While functional traits can facilitate or constrain interactions between pair of species in ecological communities, relative abundances regulate the probabilities of encounter among individuals. However, the relative importance of traits and relative abundances for the role species play in seed dispersion networks remains poorly explored. Here, we analyzed 20 Neotropical seed dispersal networks distributed from Mexico to southeastern Brazil to evaluate how relative abundance and functional traits influence bat species' roles in seed dispersal networks. We tested how bat relative abundance and traits relate to species contribution to between-module (c metric) and within-module connectivity (z metric) and their position and potential to mediate indirect effects between species (betweenness centrality). Our results indicate that relative abundance is the main determinant of the role bats play in the networks, while traits such as aspect ratio show modest yet statistically significant importance in predicting specific roles. Moreover, all seed dispersal networks presented two or three superabundant obligatory frugivore species that interacted with a high number of plants. The modest influence of the functional traits on species' roles is likely related to the low variation of morphological traits related to foraging ecology, which reduces the chances of morphological mismatching between consumers and resources in the system. In this scenario, abundant bats have higher chances of encountering resources and being capable of consuming them which leads such species to play critical roles in the community by acting as module hubs and network connectors.

中文翻译：

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蝙蝠在新热带种子传播网络中的作用驱动力：丰度比功能性状更重要。

虽然功能性状可以促进或限制生态社区中一对物种之间的相互作用，但相对丰度调节着个体之间相遇的可能性。然而，对于物种在种子传播网络中所起的作用，性状和相对丰度的相对重要性仍未得到很好的探讨。在这里，我们分析了从墨西哥到巴西东南部分布的20种新热带种子传播网络，以评估相对丰度和功能性状如何影响蝙蝠物种在种子传播网络中的作用。我们测试了蝙蝠的相对丰度和性状与物种对模块间（c度量）和模块内连通性（z度量）的贡献及其在物种之间介导间接影响的地位和潜力（中间性）之间的关系。我们的研究结果表明，相对丰度是蝙蝠在网络中所扮演角色的主要决定因素，而诸如长宽比之类的特征在预测特定角色方面显示出适度但具有统计学意义的重要性。此外，所有种子传播网络都表现出两个或三个与许多植物相互作用的超丰富的强制性节食物种。功能性状对物种作用的适度影响很可能与觅食生态相关的形态性状的低变异有关，这减少了系统中消费者与资源之间形态失配的机会。在这种情况下，