This is thanks to Maju, who in a comment to the previous post, questioned an aspect of the above display that puzzled him: the presence of A3 and A4 in northern South Asia, in the first, second and fourth minimaps. Now A3 and A4 stand for two variants of P/B style, contrapuntal interlock and canonic interlock, found in the Caucasus and Europe, usually in refuge areas associated with mountainous terrain. And the reason I initially placed them in South Asia was because there was genetic evidence linking mtDNA haplogroups U5 and HV (see Oppenheimer, The Real Eve, p. 145) with the origins of early Europeans in what is now Pakistan and western India.
In order to account for the population of Europe by descendants of HMP, we need to find a pathway via which some subgroup would have branched off from the main body moving steadily eastward along the southern route. And it occurred to me that the most natural northward path after the Arabian coast would have been along the Indus River. Lo and behold, if our proto-Europeans had made their way far enough along the Indus valley, they might well have been sufficiently far from the effects of either Toba or the Tsunami I've depicted to have survived with their HMC traditions (including A3 and A4) intact. And that would explain why we find P/B variants A3 and A4 so abundantly in Europe as well as Southeast Asia, Melanesia, etc. Which is why I placed A3 and A4 where I did.
Now the reason I'm bringing this up again is because I just discovered that there is in fact an important pocket of tone language in exactly the same region where I placed A3 and A4, the upper reaches of the Indus, which, according to my hypothesis, could have been an important starting point for a migration of U5 and/or HV into the Caucasus and from there to Europe. And if this group had been insulated from whatever disaster befell it's cousins in Southern Asia, that could explain the survival of tone languages in this region. In fact, tone languages seem to have survived, like P/B, only in regions that would not have been affected by either the Toba explosion or a Tsunami centered south of India.
The linguistic map of tone languages shows only one in this general area, Kalami. In fact the entire region, unlike any other in either Pakistan or India, is rich in tone languages:
It appears to be the case that a majority of the languages of northern Pakistan (Punjab, NWFP, Northern Areas, and Azad Jammu and Kashmir) are tone languages. If we look at the numbers of speakers of these languages, it appears to be the case that a majority of the people of northern Pakistan are speakers of tone languages (Tonal features in languages of northern Pakistan, Joan L.G. Baart, p. 2).Putting all the pieces together, we see a striking correlation between the survival of the musical style I've been calling "P/B," according to the hypothesis illustrated on these maps, and the distribution of tone languages in the Old World -- specifically, in SubSaharan Africa, Southeast Asia, Melanesia -- and the northern reaches of the Indus valley. The distribution is seen most clearly in the second map, labeled "Bottleneck Event," where only the surviving versions of my musical "super-haplogroup," A -- including A3 and A4 in the upper Indus valley -- are shown.