Testing life history theory in a contemporary African population

Abstract

There is accumulating evidence that the evolutionary trade-off between body maintenance and fertility is also present in humans. Several studies have shown this trade-off in historic data sets. Other studies found no evidence for the trade-off. This could, in part, be explained by the fact that the populations under study resided in a modern affluent environment characterized by low mortality and fertility rates, i.e. having past the epidemiologic transition. Lycett et al for instance demonstrated that the trade-off was stronger under conditions of poverty. Accordingly, it has been shown, that the trade-off disappeared in the British aristocracy when environmental conditions markedly improved after 1700 and initiated a demographic transition. Similar trends over time were found in other studies. The objective of this thesis was to test the hypothesis that fertility trades off with early survival in a contemporary population that is still exposed to adverse environmental conditions. Therefore all the studies were performed in the upper east region of Ghana, Africa. The results can be divided into two parts. Part A, Chapters 2, 3 and 4, describes the research population analyzes whether or not the epidemiologic transition has taken place. Part B, Chapters 5, 6 and 7, describes the actual testing of the hypothesis.