Data from: The geography of morphological convergence in the radiations of Pacific Sebastes rockfishes

The evolution of convergent phenotypes in lineages subject to similar selective pressures is a common feature of adaptive radiation. In geographically replicated radiations, repeated convergence occurs between clades occupying distinct regions or islands. Alternatively, a clade may repeatedly reach the same adaptive peaks in broad-scale sympatry, resulting in extensive convergence within a region. Rockfish (Sebastes sp.) have radiated in both the northeast and northwest Pacific, allowing tests of the extent and geographic pattern of convergence in a marine environment. We use a suite of phylogenetically-informed methods to test for morphological convergence in rockfish. We examined patterns of faunal similarity using nearest neighbor distances in morphospace and the frequency of morphologically similar yet distantly related species pairs. The extent of convergence both between regions and within the northeast Pacific exceeds the expectation under a Brownian motion null model, although constraints on trait space could account for the similarity. We then use a recently developed method (SURFACE) to identify adaptive peak shifts in Sebastes' evolutionary history. We found that the majority of convergent peak shifts occur within the northeast Pacific rather than between regions, and that the signal of peak shifts is strongest for traits related to trophic morphology. Pacific rockfish thus demonstrate a tendency toward morphological convergence within one of the two broad geographic regions in which they have diversified.

趋同表型（convergent phenotypes）在受相似选择压力作用的演化支中的演化，是适应辐射（adaptive radiation）的常见特征。在地理重复的辐射演化事件中，占据不同区域或岛屿的演化支（clades）之间会反复出现趋同现象。此外，某一演化支也可能在大范围同域分布（sympatry）的背景下，反复抵达相同的适应峰，进而在单一区域内引发广泛的趋同演化。
岩鱼属（Sebastes sp.）在东北太平洋与西北太平洋均发生了辐射演化，这为我们在海洋环境中检验趋同演化的程度与地理模式提供了理想的研究体系。我们采用一系列基于系统发育信息的分析方法，对岩鱼属的形态趋同现象开展检验。我们通过形态空间（morphospace）中的最近邻距离（nearest neighbor distances）以及形态相似但亲缘关系较远的物种对的出现频率，分析类群相似性（faunal similarity）模式。
无论是区域间还是东北太平洋内部的趋同演化程度，均超出了布朗运动零模型（Brownian motion null model）下的预期值，尽管性状空间的约束效应或许可以解释这种相似性。随后我们借助新近开发的SURFACE方法，识别岩鱼属演化历史中的适应峰位移（adaptive peak shifts）。我们发现，绝大多数趋同峰位移均发生在东北太平洋内部，而非不同区域之间；且峰位移信号在营养形态学（trophic morphology）相关性状中表现最为显著。
综上，太平洋岩鱼属在其分化的两大地理区域之一内部，展现出了显著的形态趋同演化倾向。