Previous literature noted that relations between cultural complexity and sexual norms are not very strong, see e.g. here, here and here.

I wanted to have a closer look at this myself in the Standard Cross-Cultural Sample (SCCS). The SCCS is a dataset with societies chosen as natural and unrelated as possible. They need to be unrelated such that statistics based on it are not biased toward cultural things that have been borrowed or inherted more often than others (the so called Galton's problem). Borrowed and inherited things may not necessarily reflect their likelihood of being naturally evolved and hence not necessarily group fitness. Note that there are objections that Galton's problem is likely still not solved in the SCCS, but let's ignore this for now. Dataset: http://eclectic.ss.uci.edu/~drwhite/sccs/

Codebook: http://eclectic.ss.uci.edu/~drwhite/courses/SCCCodes.htm


Figure 1. Cultural complexity and female premarital norms. https://i.imgur.com/gqUgUdp.png

Figure 2. Cultural complexity and homosexuality norms. https://i.imgur.com/AXExtro.png

Figure 3: Cultural complexity and % of married men with more than one wife. https://i.imgur.com/FaoAUrF.png

For clarity, that's variable 158.1.Modernization SUM OF CULTURAL COMPLEXITY (v149-v158).

Shades of red indicate how strictly the offspring is socialized.

Of course, correlation is not causation, but it is still interesting to analyze. One clear pattern is that cultures who completely permitted female premarital sex, homosexuality or had lots of polygyny, never achieved high cultural complexity. Though one can also see that cultures with fairly mild norms could still achieve high complexity. It is also true that very strict norms do not guarantee high complexity at all.


So let's take a closer look at those six outliers with very relaxed norms for female premarital sex (expected to mildly disapproved) but high cultural complexity: Hausa, Burmese, Vietnamese, Javanese, Balinese and Haitians

What all of them have in common:

  • Very hot tropical climates, mostly South Asians (Austronesians). They all have high cultural complexity with their own money, writing systems, schooling, administration, art, social stratification, laws, elections etc. None of them have technology beyond basic metal working (but that's advanced among the societies in the SCCS).

  • None of them depend on gathering or hunting, instead, they mostly live from farming (cereal crops). Very peaceful. Few notions of male bravery etc., low male sexual aggressiveness, males are not socialized very much to be competitive. No slaves, few conflicts and wars. Women are not seen as much inferior and are admitted many rights. Lack of virginity is not grounds for divorce.

  • All of them are very religious with strong superstition about gods who punish by illness and misfortune (this may be related to malaria being common).

  • Percent of men with more than one wife range from 40% (Hausa), 25% (Haitians), 18% (Balinese), to nearly 0% (Burmese, Javanese).

  • In all of them you find typical occupational gender differences, though, which are present in basically all SCCS cultures: Men nearly exclusively work in house construction and metal work, are in charge of the military, wheras women are much more involved in cooking and tasks near the home. Women produce goods, partly work in agriculture, but men could still easily satisfy women's hypergamous preferences as they could gain status in resource extraction that women could not.


The biggest outlier among the six people is the Balinese people as they are the only society that tolerated female premarital sex and where it was universally done, yet achieved very high cultural complexity.

This video provides a fairly good impression of the Balinese people: https://youtu.be/7l5_xLxboxc?t=1922 (NSFW)

The people of Bali strive for perfect poise and balance in every posture, gait and gesture; attempt to maintain orientation both spatially and socially; seek perfect fitness of speech, posture and manner in all situations; and are well developed emotionally and expressive of their emotions. Although there are occasional deviants, most individuals conform to tradition to a high degree. The behavior of the Balinese is characterized by ease and relaxation. They differ from most peoples in that they work in relaxation and experience strain and tension only in their recreation. Their freedom and relaxation seem to come from the immutability of their laws of conduct, the rightness of which is never doubted. The only responsibility of the individual is obedience to these laws.

https://psycnet.apa.org/record/1936-02090-001

Provided that 18% of Balinese men had more than one wife and sex norms were very relaxed, it raises the question how they kept envious beta & omega males in check, enough that they posed no threat to the highly complex culture. Perhaps the relatively strict laws and religion accomplished that (which interestingly did not go along with very strict socialization or sexual norms, though of course they had norms, e.g. women could show breasts, but not their thighs).