Ecologically dominant species can shape the assembly of ecological communities via altering competitive outcomes. Moreover, these effects may be amplified under limited niche differentiation. Nevertheless, the influences of ecological dominance and niche differentiation on assembly are rarely considered together. Here, we provide a novel examination of dominance in a diverse arboreal ant community, defining dominance by the prevalent usage of nesting resources and addressing how it influences community assembly. We first used a series of quantitative observational and experimental studies to address the natural nesting ecology, colony incidence on surveyed trees, and level of dominance over newly available nesting resources by our focal species, Cephalotes pusillus. The experimental studies were then used further to examine whether C. pusillus shapes assembly via an influence on cavity usage by co-occurring species. C. pusillus was confirmed as a dominant user of cavity nesting resources, with highly generalized nesting ecology, occupying about 50% of the trees within the focal system, and accounting for more than a third of new cavity occupation in experiments. Our experiments showed further that the presence of C. pusillus was associated with modest effects on species richness, but significant decreases in cavity-occupation levels and significant shifts in the entrance-size usage by co-occurring species. These results indicate that C. pusillus, as a dominant user of nesting resources, shapes assembly at multiple levels. Broadly, our findings highlight that complex interactions between a dominant species and the resource-usage patterns of other species can underlie species assembly in diverse ecological communities.

具有生态优势的物种可以通过改变竞争结果来塑造生态群落的集合。而且，这些作用可能会在有限的生态位分化下被放大。然而，很少将生态优势和生态位分化对装配的影响综合考虑。在这里，我们提供了一个新颖的考试，探讨了多样化的树状蚂蚁社区中的优势地位，并通过广泛使用嵌套资源来定义优势地位，并探讨了它如何影响社区聚集。我们首先使用了一系列定量观察和实验研究，以解决自然筑巢生态，被调查树木的集落发生率以及我们的重点物种头孢霉在新近可用的筑巢资源上的优势水平。。然后将实验研究进一步用于检查C是否。脓毒症通过同时存在的物种对空洞使用的影响来影响组装。证实脓毒梭菌是腔巢资源的主要使用者，具有高度笼统的筑巢生态，占据了焦点系统内约50％的树木，并占实验中新腔占据的三分之一以上。我们的实验进一步表明，脓毒梭菌的存在与对物种丰富度的适度影响有关，但共生物种的空腔占有水平显着降低，入口大小使用显着变化。这些结果表明脓杆菌，作为嵌套资源的主要用户，可以在多个层次上对组装进行调整。从广义上讲，我们的研究结果表明，优势物种与其他物种的资源利用模式之间的复杂相互作用可以成为各种生态群落中物种聚集的基础。