Evolutionary medicine
>
Evolutionary medicine or Darwinian medicine is the application of modern evolutionary theory to understanding health and disease. Wikipedia
Frequency-dependent morphs: The two sexes / Different blood and immune system types
Functioning adaptation (adaptive defense): Fever / Vomiting; (functional responses to infection or ingestion of toxins)
Mismatch between ancestral & current environments: Modern diet-related Type 2 Diabetes
Possible cause: Physiological Dysfunction