Some people may be interested in reading this article:

Roots and Routes: The connections between dancehall and rap
By Hannah Appel   
http://www.jahworks.org/music/features/rap_dancehall.html


Here's a longish excerpt of that article:

"There are more similarities than not between dancehall and rap music. From shared musical and social histories going back to pre-Middle Passage Africa through today where rhythms and lyrics transmit at rapid speeds via modems, televisions, and the radio, the interconnectedness of these two musical forms is undeniable. DJs and rappers sample one another's material with reckless creativity, and look to one another for collaboration and inspiration...

Origins
Though many of the links between rap and dancehall are more abstract, like African retentions or similarities in language use, their most fundamental relationship is a perfectly tangible one: Jamaican immigrant Clive Campbell (a.k.a. DJ Kool Herc) brought his knowledge of Jamaica's budding dancehall tradition to the Bronx, and in 1974, he invented the break beat, widely understood to be the founding moment in hip-hop music. This celebrated moment, when hip-hop music (rap) was born out of Jamaican dancehall traditions, could use a little context of its own.

Though we have come to understand dancehall primarily as a contemporary form of Jamaican popular music in which DJs and singers perform and record over pre-recorded rhythms, dancehall as a culture and concept has a much longer history than that. Dancehall is also the space where dances are held and where sound systems and artists performed long before the technological innovations of the dancehall music we hear today. Moreover, like hip-hop, dancehall refers not only to a music and a space, but to a whole culture that encompasses music, language, dance, dress, and world views.

Hip-hop and Dancehall's Musical Similarities
In what other ways are dancehall and rap music related? For the sake of simplicity, let's divide these connections into two broad categories: musical links and socio-cultural links. Of course this is a gross over-simplification and it is impossible to truly separate music from the culture that generates it, but for purposes of introduction, we'll look at the formal musical traits that rap and dancehall share.

Certainly the innovations of Kool Herc provide the defining shared musical connection between rap and dancehall, but we have to look much farther back than Clive Campbell's immigration to see how these musical styles came to share so many of their formative elements. Rap and dancehall share two fundamental and definitively African elements: orality and rhythm, that date back to sub-Saharan Africa far before the forced migrations of slavery.

With their lyrical focus and ability to manipulate language for speed, affect, content, etc., rappers and DJs are the contemporary incarnations in a long line of orators, following the West African griot figure, or one who would spread news and stories in the community. Many writers and thinkers have also related the orality of dancehall and rap to the West African concept of "nommo," which understands the power of the word to be the power of life itself. To speak something or to "speak on" something is to generate it, or make it come into being. (See the work of Henry Louis Gates or Geneva Smitherman.)

The second definitively African element that both rap and dancehall share is their mutual reliance on rhythm. While the foundation of music that comes out of classical European traditions is with melody, music informed by classical African traditions relies almost solely on rhythmic creativity and layering. Rap and dancehall both share this reliance on rhythm, offering their lyrics over heavily laden bass tracks full of drum machine sound effects, handclaps, and even traditionally melodic instruments like the guitar or the horn used as rhythmic accompaniment. (Think of the "one drop" in reggae or the horn section in often sampled funk riffs.)

While it's important to acknowledge the African musical roots of these traditions, those roots are only one part of a much larger picture. That larger picture is a much more modern view in which rap and dancehall both rely extensively on newer technologies (microphones, turntables, amplification, keyboards, computers, etc.) and the extraction and recycling of old musical material into something new and exciting, a process known in hip-hop as sampling (and a habit so ingrained in dancehall it doesn't have a name.)

These changes took place in urban points in the African Diaspora [in]Kingston, New York, etc. The technological innovations of the second half of the twentieth century are really the musical heart of rap and dancehall. These technological advances include allowing the sampling of recorded material, and transporting an entire sound system not only across countries but also across oceans. Certainly the earlier innovations, like record players and microphones, were central to the musical forms, but it is the more recent developments in information technology that are speeding up the relationship between rap and dancehall music and the cultures out of which they come...

The music industries in both Jamaica and the U.S. are deeply affected by this informal economy in all kinds of ways, from bootlegs, to artists' individual connections to organized crime. (If you don't believe me, just listen closely to the musicÉ Which brings us to another shared lyrical tendency: boasting and posing as a "bad man" when you may or may not have done all the things you say you have. Although suffice it to say, many of the connections and claims are true.)

This has been a bare and decidedly incomplete introduction to some of the relationships and connections between rap and dancehall music and culture. More exploration can be done on topics like language, or the relationship of music to money and the market.

For examples of musical cross-breeding, it is fair to say that any dancehall album you listen to will have clear hip-hop influences, if not several guest rappers. Hip-hop albums similarly co-opt Jamaican traditions and artists for cameos. Beenie Man's recent spate of appearances with everyone from Lil' Kim (Straight from Yard) to Janet Jackson is one example, as is the Wu Tang Clan on the recent Capleton single "Judgement Morning."

eend of article

Here's the information presented on that website about the author of the article:

Hannah Appel is a San Francisco native who has spent the last two years in Kingston, Jamaica on a Fulbright grant, studying language and music. She has a B.A. in anthropology from Yale University, with a Caribbean studies focus. She makes a mean red peas soup and can "log on" and "zip it up" with the best of them.


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In my opinion, this entire well written article is well worth the read.