ABSTRACT
This chapter cites findings from these disciplines to describe biologic responses to the environment — specifically, to climate, high altitude, and diet. Climate, altitude, diet, and disease are the major environmental stressors that affect large numbers of people and produce changes that can mimic racial variation. Susceptibility to heat stress is influenced by climatic experience, race, body build, physical fitness, age, and sex. Heat cramp and heat exhaustion are less serious consequences of heat stress. Susceptibility to cold stress is influenced by the same factors as with heat stress — climatic experience, race, body build, physical fitness, age, and sex. Children may increase their metabolic rates in response to cold stress more than adults, in compensation for their still-developing cold responses. Adaptation to high altitude is best in individuals whose ancestors have lived at high altitudes enough generations for natural selection to have occurred. Diets are in good part responsible for the worldwide age patterns of morbidity and mortality.
