Chapter 2

Four classes of influences--Physical effects of environment--Stature and environment--Effects of dominant activities--Physical effects of climate--Pigmentation in relation to heat and light--Pigmentation and altitude--Difficulty of generalization from geographic distribution--Psychical effects--In Religion--In mind and character--In language--The great man in history--Economic and social effects--Size of the social group--Effects on movements of peoples--Segregation and accessibility--Change of habitat.