Data from: A metacalibrated time-tree documents the early rise of flowering plant phylogenetic diversity

The establishment of modern terrestrial life is indissociable from angiosperm evolution. While available molecular clock estimates of angiosperm age range from the Paleozoic to the Late Cretaceous, the fossil record is consistent with angiosperm diversification in the Early Cretaceous. The time-frame of angiosperm evolution is here estimated using a sample representing 87% of families and sequences of five plastid and nuclear markers, implementing penalized likelihood and Bayesian relaxed clocks. A literature-based review of the palaeontological record yielded calibrations for 137 phylogenetic nodes. The angiosperm crown age was bound within a confidence interval calculated with a method that considers the fossil record of the group. An Early Cretaceous crown angiosperm age was estimated with high confidence. Magnoliidae, Monocotyledoneae and Eudicotyledoneae diversified synchronously 135–130 million yr ago (Ma); Pentapetalae is 126–121 Ma; and Rosidae (123–115 Ma) preceded Asteridae (119–110 Ma). Family stem ages are continuously distributed between c. 140 and 20 Ma. This time-frame documents an early phylogenetic proliferation that led to the establishment of major angiosperm lineages, and the origin of over half of extant families, in the Cretaceous. While substantial amounts of angiosperm morphological and functional diversity have deep evolutionary roots, extant species richness was probably acquired later.

现代陆地生命的起源与被子植物（angiosperm）的演化密不可分。尽管目前已有的被子植物起源时间分子钟估算结果覆盖从古生代至晚白垩世，但化石记录显示被子植物的多样化发生于早白垩世。本研究以涵盖87%被子植物科的类群样本以及5个质体（plastid）和细胞核（nuclear）标记序列为基础，采用罚似然法（penalized likelihood）与贝叶斯宽松分子钟法（Bayesian relaxed clocks）估算被子植物演化的时间框架。本研究通过对古生物记录的文献综述，为137个系统发育（phylogenetic）节点确立了分子钟校准点。被子植物冠群（crown group）的起源时间被限定在基于该类群化石记录构建的置信区间内。本研究以极高置信度估算出被子植物冠群起源于早白垩世。木兰类（Magnoliidae）、单子叶植物（Monocotyledoneae）与真双子叶植物（Eudicotyledoneae）于135 Ma至130 Ma同步发生多样化；五瓣花类（Pentapetalae）的分化时间为126 Ma至121 Ma；蔷薇亚纲（Rosidae）的分化早于菊亚纲（Asteridae），二者的分化时间分别为123 Ma至115 Ma、119 Ma至110 Ma。各科的茎群（stem group）起源时间大致分布于约1.40亿年至2000万年前。本研究的时间框架证实，白垩纪时期发生了快速的系统发育辐射演化，这一过程促成了被子植物主要演化支的确立，以及现存超半数被子植物科的起源。尽管被子植物的形态与功能多样性具备深厚的演化根源，但现存物种丰富度的积累大概率发生于更晚的时期。