In this episode, we explore how animals and high-altitude human populations have evolved to thrive in low-oxygen environments. We highlight the bar-headed goose’s efficient oxygen transport, the yak’s and Andean camelids’ cardiovascular adaptations, and the diverse genetic strategies of Tibetans, Andeans, and Ethiopians. We also examine the crucian carp’s metabolic flexibility—surviving without oxygen by producing ethanol instead of lactate—and the snow leopard’s and Tibetan fox’s adaptations to cold and hypoxia. These natural strategies offer insight into human high-altitude performance, medical treatment for hypoxia, and resilience in extreme environments.