Comparative Biology of Aging

determined by an inability to move in response to touch. C. elegans develop through four larval stages following hatching and prior to adulthood. Adult C. elegans are reproductive for about the rst week of adulthood followed by approximately two weeks of post-reproductive adulthood prior to death. Life span is most commonly measured in the laboratory by maintaining the worms on the surface of a nutrie- agar medium (Nematode Growth Medium, NGM) with E. coli OP50 as the bacterial food source (REF)