Intraspecific variation in animal energy and water balances may play an important role in local adaptation of populations to specific habitats such as deserts. We examined Kuhl's pipistrelle (Pipistrellus kuhlii), a common bat in Israel that ranges in distribution from mesic Mediterranean to hyperarid desert habitats, for intraspecific differences in metabolic rate (MR) and evaporative water loss (EWL) among populations along a climatic gradient. We tested the prediction that EWL, especially at high ambient temperatures is lower in Kuhl's pipistrelles from desert habitats than from mesic habitats. We measured MR and total evaporative water loss (TEWL) at four ambient temperatures (10 °C, 20 °C, 30 °C and 35 °C) in three groups of bats using open-flow respirometry. We fitted the bats with a mask to separate cutaneous water loss (CWL) from respiratory water loss (RWL) at 35 °C. At 35 °C, mean TEWL in the southernmost group, from the hyperarid location, was significantly lower than in the other two groups, with no apparent difference in mean MR. The source of difference TEWL was that the southern group had significantly lower CWL than the other two groups; RWL did not differ among them. This suggests that there are mechanisms that reduce EWL from the skin of the bats; a likely candidate is modification of the lipids in the outer layer of the dermis that make the skin possibly less permeable to water as has been described in birds and a few other species of bat.

中文翻译：

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库尔（Kuhl）的花les中的蒸发水分损失沿着环境梯度（从中度到高度干旱）下降。

动物能量和水平衡的种内变化可能在使种群适应沙漠等特定生境的局部适应中发挥重要作用。我们检查了Kuhl的pipistrelle（Pipistrellus kuhlii），这是以色列的一种常见蝙蝠，分布范围从中地中海到高干旱沙漠生境，在气候梯度下各种群的代谢率（MR）和蒸发水分损失（EWL）的种内差异。我们测试了这样的预测：在沙漠环境中，库尔人的叶柄中，特别是在较高的环境温度下，EWL低于中生境。我们使用开放式呼吸测定法在三组蝙蝠的四个环境温度（10°C，20°C，30°C和35°C）下测量了MR和总蒸发水损失（TEWL）。我们在蝙蝠身上戴上口罩，以在35°C时将皮肤失水（CWL）与呼吸失水（RWL）分开。在35°C时，从最干旱的位置开始，最南端组的平均TEWL显着低于其他两组，平均MR没有明显差异。TEWL差异的来源是，南部组的CWL明显低于其他两组。RWL在它们之间没有差异。这表明，有一些机制可以减少蝙蝠皮肤的EWL。一种可能的候选方法是修饰真皮外层中的脂质，使皮肤对水的渗透性可能降低，如鸟类和一些其他种类的蝙蝠中所述。明显低于其他两组，平均MR无明显差异。TEWL差异的来源是，南部组的CWL明显低于其他两组。RWL在它们之间没有差异。这表明，有一些机制可以减少蝙蝠皮肤的EWL。一种可能的候选方法是对真皮外层中的脂质进行修饰，从而使皮肤对水的渗透性降低，如鸟类和一些其他种类的蝙蝠中所述。明显低于其他两组，平均MR无明显差异。TEWL差异的来源是，南部组的CWL明显低于其他两组。RWL在它们之间没有差异。这表明，有一些机制可以减少蝙蝠皮肤的EWL。一种可能的候选方法是对真皮外层中的脂质进行修饰，从而使皮肤对水的渗透性降低，如鸟类和一些其他种类的蝙蝠中所述。