Large-scale longitudinal gradients of genetic diversity: a meta-analysis across six phyla in the Mediterranean basins

Predicting patterns of variation in biodiversity across the globe is a fundamental issue in ecology and evolution. Diversity within species, that is, genetic diversity, is of prime importance for understanding past and present evolutionary patterns, and highlighting areas where conservation might be a priority. However, most studies on spatial patterns of genetic diversity have not considered longitude as a potentially important ecological driver of these patterns. Therefore, we carried out a meta-analysis to examine the longitudinal patterns of genetic diversity in the Mediterranean Basin. Using published literature and a systematic review/meta-analysis framework, we collected data on the genetic diversity of species whose populations occur in the Mediterranean basin. We then calculated a coefficient of correlation between within‐population genetic diversity indices and longitude, and estimated the role of biological, ecological, biogeographic, and marker type factors on the strength and magnitude of this correlation in six phylla. The results of this study were published in the paper titled Large‐scale longitudinal gradients of genetic diversity: a meta‐analysis across six phyla in the Mediterranean basin (Conord et al. 2012).预测全球生物多样性的变异格局是生态学与进化生物学领域的核心议题之一。物种内的多样性，即遗传多样性（genetic diversity），对于解析过往与当前的进化格局、识别保护优先级区域均具有至关重要的意义。然而，现有绝大多数针对遗传多样性空间格局的研究，均未将经度视为驱动此类格局的潜在关键生态因子。有鉴于此，本研究开展了一项荟萃分析（meta-analysis），以探究地中海盆地（Mediterranean Basin）内遗传多样性的经度梯度格局。本研究依托已发表文献与系统综述/荟萃分析框架，收集了种群分布于地中海盆地的物种的遗传多样性数据。随后，我们计算了种群内遗传多样性指数与经度之间的相关系数，并针对六大生物门（phyla），评估了生物学、生态学、生物地理学以及标记类型等因素对该相关系数的强度与效应幅度的调控作用。本研究成果已发表于题为《遗传多样性的大尺度经度梯度：地中海盆地六大生物门的荟萃分析》（Large‐scale longitudinal gradients of genetic diversity: a meta‐analysis across six phyla in the Mediterranean basin）的论文中（Conord et al. 2012）。