Listening to, for an example, Jamaican mento, a type early folk music from Jamaica that predates ska and reggae, I think there's a clear retention of this sort of music's African origins, in both it's instrumentation and direct rhythm. In contrast, stuff like early, pre-war blues and spirituals of the African Americans do not really seem to retain much of their African roots, if any at all. Why is this? At what approximate point would African American music become more westernized than African? Why is black Jamaican music more retentious of it's African roots? What differences between the conditions of black Jamaicans and African Americans (Both free and enslaved) caused this contrast?
Edit: Bonus question - Why do black Jamaicans seem more African than African Americans in general? This is probably too broad a question in addition to the other stuff, but I feel like it will most likely tie in somewhere along the line anwyays.
It's not quite an answer to your question, but I have a previous answer on the origins of and influences on, broadly speaking, Jamaican R&B and a previous answer on the African influence on black American music forms. Broadly speaking, I don't think Jamaican music is particularly more influenced by African music than black American music, but that the enormous influence of black American music on pop culture in general over the last century means that a lot of the sounds of that music now sound 'normal' where the equivalent amount of African influence in Jamaican music like mento now sounds 'exotic'.