Data from: Time constraint effects on phenology and life history synchrony in a damselfly along a latitudinal gradient

In organisms with complex life cycles living in seasonal environments, the synchronisation of phenological events is important from the ecological and evolutionary perspectives. Life history transitions should be synchronised to a greater degree at northern latitudes. We quantified hatching and emergence timing and synchrony in the obligate univoltine damselfly Lestes sponsa along a latitudinal gradient covering its entire north-south range in Europe. In our first experiment, populations from different latitudes were grown in separate climate chambers simulating temperature and photoperiod conditions occurring at their sites of origin. Northern populations expressed early and high synchronous hatching and emergence, central populations intermediate, and southern populations late and low synchronous hatching and emergence. This pattern was expressed at both population and full-sibling family levels, indicating stronger selection for timing and synchronisation in the north compared to the south. In our second experiment, populations from all latitudes were reared in conditions simulating an average temperature and photoperiod over the latitudinal gradient. Interestingly, the pattern of timing and synchronisation was reversed with respect to latitude when compared to the pattern shown in the first experiment, indicating the importance of environmental factors in shaping phenological events. Our results indicate strong selection for timing and synchronisation of life history events at northern latitudes, caused by time constraints. Our results also show that it is important to use as natural conditions as possible in experiments on life history shifts in organisms with complex life cycles in order to achieve a correct understanding of these shifts.对于栖息于季节性环境且拥有复杂生活史的生物而言，物候事件的同步性在生态学与进化学视角下均具有重要意义。生活史转换的同步程度在高纬度地区理应更强。本研究以专性一化性豆娘Lestes sponsa为对象，在覆盖其欧洲南北全分布区的纬度梯度上，量化了其孵化与羽化的时间及同步性。在第一项实验中，我们将不同纬度来源的种群置于独立气候箱中培养，模拟其原生栖息地的温度与光周期条件。结果显示，高纬度种群的孵化与羽化时间更早、同步性更高，中纬度种群的表现处于中间水平，而低纬度种群则孵化与羽化更晚且同步性更低。该模式在种群水平与全同胞家系水平均有体现，表明相较于低纬度地区，高纬度地区对发育时间与同步性的选择压力更强。在第二项实验中，我们将所有纬度来源的种群置于模拟该纬度梯度平均温度与光周期的条件下饲养。有趣的是，此时发育时间与同步性随纬度变化的模式与第一项实验结果完全相反，这表明环境因子在塑造物候事件中具有关键作用。本研究结果证实，时间限制压力使得高纬度地区的生活史事件的发育时间与同步性受到了强烈的选择作用。此外，研究还表明，若要准确理解拥有复杂生活史的生物的生活史转变，在相关实验中尽可能采用自然条件至关重要。