Of course, Jazz is often defined at a root level as the hybrid of African and European musical styles uniquely growing out of the Afro-American experience. No doubt it's true, but there are lots of other things working here as well. One might argue that I'm perpetuating Euro-centric biases by presenting "European Classical Music" as a line of it's own, and continuing to shove the rest of the world into its own cubbyhole.
Well, it's true that I present the influences this way, but I do so more because I feel that it accurately represents the attitudes of musicians -- not to imply that any musicians were necessarily heinous bigots (some were and some weren't), but that the reasons someone in the Jazz idiom would explore African music are similar to the reasons he or she might explore Indian music, and those reasons are different from the reasons that he or she would explore "European Classical Music". Yell at me if you don't like it, or better yet, propose an alternative!
One might also contest the "division" in the "world music" line on the Styles of Jazz chart into a Latin and African & Indian dichotomy. After all, isn't the African rhythmic influence an indispensible factor in the initial origins of Jazz? And isn't a lot of "latin" music also strongly influenced by African rhythmic contributions? The simple answer is "yes". I'd love to give a more detailed answer, but I have neither the knowledge nor the time to research it. Contributions are welcomed.