Certain perspectives of morphological and functional diversities molded to adapt to highly technological environments remain to be evaluated, which leads us to consider what a truly healthy and comfortable environment is by focusing on the diversity of human adaptability based on the keywords of physiological anthropology, or physiological polymorphism, functional potentiality and whole body coordination. Each of the three keywords is outlined here, as well as the mutual relationship between them. A re-evaluation of the significance of polymorphism in the current living environment is also discussed here.