Physiological variation and adaptability in human populations

This review traces some of the developments in population physiology based on contributions to the Annals over the last 25 years. Two broad themes are evident, physiological systems variation and adaptation, and by way of int roduction an historical perspective of their relationship within human ecol ogy is explored. Studies of physical fitness and work capacity, and the eff orts to create standardized Field procedures make up a number of the early papers. Longitudinal studies have provided reliable reference standards for Westernized populations, but are virtually non-existent for primitive grou ps. The relative importance of phenotypic and genotypic variations in worki ng capacity have yet to be clearly defined. The level of habitual activity during childhood contributes to the development of ventilatory capacity tho ugh constitutional influences are of major importance. Variability in stren gth and motor performance of skeletal muscles are shown to have a direct be aring on aspects of grow th, development and biological maturation. Physica l and psychological stress in communities have been investigated. These and other studies contribute valuable data on the issue of stress, hypertensio n and cardiovascular morbidity and mortality. On the theme of human adaptab ility, high altitude populations, variations in thermal tolerance and adapt ations in ageing populations have all received recent investigation. Highla nd people of all ages have considerably larger lung volumes than coastal dw ellers. Haematological, biochemical and pulmonary function show adaptive ph enomena that vary in different highland groups. In the tropical biome, more recent work includes the functional consequences of malnutrition, ethnic a nd cultural differences in work capacity, and the effects of endemic diseas e on physical performance. Annals qi Human Biology papers have more recentl y contributed to investigations on morphological and physiological changes with human ageing. Though there is a decline in the ability to adapt to env ironmental stresses with age this may be met by changes in adaptational str ategy in physiological systems.