How are Black people so genetically diverse?

African Americans, Mbuti Pygmies, Fulanis, Jamaicans, Batwa Pygmies, Masais, Igbos, Khoi Sans, Baka Pygmies, Zulus, Afro-Dominicans, Hutus, Sandhwes, Hausas, Akans, Gurmas, Dinkas, Twa Pygmies, Gyele Pygmies, etc.
How are Black people so genetically diverse?
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