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为关键的生物因子之一，但目前我们对其在集合群落（metacommunity）组装过程中的调控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模型，设置了捕食者种类、本地群落间扩散速率以及本地群落物种定殖历史三类变量，实验探究了两类不同捕食者——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. 无论扩散条件如何，广食性捕食均会降低α多样性并提升β多样性，这一现象大概率源于不同本地群落中捕食作用引发的猎物物种随机灭绝存在差异。而当存在专食性捕食者时，扩散会催生源汇动态，进而导致更高的α多样性与小幅降低的β多样性。
4. 本研究结果揭示了不同捕食者对猎物种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结构构建中作用的必要性。