Figure 1. Changing dietary protein and carbohydrate concentrations modify Drosophila lifespan and fecundity.

(a, b) Lifespan was maximised at our intermediate dose of dietary protein (carbohydrate fixed at 17.1 g/l) but was unaffected by our carbohydrate (c, d) concentration range (protein fixed at 9.7 g/l). (b) Cumulative egg production had a significant positive relationship with protein levels and (d) significant negative correlation with dietary carbohydrate content. Note that the intermediate protein and carbohydrate diet (9.7 g/l protein, 17.1 g/l carbohydrate) is common to both nutrient dilution series. The median survival data in panels (b) and (d) represent data from replicates that are combined in panels (a) and (c), respectively. (b,d) Cumulative eggs laid per female are represented as triangles while median survival (days) are shown as circles. Statistical analysis reported in Supplementary files 1 and 2.