Facultative hyperthermia during a heatwave delays injurious dehydration of an arboreal marsupial
Facultative hyperthermia during a heatwave delays injurious dehydration of an arboreal marsupial
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热浪期间的兼性高温可延迟树栖有袋动物的损伤性脱水
DOI：
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发表时间：
2020
影响因子：
2.8
通讯作者：
James M. Turner
中科院分区：
文献类型：
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作者：
James M. Turner
热浪对野生动物种群产生负面影响，随着全球变暖的持续，其影响预计会加剧。动物在极高环境温度（Ta）下的大量死亡是生理功能障碍的证据，为了帮助保护工作，提高我们对动物对环境热反应的理解至关重要。为了解决这个问题，我在模拟的热浪中测量了一只澳大利亚有袋动物的失水、体温和新陈代谢。在29-39℃的温度下，普通环尾负鼠（Pseudocheirus peregrinus）的体温被动升高约3℃，节水9.6 ml h - 1。当Ta超过35-36°C的阈值时，负鼠开始通过增加蒸发失水和热导率来主动冷却。很明显，兼性热疗在一定程度上是有效的，但一旦超过这个限度——随着气候变化，超过这个限度的频率和持续时间也在增加——体内的水分就会迅速耗尽，使负鼠面临因脱水而受伤或死亡的危险。当外面很热的时候，负鼠可以通过让体温随着热量上升来节约水分，避免危险的脱水程度。
ABSTRACT Heatwaves negatively impact wildlife populations and their effects are predicted to worsen with ongoing global warming. Animal mass mortality at extremely high ambient temperature (Ta) is evidence for physiological dysfunction and, to aid conservation efforts, improving our understanding of animal responses to environmental heat is crucial. To address this, I measured the water loss, body temperature and metabolism of an Australian marsupial during a simulated heatwave. The body temperature of the common ringtail possum Pseudocheirus peregrinus increased passively by ∼3°C over a Ta of 29–39°C, conveying water savings of 9.6 ml h−1. When Ta crossed a threshold of 35–36°C, possums began actively cooling by increasing evaporative water loss and thermal conductance. It is clear that facultative hyperthermia is effective up to a point, but once this point is surpassed – the frequency and duration of which are increasing with climate change – body water would rapidly deplete, placing possums in danger of injury or death from dehydration. Highlighted Article: When it is hot outside, a possum can save water and avoid dangerous levels of dehydration by letting its body temperature rise with the heat.