A multilocus phylogenetic analysis of Escallonia (Escalloniaceae): diversification in montane South America

The mountains of South America are hotspots of plant diversity. How this diversity originated and evolved, and what roles geographic and environmental factors may have played in the diversification of lineages occurring in these regions is not well understood. Escallonia, a morphologically and ecologically diverse group of shrubs and trees widely distributed in these mountains, provides an ideal opportunity for studying the historical underpinnings that have shaped the extraordinarily distinctive, diverse, and endangered flora of these regions, and for evaluating the role of abiotic factors in the process of lineage divergence. I analyzed neutral DNA sequence data from two nuclear loci and one chloroplast locus using maximum parsimony, maximum likelihood, and Bayesian phylogenetic approaches. I used a Bayesian approach to analyze the geographic structure of gene trees, and a phylogenetically controlled decomposition of the variance in bioclimatic variables to analyze the eco-climatic st...

南美洲山地是植物多样性的热点区域。目前学界对该区域植物多样性的起源与演化历程，以及地理与环境因子在当地类群分化过程中发挥的作用尚未形成充分认知。南鼠刺属（Escallonia）是一类形态与生态特征均具有丰富多样性的灌木与乔木类群，广泛分布于上述山地，为研究塑造该区域极具特色、多样且濒危的植物区系的历史成因，以及评估非生物因子在类群分化过程中的作用提供了理想的研究契机。本研究采用最大简约法、最大似然法以及贝叶斯系统发育分析方法，对2个核基因座与1个叶绿体基因座的中性DNA序列数据开展分析；同时利用贝叶斯方法解析基因树的地理结构，并通过系统发育校正的生物气候变量方差分解，探究生态气候特征...