What matters is today and moving forward, including manmade brain shrinkage in specific demographics today.
Frankly, I did not know about 16,000 to 10,000 years ago, but we now have research to demonstrate how a child’s brain by the age of five growing up in poverty today is about the size of tennis ball smaller than children of the same age growing up without money problems.
You see, poverty is not just a money problem. Poverty significantly decreases the wide variety of experiences a child needs to encounter for the brain to grow to full capacity. Meaning, poverty has a direct impact on brain development, with scans now demonstrating the smaller size. So, there is no need to travel back in time to understand the systemic erosion of human capacity from capitalism subjugated only to a self-serving oligarchy.
Human excellence this is not. An urgent reason why we must reinvent the operating-systems of humanity, including the Neanderthal version of capitalism that artificially and thus unjustly separates the haves from the have-nots.