Laboratorio de Ecología, Biología Evolutiva y Comportamiento de Herpetozoos, Instituto de Investigaciones en Biodiversidad y Medioambiente (INIBIOMA), CONICET-UNCOMA, Quintral 1250 (8400), Bariloche, Río Negro, Argentina.
Laboratorio de Ecología, Biología Evolutiva y Comportamiento de Herpetozoos, Instituto de Investigaciones en Biodiversidad y Medioambiente (INIBIOMA), CONICET-UNCOMA, Quintral 1250 (8400), Bariloche, Río Negro, Argentina.
J Therm Biol. 2020 Dec;94:102744. doi: 10.1016/j.jtherbio.2020.102744. Epub 2020 Sep 25.
Most of the literature on temperature-organism interactions rely on mean temperature (mostly air), disregarding the real complexity of this variable. There is a growing consensus about the importance of considering the temperature fluctuations as a mechanism improving organism's performance. Tadpoles are small body size ectotherm organisms that behave isothermally with their environment. As such, are good models for studying their thermal biology relative to their immediate environment. We studied six anuran tadpole species in North Patagonia, Alsodes gargola, Hylorina sylvatica, Batrachyla taeniata, Pleurodema thaul, P. bufoninum and Rhinella spinulosa, distributed in a West-East altitudinal cline with different environments and thermal conditions. We evaluated the relationship between thermal descriptors at a local scale and the thermal biology patterns of these temperate tadpoles. We estimated thermal tolerance limits and thermal sensitivity of locomotion of each species. The different aquatic environments showed important differences in local thermal conditions, associated with observed differences in the thermal traits in these tadpoles. Species exposed to lower temperature fluctuations and lower environmental mean temperatures showed lower swimming optimal temperatures and narrower thermal tolerance ranges. We found greater variability in the upper than in the lower critical limits in these Patagonian anuran tadpoles. Minimum critical temperatures were close to freezing temperature, possibly in detriment of their tolerance to high temperatures. Overall, our results suggest that these species are adapted to low temperatures. Finally, warming tolerances and predicted thermal safety margins, show that none of the studied species appear to be under thermal stress that may compromise their survival at the present time or in the near future, under a moderate climate change scenario.
大多数关于温度与生物相互作用的文献都依赖于平均温度（主要是空气），而忽略了这个变量的实际复杂性。越来越多的人认为，考虑温度波动作为一种提高生物表现的机制是很重要的。蝌蚪是小型的外温动物，与环境等温。因此，它们是研究与其直接环境相关的热生物学的良好模型。我们研究了北巴塔哥尼亚的六种有尾目蝌蚪物种，即 Gargola、Hylorina sylvatica、Batrachyla taeniata、Pleurodema thaul、P. bufoninum 和 Rhinella spinulosa，它们分布在一个具有不同环境和热条件的西向东海拔梯度上。我们评估了局部尺度上的热描述符与这些温带蝌蚪的热生物学模式之间的关系。我们估计了每个物种的热耐受极限和运动的热敏感性。不同的水生环境表现出重要的局部热条件差异，这与这些蝌蚪中观察到的热特征差异有关。暴露在较低温度波动和较低环境平均温度下的物种表现出较低的游泳最佳温度和较窄的热耐受范围。我们发现这些巴塔哥尼亚有尾目蝌蚪的上临界极限比下临界极限具有更大的可变性。最小临界温度接近冰点，可能不利于它们对高温的耐受。总的来说，我们的结果表明，这些物种适应低温。最后，耐温性和预测的热安全裕度表明，在所研究的物种中，没有一种物种似乎受到可能危及它们目前或不久的将来生存的热压力的影响，在温和的气候变化情景下。
