Most of us are mixed, though we may not look it. Someone who is 12.5% European and 87.5% African won't necessarily look much like the former. Also, remember that countries like Cuba, the Dominican Republic, and Puerto Rico are Caribbean countries, and people solely of African descent make up a small minority in them. My country, Jamaica, is more visibly black, but I'd still say about half of us are mixed, if not more. There are no good studies on our genetic makeup though. But the reason why the English-speaking islands tend to appear less diverse--Trinidad & Tobago and Guyana (yes, we count Guyana) are exceptions, with more people of Indian descent than of African descent-- is that the proportion of enslaved Africans brought over was greater in proportion to European who settled. That, in addition to the ancestors of most Afro-Caribbean people came to the islands near the end of the slave trade, even though it had been in effect for centuries prior. But before the slave trade was abolished, it was cheaper to work slaves to death within 10 years and buy new ones from Africa than it was to allow them to breed and have to feed all those children. Therefore much of the African population still hasn't been here long enough to mix with the rest of us. The Maroons, a visibly black population, however, have been in Jamaica longer than other black lineages and genetic studies on them have revealed that they are also mixed, most interestingly, with Taino.