How Weak Is Cultural Evolution?

World fertility decline seems the clearest example of a maladaptive cultural trend, as healthy biological species just don’t decline in times of plenty, peace, and health. Two main theories compete to explain this trend. One is that previously adaptive habits have turned maladaptive by misfiring on cues that longer track the adaptiveness as they once did. The other is that the cultural evolution process has become much weaker than it was up until a few centuries ago, which both slows the rate at which misfirings can be corrected, and also allows for more maladaptive changes to norms, via random walks and reversion to natural habits encoded more deeply in DNA.

Here are nine suggested misfiring stories:

1. Contraception allows us to satisfy usual norms re fun, mating w/ fewer kids

2. Pursuit of status markers induce urbanity, long education, conflict w/ kids

3. Freedom is status markers, but having more induces fewer kids

4. Modern media shows high status in detail, raising expectations

5. Pensions replace kids to give old age security

6. Super-stimuli makes fun more engaging, distracts from kids

7. Loss of kin living close makes parenting harder

8. Urban density makes it seem like overpopulation

9. Indoor life messes w/ light, activity rhythms

I asked 5 LLMs to estimate the factor of how much faster such misfirings would be corrected now if our cultural evolution process for group norms was as healthy and robust as it has been through most of human history up until a few centuries ago:

So middle estimate of ~5.5. Stuff that would once been corrected in ~50yrs will now take ~275yrs. Culture is indeed broken.