Although there is evidence of Neolithic and more recent expansions in the Arabian Peninsula, mainly detected by (preHV)I and JIb lineages, the lack of primitive autochthonous M and N sequences, suggests that this area has been more a receptor of human migrations, including historic ones, from Africa, India,It is difficult to assess what this absence of evidence might mean. It's possible the migrants bypassed this region, possibly by boat, or that there was simply never any expansion northward from the coast, into what would have been hostile desert country, or that the descendants of any colonies left behind in this area simply died out over time or were possibly wiped out or assimilated by groups that entered the area much later. In any case, we see little or no evidence of their presence until we reach the South Asiatic peninsula (present day Pakistan and India).
Indonesia and even Australia, than a demographic expansion center along the proposed southern coastal route ("Mitochondrial DNA structure in the Arabian Peninsula," Abu-Amero et al., BMC Evolutionary Biology, 2008).
The differences are cultural as well as genetic, but cultural issues, aside from those centered on language, are rarely discussed in the population genetics literature. Musically there is an enormous gap, especially with vocal music, which is almost exclusively monophonic, with great emphasis placed on solo singing, often of a highly embellished and even virtuosic nature. In strong contrast to the typical voices of Subsaharan Africa, relaxed and open-throated, the Arabic and Persian peoples of this region tend to sing with very tense, narrowly constricted voices.
Whereas most Subsaharan music emphasizes relatively short, simple and unembellished motives, often tossed back and forth among individual singers or in call and response fashion, the music of the Middle East (and North Africa) favors long, elaborately woven melodic lines, often of great intricacy and subtlety, accompanied by instruments playing variations of the same line in a style usually referred to as "heterophony." The contrast with Sub-Saharan Africa isn't universal, and there are in fact certain types of singing based on short phrases tossed back and forth in call and response style -- but almost always with tense voices and in unison, as polyphonic singing is extremely rare if not entirely absent from the entire region. This type of vocalizing is quite different from the open-throated, highly group-oriented, often elaborately interwoven part singing that would probaby have been characteristic of HMC, and seems likely to have developed during a much later period.
Moving on to the next stage of our hypothetical GM journey, and acknowledging that the point I'm about to make will be hotly contested by some, the genetic evidence for HMP and its descendants throughout the entirety of South Asia appears problematic. And the same is true for the cultural evidence. I've already displayed one phylogenetic map for mitochondrial DNA (mtDNA), based on a revised molecular clock that places all the M clades for South Asia at later date than those for Southeast Asia, a very surprising result considering that South Asia represents, in purely geographic terms, an earlier stage along the presumed GM path (see the illustration from the article Correcting for Purifying Selection: An Improved Human Mitochondrial Molecular Clock, as reproduced in Post 262). The molecular clock is undergoing many revisions these days, so any one version of it cannot be regarded as definitive.
But there are other results as well, also reported in recent posts, that present what can only be described as an equivocal picture for this entire region. For example, as reported in Post 264, Cordaux et al., who could not, in 2003, find "any unquestionable genetic signature of the ~60,000 year old migration from Africa to Sahul following the postulated southern route," suggested that "in India the genetic traces of early migrations along the southern route" might have been "erased by the subsequent migrations which shaped the present-day mtDNA gene pool of India."
On the other hand, a more recent study published in 2009, Updating [the] Phylogeny of [the] Mitochondrial DNA Macrohaplogroup M in India, by Adimoolam Chandrasekar et al., concluded that "the basal diversity (37 nodes) and founder ages (57,000–75,000 years) of macrohaplogroup M in India reveals [an] initial settlement of [the] African exodus in India. . . several Indian mtDNA M lineages are deep rooted and [have an] in situ origin." Since the Chandraseka paper doesn't challenge the findings of the Cordaux group, it's hard to know what to make of the above conclusion, or of any of the genetic findings for this very complex region, which must be regarded as provisional until larger population samplings become available.
As I've already argued on this blog (e.g., Posts 259 et seq.), certain cultural evidence is consistent with the more problematic genetic findings, both pointing to a serious gap, to some extent an extension of the gap we found in the Middle East, continuing throughout the length and breadth of South Asia as well. As far as the musical evidence is concerned, stylistically both the "classical" court and religious-oriented music and the more "folk-oriented" village music of both Pakistan and India, together comprising an extraordinarily homogenous style family, can be seen as an extension of the traditions of Middle Eastern music, as described above. I recall a private conversation years ago with a leading authority on Indian music, Harold Powers, who confided in me his conviction that Indian classical music was heavily influenced by Moslem traditions, a theory he dare not publish, as it would have made it impossible for him to continue his research in India.
The situation with the tribal peoples of India (and also many of the lower caste groups, who probably originated as tribals) is more complex, largely because they have not been subject to anywhere near the degree of anthropological or ethnomusicological attention as tribal groups to the East and Southeast. Many are, nevertheless, represented in the Cantometric database, and the picture presented there is of a fairly uniform mix of relatively simple singing styles, characterized in many cases by call and response patterns, and in a few cases polyphonic, but completely lacking any sign of what I've called the "African signature," i.e., hocket and/or interlock, yodel, counterpoint, etc., and no sign of the sort of hocketing instrumental ensembles so commonly found in both Africa and greater Southeast Asia.
There is also some very interesting, though inconclusive, linguistic evidence consistent with the same gap, which might or might not be significant, as well as a possible series of major population bottlenecks produced by the eruption (ca 74,000 ya) of Mount Toba, which could have produced such a gap in both the genetic and cultural picture. I won't go into these questions any further here, since I've already discussed them at length in various earlier posts. We should nevertheless keep all of the above in mind as we attempt to follow the peregrinations of our pioneering Out of Africa migrants along the southern route.
(to be continued . . . )