The construction of the test influences the IQ score. I imagine that if you developed an IQ test for living effectively in Equatorial Guinea, the folks in Hong Kong would do much worse than the folks in EG.
The Bushman tribes live in a very difficult environment. I imagine even a high IQ Westerner would have a hard time surviving there for more than a few weeks or months. What would the average IQ be if ten Bushman newborns were raised in a college professor’s household. Here is an interesting link about testing intelligence across cultures:
http://www.apa.org/monitor/feb03/intelligence.aspx
As a practical example, my son was dyslexic and a high school dropout. However I reassured him he could do well because he had highly developed social intelligence, and could always hire a secretary. He is now in his 40’s, happily married with children, and running his own business contracting construction jobs with several employees.