3. Save Water
Humans are clearly not desert creatures. Watery pee, moist dung, and profuse sweating are all hallmarks of a creature from a place where fresh water isn't scarce. But what happens if we start to run short of precious life-giving water? Again, the body comes to its own rescue. Constipation is a common accompaniment to a desert survival scenario. So is dark, concentrated urine. And over time, most people can adapt to slim rations of water—if they ease into it. When Steven Callahan was adrift in a life raft in the Atlantic in 1981, he subsisted on one pint of rainwater a day for the last 30 days of his 76 day ordeal, and lived to tell the tale.