Greenspoon Philip B, Mideo Nicole
Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada, M5S 3B2.
Evolution. 2017 Mar;71(3):747-755. doi: 10.1111/evo.13157. Epub 2017 Jan 5.
The theory that coevolving hosts and parasites create a fluctuating selective environment for one another (i.e., produce Red Queen dynamics) has deep roots in evolutionary biology; yet empirical evidence for Red Queen dynamics remains scarce. Fluctuating coevolutionary dynamics underpin the Red Queen hypothesis for the evolution of sex, as well as hypotheses explaining the persistence of genetic variation under sexual selection, local parasite adaptation, the evolution of mutation rate, and the evolution of nonrandom mating. Coevolutionary models that exhibit Red Queen dynamics typically assume that hosts and parasites encounter one another randomly. However, if related individuals aggregate into family groups or are clustered spatially, related hosts will be more likely to encounter parasites transmitted by genetically similar individuals. Using a model that incorporates familial parasite transmission, we show that a slight degree of familial parasite transmission is sufficient to halt coevolutionary fluctuations. Our results predict that evidence for Red Queen dynamics, and its evolutionary consequences, are most likely to be found in biological systems in which hosts and parasites mix mainly at random, and are less likely to be found in systems with familial aggregation. This presents a challenge to the Red Queen hypothesis and other hypotheses that depend on coevolutionary cycling.
共同进化的宿主和寄生虫为彼此创造了一个波动的选择环境（即产生红皇后动态）这一理论在进化生物学中有着深厚的根基；然而，红皇后动态的实证证据仍然稀少。波动的共同进化动态是性别进化的红皇后假说以及解释性选择下遗传变异的持续存在、局部寄生虫适应、突变率进化和非随机交配进化等假说的基础。表现出红皇后动态的共同进化模型通常假设宿主和寄生虫随机相遇。然而，如果相关个体聚集为家族群体或在空间上聚集，相关宿主将更有可能遇到由基因相似个体传播的寄生虫。通过使用一个纳入家族性寄生虫传播的模型，我们表明轻微程度的家族性寄生虫传播足以阻止共同进化的波动。我们的结果预测，红皇后动态及其进化后果的证据最有可能在宿主和寄生虫主要随机混合的生物系统中被发现，而在具有家族聚集的系统中则不太可能被发现。这对红皇后假说以及其他依赖共同进化循环的假说提出了挑战。
