The Early Cretaceous (145–100 million years ago (Ma)) witnessed the rise of flowering plants (angiosperms), which ultimately lead to profound changes in terrestrial plant communities. However, palaeobotanical evidence shows that the transition to widespread angiosperm-dominated biomes was delayed until the Palaeocene (66–56 Ma). Important aspects of the timing and geographical setting of angiosperm diversification during this period, and the groups involved, remain uncertain. Here we address these aspects by constructing and dating a new and complete family-level phylogeny, which we integrate with 16 million geographic occurrence records for angiosperms on a global scale. We show substantial time lags (mean, 37–56 Myr) between the origin of families (stem age) and the diversification leading to extant species (crown ages) across the entire angiosperm tree of life. In turn, our results show that families with the shortest lags are overrepresented in temperate and arid biomes compared with tropical biomes. Our results imply that the diversification and ecological expansion of extant angiosperms was geographically heterogeneous and occurred long after most of their phylogenetic diversity originated during the Cretaceous Terrestrial Revolution.

早白垩世（145-1亿年前（Ma））见证了开花植物（被子植物）的兴起，最终导致陆生植物群落发生深刻变化。然而，古植物学证据表明，向广泛的被子植物为主的生物群落的过渡被推迟到古新世（66-56 Ma）。这一时期被子植物多样化的时间和地理环境的重要方面，以及所涉及的群体，仍然不确定。在这里，我们通过构建和确定一个新的完整的科级系统发育来解决这些方面，我们将其与全球范围内 1600 万个被子植物的地理发生记录相结合。我们表现​​出大量的时间滞后（平均，37-56 Myr）介于科起源（茎龄）和导致整个被子植物生命树现存物种（冠龄）的多样化之间。反过来，我们的结果表明，与热带生物群落相比，在温带和干旱生物群落中滞后时间最短的家庭比例过高。我们的研究结果表明，现存被子植物的多样化和生态扩张在地理上是异质的，并且在它们的大部分系统发育多样性起源于白垩纪陆地革命之后很久就发生了。