Climate and host plant associations shaped the evolution of ceutorhynch weevils throughout the Cenozoic

Using molecular phylogenetic data and methods we infer divergence times and diversification patterns for the weevil subfamily Ceutorhynchinae in the context of host-plant associations and global climate over evolutionary time. We detected four major diversification shifts that correlate with both host shifts and major climate events. Ceutorhynchinae experienced an increase in diversification rate at ~53 Ma, during the Early Eocene Climate Optimum, coincident with a host shift to Lamiaceae. A second major diversification phase occurred at the end of the Eocene (~34 Ma). This contrasts with the overall deterioration in climate equability at the Eocene-Oligocene boundary, but tracks the diversification of important host plant clades in temperate (higher) latitudes, leading to increased diversification rates in the weevil clades infesting temperate hosts. A third major phase of diversification is correlated with the rising temperatures of the Late Oligocene Warming Event (~26.5 Ma); diversi...本研究借助分子系统发育数据与分析方法，在演化时间尺度上结合寄主植物关联与全球气候背景，对象鼻虫类群中的脊象亚科（Ceutorhynchinae）的分化时间与多样化模式进行推断。本研究共检测到四次主要的多样化转变事件，这些事件均与寄主转移及重大气候事件存在关联。脊象亚科（Ceutorhynchinae）的多样化速率在约53百万年前的始新世气候适宜期（Early Eocene Climate Optimum）出现提升，这一时期恰好对应其寄主转移至唇形科（Lamiaceae）的事件。第二次主要的多样化阶段发生在始新世末期（约34百万年前），该结果与始新世-渐新世边界处全球气候稳定性整体下降的趋势形成反差，但却与温带（高纬度）地区重要寄主植物演化支的多样化进程相契合，进而使得取食温带寄主的象鼻虫演化支的多样化速率得以提升。第三次主要的多样化阶段则与渐新世晚期变暖事件（Late Oligocene Warming Event，约26.5百万年前）的气温回升相关；多样化[原文内容截断]