The social norm of one spouse or significant other in human society may be due to more than just cultural norms, according to a recently published research article from the University of Waterloo. It is likely, according to UW applied mathematics professor Chris Bauch, and co-author of the article Richard McElreath, that monogamy was socially imposed on agricultural societies. </p>
According to the research article, Bauch and McElreath came to this conclusion via “an event-driven, discrete-time agent-based simulation model.” The computer model was programmed to represent individuals in a population that followed inputted rules. Bauch stated, “the predictions of the model unfold naturally from the rules we defined and the resulting interactions between individuals.”
Past research has found populations with polygamous behaviours exhibit higher sexually transmitted disease prevalence than populations of monogamists. Populations that “punished” polygamous groups were found to thrive and facilitated monogamist norms, when conditions allowed it. Bauch and McElreath hypothesized that sexually transmitted diseases decreased polygamous numbers due to infertility, thereby allowing invasions of monogamist groups and the punishment of the polygamous.
The article examined a new hypothesis not previously considered in the field of study; “This is the first time … that this idea has been suggested. The mechanism we explore is consistent with other hypotheses and … many factors supported the emergence of socially imposed monogamy,” said Bauch.
The model used established transmissibility and profiles of syphilis, chlamydia, and gonorrhea to simulate sexually transmitted diseases spread. The simulations ran such that polygamous and monogamous groups were exposed to the sexually transmitted diseases to examine population patterns.
Their results suggest that “the growing prevalence of [sexually transmitted diseases] may have been a factor in the emergence of social imposition of monogamy, coinciding with growing population sizes due to development of agriculture.”
Bauch does not feel that these findings have much relevance to modern sexual dynamics. When asked if his model could predict the spread of this growth of sexually transmitted diseases today, he commented, “No, the model does not include many modern interventions like condoms, testing, and contact tracing.”
