Rethinking the Evolution of Ageing: From Mutation Accumulation to Social Transfers and Negligible Senescence

Abstract

The theory of aging explains why death becomes more common as individuals grow older. It suggests that as we age, the remaining years available for repro- duction decrease, making our survival less important for passing on our genes. However, with recent developments, it has been observed that general theories do not adequately account for the lives of social animals. Successful reproduction in these animals involves not only having children but also providing support to them and other younger individuals. Over time, several theories have been devel- oped to combine the effects of fertility and support in determining mortality at different ages. For species that strike the right balance between producing many offspring and investing in each one, the factor of support becomes more influen- tial in mortality. By integrating transfers with fertility-based selection, a formal theory has been developed that aligns with data and applies to understanding life histories and population dynamics. This review also highlights how social insects do not conform to classical theories of aging and emphasizes the need to consider recent models of aging theories that address this limitation.