Affiliations: 1) California State University, Fullerton, CA; 2) Oregon State University, Corvallis, Oregon
Keywords: h. selection; c. innate immunity
Theoretically a result of declining forces of natural selection, aging is a decline in fitness characters. Previous research has established Drosophila melanogaster as a model system to study the evolution of aging. Investigations utilizing experimental evolution have revealed a few well-defined relationships between aging and other traits, but the evolutionary relationship between longevity and immune defense remains unclear. While some studies suggest an evolutionary trade-off between these traits, others suggest positive correlations. Through a 10-fold replicated experimental evolution study, we have created populations that are diverged in age-of-reproduction. Late reproducing populations have evolved increased longevity and also improved immunity against the fungal pathogen Beauveria bassiana. We will test these populations for divergence in immunity against other pathogens. Analyses of whole-genome sequences throughout the selection process will provide information both about causative alleles and about their trajectories of change. Moreover, whole-genome comparison of our populations will reveal genetic connections between longevity and immunity. Advances in healthcare and technology have reduced the impact of many diseases on human populations, but consequently the percentage of people living to late age have increased along with the number of people with age-related illnesses. Aging and associated changes to immunity have become global health concerns which are best understood in the context of evolution.