> I question whether intelligence is so helpful that all mammals evolved
> to be as intelligent as possible. It seems to me that intelligence is
> of questionable value in the day to day life of an animal.
> Consider the life of prehistoric humans. I don't see why someone
> marginally more intelligent than others will have much of an advantage in
> hunting or gathering. Most of what is needed is learned culturally, and
> those techniques have been optimized over generations to approximate local
Learning things culturally takes intelligence.
> Sure, even ten or twenty thousand years someone domesticates
> a new animal or discovers fire, but these events are so rare they can't
> have any significant evolutionary input.
The discovery of fire is a good example. Fire was probably discovered a large number of times before the invention caught on. And when it did catch on, I imagine that for quite a few generations, that the leading cause of death was fire safety related. Until the point that people too stupid to use fire safely were weeded out of the population.
> My feeling is that people stumbled onto some cultural and physical
> changes which set up specific incentives for greater intelligence -
> bipedalism, the use of spears, fire, tools, etc. This brought us up to
> IQ 100. But that was smart enough for these purposes. IQs of 130 or
> 150 wouldn't make someone any better at using these tools.