The disposable soma theory, proposed by Thomas Kirkwood in 1977 , is one of several theories about ageing. It offers a evolutionary view of the process proposing that age-associated accumulation of cellular damage in individuals is due to an evolutionary tendency to use more energy in reproduction processes instead of repairing and conserving the somatic cells.
1. Kirkwood TB. Evolution of ageing. Nature. 1977 Nov 24;270(563 5):301-4.