Data from: Predator identity influences metacommunity assembly

1.Predation is among the most important biotic factors influencing natural communities, yet we have a rather rudimentary understanding of its role in modulating metacommunity assembly. 2.We experimentally examined the effects of two different predators (a generalist and a specialist) on metacommunity assembly, using protist microcosm metacommunities that varied in predator identity, dispersal among local communities, and the history of species colonization into local communities. 3.Generalist predation resulted in reduced α diversity and increased β diversity irrespective of dispersal, likely due to predation-induced stochastic extinction of different prey species in different local communities. Dispersal, however, induced source-sink dynamics in the presence of specialist predators, resulting in higher α diversity and marginally lower β diversity. 4.These results demonstrate the distinct effects of different predators on prey metacommunity assembly, emphasizing the need to explore the role of predator diet breadth in structuring metacommunities.1. 捕食作用是影响自然群落的最重要生物因子之一，但目前我们对其在调控集合群落（metacommunity）组装过程中的作用仍仅有粗浅认知。 2. 本研究以原生动物微宇宙集合群落为实验体系，设置不同捕食者种类、局域群落间扩散强度以及局域群落物种定殖历史三个变量，实验探究了两类捕食者（广食性捕食者与专食性捕食者）对集合群落组装过程的影响。 3. 无论扩散强度如何，广食性捕食作用均会降低α多样性（α diversity）并提升β多样性（β diversity），这可能是因为捕食作用引发不同局域群落内不同猎物物种发生随机灭绝所致。而在专食性捕食者存在的条件下，扩散会诱导源汇动态（source-sink dynamics）的形成，最终使得α多样性升高、β多样性小幅降低。 4. 本研究结果揭示了不同捕食者对猎物集合群落组装过程的差异化影响，强调了探究捕食者食性宽度在集合群落构建过程中作用的必要性。