Why , after 300 years ( or more) of AMericanization would the "socio-cultural, historical and political backgrounds" have any affect on black American IQs? Why would it after the first generation, or second at a long shot? And why would Polish, Yiddish, Gaelic, German, French, Spanish, Welsh and English speakers ( very few speking "standard English" by today's criteria) produce offspring with similar results after said generations, or less, most having arrived after the slaves. Unless she thinks that "socio-cultural, historical and political backgrounds" have long term genetic effects, which would, in fact, be what the opposition is saying. 
 
(Note: I could secde that discrimination may play a part, but that is not the argument she is making).

They were white skinned, then? And homo sapiens was black skinned in the immediate push from africa?