The effect of competition between prey species on the evolution of their vulnerabilities to a shared predator
The effect of competition between prey species on the evolution of their vulnerabilities to a shared predator
复制标题
猎物物种之间的竞争对其对共同捕食者的脆弱性进化的影响
DOI：
--
复制
发表时间：
2002
影响因子：
--
通讯作者：
Xin Chen
中科院分区：
文献类型：
--
作者：
P. Abrams;Xin Chen
在这里，我们使用一些简单的模型来研究猎物之间的竞争对猎物物种之间通过共享捕食者的间接进化相互作用的性质的影响。对第二个猎物物种的同情可能会改变共享捕食者种群的种群规模，从而影响第一个猎物物种的反捕食者（脆弱性）特征的适应性进化。这种捕食驱动的性格转变之前已经在模型中进行了研究，这些模型要么假设猎物物种之间没有基于资源的竞争，要么假设猎物的资源使用完全重叠。这项研究考察了猎物物种竞争但在没有捕食者的情况下能够共存的中间情况。这种情况能够产生在限制情况下观察到的两种最常见的反应之一：反捕食者特征的平行变化或这些特征的发散变化。平行变化的特征是竞争相对较低的情况，以及当竞争系数的不对称性不如两个猎物与捕食者的值的比率的不对称性那么极端时竞争性较高的情况。如果竞争系数足够不对称，则在高度竞争或适度竞争时会发生发散变化。探讨了决定性格转变幅度的因素。讨论了这种对与其他猎物物种的同情的进化反应的潜在例子。
Here, we use some simple models to investigate the impact of between-prey competition on the nature of the indirect evolutionary interaction between prey species via shared predators. Sympatry with a second prey species is likely to alter the population size of the shared predator population(s) and thereby affect the adaptive evolution of anti-predator (vulnerability) traits in the first prey species. Such predation-driven character shift has been investigated previously in models that either assumed no resource-based competition between prey species, or complete overlap in resource use by prey. This study examines the intermediate situation in which prey species compete, but are able to co-exist in the absence of the predator. This scenario is capable of producing either of the two most common responses observed in the limiting cases: parallel change in anti-predator characteristics or divergent change in those characteristics. Parallel change characterizes situations with relatively low competition, and those with high competition when the asymmetry in competition coefficients is less extreme than the asymmetry in the ratio of values of the two prey to the predator. Divergent change occurs with high competition or with moderate competition given sufficient asymmetry in competition coefficients. The factors determining the magnitude of character shifts are explored. Potential examples of such evolutionary responses to sympatry with additional prey species are discussed.