Integrity and Origin of East African “Khoisan” Populations: Linguistic, Archaeological, and Genetic Approaches

The hunter-gatherer populations of Africa have long been the subject of significant curiosity. From initial

contact with European colonial invaders, “Bushmen” have been viewed as living fossils, sole survivals of remnants

of ancient and primitive life-ways, and therefore exceptionally valuable for interpretation of the archaeological

record. The extreme isolation, until relatively modern times, of these populations, in addition to their nomadic

foraging lifestyle and limited material culture, their unique click-languages and tradition of rock-painting have

inspired extensive research and theorizing. The majority of these populations live in southern Africa, but the

existence of two “extant” groups, the Sandawe and the Hadze, in east Africa has survived as a further intrigue for

researchers, who, having assumed on linguistic grounds a high affinity between the groups have sought

corroborative archaeological and genetic evidence. Theories as to the nature of the relationship between the

Hadze, Sandawe, and the SAK (South African Khoisans) have been largely conjectural, although passionately

argued. The demonstration of affinity enables the transference of ethnoarchaeological models from the better-

studied southern groups to those in east Africa; namely, rock-art interpretation. Queries into continuity,

conservation, and trajectory of development in regard to language and physiological factors such as morphology

and immunology are valuable for the insight that they will presumably shed upon larger issues of ethnicity, race,

and migration. The multi-disciplinary studies into these populations provide critical opportunities not only to

synthesize, but to analyse such syntheses; to examine the integration of the differing bodies of data and

approaches, to corroborate conclusions or determine if such can be done and to appraise the academic interaction

of such relationships.

The idea that Khoisan populations once sparsely inhabited the majority of eastern and southern Africa,

reaching from Ethiopia to the Cape, and that these contemporary populations are the last remnants is prevalent in

archaeological, linguistic, and genetic approaches. The idea that east Africa can be considered the “homeland” or

point of “origin” for all Khoisan populations – who, according to some interpretations, are representative of the

earliest of behaviourally if not anatomically modern humans has diffuse historical and political, not to mention

academic, origins. (Schepartz 1988, 58) Previous interpretations and the conclusions that they have sought are

critical to this discussion in regards to bias and motive: most notably, the widespread notion of Khoisans as

analogues for Pleistocene foraging populations in ethnographic analogy. Efforts to demonstrate a cultural and

linguistic continuity or “pan-San” cognitive/cosmological system are characterized by Lewis-Williams' shamanistic

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interpretation of Tanzanian rock-art, potentially as old as 30 kyr, with reference to rituals of contemporary SAK

populations. The most extrapolative of theories conjecture about the role of click languages as a “proto-language”

for the earliest of modern human populations; the inference of the philosophical premise of a “Mother Tongue”

being inferentially related, with the assumption of not only continuity but conservation. On the other extreme is

the argument that the majority of these apparent similarities are distorted misinterpretations based on inaccurate

and prejudiced observations that have since been retained due to their romantic appeal rather than inherent

validity.

Linguistic definitions

“Click languages”, in which fricative sounds are used phonemically (Traunmuller 2003, 1) are the major

unifying factor for tribes considered Khoisan. Such languages, over 30 of which are known, are unique to Africa and

were first classified in Greenberg's seminal 1963 study (Morris 2003, 87). While various schemes classify the

languages in three to six groups, lineages models are undetermined and some linguists, notably Westphal, doubt

whether they constitute only one family (Traunmuller 2003, 2). Extremely rich, Khoisan click-languages are “among

the most elaborated of all on Earth” (Traunmuller 2003, 3) inferring a relatively ancient origin. The southern

languages display greater integrity as a group; the Hadze and Sandawe languages are considered isolates, although

the Sandawe language is more similar to the southern languages than to Hadze. (Tishkoff 2007, 2180). Ehret

estimates the initial divergence of the languages to at least 20 kya (Tishkoff 2007, 2180) and, although other

linguists have not reached a consensus, suggests that the Hadze/Sandawe division is the more ancient as it is “less

innovative” than SAK languages (Morris 2003, 87) It has been suggested that click languages were developed for

hunting as the sounds, not initially recognizable as human to a human ear, may not immediately register to the

prey as being produced by a predator (Traunmuller 2003, 4). While the occasional use of click-sounds have

diffused into the Bantu languages of varying populations, the ability to produce the full repertoire of clicks as

employed by the Khoisan requires distortions of the tongue that inhibit adult borrowing (Knight 2003, 470). The

suggestion that an anatomical feature, a gently sloping alveolar ridge in the palate which reduces the necessary

distortion of the tongue is, if not unique, then at least more common in Khoisan populations (Traunmuller 2003, 4)

as a mutation or retention is of particular interest in the debate as to whether click-phonemes should be

considered a primitive or derived trait.

Archaeology and Ethnography

The Sandawe population living in the Kondoa region of northern Tanzania is currently estimated at roughly

30,000. Although still distinct from the surrounding Bantu-descended populations they have recently adopted

agriculture. (Tishkoff 2007, 2180) Relatively nearby, although having little evidence of contact, are the the Hadze

(also referred to as Hadzapi or Kindiga) who live near the Lake Egasi in the Arusha district of northern Tanzania and

are estimated at less than a thousand (Tishkoff 2007, 2180). Fosbrooke described them, based on a brief visit in

1950 and by reference to previous literature, as “a people only now emerging from the Stone Age”, noting their

material culture as “of the sketchiest” and their continued adherence to a foraging subsistence pattern with no

permanent settlements and seasonal movement to follow game and plants (1956, 3). The San and Khoikhoi are

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conglomerate terms that refer to a variety of tribes initially described in South African colonial encounters as

“Bushmen” or “Hottentot”. Hottentots were “the taller, more robust, and narrow-headed” (Hausman 1982, 315)

and assumed to be of substantially “different stock” based upon their morphology. (Hausman 1982, 315) Early

ideas on their evolutionary origins and significance focused on anatomy and attempted to map these races to

Pleistocene fossils, postulating two early distinct racial types of proto-Khoisans, often resulted in the idea of the

Khoisan as a “desert ecotype” that migrated south. Subsequent study revealed not only the inadequacy of

available specimens to draw any such conclusions but nonempirical nature of analysis that had been applied

(Schepartz 1988).

Traditionally, the lack of artefacts associated with agricultural communities in Khoisan/foraging

assemblages was taken to prove lack of contact between the communities. The nature of interaction, however,

may not have followed traditional economic relationships, nor that of the assumed marginalization. Evidence of

ideological syncretism alongside genetic flow is leading to more subtle models of symbiotic relationships between

technically discrete populations. Jolly (1996) details the implications that such symbiosis have on our

understanding of Khoisan identity; this has crucial ramifications for conceptualizations of the Hadze and Sandawe –

and their ethnic integrity. The characterization of Khoisan peoples as highly territorial and fiercely independent

may be related to relatively recent politics. Bushmen were noted to strongly resist colonial expansion and were, in

result, the victims of harsh subjugation and genocide. The degree to which this may have modified their culture,

including internal revisionism on behalf of the survivors, is difficult to assess – but should be kept in consideration,

particularly as the majority of socio-cultural data, including the ubiquitous work of Bleek, are biased ethnohistoric

records from the colonial era.

Looking further back in time, there are more reasons to question the assumption of cultural isolation or

biological stasis – particularly from the archaeology. The Holocene/Pleistocene transition was marked by dramatic

climatic change, as evidenced by environmental and ecological data including pollen studies that demonstrate,

around 10-15 kyr, temperature fluctuations of more than 5°C within periods as short as decades that would

undoubtedly have had drastic demographic consequences. (O'Connell 1999, 10562) Archaeology of foraging

groups demonstrates significant change from the mid-Holocene onwards, including expansion and intensification

of resource exploitation and markedly higher local population densities (O'Connell 1999, 10563). Mitchell (2002)

notes that recent hunter-gatherer ethnoarchaeology emphasizes ideological and social similarities at the expense

of ecological themes, ignoring their determinant role and the variations between different foraging communities,

resulting in significant downplay of contrasts between the late Pleistocene and Holocene LSA foraging populations

– much less the similarities between contemporary societies and their predecessors.

Genetics

Studies of population genetics began to resemble their current form 40 years ago with the identification of

gene polymorphisms, loci for blood groups, protein, enzyme, and immunological variations, and extensive

sampling (MacEachern 2000, 359). Early comparative works, notably Cavalli-Sforza's extensive analysis in 1994 in

which the Khoisan groups were first focused upon, were intended to provide an alternative to archaeological and

linguistic models to historical questions of ancestry and considered the superior method for tracing population

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movements – resulting in a return to migratory explanations, which had largely fallen out of favour. With the

recent intensification of genetic studies, the fundamental question of whether the units scrutinized in one

approach correspond to those identified in another remains troubling. Genetic studies in general are continually

eroding our preconceived notion of race, revealing it to be a continuum of variation as opposed to a discrete

system of classification. (MacEachern 2000, 358) A practical, interdisciplinary definition of “ethnicity” has yet to be

identified. As such, the results of even the most scientifically rigorous of genetic studies are interpretable in a wide

variety of ways with the same studies cited to different purposes.

Y-chromosome and mtDNA studies have consistently demonstrated that the genetic distance between

Khoisan populations is incredibly great. Knight et al said that the Hadze and SAK are “separated by genetic distance

as great or greater than that between any other pair of African populations” (2003, 470) and that the split

“appears to be one of the oldest of human population divergences” (2003, 469). Tishkoff's 2009 study estimates

the split between Hadze and SAK at 56 kyr, Hadze and Sandawe at 21 kyr, and Sandawe and SAK at 44-50 kyr and

presented three different divergence scenarios. Although, relative to the majority of African populations which

demonstrated a high degree of mixed ancestry, all Khoisan populations could be considered significantly isolated;

the Sandawe and Hadze demonstrated greater recent admixture with the neighbouring non-click Tanzanian

populations than with each other. All three of these studies showed little to no evidence of recent gene flow

between the two east African click-groups. The Sandawe and SAK share no identical mtDNA haplotypes, further

refuting the possibility of recent genetic flow, and the haplotypes shared by the Sandawe and Hadze are only those

which are common in surrounding populations. (Tishkoff 2007, 2186) The regions of shared genetic material

between the Sandawe and Hadze are referred to by Tishkoff (2007) as among the “most basal of clades” and an

unusually high amount of “private alleles” which, completely absent from other populations, the Khoisan share

only with each other. The fact that the Ethiopian population shows greater similarity to Khoisans than does any

other African population is taken as further evidence of east African Khoisan origin. Y-chromosomes studies have

shown a portion of the Ethiopian population to have great affinity with Khoisans in the “deepest clades”, although

the majority of Ethiopian Y-chromosomes link them to the first migration out-of-Africa and subsequent migratory

“backflow” from Asian populations. (Semino 2002)

These conclusions must be taken in context of greater debate as to the significance and interpretation of

such genetic studies. While Wood et al found Y-chromosome analyses to demonstrate more correlation between

linguistics and genetics than between geography and genetics, globally, they noted the inconsistency of studies

applied to Africa (2005, 2). Kittles suggests that major African population divergences occurred long before

significant migration out of the continent and is highly critical with attempts to match these to racial categories,

being defined by morphology not necessarily reflected at the same genetic level. (1999, 90) Tishkoff et al (2007)

stated that geographic and genetic distances showed conclusive correlation and went so far as to estimate dates

for the origin of modern humans at 200 kya and the major ut-of-Africa migration at 100 kya. Other studies have

preferred to theorize on “pulsation” migration patterns (Cavalli-Sforza 1997) and, acknowledging the not

necessarily stable rate of mutations, calibrate divergence dates with the palaeoanthropological record

(MacEachern 2000). Of most pertinent interest to this discussion is the relatively smaller size of Khoisan

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populations as the effect of such small sample sizes, as well as genetic drift, have yet to be fully ascertained (Kittles

1999, 90).

Discussion

While it is easy to muster evidence to shed doubt upon the proposed model – of an east African origin and

subsequent southern migratory expansion of a click-speaking Khoisan population, who has since retained

significant and diagnostic cultural, if not anatomical, features – there is, as of yet, no better explanation for the

similarities between the Sandawe and Hadze groups and with the southern Khoisan. The rarity of click languages,

existing nowhere else on the globe alongside the significant vocabulary overlap between click-languages that,

based upon genetic models of population movement, cannot be a result of borrowing or diffusion and demands an

explanation. The majority of evidence argues against the isolated evolution, or even transference, of clicks

between the Sandawe, Hadze, and SAK and the same evidence seems to point to the Sandawe and Hadze

demonstrating greater divergence age than the SAK. Precisely how this relates to questions of geographical origin

or varying rates of cultural conservation is, as of yet, unclear. Overwhelmingly, the notion of a Khoisan grouping –

be it racial, ethnic, or another more politically-appropriate label – stands, yet many of the presumed associations

must be dropped.

Bibliography

Cavalli-Sforza, L. (1997) Genes, Peoples, and Languages, Proceedings of the National Academy of Sciences 94: 7719–7724

Chen, Y. et al (2000) mtDNA Variation in the South African Kung and Khwe – and Their Genetic Relationships to Other African Populations, American Journal of Human Genetics 66: 1362-1382

Deacon, H. (1992) Southern Africa and Modern Human Origins, Philosophical Transactions: Biological Sciences 337: 177-183

Fosbrooke (1956) A Stone Age Tribe in Tanganyika, The South African Archaeological Bulletin 11: 3-8Henn, B. et al (2008) Y-chromosomal evidence of a pastoralist migration through Tanzania to southern Africa,

Proceedings of the National Academy of Sciences 105: 10693-10698Hausman A. (1982) The Biocultural Evolution of Khoisan Populations of Southern Africa, American

Journal of Physical Anthropology 58:315-330Henn, B. et al (2008) Y-chromosome evidence of a pastoralist migration through Tanzania to southern Africa,

Proceedings of the National Academy of Sciences 105: 10693-10698Jolly, P. (1996) Symbiotic Interaction between Black Farmers and South-Eastern San: Implications for Southern

Rock Art Studies, Ethnographic Analogy, and Hinter-Gatherer Cultural Identity, Current Anthropology 37: 277-305

Keita, S and R. Kittles (1997) The Persistence of Racial Thinking and the Myth of Racial Divergence, American Anthropologist 99:534-544

Kittles, R. and S. Keita (1999) Interpreting African Genetic Diversity, The African Archaeological Review 16: 87-91Knight, A. (2003) African Y Chromosome and mtDNA Divergence Provides Insight into the History of Click

Languages, Current Biology 13: 464-473Kusimba, S. (2005) What Is a Hunter-Gatherer? Variation in the Archaeological Record of Eastern and Southern

Africa, Journal of Archaeological Research 13: 337- 366Lewis-Williams, J. (2002) A Cosmos in Stone: Interpreting Religion and Society Through Rock Art Walnut Creek: Alta

Mira PressMacEachern, S. (2000) Genes, Tribes, and African History, Current Anthropology 41: 357-384Mitchell, P. (2002) Hunter-gatherer archaeology in southern Africa: recent research, future trends, Before Farming

3: 1-18

5 -- Tankard 2009

Morris, A. (2003) The Myth of the East African 'Bushmen', The South African Archaeological Bulletin 178:85-90

O'Connell, J. (1999) Genetics, archaeology, and Holocene hunter-gatherers, Proceedings of the National Academy of Sciences 96: 10562-10563

Semino, O. (2003) Ethiopians and Khoisan Share the Deepest Clades of the Human Y-Chromosome Phylogeny, American Journal of Human Genetics 70: 265–268,

Shepartz, L. A.(1988) Who were the later Pleistocene eastern Africans?, The African Archaeological Review 6:57-72

Solomon, A. (1997) The Myth of Ritual Origins? Ethnography, Mythology, and Interpretation of San Rock Art, The South African Archaeological Bulletin 52: 3-13

Tishkoff, S. et al (2007) History of Click-Speaking Populations of Africa Inferred from mtDNA and Y Chromosome Genetic Variation, Molecular Biology and Evolution 24: 2180-2195

Tishkoff, S. et al (2009) The Genetic Structure and History of Africans and African Americans, Science 324: 1035-1044

Traumuller, H. (2003) Clicks and the idea of a human protolanguage, PHONUM 9 :1-4Wood, E. et al (2005) Contrasting patterns of Y chromosome and mtDNA variation in Africa: evidence for

sex-biased demographic processes, European Journal of Human Genetics 1-10

6 -- Tankard 2009