Species interact in different ways, including competition, facilitation and predation. These interactions can be non‐linear or higher order and may depend on time or species densities. Although these higher‐order interactions are virtually ubiquitous, they remain poorly understood, as they are challenging both theoretically and empirically. We propose to adapt niche and fitness differences from modern coexistence theory and apply them to species interactions over time. As such, they may not merely inform about coexistence, but provide a deeper understanding of how species interactions change. Here, we investigated how the exploitation of a biotic resource (plant) by phytophagous arthropods affects their interactions. We performed monoculture and competition experiments to fit a generalized additive mixed model to the empirical data, which allowed us to calculate niche and fitness differences. We found that species switch between different types of interactions over time, including intra‐ and interspecific facilitation, and strong and weak competition.

中文翻译：

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高阶物种相互作用导致时间依赖性生态位和适应度差异：植物饲养节肢动物的实验证据

物种以不同的方式相互作用，包括竞争、促进和捕食。这些相互作用可以是非线性的或更高阶的，并且可能取决于时间或物种密度。尽管这些高阶相互作用实际上无处不在，但人们对它们仍然知之甚少，因为它们在理论和经验上都具有挑战性。我们建议适应现代共存理论中的生态位和适应度差异，并将其应用于随着时间的推移的物种相互作用。因此，它们不仅可以告知共存，还可以更深入地了解物种相互作用如何变化。在这里，我们研究了植食性节肢动物对生物资源（植物）的利用如何影响它们的相互作用。我们进行了单一栽培和竞争实验，以将广义加性混合模型与经验数据相拟合，这使我们能够计算生态位和适应度差异。我们发现，随着时间的推移，物种会在不同类型的相互作用之间切换，包括种内和种间促进，以及强竞争和弱竞争。