Life expectancy is variable in many organisms, including laboratory strains of C. elegans that are isogenic. My group is focused on understanding the causes the underly the variability in lifespan. This variability may stem from both very early differences among individuals and/or from the passive and progressive accumulation of damage. We are studying how the inter-individual variability in the activity of the longevity pathways affect the rate at which each individual ages. We are using genetics, molecular biology and systems biology approaches to link gene-expression with lifespan variability.