Department of Ecology and Evolutionary Biology, Universidade Federal de São Paulo, Campus Diadema, Diadema, SP 04021-001, Brazil.
Graduate Program of Ecology and Evolution, Universidade Federal de São Paulo, Campus Diadema, Diadema, SP 04021-001, Brazil.
J Exp Biol. 2024 Aug 15;227(16). doi: 10.1242/jeb.247497. Epub 2024 Aug 21.
Understanding the intricate relationship between temperature and physiological processes in ectotherm vertebrates is crucial for predicting how these animals respond to environmental changes, including those associated with climate change. This is particularly relevant for the anurans, given their limited capacity for thermoregulation, particularly in larval stages. Herein, we investigated the capacity for thermal acclimatization in Thoropa taophora tadpoles, an endemic species in the Atlantic rainforest of Southeast Brazil, inhabiting distinct thermal environments. These semi-terrestrial tadpoles develop on rocky surfaces, with some populations inhabiting exposed regions near the marine coast where temperatures may reach up to 30°C in sunny conditions, while other populations occupy forested areas near waterfalls that maintain lower temperatures. We aimed to understand the effects of temperature on locomotor performance and on the activity of metabolic enzymes that support performance in tadpoles sampled in four different populations. Moreover, we measured several aspects of thermoregulation, including the critical thermal maximum (CTmax), the body temperature of activity (Tb), the preferred temperature (Tpref) and the effectiveness of thermoregulation (E). Despite differences in body size, tadpoles from warmer environments consistently demonstrated higher locomotor performance, with minimal or no acclimatization seen in other variables. Correlations between habitat temperature and biological endpoints underscore the significance of maximum locomotor performance in shaping physiological responses. Our results show how temperature can impact tadpole behavior and performance, without changes in many organismal measures of thermal acclimatization, providing insights into potential ecological implications, particularly in the context of climate change.
理解变温动物脊椎动物体内温度与生理过程之间复杂的关系对于预测这些动物如何应对环境变化至关重要，包括与气候变化相关的变化。这对于蛙类来说尤为重要，因为它们的体温调节能力有限，尤其是在幼虫阶段。在这里，我们研究了巴西东南大西洋雨林特有物种托罗帕塔福拉蟾（Thoropa taophora）蝌蚪的热驯化能力，该物种栖息在不同的热环境中。这些半陆地蝌蚪在岩石表面发育，一些种群栖息在靠近海洋的暴露地区，那里的温度在晴天可能高达 30°C，而其他种群则栖息在瀑布附近的森林地区，那里的温度较低。我们旨在了解温度对运动表现和代谢酶活性的影响，这些代谢酶活性支持在四个不同种群中采样的蝌蚪的表现。此外，我们测量了几个热调节方面，包括临界热最大值（CTmax）、活动体温（Tb）、偏好温度（Tpref）和热调节效率（E）。尽管体型存在差异，但来自温暖环境的蝌蚪始终表现出更高的运动表现，而在其他变量中几乎没有或没有适应现象。栖息地温度与生物终点之间的相关性强调了最大运动表现对塑造生理反应的重要性。我们的研究结果表明，温度如何影响蝌蚪的行为和表现，而无需对许多生物体的热适应措施进行改变，这为气候变化背景下的潜在生态影响提供了一些见解。
