Evolution of senescence: late survival sacrificed for reproduction.

摘要: In so far as it is associated with declining fertility and increasing mortality, senescence directly detrimental to reproductive success. Natural selection should therefore act in the direction of postponing or eliminating from life history. The widespread occurrence explained by observing that (i) force natural generally weaker at late ages than early ages, (ii) acquisition greater longevity usually involves some cost. Two convergent theories are ‘antagonistic pleiotropy’ theory, based population genetics, ‘disposable soma’ physiological ecology. antagonistic pleiotropy theory proposes certain alleles favoured because beneficial effects also have deleterious later effects. disposable soma suggests competing demands reproduction less effort invested maintenance somatic tissues necessary for indefinite survival.