的选择系数相加或相乘。尽管这些在弱选择下是等价的，但是这两种结构在表征抗性进化的强选择下做出了不同的预测。这里，模拟用于检查在另一个具有可变起始频率的强有益等位基因存在的情况下，干扰对固定概率和新的强有益突变的固定时间的影响。模拟结果显示出复杂的效果模式。关键结果是，在多重性下，强有益等位基因的存在导致新的有益突变的固定概率小幅降低至约 10%，而平均固定时间的增加可忽略不计至约2%，而在可加性下，固定概率的效果更显着，高达约 50%，平均固定时间约 100%。因此，干扰的影响只是可加性下电阻演化的一个重要特征。