However, recently “cultural evolution” has slipped, without much consideration, into a much stronger meaning.
For example, in his commentary on Ross Douthat’s article on gay marriage, Tumblr user severnayazemlya writes: What Douthat is saying is that there was some system that existed sometime in the past that was more human-shaped than Marcotte’s vision for the future. The conservative argument is that the cultural inheritance that the past hands down to the present is more human-shaped than most reforms proposed in the present – because there were reformers in the past, and, absent major breaks in the continuity, past reforms have had time to be tested for their fit: those that worked were kept, and those that didn’t were discarded.
[The Lost European Explorer] experiment has been repeated many times when European explorers were stranded in an unfamiliar habitat.
Presumably, the Inuit neither conducted deliberate centralized experiments to determine what food in their area was edible, nor derived the information from explicit understanding of the principles of nutrition.
Rather, over thousands of years, various proposals like “eat those yummy-looking red berries that grow on the small bushes” and “always hunt seals in large groups” were accidentally tested, with the successful ones spreading until they became universal tradition and the disastrous ones being warned against as taboo.
This is fine, but they might get killed in a car accident before their tenth birthday, or be too ugly to find a partner, or get an infectious disease anyway because 1% less risk isn’t really much less risk.
If my child survives, and passes her mutation on to millions of other people all with their randomly distributed level of other good and bad genes and good and bad luck, then maybe eventually over thousands of generations, people with the new beneficial mutation will take over from people without it.
So in principle this kind of intercultural selection could happen. Evolutionary biology has a lot of equations to calculate how long it will take a positively-selected trait to spread.
It depends on a lot of different things, but the most salient here are the length of a generation for the affected organism, and the extent of the selective advantage conferred by the trait. Rome lasted a thousand years, Byzantium another thousand.
Out of pure self-interest, she decides not to eat them again, and tells her friends the same.
Also out of self-interest, they decide not to eat them; those who think they can get away with eating them anyway are quickly disabused of the notion. Any claim that cultural evolution argues against gay marriage because it’s bad for the actual gay-married person must face the fact that actually gay-married people seem totally okay with it, and in fact are urging their friends to do it, the exact opposite of the red berry situation.
On the other hand, both Greece and Rome took over Israel at various points; various Jewish texts record that during that time a lot of Jews were defecting to Greco-Roman culture and there were precious few defections the other way.
It would seem that all of the other differences between Greco-Roman and Judeo-Christian culture – theology, non-sexual mores, geography, technology, philosophy – had a lot more effect than the sexual mores.
In the same way, it’s plausible that cultures might evolve strong internal defenses against actions that are fun but Weaken Moral Fabric, and sure enough we find that everything halfway enjoyable comes with a lecture from our elders about Why We Shouldn’t Do It.