im generally siding with the guy posing arguments that IQ measurements by race are generally full of shit. (a brain is a brain imo)
however, even though the immigrants may have the capability of assimilating to "high IQ", you cant teach an old dog new tricks.
they arent going to be as motivated to swap cultures on a dime, and that lack of motivation will reflect itsself to some degree in IQ measurements.
Has more to do with where certain races happen to fall culture wise then actual natural genetics.
But seems some have just bred them selves to low intelligence by choices of cousin fucking and maintaining close caste systems.