Thursday, July 30, 2009

177. Music and Cultural Evolution -- Part 4

I deliberately chose the Ik as an example because they represent an extreme case, and the forces driving change are often easier to grasp in their most extreme, and thus most simplified, form. As I wrote in a comment to my previous post,
Of course, the Ik represent an extreme case, and it's not difficult to imagine such a disaster leading to a culture dying out completely. But what if it doesn't die out? What if there are survivors who manage to begin anew at some point, what will they be teaching their children? What aspects of their old culture are likely to survive, what are likely to be lost and what new elements are likely to be introduced?
As far as population genetics is concerned, there is one thing we can say for sure. When a population has been drastically reduced in size, for whatever reason, its genetic diversity will also be drastically reduced, in a type of genetic drift known as a population bottleneck:
Population bottlenecks occur when a population’s size is reduced for at least one generation. Because genetic drift acts more quickly to reduce genetic variation in small populations, undergoing a bottleneck can reduce a population’s genetic variation by a lot, even if the bottleneck doesn’t last for very many generations. . .
Population bottlenecks lead to founder effects:
A founder effect occurs when a new colony is started by a few members of the original population. This small population size means that the colony may have:
  • reduced genetic variation from the original population.
  • a non-random sample of the genes in the original population
It's not difficult to see how, in a society enduring as much extreme stress as the Ik (and here I am speaking hypothetically regarding the possibility of a parallel situation in the distant past), only a relatively few individuals might manage to survive. As far as the geneticists are concerned, this drastic reduction in size would already, in itself, produce both a population bottleneck and founder effect. But that wouldn't be the end of it, because we are dealing here with a human population, maintaining certain social and cultural traditions that will also, inevitably, be affected. In other words, we can conclude that population bottlenecks will lead to socio-cultural bottlenecks, which will, in turn, produce socio-cultural founder effects.

It's impossible to predict which aspects of the old culture will endure and which will fall by the wayside, as this will depend on the individual characteristics and preference of the survivors. If they are anything like the Ik survivors, however, we can make some predictions with a reasonable degree of confidence. For one thing, if their old, pre-bottleneck culture were as communal as that of most African societies, many if not all these communal values might well be lost. If, like the Pygmies and Bushmen, and so many other hunter-gatherer groups, they were in the habit of sharing all food and other goods equally among themselves, with no thought of repayment, one might expect a very different sort of "economic" code among the bottleneck survivors. If they had been non-violent and cooperative in the past, one might expect that the survivors would not only be more prone to violence and less cooperative, but that they would also place a social value on both violence and self-interest, a value that might well be reflected in a new set of myths, legends and other traditions to be passed on to future generations.

Musically, one could predict the loss of certain elements that might have been a part of the older tradition. Certainly if they had been in the habit of singing in P/B style, or something resembling it, there would be a considerable loss, simply due to the breakdown of communal life. We might well expect far more emphasis on solo singing, with unison being more likely than polyphony in cases where group singing might be revived. As I see it, and I think this hypothesis can be supported from what we already know about the musical "evolution" of many groups, Joseph Jordania's observation regarding polyphonic singing makes a great deal of sense: once the habit of singing spontaneously in harmony (i.e., polyphonically) is lost, it will never be regained -- not at least in the most traditional societies.

One more thing to keep in mind. Regardless of the cause of the initial population bottleneck, once the new set of traditions is established by the surviving founder group, there us good reason to believe that the new traditions will tend to persist unchanged, even after the conditions that led to the bottleneck improve. Seen from this perspective, therefore, it appears as though culture, contrary to the assumptions of functionalism, is not determined so much by the environment as by a very fundamental principle, far too neglected in our time, the sheer inertial force of tradition. This is of course a hypothesis, not a rule, as there is still much to be learned about cultural evolution. It is, however, a testable hypothesis -- in the testing of which the musical evidence is now playing a crucial role.

Monday, July 27, 2009

176. Music & Cultural Evolution -- part 3

I've been thinking lately of two very different books, both by the same remarkable author, Colin Turnbull. In his now classic study of the Mbuti Pygmies, The Forest People, Turnbull has a lot to say about the music of the people he's studying, in fact he can hardly contain his enthusiasm. However, in a lesser known book, The Mountain People, he has hardly anything to say about music at all.

For Turnbull, the music of the Mbuti cannot be separated from their life in the forest and their culture generally, and indeed there is much in P/B that reflects their lifestyle to a remarkable degree. Music among the Mbuti is an expression of a society at once highly communal, yet at the same time remarkably free of regimentation in any form; highly organized, yet without formally determined leaders; an egalitarian society in which everyone is expected to share equally with everyone else, with no expectation of reciprocity; where women have an equal say to men; and warfare is all but unheard of. The most fundamental values of this society are mirrored in a musical style based on the tightly knit interweaving of equal parts, usually combining both male and female voices, each improvising in his or her own way, freely entering or dropping out at will. Everyone is expected to contribute his or her own unique part, in such a way as to produce a perfectly blended resultant of maximal harmoniousness and resonance.

The picture painted in The Mountain People is radically different. When Turnbull encountered them, the so-called Ik (an alias -- their actual tribal name is not provided) had been displaced from their traditional lands to make room for a nature preserve, victims of "fatuous rules that were designed to preserve animals while humans, in consequence, starved and died" (p. 93). As a result, theirs was a society radically altered from what it had been only shortly before. Turnbull has been criticized, in fact, for presenting a distorted picture of a people whose traditional culture had been very different from the picture he presented in his book. But it wasn't Turnbull's style to dig too deeply into the past. He was more interested in assessing what was going on around him in real time, and how things were changing, which they certainly were.

Ik society was, at that time, undergoing severe stress, and the stress had very definite and very dire effects on a people who had become increasingly desperate with hunger and other forms of deprivation, to the point that their cultural values were disappearing into a mode of existence based, as one might expect, on the philosophy of "every man for himself" aka "dog eat dog." Turnbull very honestly makes no secret of his disgust when confronted with many acts of cruelty and neglect, while at the same time expressing his sympathy for people with no other viable options.

While the Ik may be seen as victims of a characteristically modern, "post-colonial" situation, the radical changes recorded by Turnbull can give us an insight into what could have happened at certain times in the past, when a particular population is suddenly placed under tremendous stress to the point that the most basic cultural norms begin to break down. Of special significance for us is the relative scarcity of musical references in the book. Whenever singing is mentioned, it's almost always solo singing, not surprising in an atmosphere where social cohesion is breaking down and "every man for himself" has become the norm. The only group singing noted by Turnbull among the Ik is the singing of Christian hymns, and that takes place only when a group is expecting a consignment of food from some missionaries (who never show up). He has nothing to say about what their music might have been like in the past, but if the Ik were a typical African tribe, we can be almost 100% sure that group singing would have been common. In the context described in the book, however, occasions for group singing, either for pleasure or for traditional ritual purposes, no longer exist.

Is there anything we can learn from the above contrast, between a (then) thriving band of forest Pygmies, for whom singing is an everday expression of joy and solidarity and the starving remnant of a once viable group of hunter-gatherers turned farmers, who hardly ever sing at all? I think there is, because the sort of radical, sudden and disastrous change we see among the Mountain People might well give us some insights into at least one way in which culture may have changed in the past -- though "evolution" might not be exactly the right word for it.

(to be continued . . . )

I may not have time to be posting much if at all in the next week or so, but I'll be back soon, I promise . . .

Saturday, July 25, 2009

175. Music & Cultural Evolution -- part 2

It might seem only logical to assume that any particular aspect of culture will gradually change over time -- and this sort of incremental change is usually what we understand by the term "evolution." Language is an excellent example. Take a particular population speaking a particular language, split that population into two groups, send one group off to a different part of the world and inevitably, given enough time, you'll notice that the two groups are no longer speaking exactly the same language anymore. Pronunciations begin to vary, new words are introduced, others forgotten, certain inflections might become more pronounced in one group, less so in the other, etc. After several hundred years, the two populations may no longer be able to understand one another at all, though the roots of their languages are the same. There seem to be certain universal laws built in to language that inevitably lead to change. And there's no reason to believe the same laws wouldn't apply to all aspects of culture, including music. We could call this phenomenon "cultural drift."

If cultural drift applied to music, however, then how can we explain the extraordinary survival of a single tradition among so many groups of Pygmies and Bushmen over tens of thousands of years? And if they really thought much about it, the ethnomusicologists would have realized a long time ago that there are all sorts of traditions which have to be survivals of extremely old practices, judging from the wide distribution of certain closely related styles (or, if you prefer, musical "languages"), e.g., the Anglo-European Ballad, the Eurasian epic, the Moslem-Hindu maqam-raga complex, north Amerindian unison/iterative/one-beat, Bantu African call and response plus drum ensemble, etc. While any given melody or composition is likely to change over time or vanish entirely due to cultural drift, the musical language itself (or, if you prefer, "style") will persist. Until something happens to change it.

Explaining why musical styles persist and also why they change is (or should be) one of the great challenges of Ethnomusicology -- but not only Ethnomusicology, because this is a question that concerns (or should concern) Anthropologists, Archaeologists, Historians and anyone else with a serious interest in culture and cultural evolution.

If, thanks to all the many arguments I've already presented, we can regard P/B as a kind of "baseline" (a term Alan Lomax once used to describe the Pygmies and their music), then this tradition would probably be the best place to start. And to my mind the most fundamental questions to ask are: 1. how did this highly distinctive, complexly interactive musical tradition arise among our earliest ancestors in the first place? and 2. what happened, among the various lineages that ultimately diverged from the ancestral group, to change it?

To some extent, I've already considered both questions, speculating first on the origins of P/B beginning with post no. 21, "Music" in the Year Zero. What I noticed that seemed important was the resemblance between certain types of highly interactive primate vocalization, specifically what is called "duetting" and "chorusing," and the practice, so fundamental to P/B, of closely interlocking vocal (or instrumental) parts, or "hocket." Combine duetting and chorusing with the tendency of many primates to produce "hooting" sounds not unlike yodel, and we see, if nothing else, an opportunity for further research into some very intriguing possibilities. Unfortunately, there's not much more to be done in this area until more research has been done on primate vocalization.

As for question no. 2, I've done some speculating on that one as well, beginning with posts no. 46 and 47, which contains the following rumination:
. . . when and why did so many of the Bantu groups abandon P/B style for the type of vocal interaction now most common among them today, what is usually referred to as "call and response"? I don't think the change in musical style could have coincided with the separation from the "founding" group, because there are still certain Bantu tribes that do in fact still vocalize in P/B style -- some with yodelling as well (see map). It seems likely, therefore, that there must have been a split among the Bantu at some point after their separation from the founding group.

Why am I talking in terms of a "split," which implies a rather sudden occurrence, rather than a more gradual "evolutionary" process? Here, it seems to me, we come across a problem of fundamental importance to an understanding of history, both musical and otherwise. Let's assume that, after the initial separation from the "founder" group, the Bantus remained intact as a single unit over a very long time, and that during this time all sorts of gradual changes could have occurred, including musical ones, leading step by step to the replacement of P/B by call-and-response. Then, after the latter style had been established, the original Bantu population began to break up into the smaller units we are familiar with today, the groups that eventually spread throughout Africa during the "Bantu expansion."

This might seem reasonable until we ask ourselves 1. why the Pygmy and Bushmen groups did not also gradually evolve away from P/B style? 2. why Bantu vocal music ceased to evolve after the call-and-response style had been established, prior to the Bantu expansion? Everything we know about the music of traditional peoples tells us that they have a very strong tendency to maintain their traditions intact, from one generation to the next; and since the generations overlap, in some cases at intervals as short as 15 years or less, there is little opportunity for any sort of fundamental change to become established.

It seems to me, therefore, that there must have been a split at some point, something rather sudden, that divided the Bantu into two groups, those that maintained the original P/B style and those that for some reason were not able to maintain it. This is in line with an approach to evolution generally that's come into prominence in recent years, known as "punctuated equilibrium," very close in theory to the notion being promoted nowadays among the geneticists, the "population bottleneck." What's implied is that some small part of an originating population becomes isolated from the main group, possibly as a result of a dispute, or warfare, or some natural catastrophe, etc. . . .

Thus, the call-and-response polyphony now so common among so many Bantu groups, could have had its origin in some relatively sudden event now lost to history, that produced a new type of population with a somewhat different cultural outlook from its predecessor. The new outlook could also have led to new types of complexity along different lines, such as the proliferation of the many different instrumental traditions now found among so many Bantu groups, but not Pygmies and Bushmen.
Forgive me for quoting myself at such length, but what I wrote back in 2007 still makes a great deal of sense to me. Unfortunately it's a theory in direct contradiction with what most people consider "evolution" to mean, since that term usually implies both gradual change and, despite all the many objections of late in the name of political correctness, some sort of progress, either from the "primitive" to the "sophisticated" or, somewhat more "correctly," from the "simple" to the "complex." What I tend to see, on the other hand, at least as far as the earliest stages of musical "evolution" are concerned, are processes characterized by both sudden change -- and loss. And, what is of more general interest -- and where I'm going with all this (in case you've been wondering) -- is a consideration of similar models of sudden change and loss in the early evolution of culture itself -- or at least certain aspects of it. In other words what I'd like to explore is the way musical evolution, coupled with what we are now learning from the genetic research, might provide us with clues to the understanding of certain types of cultural process generally.

(to be continued . . . )

Friday, July 24, 2009

174. Music & Cultural Evolution

If the common ancestors of the Pygmies and the Bushmen are indeed, as the genetic evidence so strongly suggests, the common ancestors of all homo sapiens who have survived to the present day; and if we indeed, as I have been arguing so vociferously, have a very good idea of what their music sounded like (as surprising as such a claim might seem); then their musical style, which I've been calling P/B (for Pygmy/Bushmen), can, as with their genes, be considered in some sense ancestral to at least some -- if not all -- of the many different modes of music making we find in the world today. Which is a basic point of my essay, Echoes of Our Forgotten Ancestors. More recently, after careful analysis of specific examples of this "ancestral" style, I've become increasingly aware of just how special it is; that it can in some sense be regarded as a "comprehensive" style, meaning that it already contains within it features that could be regarded as prototypical for a great many other styles that we might want to call its "descendents." Especially interesting is the way in which certain practices normally considered completely different from one another are conflated in P/B (see previous post).

We might naturally assume that certain types of African music would come particularly close in style to the ancestral type and that, as far as I've been able to determine, does seem to be the case -- though certainly not in all cases. This is a topic I've already covered, at least to some extent, earlier in this blog; first where I presented a map indicating the name and location of various African groups that vocalize using interlock and, in some cases, also yodel, the two most distinctive features of P/B; and second, in the following post, where I focus on "hocket," a type of closely interlocked vocalizing (and instrumental performance as well) especially characteristic of Pygmy and Bushmen music, but also of great importance in many parts of Africa.

What is of special interest with regard to the status of the Pygmies and Bushmen in this respect, is the way in which almost all instances of P/B, or P/B related music, in Africa or, indeed, elsewhere, represent the style in a more or less "watered down" fashion. And this "stylistic dilution" can take two forms: musical and cultural. Musically what we often find are styles in which interweaving parts are present, but in a relatively simpler form, sometimes combined with the typically "Bantu" call and response; or instances in which typical P/B features, such as interlock, occur only sporadically, rather than continuously. While most P/B performances are additive, i.e., open-ended with respect to the number of independent voices that can join in, similar performances among non-P/B groups often involve a restricted, pre-determined number of parts. Among many so-called "Bantu" groups, P/B style hocket-interlock is characteristic of instrumental performances, such as drumming, xylophone or flute playing, etc. but not vocalizing. And in the vast majority of cases where we find P/B-style interlocked vocalizing, it is not accompanied by yodeling, as it would be among almost all Pygmy and Bushmen groups (with one especially interesting exception: the Bedzan).

Culturally, among non-Pygmy-Bushmen groups, what we find is a tendency to vocalize in this style (when done at all) only on certain occasions, in contrast to Pygmy or Bushmen practice where the style is a daily feature of ordinary life. In certain cases vocalizing in this manner is restricted to certain rituals only, or limited to the performance of professionals or semi-professionals or other specialists, whereas among the Pygmies and Bushmen everyone, including small children, can join in. Among the Dorze of Ethiopia, one of the few such groups that both interlock and yodel, in a manner strikingly similar to Pygmies or Bushmen, P/B is only one genre of many, restricted to certain work situations or festivals. Among certain farming groups in the Mandara Mountains of Cameroon, vocalizing of this type is associated with pipe ensembles that perform only at certain points in the growing cycle. Similarly, among the Wagogo of Tanzania, interlocking polyphony is restricted to certain times of year, also coordinated with the growing cycle. Finally, we must also note the influence of P/B on the simpler "call and response" style of so many "mainstream" Bantu peoples, where the leader's part can often interlock quite closely with that of the chorus, to the extent that, as with hocket, a phrase in one part is completed by the other.

Why is this? How does it come about that among certain groups a musical style remains essentially intact over tens of thousands of years, while among others it morphs into something very similar but nevertheless different, and maybe also becomes associated with certain cultural functions only, such as certain types of work song or certain types of ritual? And why is it that in other cases, it either gradually evolves or suddenly changes into something quite different, as for example, call and response rather than continual interweaving of parts? And why are certain call and response traditions, in Africa and elsewhere, restricted to unison, while others remain polyphonic? And why do we find in certain parts of the world, music that is radically different from either P/B or call and response or anything resembling (apparently) any form of African music?

(to be continued . . . )

Monday, July 20, 2009

173. The Pygmy/Bushmen Nexus -- Part 12 -- A Comprehensive Musical System

While much in my most recent essay is based on materials first presented in this blog, under the heading Music of the Great Tradition (see especially posts 118 through 146), one very fundamental idea, which only occurred to me after I'd gone to the trouble of systematically listing all the many Pygmy-Bushmen commonalities, is new. The list is very long and I won't bother to reproduce it here, since anyone interested can look it up in the paper itself (Some Notable Features of Pygmy and Bushmen Polyphonic Practice, with Special Reference to Survivals of Traditional Vocal Polyphony in Europe, pp. 3-4). What is new is my realization that this list reveals something truly remarkable and possibly unique in all of music:
Indeed, as careful study of the rich and unusually long list of distinctive features reveals, both the Pygmy and Bushmen traditions seem to have already encapsulated within them features characteristic of many different musical traditions in many parts of the world, as though P/B had served as some kind of prototype. The notion that a single style of great antiquity could serve as a prototype for so many different musical practices now prevalent throughout the world is speculative, to say the least, yet consistent with evidence suggesting that the original “Out of Africa” migrants could have been perpetuating the same tradition . . . In this sense, P/B could be considered as, in some sense, a comprehensive musical system. Is this simply an interesting observation? Or could it have more serious consequences for our understanding of music generally (pp. 4-5)?
What impressed me so deeply, in addition to all the many other things about this style that impressed me, was the fact that I could not think of a single other musical practice in which so many different characteristics to be found elsewhere in the world came together in performances of such apparent complexity and intricacy which, at the same time, were produced so effortlessly and with so little self-consciousness. Many musical features usually thought to be completely different or even opposite from one another are actually conflated in this tradition. While P/B is fundamentally polyphonic, certain passages can take the form of a kind of tightly coordinated heterophony. Moreover, extended heterophonic passages of this kind can sometimes come quite close, in their effect, to simple unison. The intricate back and forth interplay of hocketed parts can't always be distinguished from antiphony, the basis of mainstream Bantu "call and response." As Susanne Fürniss has so effectively demonstrated, solo songs can be derived from an amalgam of polyphonic parts and, as Emmanuelle Olivier has so clearly shown, multi-part counterpoints can be derived from single melodies.

While P/B performances can sound to the uninitiated like unorganized streams of continuous group improvisation, careful study has revealed that they are, in fact, based on controlling, continually repeated rhythmic cycles and melodic configurations, either expressed or more often implied, which provide a harmonic, rhythmic and motivic reference for everything else we hear -- much as in a jazz performance, where the controlling melodic/harmonic basis can go completely unheard. Not only jazz, however, but a great variety of otherwise very different musical structures from many different musical traditions are also based on regularly recurring rhythmic/metric cycles and repeated melodic phrases or groups of phrases, often set to different words with each repetition, but in every case based on a musical principle already found in a tradition that can be traced back to Africa tens of thousands of years ago. While the existence of regularly repeating meters and so-called "strophic" forms can all too easily be taken for granted as musical givens, it should be clear by now that nothing to do with music can be taken for granted, that everything we now hear had its origin at some point in the past.
(to be continued . . . )

172. Articles Now Available for Download

I'm pleased to announce that Amand Aglaster, director of VWB-Verlag, publisher of the journal The World of Music, has given permission for me to make my essay, Echoes of Our Forgotten Ancestors, freely available for download via this blog. Just click on the title and select "Save Page As . . ." If you'd like to order a beautifully printed and bound hard copy of the entire issue, you may do so from the following website:

A preprint version of my most recent paper, Some Notable Features of Pygmy and Bushmen Polyphonic Practice, with Special Reference to Survivals of Traditional Vocal Polyphony in Europe, is now available for download as well, by permission of the editors of the Proceedings of the Fourth Annual Symposium on Polyphonic Music, held last year in the Republic of Georgia, where it is scheduled for publication next year.

Finally, I'll remind you that my essay New Perspectives on the Kalahari Debate, published a couple years ago in the anthropology journal, Before Farming, can also be downloaded via the link provided above. Thanks again to the publisher WAS Press, for permission to freely share this work.

Saturday, July 18, 2009

171. The Pygmy/Bushmen Nexus -- Part 11 -- African Offshoots

(. . . continued from previous post.)
While P/B style in its most fully developed and complete form is almost exclusively limited to certain African Pygmy and Bushmen hunter-gatherers, musical practices employing certain characteristic features of P/B are not uncommon among other indigenous peoples, in various corners of the world, with very different histories, traditions and modes of subsistence. In my paper on the Kalahari debate, I present statistical tables drawn from the Cantometrics database, to illustrate the manner in which two of the most distinctive characteristics of P/B, interlocking parts and yodel, are distributed, both worldwide and in Africa. For now, I'd like to concentrate on the African picture, to give us a better sense of how this style may have evolved on that continent during the earliest phase of its development and diffusion. To that end, let's take a look at Table 3 from the paper, which presents an overview of the distribution of interlock and yodel in the Cantometric sample from SubSaharan Africa, followed by some excerpts from my discussion of this table:

Sample Size

No. Interlock

% Interlock

No. Yodel

% Yodel

Pygmies (Aka, Baka, Bedzan, Binga, Mbuti)






Twa Pygmies






Ju’hoansi Bushmen (including “Kung”)






“Khwe” Bushmen






Mikea (Madagascar)






Wayto (NW Ethiopia)






All other hunter-gatherers (El Molo, Hadza, Sandawe)






All other groups in Sub-Saharan African






All other groups coded as interlocked






The first seven rows represent hunter-gatherers exclusively. The last two enable us to assess the degree to which interlocked vocalising and yodel is found among all other sub-Saharan groups sampled. As can be seen in row eight, from a total of 873 performances representing these groups, only 88, or 10%, employ interlock. Row nine represents a subset of the above, all songs from all such groups with at least one instance of interlock coded for each. While the great majority of performances in our Pygmy and Bushmen samples are interlocked, this type of vocal interaction is found only 34% of the time among those farmers and/or pastoralists where any instances of
interlock have been coded. Interestingly, most such groups are located in areas adjacent to or in the vicinity of, Pygmy or Bushmen populations. . .
From rows eight and nine we see that yodel is found in only 5% of our non-hunter/gatherer groups and not much more, 9%, among all such groups using interlock. Clearly, the use of both interlock and yodel is characteristic of most Pygmy and Bushmen vocalising, yet rare in either Africa or anywhere else (p. 9).
I'd like, at this point, to add another quotation, from my most recent, as yet unpublished, paper, in which I speculate further on the very interesting distribution of certain characteristic P/B traits in Africa. Please forgive these extensive quotes, but they contain much that is germane to the present discussion:
Certain aspects of P/B link the style quite closely to many types of vocal and instrumental practice in Africa, from simple call and response antiphony, which often resembles hocketed interplay, to polyrhythmic drumming, interlocking instrumental ensembles, etc. The many hocketed vocal, pipe, panpipe, trumpet and horn ensembles so commonly found in Africa may well have originated as an early derivation from P/B hocket-interlock. Interestingly, the musical traditions in Africa that are closest to P/B, in their use of interlock, hocket, stimmtauch, continuous flow, ostinato, nonsense vocables and even, in certain cases, yodel, tend to be found either among groups that have traditionally interacted closely with Pygmies or Bushmen, or groups to be found, as the Pygmies and Bushmen are now found, in relatively isolated “refuge” areas. For instance a well-known pocket of P/B style hocketed vocal and pipe-based contrapuntal polyphony can be found among several groups living in remote mountain regions of southwest Ethiopia. Another such pocket can be found in the Mandara Mountains of Cameroon, a well-known refuge area, surrounded by very different lowland groups that sing and play in markedly different styles. Another such group, the Bamoun, live in a high plateau region of Cameroon, with an elevation of close to 4,000 feet. Still another group, the Anaguta, now live in the Jos Plateau region of Nigeria, also recognized as a refuge area ("Some Notable Features of Pygmy and Bushmen Polyphonic Practice, with Special Reference to Survivals of Traditional Vocal Polyphony in Europe," p. 5).
What I am suggesting in the above can best be summarized by yet another quote (again, please forgive me, but this sort of recycling saves me considerable time and effort), this time from the abstract to a grant proposal (unsuccessful) I recently submitted to the Wenner Gren Foundation:
Informal research conducted so far suggests that variants of [P/B] style tend also to be found among food producers that have traditionally interacted closely with Pygmies, or among marginalized, relatively isolated, culturally conservative groups now living in out-of-the-way refuge areas scattered throughout the continent. Such a distribution pattern, if confirmed, would imply that all such traditions could indeed be survivals of an archaic practice, predating the Bantu expansion, possibly dating to the Paleolithic. I intend to test this hypothesis by more systematically mapping the distribution of “Pygmy/Bushmen” style vocal and instrumental music throughout Africa, as fully as current information sources permit.
I'll add one more (long) quotation, this time from the project description itself, which should give you an idea of what's been on my mind regarding the effort to understand the history of P/B, its variants, and their distribution among so many different African groups. As my proposal should make clear, there is still much that remains uncertain and merits additional research.
The proposed project will focus on certain musical traditions, both vocal and instrumental, closely related stylistically and structurally to P/B, though often somewhat simplified and less spontaneous, that can be found among certain groups of “Bantu” farmers and/or herders in various parts of Sub-Saharan Africa. Interestingly, such practices are often limited to certain times of year, or certain types of situation or ritual, whereas singing in this manner is an everyday part of ordinary life for most Pygmies and Bushmen. So far, P/B variants of this sort have been found in 1. groups that have traditionally interacted closely with Pygmies (e.g., Mamvu, Lese, Bira, Budu, Ngundi) or Bushmen (e.g., Himba, Pondo, Lozi), or 2. marginalized, relatively isolated, culturally conservative groups now living in out-of-the-way refuge areas scattered throughout the continent -- e.g., the highlands of southwest Ethiopia (e.g., Dorze, Ari), the Mandara mountains of Cameroon (e.g., Ouldémé, Mofou), the Jos Plateau region of Nigeria (Anaguta), etc.

Are such distribution patterns the coincidental result of an incomplete survey? Or do they point to isolated survivals of an archaic, once ubiquitous, cultural practice, predating the Bantu expansion, possibly dating all the way back to the Paleolithic? If it can be determined with a reliable degree of statistical significance that P/B-related musical traditions are found exclusively, or almost so, among such groups, then the latter hypothesis would receive considerable support. Alternatively, a comprehensive survey might tend to support the theory offered for the distribution of hocketing wind ensembles by linguist/ethnomusicologist Roger Blench, who suggested that such ensembles could originally have been “part of the cultural repertoire of Nilo-Saharan speakers as they spread westwards across the Sudan in the Pleistocene” (Blench 2002). If no clear correlation of any sort emerges, it would be necessary to consider the possibility that stylistic practices and behavior patterns similar to P/B could have emerged independently among various “Bantu” groups, due to similarities in cognitive development, environmental influences, and/or historical events currently unknown to us. It is hypotheses such as these that I intend to more fully explore by systematically mapping the distribution of P/B style vocal and instrumental music throughout Africa, as fully as current information sources permit.
(to be continued . . . )

Friday, July 17, 2009

170. The Pygmy/Bushmen Nexus -- Part 10 -- African Offshoots

My friend Maju makes an interesting request in a comment to post #167: "So I am already anticipating the next epysode: which I presume will deal with how this ancestral style or components of it were lost or transformed into other musical styles as the human journey progressed through the world."

Point well taken. If the genetic evidence points to the Pygmies and Bushmen occupying the deepest clades in the homo sapiens family tree, and their common ancestors, who would therefore have been our ancestors as well, were making music in P/B style anywhere from 70,000 to 150,000 years ago, then why do we find this style today only among Pygmies and Bushmen, why don't we find it practiced among a great many people throughout the world? In other words, why did music evolve in such a way that there are so many different styles of music making in different parts of the world? And why did the original style survive only among African Pygmies and Bushmen?

As I see it, the answer may be much simpler than anyone might suspect. If the presence of this very distinctive style is so strongly correlated with the genetic evidence, as certainly appears to be the case, then it would make sense to assume that its survival among certain populations, but not others, could have essentially the same cause as the survival of the ancient genetic markers among the same populations, but not others. And, by the same token, whatever changes took place in the musical stylistic markers over the millennia, among so many different populations, could stem either directly or indirectly from the same causes responsible for the changes in the genetic markers among the same populations. This makes more sense than it might seem when we realize that in both cases we are dealing with neutral markers, i.e., distinctive features (of music or genetics) that appear unrelated to evolution in the Darwinian sense, i.e., natural selection based on adaptation to the environment.

The above statement might be too abstract or technical for anyone to easily accept or even fully grasp at this point, but I'll toss it out here anyhow, as it might come in handy for future reference.

Another clue comes from the realm of linguistics, a basic principle of which I was unaware, until reading the following, from the Supporting Online Materials published with the Tishkoff group's latest paper:
Our observation that the Pygmies appear to share common ancestry with several Khoesan-speaking populations raises the possibility that the indigenous Pygmy language may have contained click consonants. A recent examination of the skeletal evidence for the development of the human vocal tract indicates that full human language capacity evolved before 50 kya but after 100 kya (S119). Considering that the normative directions of phonological evolution are from greater to lesser markedness, and that clicks are among the most marked of all sounds, the fact that click consonants exist at all in present day languages favors their existence back to the earliest human languages of 100-50 kya (p. 20).
What interests me here is the notion that the characteristic clicks of Khoesan, of which there are several distinct types, may well have been present in the earliest languages and subsequently lost -- because "the normative directions of phonological evolution are from greater to lesser markedness, and . . . clicks are among the most marked of all sounds." I was not aware of that phonological principle, but it interests me, because I see an analogy between Khoesan markedness and P/B musical style, which can also be understood as heavily "marked," in the sense that it would appear to contain far more distinctive features than any other type of music to be found in any other indigenous or "folk" repertoire. Could there be an "evolutionary" tendency, based on the same principle, for both languages and musical styles to lose "markedness," i.e., complexity and/or nuance, over time? This would correspond to what appears to have happened to P/B over time -- contradicting earlier notions of musical evolution based on the opposite view, that music begins with the simplest utterances and gradually evolves in the direction of increasing complexity.

Again, I think maybe I'm being too technical in the above, and also getting ahead of myself, so please allow me to start over once again:

The place to start is, obviously, Africa. And what I'd like to do next, rather than speculate further about basic principles, is to, more concretely, consider the distribution of P/B style, or musical styles similar to P/B in certain respects, on that continent. And yes, there are many groups in Africa that sing and/or play instruments in a manner resembling P/B -- though rarely in all respects. Here again we might want to pay close attention to "loss of markedness" since I think it might help us understand what can happen to a musical tradition over time.

(to be continued . . . )

Thursday, July 16, 2009

169. The Pygmy/Bushmen Nexus -- Part 9 -- Language vs. Music

Much of the population genetics research directed by Sarah Tishkoff places considerable emphasis on language. The relation between genetics and language is the theme of the 2007 paper, History of Click-Speaking Populations of Africa Inferred from mtDNA and Y Chromosome Genetic Variation, by Tishkoff et al., and the relationship among various Khoesan speakers is an important theme in The Genetic Structure and History of Africans and African Americans, where, as I've already mentioned, the very interesting question of whether the Pygmies might have originally spoken a Khoesan-related language is raised.

There is, in fact, no evidence whatsoever that any Pygmy group ever spoke any type of click language. And, as I've argued elsewhere on this blog, there is reason to believe the Pygmies never had a language of their own at all, possibly due to their having diverged from the ancestral group at a time prior to the development of fully syntactic speech -- a theory reinforced by the fact that whatever remnants of a shared Pygmy language have been identified consist solely of disconnected lexical elements with no trace of syntax.

Regardless of whether the Pygmies had their own language or whether it would have resembled Khoesan, the difficulty in determining the answers to such questions poses a problem for geneticists concerned, as is Tishkoff, with puzzling out the history of our earliest ancestors. If today's Pygmies were indeed in the habit of using click consonants, that would constitute very powerful cultural reinforcement of the theory of their archaic connection with the Khoesan-speaking Bushmen, which, as we have seen, has become an increasingly important theme in the population genetics literature.

Linguistics, along with archaeology, has always been important for population genetics. Some of Cavalli-Sforza's earliest research was in collaboration with historical linguists and from that time to this geneticists have always been eager to find correlations between patterns of linguistic association and those revealed by their own research. Why is this so important? First of all, because it's always better when findings from one field can be tested against those of another. Second, because the genetic results are not always as solid and consistent as could be desired, to the point that certain questions may have to be resolved by independent research in other fields, such as linguistics, archaeology, paleontology, etc.

And at this point I must confess that the results I've been sharing here are not as consistent as they might seem. For example, the phylogenetic tree from the Tishkoff paper of 2007, based on the mitochondrial findings, is accompanied in the same paper by a Y chromosome tree presenting a different picture, not completely consistent with the mitochondrial one. And while the comprehensive phylogenetic tree based on "D2" statistics, from Tishkoff's most recent paper, clearly places the Bushmen and Pygmy groups on its deepest branches, two other phylogenetic trees based on different statistical methods, published in a supplementary document, differ in significant ways from the first. The problem is that no algorithm has yet been developed for automatically producing unique phylogenetic trees from the genetic data, and different approaches to this problem can sometimes produce significantly different results.

Thus, without linguistic or archaeological evidence to more completely test the very special relationship between Pygmies and Bushmen so strongly suggested, but not unequivocally supported, by the genetic findings, the musical evidence becomes especially important. And in this case, as far as I am concerned, there can be no question. What the linguistic evidence fails to reveal, the musical evidence reveals in abundance -- and, as I hope my upcoming Ethnomusicology paper will convincingly demonstrate, there can no longer be any serious question regarding the common origin of the two musical traditions.

Wednesday, July 15, 2009

168. The Pygmy/Bushmen Nexus -- Part 8

At the risk of beating a dead horse, I'd like to present some additional findings, to make my point as forcefully as I can. I must add, however, that the genetic evidence is not always completely consistent and not every result presents the same picture. I'll have more to say on the interpretation of such anomalies a bit later.

We haven't yet seen any results representing purely male lineages, so let's take a look at a phylogenetic tree based on a comprehensive re-evaluation of the Y chromosome, published (in 2002) as Figure 1 in A Nomenclature System for the Tree of Human Y-Chromosomal Binary Haplogroups, by the "Y Chromosome Consortium":

(Again I'll remind you to right-click and select "Open link in a new window" to see an enlarged image.) While references to specific populations aren't given in this figure, a key to all the groups represented in this survey is provided in Table 2, on p. 346 and 347. The table contains 11 individuals referred to as "San" (i.e., Bushmen) as well as two each representing the Pygmy groups Biaka and Mbuti. Of the San, three are classified under A2*, with the others as A2b, A3b1, B2b1, and B2b4a. The Biaka are both classified under B2b4b, and the Mbuti under B2b* and E2b. With the exception of one Zulu individual classified under B2a1, none of the other groups represented belongs to either of the two deepest clades (branches), A or B. From the perspective of this particular survey of male lineages, therefore, we find a picture remarkably similar to what we've already seen from the mtDNA (i.e., female) and autosomal trees, with the Bushmen represented at the root of the tree (A), and Pygmy groups occupying the next deepest clade (B).

Here is one more mitochondrial tree, from a recent (2008) paper, The Dawn of Human Matrilineal Diversity, by Doron Behar et al., a project sponsored by the Genographic Consortium of the National Geographic Society:
The most obvious aspect of this tree is the emphasis on the striking division between the two deepest clades, LO and L1, and the clear division between "Khoisan" and "Non-Khoisan" populations, with the Khoisan groups limited to the deepest branches of the tree, LOd and LOk (consistent with Tishkoff's mtDNA tree, as we've already seen). In this case, the term "Khoisan" can be regarded as equivalent to what we've been referring to as "Bushmen." (N.B.: LSA stands for "Late Stone Age".) From my perspective, the most interesting aspect of this report are their references to the deep antiquity of the Khoisan lineages and their divergence estimate, as summarized in the abstract:
We paid particular attention to the Khoi and San (Khoisan) people of South Africa because they are considered to be a unique relic of hunter-gatherer lifestyle and to carry paternal and maternal lineages belonging to the deepest clades known among modern humans. Both the tree phylogeny and coalescence calculations suggest that Khoisan matrilineal ancestry diverged from the rest of the human mtDNA pool 90,000–150,000 years before present . . . (p. 1).
I've seen different estimates for the earliest divergence of Bushmen and/or certain Pygmy groups from the ancestral population, ranging from 35,000 years ago (Tishkoff) to from 72,000 to over 100,000 years ago (Chen), but this is the oldest and thus, to my mind, the most appealing. :-) If correct, then it would be possible to claim that our musical time machine might possibly take us back as far as 150,000 years into the past!

Naturally, you may complain that, despite the striking similarities of musical style among the various Pygmy and Bushmen groups of today, a recording of a particular performance by any one of them won't necessarily sound the same as what their ancestors would have sung back in the "stone age." And it's true, we have no reason to believe that any given song or any given configuration of musical notes is going to be exactly the same, since as we can already tell, no two recordings of contemporary Pygmy or Bushmen music are going to be note-for-note the same. Nevertheless, there are so many striking stylistic and structural similarities among all the groups I've been focusing on that it would be very difficult to see how the music of the ancestral population from whom all these various groups diverged, literally tens of thousands of years ago, could have seriously differed, stylistically or structurally, from what can be heard today. As I've already written in one of the earlier posts on this blog,
So what could the ancestors of the Pygmies and Bushmen have been singing 76,000 to 102,000 years ago? Would it have been something roughly similar, but perhaps more "primitive," maybe less intricately contrapuntal or not contrapuntal at all -- or perhaps not as well organized, less precise rhythmically, more loosely structured? Astonishingly enough, if the Pygmies and Bushmen of today indeed sing in a manner that even the experts find it difficult to distinguish, then it's hard to imagine how their common ancestors of 76,000 years ago could have been vocalizing much differently -- in any respect. Why do I feel so sure of this? Well, let's assume that the ancestral population had a different, or at least somewhat different, musical tradition at the time when the first group of Biaka Pygmy ancestors broke away from the "founder population," 76,000 to 102,000 years ago. Once the two groups had separated, then, in order for them to be so musically similar today, their music would have had to evolve in more or less exactly the same way despite the fact that they were no longer in contact with one another. And for the life of me I can think of no "sufficient reason" (to quote Liebnitz, whose "principle of sufficient reason" is one of the backbones of science) to explain such parallel evolution, or what evolutionists call "convergence." The only explanation that makes sense to ME is that the ancestral group must have been making music in a manner that would also be indistinguishable from "modern" musical practice, among their descendents, to the same experts, if they had had an opportunity to hear it.

We can only conclude that this particular musical tradition must have been passed down from generation to generation over a period of at least 76,000 years (assuming the genetic estimates are correct) essentially unchanged -- a conclusion that, if corroborated, would totally transform our notion of cultural evolution and the role of tradition in its history.

Monday, July 13, 2009

167. The Pygmy/Bushmen Nexus -- Part 7

(. . . continued from previous post.)
The so-called "Bushmen" peoples live in a completely different part of Africa than the Pygmies, centered in the Kalahari desert region of southwestern Africa, between Botswana and Namibia, though they are thought to have, at one time, been the dominant population of southern Africa as a whole. I've already commented on the striking similarity between their musical style and that of the various Pygmy groups in various posts on this blog. To refresh your memory (or if you're new), I'll refer you to Post 7, which contains links to specific audio clips from both groups along with a fairly extensive description of what I've come to call "Pygmy/Bushmen" style (P/B).

Already in 1956, Gilbert Rouget, then director of the Ethnomusicology program at the Musee de l'Homme, in Paris, prophetically wrote:
If, as it is traditional to do, one should consider the Pygmies and the Bushmen as belonging to two races entirely distinct, how can one explain the troubling relationship between their music and their dances? It cannot be a phenomenon of convergence, the resemblances constituting a system too complex and too coherent to allow for an explanation of this order. A reciprocal influence is also to be rejected, being given the distance as much geographic as climatic which separates the ones from the others. Is it necessary to believe, then, that the Pygmies and Bushmen are of common stock, and that their dance and music represent the remainder of a common cultural heritage?
Rouget's comments were published along with an LP record (currently out of print) directly comparing examples of the music of a Pygmy group, the BaBinga, and a much studied Bushmen group, the !Kung (now usually referred to as Ju'/hoansi), known for their adherence to what appeared to be a very traditional, possibly even "stone-age," lifestyle, and their unusual language, featuring many different types of click consonants (the ! in the name !Kung stands for one such click-type). I won't get into the details of the "great Kalahari debate" concerning the history of these peoples, as this has already been extensively covered both in this blog (see Table of Contents, above) and my paper on this topic. However, I do want to share with you some of the very compelling genetic evidence, which has led many to conclude that both the Ju'/hoansi Bushmen and most of the Pygmy groups do in fact have "pedigrees" linking them quite strongly to some of our earliest ancestors.

In a recent paper dealing with the genetic relationships among various African click-speakers, Sarah Tishkoff et al. present the following chart, based on those "haplogroups" (related sets of genetic markers) closest to the root of the mtDNA phylogenetic tree:

(As with most of the other images presented on this blog, you'll get a larger and much clearer picture by right-clicking and selecting "Open link in new window.")

The uppermost row lists each of the most important haplogroups, with those representing the deepest (thus oldest) branches to the left. The leftmost column lists the various African populations studied, grouped according to language family.

The first four haplogroups, labeled LOd, LOk, LOf and LOa, are, as you can see, offshoots from the leftmost branch of the tree. Under the first column, LOd, among the most ancient of surviving human mtDNA haplogroups, the !Kung Bushmen are represented by fully 96% of their sample. The groups listed under the names !Xun/Khwe and !Xun are also represented by large percentages, 61 and 51 respectively. Since !Xun is actually a variant spelling of !Kung, I'm assuming the two groups probably represent two nearby villages with essentially the same language and culture, with !Xun/Khwe representing a mixed sample of !Xun and Khwe speakers. Together, the !Kung, !Xun and !Xun/Khwe are the only Bushmen groups in the sample, though the other two "Khoisan" speakers, Hadza and Sandawe, are also hunter-gatherers. Note that no other population on the list is represented by more than 5% of its sample for this haplogroup. Moving to the next, LOk, we see that this haplogroup, also among the oldest on the tree, is found only among the three closely related Bushmen groups.

Moving down to the next language family, Niger-Kordofanian (of which the very widespread Bantu language family is a subgroup), we find three of the Western Pygmy groups, Mbenzele, Biaka and Bakola. With only one very minor exception (2% of the !Xun sample), none of these groups share any of their haplogroups with any of the Bushmen groups. In fact the great majority of the Western Pygmy sample (97%, 77% and 100%, respectively) can be found under haplogroup L1c, stemming from a completely different branch of the mtDNA tree than LOd or LOk. And in this case also, no other group is represented in this haplogroup by more than 5% of its sample.

Moving down the first column, we see, under the Nilo-Saharan family, the sole instance of Eastern Pygmies in the sample, the Mbuti. The majority of Mbuti (55%) are represented by yet another haplogroup, L2, not found at all among the Eastern Pygmies and in only relatively small percentages among the !Xun/Khwe and !Xun (17% and 16% respectively), possibly reflecting an archaic link to a remote common ancestor. In other words, when we compare the three groups, the Bushmen, the Western Pygmies and the Eastern Pygmies, we find that each has its own distinctive haplogroup or groups that set it apart from the other two, while the great majority of the Pygmy groups cluster along completely different branches of the phylogenetic tree (L1 and L2, as opposed to LO) from all the Bushmen groups.

The only important exception to this pattern appears to be haplogroup LOa, which cuts across several groups of both hunter-gatherers and farmers. While this haplogroup could conceivably stem from a truly archaic ancestor, it is among the haplogroups whose distribution seems, in the view of the authors, largely due to relatively recent gene flow (p. 2191). Given what we know about African history, most of the gene flow in such cases can be attributed to the relatively recent (over the last few thousand years) movements of large and aggressive farming populations across vast regions of the continent (e.g., the "Bantu expansion"), and is not likely to reflect direct, face-to-face associations among the much smaller and more reclusive hunter-gatherer bands, though such a possibility cannot be completely ruled out.

Very recently, Tishkoff and her collaborators completed a truly monumental study of 121 African and African American populations, by far the most extensive and ambitious project of its kind. This time, Tishkoff concentrated on nuclear microsattelite and insertion/deletion sites, a much richer, but also more complex, set of genetic markers than the mitochondrial and Y chromosome haplotypes that have dominated earlier studies. Their findings have just been published, under the title The Genetic Structure and History of Africans and African Americans, in the journal, Science. (Unfortunately you'll need to either subscribe or pay a fee to download this article.)

Figure 1 from this paper is a remarkable "neighbor-joining" phylogenetic tree, including all populations studied, based on "D2" statistics, the technicalities of which I am completely unable to describe since, very frankly, I have no idea how they work. I've reproduced the lowest, deepest, segment of this tree below. And as before I will urge you to right-click and select "Open Link in New Window," so you can view this image properly:

Once again, the Bushmen groups, labeled in this case San and !XunKxoe, occupy the lowest, thus deepest, branch of the tree, with the Pygmy groups just above them -- though, as before, stemming from a different branch. Here again, the Eastern Pygmies, represented by the Mbuti, occupy a branch of their own, with the Western Pygmies stemming from one sub-branch, and literally the rest of the world stemming from the other.

As far as the Pygmy groups in themselves are concerned, these new results are consistent with the findings by Destro-Bisol et al. that I've already described:
Shared ancestry of western and eastern Pygmies . . . was also supported by the phylogenetic trees . . . , consistent with mtDNA and autosomal studies
indicating that the western and eastern Pygmies diverged >18,000 years ago (p. 1041).
And as far as the relation between the Pygmies and Bushmen is concerned, one of their major findings, as stated in the abstract, is as follows: "Our data also provide evidence for shared ancestry among geographically diverse hunter-gatherer populations (Khoesan speakers [i.e., Bushmen] and Pygmies)." And, even more to the point, from the body of their text:
The shared ancestry, identified here, of Khoesan-speaking populations with the Pygmies of central Africa suggests the possibility that Pygmies, who lost
their indigenous language, may have originally spoken a Khoesan-related language, consistent with shared music styles between the SAK [i.e., southern African Khoesan] and Pygmies (p. 1041).
It might interest my readers to know that the reference given for "shared music styles" is to the book Folk Song Style and Culture, by Alan Lomax et al., a reference I provided at Tishkoff's request. To my knowledge this is the first instance of a reference to the musical evidence appearing in any of the genetic literature. Hopefully it will not be the last.

Sunday, July 12, 2009

166. The Pygmy/Bushmen Nexus -- Part 6

(. . . continued from previous post.)
In case its full significance might have eluded you, I'd like to repeat the last sentence of the "Author's Summary" as quoted in the previous post, with some added emphasis: "This finding suggests that the shared physical and cultural features of Pygmies were inherited from a common ancestor, rather than reflecting convergent adaptation to the rainforest.." The most obvious of the shared physical features is, of course, short stature. The gene or genes controlling human stature have not yet been isolated, but given the shared lineage implied by both the mitochondrial and autosomal (i.e., nuclear) DNA evidence it seems safe to infer that both the Eastern and Western Pygmies inherited their short stature from a common ancestor.

An alternative theory popular among anthropological "revisionists" is that the Pygmies as such do not really have a shared lineage but are simply Bantus whose ancestors happened to settle in forest areas. According to this line of thinking, their short stature is the result of convergent evolution, i.e., totally independent but very similar processes stemming from the adaptation of each group to the special conditions of life in the tropical forest.

It's important to note, at this point, that there is no way of proving beyond the shadow of a doubt that the common ancestor of today's Pygmies was short. There will always remain the possibility of convergent evolution, even if it can be proven that they all share a common ancestor -- because, strictly speaking, we have no way of proving that ancestor could not have been tall. Which brings me to a very important, though often overlooked, aspect of modern science, a principle known as "Occam's Razor," which has been summarized as follows: "one should not increase, beyond what is necessary, the number of entities required to explain anything."

The basics are explained in a particularly clear online discussion by Francis Heylighen:
[Occam's Razor] underlies all scientific modelling and theory building. It admonishes us to choose from a set of otherwise equivalent models of a given phenomenon the simplest one. . .

Though the principle may seem rather trivial, it is essential for model building because of what is known as the "underdetermination of theories by data". For a given set of observations or data, there is always an infinite number of possible models explaining those same data. This is because a model normally represents an infinite number of possible cases, of which the observed cases are only a finite subset. The non-observed cases are inferred by postulating general rules covering both actual and potential observations.
An excellent example of Occam's Razor is provided by the application of Newton's principle of universal gravitation to our understanding of the planetary orbits. Strictly speaking the ancient Ptolemaic theory of planetary epicycles, based on an Earth-centered universe, could, in Newton's day, account just about as accurately for the planetary movements as Newton's theory. Without a principle such as Occam's Razor, we might want to consider both theories as equally acceptable, since both are capable of fully accounting for the data. However, Newton's explanation, being far simpler than that of Ptolemy, satisfied Occam's Razor, and thus became universally accepted in his day -- despite the fact there was, at that time, no way of knowing for sure that the planets did not revolve around the Earth in complex epicycles after all.

Thus, according to very basic scientific principles, when we reach a point that two or more theories account equally well for all the evidence, Occam's Razor more or less compels us to accept the theory offering the simplest explanation. Which does not rule out the possibility that new evidence might some day arise that might force us to reconsider.

All too often in the social sciences we find people who are unaware of Occam's Razor, or believe they can easily ignore it, assuming it's necessary to demonstrate the impossibility of every alternative before any theory can be accepted. Not true. All that should be necessary to establish a given theory is to demonstrate 1. that it fully accounts for all the currently available, relevant, evidence; and 2. that it presents a simpler explanation than any alternative which may also happen to account for the same evidence. That doesn't mean the theory is necessarily proven, i.e., true for all time. Absolute proof, contrary to popular opinion, is not the objective of scientific inquiry.

I would now like to return to the sentence quoted at the beginning of this post, but with a different emphasis: "This finding suggests that the shared physical and cultural features of Pygmies were inherited from a common ancestor, rather than reflecting convergent adaptation to the rainforest.." The inclusion of the term "cultural" opens up a whole new vista, rarely considered in the genetic research, but definitely worth considering here. Because, despite the indifference of most ethnologists to this line of research, it most certainly has relevance for our understanding of culture and cultural evolution, which, operating via ancestral traditions passed down from generation to generation must also be regarded as "genetic."

While Patin et al. focus on cultural practices associated with subsistence, such as hunting, gathering, honey collecting, etc., other distinctive cultural features, such as nomadism, acephalous leadership, egalitarian social structures, gender equality, non-violent behavior patterns, and, of course, distinctive modes of dancing and music-making, would also, according to the same set of findings, and the same scientific (i.e., Occam-based) logic, be due to inheritance "from a common ancestor."

Consequently: if the simplest interpretation of the genetic evidence points to a common ancestor for all Pygmy groups, and the simplest interpretation of that finding points to the same common ancestor as the most likely source of all the other commonalities, both physical and cultural, then we may safely infer that our musical "time-machine" takes us back at least 18,000 years into the past, i.e., well into the Upper Paleolithic. But that's only the beginning -- because we have yet to factor the Bushmen and their music into the equation.
(to be continued . . . )

Saturday, July 11, 2009

165. The Pygmy/Bushmen Nexus -- Part 5

(. . . continued from previous post.)
Destro-Bisol's research was based on Mitochondrial DNA (mtDNA), inherited strictly along the female line. A more recent study, published this year, by Etienne Patin et al, was based on a wider range of markers, found in the cell nucleus and X chromosome, representing descent from both parents combined. Though the focus of the study was a comparison of African Pygmies and farmers, the data representing the various Pygmy groups tends to bear out Destro-Bisol's mtDNA findings.

Before considering any more genetic evidence, however, let's take a closer look at the various Pygmy populations. While the African Pygmies can be divided into two large groups, Eastern and Western, there are subdivisions of each, especially among the Western group, each subdivision constituting a separate population, with its own history, traditions, language, etc. Among the best known, in the Central African Republic can be found the Aka (also known as Biaka), BaBinga and Ba-Benzélé; in Cameroon, Gabon and the Republic of Congo, the Baka (sometimes confused with the Aka), Bedzan and BaKola; in the Ituri Forest, far to the east, we have the Mbuti, Efé, Asua and BaKongo; also to the East, in Ruanda and Uganda, the Ba-Twa. It must be noted that there is a certain amount of confusion regarding the naming and classification of the various Pygmy groups, so that we can find different names and even different groupings when consulting various sources.

We are now in a better position to interpret the Patin group's results, as encapsulated in Figure 2 from their paper. (If you right-click and select "Open link in new window," you'll get a more readable version of this image.)
As you can see, seven Pygmy groups are represented in the uppermost diagram, BaKola, G. Baka (Baka from Gabon), C. Baka (Baka from Cameroon), Biaka (or Aka), Mbuti, Northern Twa and Southern Twa. Each of the four graphs in the upper diagram represent different degrees of detail in the evaluation of the genetic markers. The most detail can be found in the lowermost graph, labeled K = 5, which is therefore the most useful for our purposes.

The very strong genetic difference between Western and Eastern Pygmies, as noted by Destro-Bisol, is clearly seen here in the contrast of color between the first four groups, colored mostly in green, and the Mbuti, colored mostly red. The next two, both representing the Twa, present a more complex picture, with streaks of both red and orange. The remaining groups, colored mostly in orange, are non-Pygmies, mostly Bantu speaking farmers.

(The lowermost diagram, labeled B, presents a simplified model in which most individuals of mixed ancestry were excluded -- as you can see, the Twa groups, now almost compeletely red, fit more clearly with the Mbuti.)

The Patin group's conclusions are succinctly summarized in the "Author's Summary" on page 2:
By means of simulation-based inferences, we show that the ancestors of Pygmy hunter–gatherers and farming populations started to diverge 60,000 years ago. This indicates that the transition to agriculture—occurring in Africa 5,000 years ago—was not responsible for the separation of the ancestors of modern-day Pygmies and farmers. We also show that Western and Eastern Pygmy groups separated roughly 20,000 years ago from a common ancestral population. This finding suggests that the shared physical and cultural features of Pygmies were inherited from a common ancestor, rather than reflecting convergent adaptation to the rainforest.. ("Inferring the Demographic History of African Farmers and Pygmy Hunter–Gatherers Using a Multilocus Resequencing Data Set," by Etienne Patin et al., in PLoS Genetics, April 2009, Volume 5, Issue 4, p. 2).
This is a result closely consistent with the findings of the Destro-Bisol group, who estimated the divergence of Western from Eastern Pygmies at roughly 18,000 years ago. Note also, that both Pygmy groups appear to share a common ancestor, estimated to have diverged from the ancestor of the farming populations at a much earlier date, roughly 60,000 years ago.

As far as the music is concerned, the Biaka (Aka), BaBinga, BaBenzélé, Baka, and Mbuti, representing both the Western and Eastern Pygmies, all share essentially the same style, characterized most distinctively by the use of elaborately interlocking vocal parts and yodel, though detailed study would be needed to determine whether or not there are significant differences among them with respect to certain other aspects of either musical structure or cultural context. The Bedzan would appear to share a very similar style, though for some reason, unlike any of the others, they apparently do not yodel. Since all these groups seem to have had a common ancestor roughly 18,000 to 20,000 years ago, it's not difficult to conclude that their shared musical style must, in all likelihood, be at least that old. (We're not done, of course, since we still have the Bushmen to consider.)

The only Pygmy group known to me that vocalizes in a clearly different manner are the BaTwa, who sing in the call and response style so common for most Bantu groups and indeed, as is evident from the above diagram, appear to have heavily intermixed with neighboring Bantu peoples over many years. As Patin et al. have written,
With respect to the two populations of Twa Pygmies, they clearly
clustered with South-East African farmers for K=4, consistent with these Pygmy groups being admixed (some anthropologists describe them as ‘‘Pygmoids’’), and with the complete shifting of their cultural practices towards those of neighboring agricultural populations . . . (ibid., p. 3).
I am not familiar with the music of the other Pygmy groups. But since the BaKola too appear to be heavily intermixed genetically with neighboring Bantu peoples, it's possible that they too may no longer sing in the more distinctive and complex Pygmy manner.

(to be continued . . . )

Tuesday, July 7, 2009

164. The Pygmy/Bushmen Nexus -- Part 4

Much has been made recently of the discovery, in Germany, of a bone flute dated to approximately 35,000 years ago (see article in Science News, June 25: Paleolithic Bone Flute Discovered: Earliest Musical Tradition Documented In Southwestern Germany).
"These finds demonstrate the presence of a well-established musical tradition at the time when modern humans colonized Europe, more than 35,000 calendar years ago," the authors write in the journal Nature. "Other than the caves of the Swabian Jura, the earliest secure archaeological evidence for music comes from sites in France and Austria and post-date 30,000 years ago."
The archaeologists have no idea how the flute sounded, or what sort of music it made, though they found someone who figured out how to play the opening of the "Star Spangled Banner" on it. An important find, certainly. But hardly a time machine. Looking at a picture of this flute or listening to it play our national anthem will not take you back 35,000 years. But this should hardly be surprising. Time machines don't actually exist, do they?

Well, actually, they don't. There's no way to literally put yourself back into the past or forward into the future (though if you're patient you'll move into the future on your own, without needing a machine). But there is a way to listen in on sounds humans were making 35,000 years ago, 50,000 years ago, probably even 100,000 years ago -- and beyond.

Let's return to the words of ethnomusicologist Simha Arom: "Right from the beginning, I sensed that this music existed in us all, like some Jungian archetype.” I assume you've gathered by now that he's referring to the music of the African Pygmies. Of his first experience of hearing Pygmy music, from a hotel room in the capital of the Central African Republic, Arom wrote:
I felt that their music came from the back of time, but also, to a certain extent, from my own depths. Yet I could never have known it, never having heard anything like it before. It was insane. How did the musicians achieve this? I was dumbfounded.
So. Music "from the back of time." Music from "my own depths." Music that already "existed in us all." Music that functioned "like some Jungian archetype." Bold words. But what can they mean? (And what is a Jungian archetype anyhow?)

It's one thing to have a feeling about a musical experience, another thing entirely to demonstrate that your feeling could be more than just a feeling, that it might pertain to something real, something that can actually be investigated systematically, that can be researched and tested.

Let's begin with a simple observation. The music Colin Turnbull describes in his classic, The Forest People, is that of the Mbuti Pygmies, living in the Ituri Forest of the Democratic Republic of Congo (formerly Zaire). The strikingly similar music studied by Simha Arom is that of the Aka Pygmies, living far to the west, in the forests of the Central African Republic. The Mbuti and Aka are representative of two completely different Pygmy groups, usually referred to, respectively, as "Eastern" and "Western."

According to a recent study by Giovanni Destro-Bisol et al,
The two principal groups are represented by Eastern Pygmies (32,000 individuals; Murdock 1959), who settled in Zaire, and by Western Pygmies (27,000 individuals; Murdock 1959), who settled in the Cameroon, Congo, and CAR. The two groups differ both biologically and culturally. The Eastern Pygmies are even smaller in stature than Western Pygmies (144–145 cm vs. 152–155 cm in males, on average) and also have lighter skin and a narrower nose.("The Analysis of Variation of mtDNA Hypervariable Region 1 Suggests That Eastern and Western Pygmies Diverged before the Bantu Expansion," in The American Naturalist, February 2004.)
DNA analysis by this group led them to conclude as follows:
The comparisons of haplogroup frequencies among the Western Mbenzele Pygmies, Western Biaka [Aka] Pygmies, and Eastern Mbuti Pygmies indicate a lack of any particular affinity between Western and Eastern Pygmies . . .
The Western Mbenzele Pygmies and Western Biaka Pygmies completely lack the L2 haplogroup and the L1e haplogroup, which are both found at high frequencies among the Eastern Mbuti Pygmies (Vigilant et al. 1991; Watson et al. 1997). However, the haplogroup L1c, observed at high frequencies in the Western Pygmies, was undetected in the Eastern Mbuti Pygmies (pp. 217-218).
The investigators conclude that the most reasonable explanation for "the observed differences in haplogroup frequencies" is "[t]he long reciprocal isolation between the two Pygmy groups," an isolation dating, in their estimate, to at least 18,000 years ago (p. 224).

(to be continued . . . )