What you need to know about human evolution is how long generation time we have. Genetic scientists count 25 years as a human generation. This is the average difference in age between parents and children over many societies. I think it mostly holds true for the last tens of thousands of years. At least it applies for most of the ancestors of the current humanity since the start of the last ice age.
Modern humans have had children with Neanderthals and Denisovans. The later are so newly discovered we don’t know much about them. But the Neanderthals are known to have grown up one third faster. So they ought to have had a generation time of 19 years or so. Hybrids between them and us had children with one parent’s species. The more the descendants interbreed with this one the more similar their generation time become. Same thing applies to hybrids between us and the Denisovans. Moreover, the hybridization happened more than 40,000 years ago. This is long enough ago for evolution to get rid of most of the dysfunctional.
Evolution needs at least 1,000 generations to change the human brain in any crucial way. That is the equivalent of 25,000 years. As such it is much longer than the lifetime of any human culture. Within the ice ages there were changes in how much colder it was. These changes took place over decades, 2,000 – 5,000 years apart. This means no culture could survive longer than that. The time since the development of agriculture I think is 12,000 years at most. It is still less than half the time evolution would need. Consequentially, our brains are not adopted to life in agrarian society. Much less are we adopted to agrarian state societies. This is not just about incapacity to handle absolute power. I here list some examples which I happen to know about:
Circadian rhythm: In agrarian societies, people as a rule had to get up early in the morning. This just in order to be able to work as much as possible while the sun was up. Then they went to bed within two hours after sunset. But most people’s circadian rhythm is not adopted to this life. It is just one fourth of humanity which are naturally morning people. No, this is not a matter of training. The only result is constantly struggling against one’s inborn tendencies.
Fertility out of pace with sexuality: Girls can in principle get pregnant from two weeks before menarche. However, this happens as early as the age of twelve on average. Then their hips are too narrow for them to give birth safely. Usually, they don’t want to have sex before their hips are wide enough. Which is not the case until they are 14 – 15. In contrast, boys the same age are more or less sex-obsessed. On the other hand, they are rarely fertile before 15 – 16 years of age. Such discrepancies only work if consensual sex is the norm. But in a society where girls are handed over to adult men to sexually exploit shortly after menarche? The consequence of such a practice is an extremely high maternal mortality. All different agrarian state societies of cause did not have this usage. But it commonly occurred.
Learning capacity: In agrarian state societies most people are too preoccupied with their physical survival to have time to learn much. In particular they did not have time and energy to learn to know their fellow beings. The few ones which had this oftentimes lacked contact with equals. So for centuries or millennia almost everyone lacked insight in each other. But we are still capable of learning to know each other. If we just get a chance, I count on us doing this. Before the development of agriculture this was a crucial life skill.
Working capacity: Before the development of agriculture people did not in fact work that much. I think it was 40 – 44 hours a week including housework. Agriculture increased this substantially, but I don’t know by how much. Add a state society without rules of how much you work. Then people can be forced to work for 72 – 84 hours a week. Nowadays it is considered unhealthy to work more than 60 hours a week. Adding housework to the later one likely sums up to 72 – 84 hours a week in this case too. Which means we have not adopted to working that much.
Another consequence of the slowness of evolution is the ability to read and write. We still don’t have any system in our brains specially adopted to this purpose. Instead, we have to connect several different systems to compensate for that. This may be the key to why literates are smarter than illiterates. It trains us in connecting the different capacities we naturally have.
Uploaded on the 14th of Mars 2023.
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