A number of my posts declare that there’s a feedback loop constraining variation from cultural norms and local genetic norms. Here’s one example:

The Face on the Cutting Room Floor

Policing observance of cultural behavior norms makes certain culturally approved traits into positive sexual selection traits. This has the effect of maintaining the status quo of the population and the culture. This is a bit of supporting evidence.

Selection, adaptation, inheritance and design in human culture:
The view from the Price equation

“A number of statements are made recurrently in summarising cultural evolutionary theory. One is that culture is a system of inheritance. Thus, humans have not just the standard one system of inheritance (genetics), but (at least) a second one, culture [5]. We have, in other words, a dual inheritance [3], and two inheritance systems entails two distinct fitnesses, genetic fitness, and cultural fitness. Another statement is that cultural evolution produces design-like properties that would not emerge without it [6,7]. The key insight of Darwinian genetic evolutionary theory was that design-like properties could be produced, over time, by selection processes. Thus, it is quite natural, seeing design-like properties in culture, to assume they must be produced by selection processes too. Still another generalization is that cultural evolution can increase genetic fitness. For example, this claim is implicit in the idea that having a second inheritance system is adaptive for coping with environmental fluctuations faster than those that can be tracked by genetic selection, but slower than those generally tracked by individual learning (see e.g. [8]). ‘Adaptive’ in this context means genetically adaptive—more survival, more babies—and so for the claim to work, cultural evolution would have not only to increase cultural fitness, but genetic fitness too.”  -Daniel Nettle

Download the paper (pdf format)183-preprint