ANONYMOUS NICHE. “The only benefit of aging is that it leads to death that creates a vacancy in the niche. This vacancy could be filled by a close relative or a distant relative or no relative at all, an animal that doesn’t age or even an animal of a different species that shares some of the same food species. Kin selection and even MLS models are not promising for evolution of aging.”
http://joshmitteldorf.scienceblog.com/2013/07/22/evolution-of-evolution-and-evolution-of-death/