| Whoa... whoa... let's unpack all the intense presuppositions you're packing in here: "Domestication" is just a word for a natural evolutionary processes in a symbiotic system. The concept that "domestication" is like, actually a thing apart from evolution is a vastly more difficult idea to parse than it appears on it's face. >Domesticated animals are all dumber than their wild counterparts. I mean... again... there are so many things to unpack here. What do we mean by "dumb" and which parts of the brain are being used, and how their size relates to their usefulness. I think it would be extremely difficult to argue any of these claims on their face beyond: small brain -> less brain function, which is extremely spurious. Homo neanderthalensis had notably larger brains than us, yet they did not survive. Hardly an argument for the idea of greater intelligence -> greater brain size. AFAIK, specific areas in the prefrontal cortex is the primary point of interest when it comes to intelligence, and it's a relatively small section of the brain compared, say, to the visual cortex. https://www.discovermagazine.com/planet-earth/neanderthal-br... Finally... the most absurd of all the ideas packed in here is that natural selection for smaller brain size would even be a thing. Human mating is openly available for study, I see little-to-no argument for this being plausible beyond some sort of idiocracy world (is this the domestication thesis you hold? I see in the article they are treated separately), which is genuinely problematic. Possibly that certain types of brain sizes are predisposed to certain behavioral patterns. However, the idea that there is even a single evolutionary pattern for billions of humans is pretty ridiculous. We don't have evolutionary islands like other animals do. |
In mammals, there is a well-established "domestication syndrome" with a specific proposed underlying mechanism and associated symptoms, including many observed in humans in comparison with other hominids (smaller jaws/muzzles, smaller teeth, smaller brain, greater docility). See https://www.genetics.org/content/197/3/795#skip-link for more information.