Niche and neutral processes jointly influence species interactions. Predictions of interactions based on these processes assume that they operate similarly across all species. However, species characteristics could systematically create differences in the strength of niche or neutral processes for each interspecific interaction. We used national-level records of plant-frugivore interactions, species traits, biogeographic status (native vs. exotic), phylogenies and species range sizes to test the hypothesis that the strength of niche processes in species interactions changes in predictable ways depending on trophic generalism and biogeographic status of the interacting species. The strength of niche processes (measured as trait matching) decreased when the generalism of the interacting partners increased. Furthermore, the slope of this negative relationship between trait matching and generalism of the interacting partners was steeper (more negative) for interactions between exotic species than those between native species. These results remained significant after accounting for the potential effects of neutral processes (estimated by species range size). These observed changes in the strength of niche processes in generating species interactions, after accounting for effects of neutral processes, could improve predictions of ecological networks from species trait data. Specifically, due to their shorter coevolutionary history, exotic species tend to interact with native species even when lower trait matching occurs than in interactions among native species. Likewise, interactions between generalist bird species and generalist plant species should be expected to occur despite low trait matching between species, whereas interactions between specialist species involve higher trait matching.

中文翻译：

---

对于通才和外来物种，物种相互作用的生态位过程的强度较低

生态位和中性过程共同影响物种相互作用。基于这些过程的相互作用预测假设它们在所有物种中的运作方式相似。然而，物种特征可以系统地产生每个种间相互作用的生态位或中性过程的强度差异。我们使用植物 - 食果动物相互作用、物种特征、生物地理状态（本地与外来）、系统发育和物种范围大小的国家级记录来检验物种相互作用中生态位过程的强度以可预测的方式变化的假设，这取决于营养泛滥和相互作用物种的生物地理状况。当互动伙伴的普遍性增加时，利基过程的强度（以特征匹配来衡量）会降低。此外，外来物种之间的相互作用比本地物种之间的相互作用更陡峭（更消极）。在考虑了中性过程的潜在影响（按物种范围大小估计）后，这些结果仍然显着。在考虑了中性过程的影响后，这些观察到的生态位过程在产生物种相互作用方面的强度变化可以提高物种特征数据对生态网络的预测。具体而言，由于它们的共同进化历史较短，外来物种倾向于与本地物种相互作用，即使发生的性状匹配低于本地物种之间的相互作用。同样地，