in most cases a genetic explanation is worth less than a socio-cultural one, as cultures change w/o genes.ziel then replied, saying
It happens but very rare. Gene driven change is much more the norm'It' referring, of course, to cultural change in the absence of genetic change, where technological and cultural developments drive humans to do different things.
I find ziel's claim so absurd that I almost can't be bothered to refute it. But let's do it anyway.
Culture, however you define it, includes a lot of things - technologies, cuisine, sexual attitudes, religious beliefs, sayings, superstitions, knowledge of the world, language, song, dance, sculptural tradition, literature... There's a lot to it. Almost none of it is genetically inherited.
You do not inherit your adherence to a religion through your DNA, and the children of staunch Christians and Zoroastrians in Syria and Persia became Muslims so soon after the Islamic conquests that natural selection is not a plausible mechanism. As Richard Dawkins (and plenty of others, of course) has stressed, you get your religion from your cultural milieu and origin, not your genes, and there is fundamentally no such thing as a 'Catholic baby'.
Your language is not inherited genetically; the children of Igbo speakers from Nigeria tend to learn fluent English if they grow up in London or fluent Malay if they grow up in Kuala Lumpur. Your songs and dances are not genetically encoded, and a person from any community in the world could learn to salsa or morris, given sufficient training and inclination.
Your cuisine is not genetically inherited, either, except for a few trivial facets. Lactase persistence is a variable trait in humans; it allows some people to be able to digest lactose, a sugar in animal milk. Lactase persistence clearly has an impact on cuisine and demography, as milk contains a lot of nutrients, including fats and sugars lacking elsewhere, and if you can't digest it, you probably won't want to eat a bowl of cream for pudding (as some Swiss people do).
This is one of the rare examples of genes helping to create cultural differences, and even here humans have found ways around it: In Mongolia, lactose-intolerant pastoralists with huge herds ferment their milk to make airag, yoghurt, and cheese, thereby receiving the economic and nutritional benefits of milk with none of the tummy upsets. You can have a pastoral economy, massive herds, and the necessary technologies and lifestyles to go along with all of that without developing lactase persistence.
In Thailand, where people are equally lactose intolerant, ice cream has become very popular throughout the country; Thai people either use coconut milk in place of cow's milk, or they take medication to help them digest the milk without problems, allowing them to indulge in a cooling, refreshing snack in the tropical heat.
Nearly anybody can learn to use a bow and arrow, and bows and arrows provide significant advantages in procuring food and defending settlements when compared with thrown spears or atlatls. Anybody can learn how to make a fish hook. Anybody can learn to drive a car or ride a horse. This is because culture simply isn't genetically determined.
As for more 'important' things, like literacy - well, you don't really need a gene for it. It seems as if we're all pretty capable of learning how to read and write, barring severe mental impairment.
When Hawaiians were introduced to the concept of writing things down at the end of the eighteenth century, they took to it extremely quickly, and by 1820 the Kingdom of Hawai'i was almost certainly the most literate society in the entire world - going from 0% in 1750 to over 90% in 1820. This is probably because the King was an absolute ruler and wished it so, and it helps that the Hawaiian language has a simple phonology and is therefore easily written in an alphabetic script (it only needs thirteen letters) - but that's precisely the point: cultural conditions put Hawaiian civilization in the right place for writing to take root.
If nineteenth century Hawaiians, like the speakers of Southeastern ǃXuun, a Khoisan language of Namibia, lived in a non-state society and spoke a language with an extremely complex phonology (there are 48 clicks alone in Southeastern !Xuun, and lots and lots of other phonemes besides), then I daresay the situation would be different, as it has indeed proven to be among speakers of Southeastern !Xuun.
You don't inherit the ability to live in a state through your DNA either, and that's quite a big deal in terms of understanding human history. The HBD blogger Jayman claimed, in his ridiculous HBD history of civilization, that northern European barbarians needed genetic changes to acclimatise to civilized life in the wake of the fall of Rome, thereby accounting for the 'dark ages'. This would have been a good example of genes hindering or advancing major cultural changes. In reality, it's an example of the absurdities of applying HBD theory to actual historical fact.
First of all, these days, 'dark ages' is a term nobody uses except HBDers, because it isn't useful and it reflects earlier historiographic prejudices against non-classical European societies. It used to refer to the 'darkness' of Europe in terms of literature, administration, and public records - there are fewer of these from the earliest days of Germanic dominance than at any time in the history of the Roman empire, for instance - not to the total destruction of life and society (because that didn't happen). Europe was 'dark' not because everything was awful (it wasn't - people were probably healthier and longer lived in late antiquity than at the height of the Roman empire), but rather because little in the way of written evidence has survived to shed 'light' on events. And we may explain that circumstance by the simple fact that most Germanic- and Slavic-speaking invaders/migrants were not literate and their social lives didn't initially depend on the written word.
It only took a couple of generations for 'barbarian' northern Europeans to become literate and to develop strong chiefdoms and kingdoms across Europe. The gap between the end of the Roman period and the rise of Frankish and Gothic kingdoms is far too short for selective pressures to have resulted in major changes. We may surmise that the changes took place as changes like that often do - through complex webs of alliances, manipulations, religious oaths, increasing central control of productive farmland and people to work it, introduction of exotic religious and scribal traditions, and so on - not because of some biologically-implausible genetic change.
It should also be pointed out that speakers of Germanic languages do not appear in the literature as entirely wild and uncontrollable - far from it, actually. Tacitus, writing in the late second century CE, noted that warriors in Germanic tribes were so loyal to their leaders that if they died in battle, the warriors would too - something that we can also see at the battles of Maldon (991) and Hastings (1066). Tacitus also speaks favourably of morals, law, and order in Germanic villages. They were not wild and uncontrollable cretins starting from a cultural blank slate.
|A statue of Byrhtnoth, the Anglo-Saxon leader who died surrounded by his men at Maldon. h/t Oxyman.|
A hundred years isn't a very long time in terms of human reproduction; it represents between four and six generations, hardly long enough for genes to account for any of it. Selective pressures are rarely consistent enough for long enough for genetic changes to account for cultural changes, and humans always find ways around such things. The scope for natural selection to effect cultural change is thus limited, and it is the exception for culture to be at the beck and call of genetics rather than the other way around.