The effects of nutritional manipulation and laboratory selection on lifespan in Drosophila melanogaster

There are parallels between the effects of laboratory selection and nutritional manipulation on the expression of lifespan and other fitness-related characters in Drosophila melanogaster. However, little is known about the effects of laboratory selection and nutritional manipulation when applied simultaneously. Given that D. melanogaster is one of the major model organisms for testing theories of aging, simultaneous application of laboratory selection and nutritional manipulation is of considerable interest. To that end we developed six groups of five fold replicated populations selected for either early or late fertility. Each of these groups was maintained on either high- or low-nutrition diets. Comparisons among the groups showed that nutrition is neutral in selecting for lifespan. Moreover, the dietary-restriction response can be broken by simultaneous selection and nutritional manipulation. Finally, characters that respond in a parallel manner under selection or nutritional manipulation may not when the two are applied simultaneously.