1. Department of Biochemistry and Biophysics, University of California at San Francisco, California 94143-0448, USA

Correspondence to: Cynthia Kenyon Correspondence and requests for materials should be addressed to C.K. (e-mail: Email: ckenyon@biochem.ucsf.edu).

Caenorhabditis elegans senses environmental signals through ciliated sensory neurons located primarily in sensory organs in the head and tail. Cilia function as sensory receptors, and mutants with defective sensory cilia have impaired sensory perception^{1, 2}. Cilia are membrane-bound microtubule-based structures and in C. elegans are only found at the dendritic endings of sensory neurons³. Here we show that mutations that cause defects in sensory cilia or their support cells, or in sensory signal transduction, extend lifespan. Our findings imply that sensory perception regulates the lifespan of this animal, and suggest that in nature, its lifespan may be regulated by environmental cues.