mutation accumulation theory

The mutation accumulation theory suggests that as organisms age, harmful genetic mutations gradually build up because natural selection is less effective at removing these mutations in older individuals. Since many traits affecting early life are under stronger evolutionary pressure, mutations impacting later life are less likely to be eliminated. Over time, this accumulation of late-acting mutations contributes to the decline in health and increased likelihood of diseases associated with aging. Essentially, it explains aging as a consequence of the imperfect process of natural selection, which allows some harmful mutations to persist and accumulate in the genome.