I am really interested in this discussion. Unfortunately, it is hard to have the discussion in open and receptive terms. Slavery is a touchy subject.
I do know of a Wolossodon played by the national ballet, often linked to Dansa when they play it. The drummers in the ballet explained to me that originally they are not linked rhtyhms, but that they flow nicely together so they play it as an arrangement.
The differentiation between wolosso and jon that Barbara makes is the same I heard in Mali. Jon allowed themselves to become slaves and were regarded as the lowest element of society. Wolosso were born into it so, through no fault of their own, had become slaves. The only Wolosso rhtyhm I heard played was in Bamako, and when in Maninka villages in southern Mali, I did not find anyone who played it (save a few younger drummers who had been to Bamako and picked it up there).
The Jonfoly I learned was from the Bambara of Markala and was played by the bonkolo ensemble. It is drastically different from the Wolosso rhythm. Much more evident than the difference of the Korojuga played by the djembe ensemble and the korojuga played by the Bambara bonkolo ensemble (which are strikingly similar - even though they have a slightly different structure.) Just the fact they are both played in a 9/8 timing (considering there are few other rhythms in this realm).
Musically, beyond this, I cannot say anything about the rhythms because I encountered them nowhere else. The wolosso we played in Mali on the djembe was essentially the same wolosso I hear being played in the US by various teachers (many of you may have more info on this - I have not played with every teacher out there).
I have to say I am continually amazed when people try to differentiate between American slavery and African slavery. My only question: Do we look at the guy who gave his wife a black eye and a bloody nose any differently than we look at the guy who beat the bejeezus out of his wife? (sorry to use this example but it seems to get the point across for me). I don't think the slaves would have thought of it much differently. (many American slaves returned to their plantations to live out their years after the emancipation). Personally, I find any attempt to explain away or justify slavery to be somewhat insulting to my intelligence (not directed at anyone - just in general). Having seen how the lowest class of people currently live in many villages of Mali and how they are regarded by others, to think it was better for the slaves in the past seems to be somewhat silly. But none of us were there so we will never know the reality of it. I have heard many southern Americans try to downplay the severity of their association to slavery - could the same be happening with the Africans relative to their own enslaving history. Seems to be human nature to diminish the ills of our past.
I never heard the explanation given by Abdoul about the seven levels of disassociation. That is very interesting. As for the statement about "breaking the chains". Never heard that one in Mali before.
The term "slave" is commonly used in the sinakouya - the joking cousins that exists between certain familes, classes or ethnic groups. I never heard the term wolosso used in this context, only jon.
Thanks for your input. You can hear the Bambara bonkolo Jonfoly I speak of at http://www.malikan.web.officelive.com/default.aspx
The song equates the horon - who does not belong in the Jon foly to the sera (a bitter additive to a dish they eat - "toh") being put in the Dege (a sweet millet and cream porridge). The ydo not belong. I was told it was the opportunity for the jon to mock the horon in the only realm where they were freely allowed to speak through song. I witnessed many people from Horon families who were mortified at the thought of dancing the wolosso or jondon. Save the few artists who dance it as a professional pursuit.
I was also told the dances of the wolosso and jon are more risque than other Malian dance styles because the slaves have no shame, so they even may dance naked - when i asked why they have no shame they replied - "because they are slaves - why would they"