Primate Aging, Health, and Social Relationships

The global rise in the number of elderly individuals in the human population, coupled with an epidemic of loneliness, emphasizes the need to understand the interaction between aging and sociality. Natural populations of nonhuman primates offer comparative models for studying this complex, bidirectional relationship. We first define aging, identify measures of aging, and emphasize that the pace of aging is heterogeneous across biological systems, individuals, and species. We then review how social relationships vary with age, noting a need for within-individual analyses to test between age-related variation and within-individual aging effects. We next explore how the quality and quantity of social relationships affect healthy aging. We conclude by recommending future research across different primate taxa focused on longitudinal, multidomain measures of aging and within-individual analyses of social aging.