Senescence, the age related decline in physiological performance, is reflected in a number of traits including fecundity, susceptibility to disease, agility, and mobility.  When senescence is observed in an organism, it is not clear if there is a general decline in function across all traits or if certain traits decline at different rates.  My project investigates the effects of age on a host of quantitative traits including: immune response, fecundity (reproduction), triglyceride level (energy storage), and lifespan in the fruit fly, Drosophila melanogaster.