Gwern's Algernon Argument is relevant here: https://www.gwern.net/Drug-heuristics
Logically, it's likely there must be trade-offs for higher IQs or it would have been selected for more strongly.
Logically, it's likely there must be trade-offs for higher IQs or it would have been selected for more strongly.
Otherwise we would also all have more muscle mass. There doesn't seem to be much downside to that.
This is helpful because it means we can survive with unpredictable diets. But there might be other benefits like heart health or avoiding cancer.
Another big issue with huge brains is that your babies take longer to develop and are very hard to give birth to.
A significant portion of their development has to be moved outside the safety of the womb or their heads would get them stuck!
I have trouble understanding how people can make this point and still be big believers in (utility of?) IQs. If training for IQ tests destroys their validity they never had much in the first place.