IQ's are biased and mostly insignificantly when comparing to any culture other than your own.
Things that we are great at may be entirely different from other cultures. There are cultures in South America where children can identify over 2000 different plants and can estimate the distance or height of a tree with in yards/feet depending on the item.
There are cultures in which the people are poor and uneducated but still grow up learning 3 - 5 languages.
If you want to go into differences in thought processes between one group and another, I think it's far more interesting to look at tests that show brain functioning between different groups. This has been going on a lot amongst things like comparing brain function between liberals and convervatives. So interesting to see what parts of the brain are being utilized and how that changes reaction.