Data from: Fossils and a large molecular phylogeny show that the evolution of species richness, generic diversity and turn-over rates are disconnected

The magnitude and extent of global change during the Cenozoic are remarkable, yet the impacts of these changes on biodiversity and the evolutionary dynamics of species diversification remain poorly understood. To investigate this question we combine palaeontological and neontological data for the angiosperm order Fagales, an ecologically important clade of c. 1370 species of trees with an exceptional fossil record. We show differences in patterns of accumulation of generic diversity, species richness, and turnover rates for Fagales. Generic diversity evolved rapidly from the Late Cretaceous and peaked in the Eocene or Oligocene. Turnover rates were high during periods of extreme global climate change, but relatively low when the climate remained stable. Species richness accumulated gradually throughout the Cenozoic, possibly at an accelerated pace after the Middle Miocene. Species diversification was into new environments: Quercoids radiating in Oligocene subtropical seasonally arid habitats, Casuarinaceae in Australian pyrophytic biomes, and Betula into late Neogene holarctic habitats. These radiations were counterbalanced by regional extinctions in late-Neogene mesic warm-temperate forests. Thus overall diversification at species level is linked to regional radiations of clades with appropriate ecologies exploiting newly available habitats.新生代（Cenozoic）时期全球变化的规模与程度堪称显著，但此类变化对生物多样性及物种分化演化动态的影响仍有待深入阐释。为探究这一科学问题，本研究整合了被子植物（angiosperm）类群中壳斗目（Fagales）的古生物学的（palaeontological）与现生生物学的（neontological）数据：该类群为生态重要的演化支（clade），包含约1370种树木，且拥有极为完整的化石记录。研究揭示了壳斗目的属多样性（generic diversity）累积模式、物种丰富度（species richness）及更替速率（turnover rates）存在显著差异：属多样性自晚白垩世（Late Cretaceous）起快速演化，并在始新世（Eocene）或渐新世（Oligocene）达到峰值；在极端全球气候变化时期，类群更替速率较高，而气候稳定阶段则相对较低。物种丰富度在整个新生代时期呈逐步累积态势，或在中新世中期（Middle Miocene）后加速提升。物种分化朝向新生境拓展：栎类群（Quercoids）于渐新世在亚热带季节性干旱生境中发生辐射演化，木麻黄科（Casuarinaceae）在澳大利亚火适应型生物群系（pyrophytic biomes）中扩张，桦木属（Betula）则侵入晚新近纪（late Neogene）的全北界生境（holarctic habitats）。此类辐射演化被晚新近纪湿润暖温带森林中的区域灭绝事件所抵消。综上，物种层面的整体分化，与具备适配生态的演化支利用新生境所发生的区域辐射演化密切相关。