Much of Latin America has a large African population--sometime proportionaly larger than the African population of the USA.African-American music
rap, rock, jazz, blues, ragtime,
The banjo is African.
Latin American blacks also contributed in Latin America. Why the astonishment?
If your consider OUR influence on the music of the USA, it would surprising indeed if countries like Brazil, Cuba, Dminican Republic, Venezuela and other Latin countries didn't show a strong African influence.