Apriori, I’d expect that given how much human dominance is almost entirely dependent on our (collective) intelligence, our evolution would have selected strongly for intelligence until it met diminishing returns to higher intelligence
Evolution is not a magic genie that just gives us what we want.
If there’s strong evolutionary pressure to select for a given trait, the individuals who score poorly on that trait won’t reproduce. The fact that we see big IQ differences within natives of the same country is a sign that the evolutionary selection for IQ isn’t very strong.
Most mutations reduce the performance of an organism. If you have a mutation that makes it 1% less likely that a person reproduces it takes a lot of time for that mutation to disappear due to natural selection.
Given that we see that IQ generally correlates with other positive metrics. I think it’s plausible that more than half of the IQ difference between natives of the same country is due to such mutations that provide no fitness advantages. If you believe that there’s very strong selection for IQ than you would expect even more of the IQ differences to be driven by constantly new appearing useless mutations.
In such a scenario I would not expect the smartest humans to have no useless mutations at all but just fewer than the average person. As our knowledge about genes and our ability to do gene editing without producing additional errors evolves it’s likely that we will see experiments in growing humans that are smarter than anyone currently alive.
Human brains already consume 15%-20% of the calories which is a lot more than most other mammals. It’s not as easy to raise that amount given that it competes with other uses for energy.
Wikipedia suggests 50,000–150,000 years since human adopted language and thus intelligence became more important. That’s not a lot of time to come up with alternative ways to organize the cortex to be more efficient.
Evolution is not a magic genie that just gives us what we want.
If there’s strong evolutionary pressure to select for a given trait, the individuals who score poorly on that trait won’t reproduce. The fact that we see big IQ differences within natives of the same country is a sign that the evolutionary selection for IQ isn’t very strong.
Most mutations reduce the performance of an organism. If you have a mutation that makes it 1% less likely that a person reproduces it takes a lot of time for that mutation to disappear due to natural selection.
Given that we see that IQ generally correlates with other positive metrics. I think it’s plausible that more than half of the IQ difference between natives of the same country is due to such mutations that provide no fitness advantages. If you believe that there’s very strong selection for IQ than you would expect even more of the IQ differences to be driven by constantly new appearing useless mutations.
In such a scenario I would not expect the smartest humans to have no useless mutations at all but just fewer than the average person. As our knowledge about genes and our ability to do gene editing without producing additional errors evolves it’s likely that we will see experiments in growing humans that are smarter than anyone currently alive.
Human brains already consume 15%-20% of the calories which is a lot more than most other mammals. It’s not as easy to raise that amount given that it competes with other uses for energy.
Wikipedia suggests 50,000–150,000 years since human adopted language and thus intelligence became more important. That’s not a lot of time to come up with alternative ways to organize the cortex to be more efficient.