Data from: An adaptive radiation of frogs in a Southeast Asian island archipelago

Living amphibians exhibit a diversity of ecologies, life histories, and species-rich lineages that offers opportunities for studies of adaptive radiation. We characterize a diverse clade of frogs (Kaloula, Microhylidae) in the Philippine island archipelago as an example of an adaptive radiation into three primary habitat specialists or ecotypes. We use a novel phylogenetic estimate for this clade to evaluate the tempo of lineage accumulation and morphological diversification. Because species-level phylogenetic estimates for Philippine Kaloula are lacking, we employ dense population sampling to determine the appropriate evolutionary lineages for diversification analyses. We explicitly take phylogenetic uncertainty into account when calculating diversification and disparification statistics and fitting models of diversification. Following dispersal to the Philippines from Southeast Asia, Kaloula radiated rapidly into several well-supported clades. Morphological variation within Kaloula is partly explained by ecotype and accumulated at high levels during this radiation, including within ecotypes. We pinpoint an axis of morphospace related directly to climbing and digging behaviors and find patterns of phenotypic evolution suggestive of ecological opportunity with partitioning into distinct habitat specialists. We conclude by discussing the components of phenotypic diversity that are likely important in amphibian adaptive radiations.现存两栖动物类群拥有多样的生态类型、生活史策略与物种丰富的演化支系，为适应辐射（adaptive radiation）研究提供了绝佳契机。我们以菲律宾群岛分布的多样性蛙类支系——狭口蛙科（Microhylidae）的Kaloula属（Kaloula）——为实例，对其展开表征分析：该类群通过适应辐射分化为三类核心的生境特化类群（或称生态型，ecotypes）。我们针对该支系构建了全新的系统发育估算（phylogenetic estimate），以此分析支系积累与形态分化（morphological diversification）的演化速率。由于此前缺乏针对菲律宾地区Kaloula属的物种级系统发育估算，我们通过高密度种群采样，明确了适用于分化分析的演化支系划分方案。在计算分化与性状分化（disparification）统计量以及拟合分化模型时，我们充分考虑了系统发育不确定性（phylogenetic uncertainty）的影响。自东南亚扩散至菲律宾群岛后，Kaloula属迅速发生适应辐射，分化为多个高支持度的演化支系。Kaloula属内的形态变异可部分归因于生态型分化，且在该辐射过程中（包括各生态型内部）积累了较高水平的形态差异。我们精准定位到与攀爬、掘穴行为直接相关的形态空间（morphospace）轴，并发现表型演化（phenotypic evolution）模式暗示了生态机遇的存在——该类群通过分化为不同的生境特化类群完成了生态位分区。最后，我们讨论了两栖动物适应辐射中可能发挥关键作用的表型多样性组成要素。