The Energetics of r- vs. K-selection in Two African Strains of Aedes aegypti1

Abstract

Two strains of the mosquito Aedes aegypti obtained in Tanzania in 1971 from a village habitat (House) and a feral habitat (Bamboo) only 100 meters apart demonstrated differences in both their physiological and population ecology, suggesting some genetic isolation between them. Their population attributes indicate that House is more r-selected and Bamboo is more K-selected. Measurements of respiration indicate that despite a number of differences between the strains, the energy cost of the immature part of the life cycle is essentially the same for both of them. However each strain has adopted a different strategy in using this energy: in Bamboo more is incorporated into biomass, while in House more goes to maintaining the life cycle. The immature life cycle proceeds more rapidly in House. These observations suggest a generalization that for similar organisms differing life table strategies may be employed but only to the extent that an apparently definite energy cost is paid.