Data from: Pace of life syndrome under warming and pollution: integrating life history, behavior and physiology across latitudes

To fully comprehend and predict the impact of drivers of global change such as climate warming and pollution, integrated multi-trait approaches are needed. As organismal traits are often correlated, responses to stressors are expected to induce coordinated changes in many traits. A promising framework to study this is the pace-of-life syndrome (POLS), which predicts the integration of life-history, behavioral and physiological traits along a fast-slow continuum. Using an integrative multi-trait approach we evaluated the presence of a POLS both within and across latitudes and how POLS patterns are affected by warming and metal pollution. We studied this in Ischnura elegans damselfly larvae of replicated low-and high latitude populations that strongly differ in voltinism (3-4 generations per year vs. 1 every two years) reared in a common-garden experiment at two temperatures. Across latitudes, life history, behavior and physiology covaried in accordance with the POLS, with the fast-paced low-latitude damselflies characterized by a fast growth rate, high activity and more explorative and risk taking behavior, fast metabolic rate and low investment in immune function (activity of phenoloxidase). This fast POLS strategy was associated with a higher sensitivity to metal exposure and a higher vulnerability to predation. Warming caused opposite responses between the latitudes consistent with differential thermal adaptation in growth rate, behavior and oxidative stress parameters. Despite this, damselflies of both latitudes showed a consistent pattern in phenotypic correlations among traits that, moreover was not affected by warming and metal exposure. Within latitudes there was no full support for the POLS. More active larvae were more explorative and risk taking, which aligned with the fast-slow life-history axis, but less strong than at the across-latitude level. Physiological traits were also integrated within latitudes, yet there was no unambiguous coupling with the fast-slow life-history continuum. The consistent syndrome structure, if underpinned by genetic correlations, may restrict the independent evolution of individual traits, yet may not necessarily constrain adaptive evolution of integrated trait sets. This is because the covariance pattern was to a large extent similar across latitudes and within latitudes, suggesting adaptive trait integration guiding adaptive evolution of trait sets along the fast-slow continuum.

为全面理解并预测气候变暖、污染等全球变化驱动因子的影响，亟需采用整合多性状研究方法。由于生物个体的性状往往存在相关性，因此对胁迫因子的响应会引发多个性状的协同变化。用于开展此类研究的极具前景的框架为生命速率综合征（pace-of-life syndrome, POLS），该理论预测生活史、行为与生理性状会沿“快-慢”连续谱实现整合。本研究采用整合多性状研究方法，评估了纬度内与跨纬度的生命速率综合征（POLS）存在性，以及气候变暖和金属污染对POLS格局的影响。我们以两种温度下的共同花园实验中饲养的、具有重复采样的低纬度与高纬度种群的蓝尾豆娘（Ischnura elegans）幼虫为研究对象，这些种群的年发生代数差异显著（每年3~4代 vs 每2年1代）。跨纬度层面上，生活史、行为与生理性状的协变模式符合POLS理论：快速率的低纬度豆娘表现为生长速率快、活动水平高、探索与冒险行为更强、代谢速率更快，且免疫投入更低（以酚氧化酶活性表征）。这种快速率POLS策略与更高的金属暴露敏感性以及更高的捕食者易感性相关。气候变暖引发了两个纬度种群间的相反响应，这与它们在生长速率、行为与氧化应激参数上的差异化热适应特征相符。尽管存在上述差异，两个纬度的豆娘均表现出一致的性状间表型相关格局，且该格局未受气候变暖和金属暴露的影响。在纬度内层面，并未获得POLS的完全支持。活动水平更高的幼虫探索行为与冒险行为更强，这与快-慢生活史轴相符，但关联强度弱于跨纬度层面。生理性状在纬度内也存在整合，但并未与快-慢生活史连续谱实现明确的耦合。若该一致的综合征结构由遗传相关性所支撑，则可能限制单个性状的独立演化，但未必会约束整合性状集的适应性演化。这是因为协变模式在跨纬度与纬度内层面均大体相似，表明适应性性状整合可指导性状沿快-慢连续谱的适应性演化。