The Role of Parasites in Shaping Human Values

This book presents a synthetic theory of cultural values and history. It expands on a 2012 Behavioral and Brain Sciences target article by the authors, and includes replies to the commentaries. The theory is bold, extensively and rigorously supported, and suitably qualified. This theory needs to be incorporated into analyses of human behavior in a variety of disciplines in the behavioral sciences and history. The gist of the theory is this: In localities where parasites that transmit disease between humans are abundant, people isolate themselves from outsiders, who may carry infectious diseases. These people tend to fear and avoid outsiders and alien values, and to remain philopatric. This self-imposed isolation favors conservative values because the novel values of outsiders are kept at bay. Parasite stress also reduces innovation and cognitive performance by inducing lethargy; the debilitating effect of parasites may help account for the lower IQ of people living in countries and US states with more parasites. Other ramifications of the theory extend to crime, warfare, endogamy, female chastity, and other behavioral phenomena. Thornhill and Fincher support their theory by citing numerous studies of a variety of human populations around the world, past and present. They examine a host of variables, and generally provide statistically strong support for their claims. They address Weisfeld, G. (2019). The Role of Parasites in Shaping Human Values. Human Ethology, 34, 115-117. https://doi.org/10.22330/he/34/115-117