The effects of altitudinal variation in Ethiopian populations

Abstract

A study has been made of three neighbouring populations living at 1500, 3000 and 3700 m in the northern Simien of Ethiopia. The environments of these populations not only differ in many climatic elements, but also probably in nutritional factors and exposure to infections. The growth and physique of the people vary with altitude and the lowlanders (at 1500 m) tend to have a more linear body build. Differences in chest dimensions can be related to functional differences in respiratory physiology, since the highland groups, both male and female, have larger forced expiratory volumes and forced vital capacities as compared with the lowlanders. The relationships between these measures of respiratory function and age, stature and weight also tend to be dependent on altitude, but in all the Ethiopian groups there is a closer relationship between body weight and respiratory capacity than in other populations. This distinctiveness is probably due to the characteristics of Ethiopian physique. A slight polycythaemia and elevated packed cell volume are evident in the highland groups but, unexpectedly, there is some evidence that at least at the time of the expedition the haemoglobin concentrations were lower. The highlanders also show a raised systolic blood pressure. Blood-group and demographic data suggest that the various populations are probably genetically very similar, and the findings are discussed in terms of physiological and developmental adaptability.

The Distribution in Human Populations of Electrophoretic Variants of Cytoplasmic Malate Dehydrogenase

“…The slow type of D avidson and C o r tn er [6], hitherto confined to a single American Negro family, has not been found where we expected to find it, in any of the numerous African Negro populations which we have tested, but only in the Amhara of Ethiopia who on the basis of their physical type and blood groups [10] appear to be of mixed Negroid and MediterraneanCaucasoid descent. The present finding suggests that among their ancestors is some rather specialised African population which was represented, but only slightly so, among the slaves deported to America.…”

The Distribution in Man of Genetic Variants of 6-Phosphogluconate Dehydrogenase

“…One of the first series of populations which we tested belonged to the Amhara of Ethiopia, H a r r is o n et al [17]. Two groups of people were tested, one living at 1,500 m and one at 3,000 m. Their 6-PGD frequencies were significantly different: 5.8, 1 df., 0.01 < P <0.02, but as tests for more than 20 systems were carried out, it could be expected that one of them would by chance alone show apparently of Genetic Variants of 6-Phosphogluconate Dehydrogenase 527 significant differences between the populations at the 5% level.…”

Adventures in Human Population Biology

“…Genetic and growth projects were initiated among the Quechua and Aymara in Bolivia and Chile as well as in Peru (21). A British study used an interesting migrantresearch design to examine the effects of altitude on growth and health of the Amhara in Ethiopia (19,27). Studies of growth, physiology, and demography were conducted in Nepal (43).…”