High altitudes are physiologically challenging: the hypobaric hypoxia, cold, and increased ultraviolet radiation mean humans ascending to high altitude faster than they acclimatize risk life-threatening illnesses. Despite such challenges, birds can thrive at high altitudes and some even complete metabolically costly migrations across the world's highest mountain ranges. We outline the aspects of avian anatomy and physiology that confer advantages at each level of the oxygen transport cascade and compare them with those of human and nonhuman mammals. We also discuss additional adaptations that have been described for high-altitude specialist species of birds and how these are mirrored in high-altitude adapted mammals.

中文翻译：

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天然登山者：高海拔地区鸟类生理学的见解。

高海拔地区在生理上具有挑战性：低压缺氧，寒冷和紫外线辐射增加，意味着人们爬升到高海拔地区的速度快于他们适应威胁生命危险的疾病的速度。尽管存在这些挑战，鸟类仍可以在高海拔地区繁衍生息，甚至有一些鸟类在全球最高山脉上完成了新陈代谢代价高昂的迁徙。我们概述了在氧气输送级联的每个水平上都具有优势的禽类解剖学和生理学方面，并将其与人类和非人类哺乳动物的优势进行了比较。我们还将讨论已针对高海拔特种鸟类描述的其他适应措施，以及在高海拔适应的哺乳动物中如何反映这些适应措施。