Biogeographic events occurring in the deep past can contribute to the structure of modern ecological communities. However, little is known about how the emergence of envi-ronmental gradients shape the evolution of species that underlie community assembly. In this study, we address how the creation of novel environments lead to community as-sembly via two non-mutually exclusive processes: 1) the immigration and ecological sorting of pre-adapted clades (ISPC), and 2) recent adaptive diversification (RAD). We study these processes in the context of the elevational gradient created by the uplift of the Central Andes. We develop a novel approach and method based on the decomposition of species turnover into within- and among-clade components, where clades correspond to lineages that originated before mountain uplift. Effects of ISPC and RAD can be inferred from how components of turnover change with elevation. We test our approach using data from over 500 Andean forest plots. We found that species turnover between communities at different elevations is dominated by the replacement of clades that originated before the uplift of the Central Andes. Our results suggest that immigration and sorting of clades pre-adapted to montane habitats is the primary mechanism shaping communities across elevations.

中文翻译：

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森林群落在环境梯度上的演化集合：最近的多样化或预先适应的进化枝的分类？

过去发生的生物地理事件可以促进现代生态群落的结构。但是，人们对环境梯度的出现如何影响构成社区聚集基础的物种的进化知之甚少。在这项研究中，我们通过两个互不排斥的过程来探讨新型环境的创建如何导致社区集会：1）预先适应的进化枝（ISPC）的移民和生态分类，以及2）最近的适应性多元化（RAD） ）。我们在安第斯山脉中部隆升造成的海拔梯度的背景下研究了这些过程。我们根据物种周转分解为包层内部和包层之间的成分，开发了一种新颖的方法和方法，其中的枝条对应于山隆起之前起源的谱系。从营业额的组成部分如何随海拔高度变化可以推断出ISPC和RAD的效果。我们使用来自500多个安第斯森林地块的数据测试了我们的方法。我们发现，不同海拔社区之间的物种更新主要由安第斯中部隆升之前产生的进化枝所取代。我们的结果表明，预先适应山地栖息地的进化枝的迁移和分类是影响整个海拔地区群落的主要机制。