Morphological complexity is a notable feature of multicellular life, although whether it evolves gradually or in early bursts is unclear. Vascular plant reproductive structures, such as flowers, are familiar examples of complex morphology. In this study, we use a simple approach based on the number of part types to analyze changes in complexity over time. We find that reproductive complexity increased in two pulses separated by ~250 million years of stasis, including an initial rise in the Devonian with the radiation of vascular plants and a pronounced increase in the Late Cretaceous that reflects flowering plant diversification. These pulses are associated with innovations that increased functional diversity, suggesting that shifts in complexity are linked to changes in function regardless of whether they occur early or late in the history of vascular plants.

中文翻译：

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生殖创新和植物复杂性的脉冲式上升

形态复杂性是多细胞生命的一个显着特征，尽管它是逐渐进化还是早期爆发尚不清楚。维管植物的生殖结构，如花，是复杂形态的常见例子。在这项研究中，我们使用一种基于零件类型数量的简单方法来分析复杂性随时间的变化。我们发现生殖复杂性在相隔约 2.5 亿年停滞的两个脉冲中增加，包括随着维管植物的辐射在泥盆纪的初始上升和反映开花植物多样化的晚白垩纪的显着增加。这些脉冲与增加功能多样性的创新有关，