Data from: The effects of archipelago spatial structure on island diversity and endemism: predictions from a spatially-structured neutral model

Islands are particularly suited to testing hypotheses about the ecological and evolutionary mechanisms underpinning community assembly. Yet the complex spatial arrangements of real island systems have received little attention from both empirical studies and theoretical models. Here, we investigate the extent to which the spatial structure of archipelagos affects species diversity and endemism. We start by proposing a new spatially-structured neutral model that explicitly considers archipelago structure, and then investigate its predictions under a diversity of scenarios. Our results suggest that considering the spatial structure of archipelagos is crucial to understanding their diversity and endemism, with structured island systems acting both as “museums” and “cradles” of biodiversity. These dynamics of diversification may change the traditionally expected pattern of decrease in species richness with distance from the mainland, even potentially leading to increasing patterns for taxa with high speciation rates in archipelagos off species-poor continental areas. Our results also predict that, within spatially-structured archipelagos, metapopulation dynamics and evolutionary processes can generate higher diversity on islands more centrally placed than at the periphery. We derive from our results a set of theoretical predictions, potentially testable with empirical data.岛屿尤其适合用于检验支撑群落构建（community assembly）的生态与进化机制相关假说。然而，现实岛屿系统的复杂空间格局，无论在实证研究还是理论模型领域，均未得到足够的关注。本研究旨在探究群岛（archipelago）的空间结构对物种多样性（species diversity）与特有性（endemism）的影响程度。首先，我们提出一种全新的空间结构化中性模型（spatially-structured neutral model），该模型可明确考量群岛结构；随后，我们在多种情景下对该模型的预测结果展开系统性探究。研究结果显示，厘清群岛的空间结构，对于理解其物种多样性与特有性至关重要——结构化岛屿系统兼具生物多样性的“博物馆”与“摇篮”双重属性。这类多样化的演化动态，或将颠覆学界传统认知中“物种丰富度随与大陆的距离增加而降低”的经典模式；在物种贫乏大陆周边海域的群岛中，甚至可能对具有高成种率（speciation rate）的类群呈现出物种丰富度上升的趋势。本研究同时预测，在空间结构化的群岛中，集合种群动态（metapopulation dynamics）与进化过程将使得位于中心区域的岛屿，比边缘岛屿拥有更高的物种多样性。基于上述研究结果，我们推导出一系列理论预测，这些预测均可通过实证数据开展检验。