Often the truth value of a scientific claim is dependent on our faith that laboratory experiments can model nature. When the nature that you are modelling is something as large as the tallest terrestrial mountain on earth, and as mysterious (at least until 1953) as the reaction of the human body to the highest point on the earth's surface, mapping between laboratory and ‘real world’ is a tricky process. The so-called ‘death zone’ of Mount Everest is a liminal space; a change in weather could make the difference between a survivable mountaintop and a site where the human respiratory system cannot maintain basic biological functions. Predicting what would happen to the first human beings to climb that high was therefore literally a matter of life or death – here inaccurate models could kill. Consequently, high-altitude respiratory physiology has prioritized not the laboratory, but the field. A holistic, environmentally situated sort of science used a range of (often non-scientific) expertise to prove the laboratory wrong time after time. In so doing, Everest was constructed paradoxically both as a unique field site which needed to be studied in vivo, and as a ‘natural laboratory’ which could produce generalizable knowledge about the human (male) body.