Antagonistic pleiotropy is the name given to a particular view on the evolution of aging. Natural selection will favor optimization of capacity in early life, when reproduction is possible, but not the optimization of capacity in late life. Given a system in which the decline of aging is already happening to some degree, there will be further selection of processes that work well at the outset but cause harm later on in life. The adaptive immune system is an example of the type: it is highly effective in youth, due to its capacity for memory, but runs down and malfunctions in the later life context of trying to maintain memory of a lifelong exposure to countless varieties of pathogen.
Researchers here present evidence for the cellular maintenance processes of autophagy to be pleiotropic in this way, at least in nematode worms. In this species autophagy works well in the context of a youthful low level of damage, but then becomes actively harmful in the later life context of high levels of damage and dysfunction. Early life capacity for reproduction has a much greater influence on the traits that are selected than late