Data from: The rate of seasonal changes in temperature alters acclimation of performance under climate change

How the ability to acclimate will impact individual performance and ecological interactions under climate change remains poorly understood. Theory predicts that the benefit an organism can gain from acclimating depends on the rate at which temperatures change relative to the time it takes to induce beneficial acclimation. Here, we present a conceptual model showing how slower seasonal changes under climate change can alter species’ relative performance when they differ in acclimation rate and magnitude. To test predictions from theory, we performed a microcosm experiment where we reared a mid- and a high-latitude damselfly species alone or together under the rapid seasonality currently experienced at 62°N and the slower seasonality predicted for this latitude under climate change and measured larval growth and survival. To separate acclimation effects from fixed thermal responses, we simulated growth trajectories based on species’ growth rates at constant temperatures and quantified how much, and how fast, species needed to acclimate to match the observed growth trajectories. Consistent with our predictions, the results showed that the mid-latitude species had a greater capacity for acclimation than the high-latitude species. Furthermore, since acclimation occurred at a slower rate than seasonal temperature changes, the mid-latitude species had a small growth advantage over the high-latitude species under the current seasonality, but a greater growth advantage under the slower seasonality predicted for this latitude under climate change. In addition, the two species did not differ in survival under the current seasonality, but the mid-latitude species had higher survival under the predicted climate change scenario, possibly because rates of cannibalism were lower when smaller heterospecifics were present. These findings highlight the need to incorporate acclimation rates in ecological models.

在气候变化背景下，物种的驯化（acclimation）能力如何影响其个体表现与生态互作，目前仍未得到充分阐释。相关理论预测，生物体通过驯化所能获得的收益，取决于温度变化速率与诱导有益驯化所需时长的相对比值。本研究提出一项概念模型，用以阐明：当不同物种的驯化速率与驯化幅度存在差异时，气候变化下更为平缓的季节温度变化将如何改变物种间的相对表现。为验证理论预测，我们开展了一项微宇宙实验（microcosm）：将中纬度与高纬度豆娘物种分别单独饲养，或混合饲养于两种季节温度变化场景中——其一为当前北纬62°地区的快速季节温度变化模式，其二为该纬度在气候变化下预测的平缓季节温度变化模式，并测定了幼虫的生长与存活情况。为将驯化效应与固定热响应效应区分开来，我们基于物种在恒温条件下的生长速率模拟了生长轨迹，并量化了物种需要达到多大的驯化程度、以多快的速率进行驯化，才能匹配观测到的生长轨迹。结果与我们的预测一致：中纬度豆娘物种的驯化能力高于高纬度物种。此外，由于驯化速率慢于季节温度变化速率，在当前季节温度变化模式下，中纬度物种仅具备微弱的生长优势；而在该纬度在气候变化下预测的平缓季节温度变化模式中，中纬度物种的生长优势则更为显著。此外，在当前季节温度变化模式下，两个物种的存活率并无显著差异；但在预测的气候变化场景中，中纬度物种的存活率更高，这可能是因为当存在体型更小的异种个体时，同类相食（cannibalism）的发生率更低。本研究结果凸显了在生态模型中纳入驯化速率参数的必要性。