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

There are parallels between the effects of laboratory selection and nutriti onal manipulation on the expression of lifespan and other fitness-related c haracters in Drosophila melanogaster, However, little is known about the ef fects of laboratory selection and nutritional manipulation when applied sim ultaneously. Given that D, melanogaster is one of the major model organisms for testing theories of aging, simultaneous application of laboratory sele ction and nutritional manipulation is of considerable interest. To that end , we developed six groups of fivefold replicated population selected for ei ther early or late fertility. Each of these groups was maintained on either high- or low-nutrition diets, Comparisons among Le groups showed that nutr ition is neutral in selecting for lifespan. Moreover, the dietary-restricti on response can he broken by simultaneous selection and nutritional manipul ation. Finally, characters that respond in a parallel manner under selectio n or nutritional manipulation may not when the two ore applied simultaneous ly.