Evolutionary Biology: A Basic Science for Medicine

Abstract

When the Flexner Report was written, evolutionary biology was not yet a well‐developed science and few people were interested in its applications to medicine. As a result, Flexner's recommendations for pre‐medical and medical education did not include evolution. Increasingly, however, physicians and medical scientists are appreciating the clinical relevance of evolutionary biology. The need for antibiotic stewardship to minimize selection for antibiotic resistance and the recognition that cancer is an evolutionary process involving variation and selection among clones of cancer cells have highlighted the urgency of bringing evolutionary principles into medicine. An evolutionary perspective can enhance students' understanding of health and disease in many ways. Evolutionary biology provides an enriched view of variation. Medicine has traditionally considered variations as deviations from a “normal” state. Evolutionary biology recognizes variation, both within populations and between populations, as an important characteristic of biological species. Variation is a prerequisite for selection and, in addition, it provides a defense against the spread of pathogens within populations. This view of variation leads to an understanding of the differences between individual health and population health. The causes of disease in individuals are different from the causes of the incidence of disease in populations. Much of the within‐population variation is genetic while environmental differences are major components of between‐population variation. The focus of medicine on disease in individuals has led to an overemphasis on genetic risk factors and a dependence on pharmacologic therapies. An evolutionary view of population health emphasizes the importance of environmental risk factors or determinants of disease and the possible role of behavioral or cultural interventions in disease prevention. Evolutionary life history theory is an account of the ways in which natural selection has shaped our entire life course. The theory is especially concerned with the acquisition and allocation of metabolic energy and other needed resources. Among other things, we use metabolic energy to build up excess physiological capacities, or reserves, early in development and to prevent or repair the inevitable bodily damage that occurs throughout our lives. Diseases of aging result from unrepaired somatic damage and the depletion of our physiological reserves. This understanding suggests that interventions designed to promote the accumulation of physiological reserves and to slow the accumulation of bodily damage may postpone the onset of diseases of aging. Recognition that signs and symptoms of disease may be adaptations that decrease the fitness loss caused by disease heightens the need for caution in treating the manifestations of disease. These are just a few of the benefits of incorporating evolutionary insights into medicine. Evolutionary biology is a basic science for medicine. Our challenge is to figure out the best ways of integrating evolution into an already overcrowded medical curriculum and of bringing evolution to the attention of busy physicians whose first responsibility is to address the pressing problems of their patients.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.