Molecular Correlates of Life History Trade-offs

摘要

The life history trade off between longevity and reproduction is seen in a variety of animals. It has been found in the model organism Drosophila melanogaster that regulation of lifespan and reproduction rates are linked with various ratios of protein to carbohydrate diet ingested by the flies throughout their lifetime. Dietary Restriction and its effects on lifespan have been studied for many years, with consistent results seen between vastly different organisms. Restriction of caloric intake is known to extend lifespan in these different organisms. Initially called Caloric Restriction, it has been shown in Drosophila that isocaloric diets of yeast (as a protein source) and sugar, in varying ratios, results in organisms portraying the typical trade-off between lifespan and reproduction, implying that it is macronutrient status rather than caloric restriction that is extending lifespan. When given the option, Drosophila are able to self regulate diet intake and maximise lifetime reproduction.