FIGS2

Divergence time estimations for subtribe Panicinae. Maximum clade credibility (MCC) tree of Panicoideae obtained from BEAST analyses with ndhF sequences using the uncorrelated lognormal relaxed clock model and secondary calibrations based on external angiosperm fossils together with the phytolith microfossils of Poaceae (calibration scheme 2, see materials and methods). Only subtribe Paniceae is shown in detail; for the remaining clades see Fig. S1. Posterior probabilities ≥ 0.9 are shown on the branches and horizontal bars on the nodes indicate the 95% HPD of ages. Vertical bars indicate sections within Panicum. Paniceae 1 refers to tribe Paniceae excluding subtribes Cenchrinae, Melinidinae, and Panicineae. Mya, million years ago; Pli, Pliocene; Plei, Pleistocene. Results from divergence time estimation based only on external angiosperm fossils calibration are shown in Fig. 2.黍亚族（Panicinae）的分化时间估算。本研究通过BEAST分析，利用ndhF基因序列、无相关对数正态松弛分子钟模型，结合外部被子植物化石与禾本科植硅体微化石作为次级校准（校准方案2，详见材料与方法），获得了黍亚科（Panicoideae）的最大分支可信度（Maximum clade credibility, MCC）树。本图仅详细展示了黍族（Paniceae）分支，其余类群详见补充图S1（Fig. S1）。分支上标注了后验概率≥0.9，节点处的水平条带代表年龄的95%最高后验密度（HPD）区间。垂直条带代表黍属（Panicum）内的组。文中所述的黍族1（Paniceae 1）指排除蒺藜草亚族（Cenchrinae）、马唐草亚族（Melinidinae）及黍亚族（Panicinae）的黍族。Mya即百万年前（million years ago）；Pli为上新世（Pliocene）；Plei为更新世（Pleistocene）。仅基于外部被子植物化石校准的分化时间估算结果见图2（Fig. 2）。