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）时期全球环境变化的规模与范围之显著令人瞩目，但此类变化对生物多样性以及物种分化的演化动态所产生的影响，迄今仍未得到充分认知。为探究这一科学问题，本研究整合了被子植物壳斗目（Fagales）的古生物学与现生生物学数据；该类群为拥有约1370个树种的重要生态支系，且其化石记录极为完备。本研究揭示了壳斗目在属级多样性、物种丰富度以及类群更替速率的积累模式上存在显著差异：属级多样性自晚白垩世（Late Cretaceous）起快速演化，并在始新世（Eocene）或渐新世（Oligocene）达到峰值；极端全球气候变化时期的类群更替速率较高，而气候保持稳定时期则相对较低。整个新生代时期，物种丰富度呈现逐步积累的趋势，且可能在中新世中期（Middle Miocene）之后增速加快。物种分化呈现出向新生境拓展的特征：栎类分支在渐新世的亚热带季节性干旱生境中发生辐射演化，木麻黄科（Casuarinaceae）入驻澳大利亚适火生物群系，桦木属（Betula）则进入新近纪晚期（Neogene）的全北界生境。此类辐射演化事件被新近纪晚期湿润暖温带森林中的区域性灭绝事件所抵消。因此，物种层面的整体分化，与具备适配性生态特征的类群在利用新生境时发生的区域性辐射演化密切相关。