Organisms are expected to act in ways that enhance the transfer of their genes to future generations. Thus, the apparent suicide (apoptotic death) observed in many species of single celled organisms including yeast and bacteria present a conundrum to evolutionary biologists. Why would natural selection favour an organism that kills itself? One explanation is that a gene for suicide may spread in a population through kin selection if the death of the focal individual enhances the fitness of related individuals.  Apoptosis in Chlamydomonas is known to be triggered by UV exposure, and there is evidence to suggest that chemicals released by apoptotic cells protects other individuals from UV damage. We are exploring this effect to examine whether they may confer protection against other stresses as well, as well as developing methods to assay the level of apoptosis occuring.