And Dave: I agree that Peter early on included African forms in his music from the late 70’s through 80’s, albeit perhaps from a more progressive angle, but in so doing, he promoted awareness of rhythm and modern melodic content, influencing many musiciansingersongwriters, Paul included, to learn, share and collaborate.
Remember, there was Joni before Peter (Jungle Line), along with the Chambers Brothers (Time Has Come Today) and Grand Funk (Stop Looking Back). Others may identify additional examples.