http://www.pnas.org/content/early/2017/10/25/1618854114 http://www.pnas.org/content/early/2017/10/25/1618854114 "Selection between somatic cells (i.e., interce

http://www.pnas.org/content/early/2017/10/25/1618854114 http://www.pnas.org/content/early/2017/10/25/1618854114 "Selection between somatic cells (i.e., intercellular competition) can delay aging by purging nonfunctioning cells. However, the fitness of a multicellular organism depends not just on how functional its individual cells are but also on how well cells work together. While intercellular competition weeds out nonfunctional cells, it may also select for cells that do not cooperate. Thus, intercellular competition creates an inescapable double bind that makes aging inevitable in multicellular organisms." ... and so you end up getting cancer, sooner or later. Which of course doesn't exclude external interventions, from chemotherapy to resetting your DNA to a previously backed up state.