You mean to say that the human body was virtually “finished evolving” 200,000 years ago, thereby laying the groundwork for cultural optimization which took over form that point? Henrich’s thesis of gene-culture coevolution contrasts with this view and I find it to be much more likely to be true. For example, the former thesis posits that humans lost a massive amount of muscle strength (relative to, say, chimpanzees) over many generations and only once that process had been virtually “completed”, started to compensate by throwing rocks or making spears when hunting other animals, requiring much less muscle strength than direct engagement. This begs the question, how did our ancestors survive in the time when muscle strength had already significantly decreased, but tool usage did not exist yet? Henrich’s thesis answers this by saying that such a time did not exist; throwing rocks came first, which provided the evolutionary incentive for our ancestors to expend less energy on growing muscles (since throwing rocks suffices for survival and requires less muscle strength). The subsequent invention of spears provided further incentive for muscles to grow even weaker.
There are many more examples to make that are like the one above. Perhaps the most important one is that as the amount of culture grows (also including things like rudimentary language and music), a larger brain has an advantage because it can learn more and more quickly (as also evidenced by the LLM scaling laws). Without culture, this evolutionary incentive for larger brains is much weaker.
In a sense, evolution never stops, but yes the capacity to make tools was way later than the physical optimizations that used the tools.
More generally, an even earlier force for bigger brains probably comes from both cooking food and social modeling in groups, but yes language and culture do help at the margin.
What do you make of feral children like Genie? While there are not many counterfactuals to cultural learning—probably mostly because depriving children of cultural learning is considered highly immoral—feral children do provide strong evidence that humans that are deprived of cultural learning do not come close to being functional adults. Additionally, it seems obvious that people who do not receive certain training, e.g., those who do not learn math or who do not learn carpentry, generally have low capability in that domain.
I actually think this is reasonably strong evidence for some form of cultural learning, thanks.
In a sense, evolution never stops, but yes the capacity to make tools was way later than the physical optimizations that used the tools.
More generally, an even earlier force for bigger brains probably comes from both cooking food and social modeling in groups, but yes language and culture do help at the margin.
I actually think this is reasonably strong evidence for some form of cultural learning, thanks.