Department of Zoology, Stockholm University, Sweden.
Am Nat. 2012 Oct;180(4):464-80. doi: 10.1086/667594. Epub 2012 Aug 21.
Although understanding female reproduction is crucial for population demography, determining how and to what relative extent it is constrained by different ecological factors is complicated by difficulties in studying the links between individual behavior, life history, and fitness in nature. We present data on females in a natural population of the butterfly Leptidea sinapis. These data were combined with climate records and laboratory estimates of life-history parameters to predict the relative impact of different ecological constraints on female fitness in the wild. Using simulation models, we partitioned effects of male courtship, host plant availability, and temperature on female fitness. Results of these models indicate that temperature is the most constraining factor on female fitness, followed by host plant availability; the short-term negative effects of male courtship that were detected in the field study were less important in models predicting female reproductive success over the entire life span. In the simulations, females with more reproductive reserves were more limited by the ecological variables. Reproductive physiology and egg-laying behavior were therefore predicted to be co-optimized but reach different optima for females of different body sizes; this prediction is supported by the empirical data. This study thus highlights the need for studying behavioral and life-history variation in orchestration to achieve a more complete picture of both demographic and evolutionary processes in naturally variable and unpredictable environments.
尽管了解女性生殖对于人口统计学至关重要，但由于在自然环境中研究个体行为、生活史和适应度之间的联系存在困难，因此确定不同生态因素如何以及在多大程度上对其产生限制变得复杂。我们提供了关于蝴蝶 Leptidea sinapis 自然种群中雌性的数据。这些数据与气候记录和实验室估计的生活史参数相结合，用于预测不同生态限制因素对野生雌性适应度的相对影响。我们使用模拟模型，将雄性求偶、寄主植物可用性和温度对雌性适应度的影响进行了划分。这些模型的结果表明，温度是对雌性适应度最具限制作用的因素，其次是寄主植物的可用性；在野外研究中检测到的雄性求偶的短期负面影响在预测雌性整个生命周期生殖成功率的模型中并不重要。在模拟中，具有更多生殖储备的雌性受到生态变量的限制更大。因此，预测生殖生理学和产卵行为是共同优化的，但对于不同体型的雌性，它们会达到不同的最优状态；这一预测得到了经验数据的支持。因此，这项研究强调了需要研究行为和生活史变化的协调，以在自然变化和不可预测的环境中更全面地了解人口统计学和进化过程。
