Data from: A global test for phylogenetic signal in shifts in flowering time under climate change

1.Shifts in the timing of flowering are a conspicuous biological signal of climate change. These shifts have been documented across the globe for diverse communities. Although many species are flowering earlier, others have exhibited no shifts or delays in flowering. 2.How species respond phenologically will shape interactions both with other community members and with the abiotic environment, altering fitness, abundance, and ultimately persistence. 3.To understand if variability in phenological response is influenced by evolutionary history, we tested for phylogenetic signal in shifts in flowering onset for thirteen communities representing 116 families across the Northern Hemisphere. We compared the fit of models of neutral evolution (Brownian Motion) with models that incorporate selection (Ornstein-Uhlenbeck). 4.We found significant signal in whether species had shifted and the magnitude of response, with both traits conforming to an Ornstein-Uhlenbeck model of trait evolution. 5.Synthesis. These results show there is global phylogenetic signal in the direction and magnitude of shifts in flowering onset and indicate selection has shaped flowering time responses of related species under climate change; thus, environmentally determined optima may constrain whether and to what degree species respond phenologically to climate change. Our findings further demonstrate the value of testing for phylogenetic signal across multiple communities and comparing multiple models of trait evolution.

1. 开花物候期的时序偏移是气候变化的显著生物学信号。此类变化已在全球范围内的多样植物群落中被观测记录。尽管多数物种的开花时间提前，但仍有部分物种未出现物候变化，或开花期发生延迟。
2. 物种的物候响应模式，将决定其与群落内其他生物类群以及非生物环境的相互作用强度，进而影响物种适合度、种群丰度，最终影响物种的存续能力。
3. 为探明物候响应的差异是否受进化历史调控，我们针对覆盖北半球116个科、共13个研究群落的物种开花始期变化，开展了系统发育信号（phylogenetic signal）检测。我们对比了中性进化模型（布朗运动（Brownian Motion））与纳入选择作用的奥恩斯坦-乌伦贝克模型（Ornstein-Uhlenbeck）的拟合效果。
4. 研究结果显示，物种是否发生开花期偏移以及响应幅度均存在显著的系统发育信号，且两类性状均符合奥恩斯坦-乌伦贝克的性状进化模型。
5. 综合分析表明，开花始期变化的方向与幅度存在全球性的系统发育信号，同时证实选择作用塑造了近缘物种在气候变化背景下的开花物候响应；由此可见，环境决定的进化最适值，可能约束了物种对气候变化产生物候响应的可能性及其程度。本研究进一步证实，在多个群落中开展系统发育信号检测，并比对多种性状进化模型的研究范式具有重要的学术价值。