Evolutionary explanations in medical and health profession courses: are you answering your students' "why" questions?

This paper contrasts the differences between these two types of explanations by describing principles of natural selection that underlie medical questions. Thus, why is human birth complicated? Why does sickle cell anemia exist? Why do we show symptoms like fever, diarrhea, and coughing when we have infection? Why do we suffer from ubiquitous age-related diseases like arteriosclerosis, Alzheimer's and others? Why are chronic diseases like type II diabetes and obesity so prevalent in modern society? Why hasn't natural selection eliminated the genes that cause common genetic diseases like hemochromatosis, cystic fibrosis, Tay sachs, PKU and others?In giving students evolutionary explanations professors should underscore principles of natural selection, since these can be generalized for the analysis of many medical questions. From a research perspective, natural selection seems central to leading hypotheses of obesity and type II diabetes and might very well explain the occurrence of certain common genetic diseases like cystic fibrosis, hemochromatosis, Tay sachs, Fragile X syndrome, G6PD and others because of their compensating advantages. Furthermore, armed with evolutionary explanations, health care professionals can bring practical benefits to patients by treating their symptoms of infection more specifically and judiciously. They might also help curtail the evolutionary arms race between pathogens and antibiotic defenses.The science of Darwinian or Evolutionary Medicine was formalized in the early 1990s most notably by the eminent evolutionary biologist George C. Williams and the physician and professor Randolph Nesse [1,2]. Its methodologies and aims are directed at the scientific investigation of evolutionary causes for human disease, disorders, malfunctions and apparent design failures in order to improve health care and to stimulate fruitful research directions.To clarify what we mean by evolutionary causes it is useful to make a distinction from a different