To keep cool, humans can restrict blood flow and sweat - if water is available, which is why that is critical at high temperatures. The dangers include hypothermia, trench foot, and frostbite - outside the tropics, cold is often as much of a danger as drowning after marine accidents. People can survive surprisingly low temperatures, however, with cases where those long given up for dead have revived. And animals such as penguins , polar bears, and fish have anatomical adaptations to the cold. She provides non-technical explanations of how muscle works, how energy production links such metabolites as ATP, glycogen, lactic acid, and creatine phosphate, and how the oxygen supply works.
Life has to be protected from huge temperature variations, airlessness, and radiation.
As well as practical problems it poses for everyday living, weightlessness affects the balance and induces muscle and bone loss. No attempt is made to link these chapters together, and the topics within chapters are often disconnected - even those not boxed as digressions. Readers will pick up from Life at the Extremes a variety of isolated facts rather than any kind of systematic understanding. Some of these are, however, quite intriguing - for example a brief account of the Ama traditional female divers of Japan. None of this, however, should stop a broad range of people enjoying Life at the Extremes .