The contribution of rare species to community phylogenetic diversity across a global network of forest plots

Niche differentiation has been proposed as an explanation for rarity in species assemblages. Testing this hypothesis requires quantifying the ecological similarity of species. This similarity can potentially be estimated by using phylogenetic relatedness. In this study, we predicted that if niche differentiation does explain the co-occurrence of rare and common species, then rare species should contribute greatly to the overall community phylogenetic diversity (PD), abundance will have phylogenetic signal and that common and rare species will be phylogenetically dissimilar. We tested these predictions by developing a novel method that integrates species rank abundance distributions with phylogenetic trees and trend analyses to examine the relative contribution of individual species to the overall community PD. We then supplement this approach with analyses of phylogenetic signal in abundances and measures of phylogenetic similarity within and between rare and common species groups. We a...

生态位分化（niche differentiation）已被提出作为解释物种集合中物种稀有性的理论假说。检验该假说需量化物种间的生态相似性，而该相似性可通过系统发育亲缘关系（phylogenetic relatedness）进行估算。本研究提出如下预测：若生态位分化确实能够解释稀有种与常见种的共存格局，则稀有种应对群落整体系统发育多样性（phylogenetic diversity, PD）具有显著贡献，物种丰度应具备系统发育信号（phylogenetic signal），且常见种与稀有种在系统发育上存在显著分化。为验证上述预测，本研究开发了一种全新方法：该方法整合物种秩级丰度分布、系统发育树与趋势分析，以探究单个物种对群落整体系统发育多样性的相对贡献。随后，本研究通过分析丰度的系统发育信号，以及测定稀有种与常见物种组内及组间的系统发育相似性，对该方法进行了补充验证。我们将……