Even if we grant your argument that brain volume between species isn’t good proxy for intelligence, It doesn’t immediately hold for comparisons within a specie.
No, but correlations there aren’t large, either, if they exist.
Einstein’s brain reportedly was below average size.
That’s a n = 1 example, but there also is a 50/50 example: man vs women. on average, the brains of males are about 10% larger than those of women (https://en.wikipedia.org/wiki/Neuroscience_of_sex_difference...). That doesn’t show up in intelligence differences (https://en.wikipedia.org/wiki/Sex_differences_in_intelligenc...)
Even only looking at males or females, I don’t think larger (fe)males tend to be more intelligent.
No, but correlations there aren’t large, either, if they exist.
Einstein’s brain reportedly was below average size.
That’s a n = 1 example, but there also is a 50/50 example: man vs women. on average, the brains of males are about 10% larger than those of women (https://en.wikipedia.org/wiki/Neuroscience_of_sex_difference...). That doesn’t show up in intelligence differences (https://en.wikipedia.org/wiki/Sex_differences_in_intelligenc...)
Even only looking at males or females, I don’t think larger (fe)males tend to be more intelligent.