Data from: Diet complementation as a frequency‐dependent mechanism conferring advantages to rare plants via dispersal

1. We used an agent-based model to test the hypothesis that diet complementation by frugivores can promote the persistence of rare plant species in communities (DCH). 2. Models simulated bird movement, frugivory, seed-dispersal, and plant recruitment on landscapes that differed in their degree of fragmentation and in their degree of fruiting species mixing at the scale of frugivores’ foraging decisions. 3. Diet complementation promoted the dispersal of rare-species without the need of a priori preference from birds. The effects of landscape structure on the dispersal of rare plants were small (<5%) compared to positive effects of diet complementation because birds tracked the nutrients contained in rare fruits to balance their diets. However, resource-tracking of rare fruits increased foraging costs up to 20% of net energy intakes. 4. During post-dispersal stages, density-dependent mortality only conferred advantages to rare plants when located within hetero-specific plant patches. Still, thanks to rare-biased dispersal, rare plants showed the highest seed dispersal effectiveness irrespectively of landscape configuration. 5. Our theoretical approach presents a behavioral mechanism by which fruit choice can act as a frequency-dependent mechanism conferring rare-species advantages as important as classic post-dispersal density-dependent processes. 6. We hope that this study stimulates future work aimed at evaluating the importance of diet complementation in structuring the composition and spatial patterning of plant communities.

1. 本研究采用基于智能体模型（agent-based model），检验了食果动物（frugivore）的饮食互补效应可促进群落中稀有植物物种存续的假说（DCH）。
2. 模型模拟了鸟类活动、食果行为、种子扩散与植物更新过程，实验景观设置了两类差异变量：景观破碎化程度，以及食果动物觅食决策尺度下的结实物种混交程度。
3. 饮食互补效应可在无需鸟类产生先天偏好的前提下，促进稀有物种的种子扩散。相较于饮食互补的正向效应，景观结构对稀有植物种子扩散的影响微弱（不足5%），这是因为鸟类会通过取食稀有果实获取所需营养以平衡自身饮食。不过，对稀有果实的资源追踪行为会使觅食成本上升，最高可达净能量摄入的20%。
4. 在扩散后阶段，密度制约死亡率仅当稀有植物处于异种植物斑块中时，才能为其带来生存优势。但得益于偏向稀有物种的扩散模式，无论景观配置如何，稀有植物均展现出最高的种子扩散有效性。
5. 本理论研究提出了一种行为学机制：果实选择可作为一种频率依赖机制，为稀有物种带来与经典扩散后密度制约过程同等重要的生存优势。
6. 本研究希望能够推动后续相关研究，以评估饮食互补效应在塑造植物群落组成与空间格局中的重要性。