Modeling the effects of climate-change induced shifts in reproductive phenology on temperature-dependent traits

By altering phenology, organisms have the potential to match life-history events with suitable environmental conditions. Because of this, phenological plasticity has been proposed as a mechanism whereby populations might buffer themselves from climate change. We examine the potential buffering power of advancing one aspect of phenology, nesting date, on sex ratio in painted turtles (Chrysemys picta), a species with temperature-dependent sex determination. We developed a modified constant temperature equivalent model that accounts for the effect of the interaction among climate change, oviposition date, and seasonal thermal pattern on temperature during sexual differentiation and thus on offspring sex ratio. Our results suggest that females will not be able to buffer their progeny from the negative consequences of climate change by adjusting nesting date alone. Not only are offspring sex ratios predicted to become 100% female, but our model suggests that many nests will fail. Because the...生物通过改变物候（phenology），可使其生活史事件与适宜的环境条件相匹配。正因如此，物候可塑性被提出为种群抵御气候变化影响的潜在机制。本研究以具有温度依赖型性别决定（temperature-dependent sex determination）机制的锦龟（Chrysemys picta）为研究对象，探究提前调整其物候的一个维度——筑巢日期——对后代性比的潜在缓冲效应。我们构建了改进的恒温当量模型，该模型可量化气候变化、产卵日期与季节热格局之间的交互作用对性别分化阶段胚胎温度的影响，进而作用于后代性比。研究结果表明，仅通过调整筑巢日期，雌性锦龟无法使后代免受气候变化带来的负面影响。研究不仅预测后代性比将趋近于全雌性，同时模型显示大量筑巢将出现失败情况。由于……