AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 00:00–00 (2014)

Questions of Khoesan Continuity: Dental Affinities Among the Indigenous Holocene Peoples of South Africa Joel D. Irish* Research Centre in Evolutionary Anthropology and Palaeoecology, School of Natural Sciences and Psychology, Liverpool John Moores University, Liverpool L3 3AF, UK KEY WORDS Africa

dental anthropology; phenetic affinity; population history; Khoesan; South

ABSTRACT The present report follows up on the findings of previous research, including recent bioarchaeological study of well-dated Khoesan skeletal remains, that posits long term biological continuity among the indigenous peoples of South Africa after the Pleistocene. The Arizona State University Dental Anthropology System was employed to record key crown, root, and intraoral osseous nonmetric traits in six early-through-late Holocene samples from the Cape coasts. Based on these data, phenetic affinities and an identification of traits most important in driving intersample variation were determined using principal components analysis and the mean measure of divergence distance statistic. To expand biological affinity comparisons into more recent times, and thus preliminarily assess the dental impact

of disproportionate non-Khoesan gene flow into local peoples, dental data from historic Khoekhoe and San were also included. Results from the prehistoric comparisons are supportive of population continuity, though a sample from Matjes River Rockshelter exhibits significant, albeit slight, phenetic distance from other early samples. This and some insignificant regional divergence among these coastal samples may be related to environmental and cultural factors that drove low-level reproductive isolation. Finally, a close affinity of historic San to all samples, and a significant difference of Khoekhoe from most early samples is reflective of documented population history following immigration of Bantu-speakers and, later, Europeans into South Africa. Am J Phys Anthropol 000:000–000, 2014. VC 2014 Wiley Periodicals, Inc.

Until a relatively recent reboot of bioarchaeological research on the indigenous Holocene inhabitants of South Africa, the consensus peopling scenario could be summarized as follows. Terminal Pleistocene/Early Holocene peoples appeared phenotypically similar to the modern Khoesan, though of larger body size (Tobias, 1966, 1972, 1974; Clark, 1970; Br€ auer and Rosing, 1989). It is from this “large” Khoesan ancestor that antecedents of modern San and Khoekhoe (Brothwell, 1963), perhaps among other sub-Saharan Africans (Tobias, 1966, 1972, 1974), had developed by 12,000–10,000 BP1 (Tobias, 1966, 1972, 1974, 1985; Clark, 1970; Br€ auer, 1978; Inskeep, 1979; Nurse et al, 1985; Phillipson, 1985). Skeletal remains maintained to represent these “small” Khoesan were dated to 11,000 BP at Matjes River Rockshelter (Clark, 1970; Br€ auer, 1984), and about 10,000 BP at Border Cave and Tuinplaats (Inskeep, 1979). Finally, the Khoekhoe and San began to diverge 3,000–2,000 years ago when the former turned to herding while the latter maintained a foraging lifestyle (Parkington, 1981; Ehret, 1984; Denbow and Wilmsen, 1986). Over the past several decades, as detailed elsewhere (Pfeiffer and Sealy, 2006; Stynder, 2006, 2007, 2009; Stynder et al., 2007), new fieldwork, reinterpretations of the archaeological record, wide-ranging radiocarbon dating of many previously recovered skeletal remains, and

morphometric study of these newly contextualized remains have yielded a much clearer picture of the region’s Holocene population history. For starters, this renewed bioarchaeological focus suggests that the Terminal Pleistocene/Early Holocene South Africans were likely of local late Pleistocene origin (Morris, 2002, 2003; Stynder et al., 2007)—in seeming opposition to the idea of an older, more widespread ancestral population (Sutton, 1981; Ehret and Posnansky, 1982; Nurse et al, 1985). It is also said that these people were the precursors of later South African Khoesan only (Morris, 2002, 2003), not a source for all sub-Saharan populations as once thought (Tobias, 1966, 1972, 1974, 1985; Clark, 1970; Br€ auer, 1978; Inskeep, 1979; Nurse et al, 1985; Phillipson, 1985). These ostensibly contradictory scenarios are actually reconcilable in light of recent genetic research (Schuster, 2010; Pickrell et al., 2012;

Grant sponsor: National Science Foundation; Grant number: BCS-0840674. *Correspondence to: Prof. Joel D. Irish, Research Centre in Evolutionary Anthropology and Palaeoecology, School of Natural Sciences and Psychology, Liverpool John Moores University, Byrom Street, Liverpool, L3 3AF, United Kingdom. E-mail: [email protected] Received 17 February 2014; accepted 21 April 2014

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All dates reported in this paper are uncalibrated, following standard practice (Sealy and Pfeiffer, 2000; Stynder et al., 2007), to allow for consistency with previous South African Late Stone Age archaeological studies.

Ó 2014 WILEY PERIODICALS, INC.

DOI: 10.1002/ajpa.22526 Published online 00 Month 2014 in Wiley Online Library (wileyonlinelibrary.com).

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J.D. IRISH

Schlebusch et al., 2012; Barbieri et al., 2013). That is, a population once spread throughout southern and eastern Africa is the likely ancient source from which Terminal Pleistocene/Early Holocene South African ancestors of the local Khoesan (Morris, 2002, 2003; Stynder et al., 2007) and other sub-Saharan peoples are descended; however, this diversification event occurred earlier than once thought, i.e., >30,000 years ago (Pickrell et al., 2012; Schlebusch et al., 2012). The concept of “large” vs. “small” Khoesan skeletal remains is also sustained— although again with revised timing. A reduction in cranial (Stynder, 2006, 2007; Stynder et al., 2007) and body size (Sealy and Pfeiffer, 2000; Pfeiffer and Sealy, 2006) is documented, but it occurred more recently, i.e., >4,000 BP, than 12,000–10,000 BP; moreover, a return to pre4000 BP levels occurred by 2000 BP. Finally, the aforementioned initiation of differentiation between the San and Khoekhoe is supported to some extent as well, though the timing was again revised to when pastoralism was first introduced some 2,000 years ago (Deacon and Deacon, 1999; Collins and Burns, 2007; Stynder, 2007, 2009; Stynder et al., 2007). And obvious intergroup skeletal and other variation is not apparent until historic times (e.g., Irish, 1993, 1997; Collins and Burns, 2007). Inherent in many of the preceding studies is a presumption of South African population continuity during much of the Holocene (also Deacon and Deacon, 1999; Mitchell, 2002), contra old arguments for migration and discontinuity in (Stynder et al., 2007). For example, the reason(s) has not been determined with certainty (Pfeiffer and Sealy, 2006), but environmental and cultural factors may account for skeletal size variation between the early (here, >4,000 BP) and middle Holocene (4,000–2,000 BP) (Sealy, 2006; Stynder et al., 2007); however, are other explanations possible? Similarly, diet and lifestyle differences between foragers and the “new” late Holocene (4,000, 4,000–>2,000, and 9,600 to 125 nonredundant discrete crown, root, and osseous oral traits. By nonredundant, it is meant that in the case of bilateral expression, both antimeres were recorded and, allowing for asymmetry, the side with the greatest expression was counted (Turner and Scott, 1977). Alternate approaches, e.g., left side only, etc., are possible American Journal of Physical Anthropology

(see discussion in Irish, 2005), but the aim is to identify the trait’s maximum genetic potential in each individual (Turner, 1985; Turner et al., 1991). Thirty-six of these traits (see list in Table 2) used by the author in prior African dental studies (Irish, 1993, 1997, 2005, 2006, etc.) were employed for the following quantitative analyses. All except UI1 midline diastema (Irish, 1993) are part of the Arizona State University Dental Anthropology System (ASUDAS) (Turner et al., 1991; Scott and Turner, 1997). Reasons for selecting these traits are many (Irish, 1993, 1988, 2005, 2006); in brief they can be observed despite slight to moderate attrition (or are unaffected by it with root and osseous traits), have minimal inter- and intra-observer error rates in recording, are simple to identify, and represent all morphogenetic fields; however, of greater importance, they have a very high genetic component in expression (Scott, 1973; Larsen, 1997; Scott and Turner, 1997; Rightmire, 1999; Martinon-Torres et al., 2007) and are evolutionarily conservative—making them excellent markers for biodistance analyses (Larsen, 1997). Another benefit is the general absence of sexual dimorphism (Scott 1973, 1980; Smith and Shegev, 1988; Bermudez de Castro, 1989; Hanihara, 1992; Irish, 1993), which allows pooling of the sexes for maximum sample sizes. Turner et al. (1991) and Scott and Turner (1997) provide a full description of the ASUDAS.

Quantitative analyses The first step in analysis was to dichotomize all of the rank-scale ASUDAS traits into categories of present or absent. Trait dichotomization is based on their appraised morphological thresholds (Haeussler et al., 1988), as evaluated by Scott (1973), Nichol (1990), and others using a standard procedure (Turner, 1985, 1987; Irish, 1993). This step facilitates tabulation of trait frequencies and is required before data are compared using the mean measure of divergence statistic (MMD) (Berry and Berry, 1967; Sjïvold, 1973, 1977; Green and Suchey, 1976; Harris and Sjïvold, 2004; Irish, 2010). The second step is, by using the MMD, to identify intersample dental phenetic affinities. This statistic measures dissimilarity between sample pairs; low values are indicative of similarity and vice versa. The formula contains the Freeman and Tukey angular transformation to correct for low (0.95) trait frequencies and small sample sizes (n  10) (Sjïvold, 1973, 1977; Green and Suchey, 1976). To determine if samples differ significantly, each MMD value is compared to its standard deviation (SD). If the MMD > 2 X SD, then the null hypothesis of P1 5 P2 (where P 5 sample population) is rejected at the 0.025 level. The MMD and standard deviation formulae, rationale for determining significance, and other methodological details are presented in Sjïvold (1977) and Irish (2010). Beyond its effective application in prior studies, some of which are cited here, the MMD is used because it holds several advantages over other distance measures, including its handling of missing data (Irish, 2010). That said, careful trait editing, a key step when using any distance statistic, is of particular importance with the MMD. To begin with, traits having minimal or no “contributory information” can be deleted (Harris and Sjïvold, 2004, p 91). Oftentimes invariant traits are obvious. Otherwise, those that are least likely or, conversely, most liable to drive inter-sample variation can

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KHOESAN DENTAL AFFINITIES TABLE 2. Dental trait percentages (%) and number of individuals scored (n) for the eight South African Holocene samples Samplea

SHLw

SHLs

SHMw

SHMs

SHE

MAT

KAK

RRI

0.00 45 64.71 17 26.53 49 0.00 9 0.00 22 0.00 17 25.00 12 33.33 9 0.00 7 97.56 41 35.29 17 44.44 18 3.03 33 0.00 39 45.45 44 66.67 21 2.22 45 0.00 40 0.00 52 4.08 49 82.14 28 60.00 10 0.00 48 78.05 41 6.38 47 0.00 27 94.44 36 13.33 15 0.00 14 7.14 14 13.89 36 14.29 42 0.00 40 0.00 31 88.24

5.00 20 66.67 9 8.33 24 33.33 6 0.00 9 16.67 6 20.00 5 66.67 3 0.00 1 100.00 15 11.11 9 25.00 8 0.00 12 0.00 15 72.22 18 88.89 18 0.00 23 0.00 13 12.00 25 15.00 20 66.67 6 100.00 4 0.00 18 66.67 15 11.11 18 0.00 9 100.00 12 33.33 3 0.00 4 0.00 5 30.00 10 5.88 17 0.00 18 0.00 11 85.71

10.34 58 61.76 34 16.13 62 9.52 21 2.94 34 3.45 29 36.00 25 33.33 24 26.09 23 94.34 53 46.43 28 31.03 29 0.00 29 0.00 58 15.22 46 53.85 26 6.45 62 0.00 42 10.77 65 6.45 62 96.97 33 68.00 25 1.79 56 76.00 50 3.51 57 0.00 38 97.92 48 23.08 26 3.45 29 7.41 27 11.63 43 2.17 46 2.04 49 0.00 28 90.91

3.33 30 50.00 24 19.35 31 5.56 18 0.00 25 0.00 14 7.69 13 40.00 15 9.09 11 93.75 32 31.58 19 21.05 19 0.00 18 2.78 36 33.33 30 66.67 18 5.26 38 0.00 26 11.43 35 8.57 35 80.00 15 76.47 17 3.13 32 82.76 29 16.13 31 8.33 24 100.00 27 21.05 19 0.00 18 25.00 20 34.62 26 4.17 24 0.00 26 0.00 16 90.00

4.00 25 80.00 15 3.85 26 22.22 9 0.00 13 0.00 10 22.22 9 55.56 9 0.00 3 91.67 24 28.57 14 18.18 11 0.00 18 0.00 26 33.33 27 78.95 19 17.24 29 0.00 21 6.45 31 17.86 28 92.86 14 75.00 8 0.00 28 59.09 22 0.00 26 0.00 13 100.00 17 11.11 9 0.00 10 9.09 11 30.00 20 23.53 17 0.00 21 0.00 14 71.43

3.23 31 88.89 18 6.67 30 44.44 9 0.00 16 0.00 14 21.43 14 53.33 15 23.08 13 100.00 27 52.17 23 32.00 25 0.00 17 0.00 24 56.67 30 81.82 22 14.63 41 0.00 36 5.88 34 12.50 32 58.33 24 71.43 21 4.44 45 64.52 31 2.27 44 6.90 29 96.43 28 20.00 20 0.00 22 6.06 33 28.13 32 23.08 39 0.00 38 0.00 28 100.00

5.41 37 60.00 30 2.04 49 14.81 27 0.00 34 8.00 25 19.23 26 20.00 30 9.09 22 93.18 44 5.88 34 18.75 32 0.00 43 0.00 42 52.78 36 65.52 29 3.51 57 0.00 50 1.69 59 7.50 40 79.31 29 50.00 14 0.00 51 76.74 43 6.00 50 9.09 33 82.93 41 13.64 22 0.00 24 0.00 37 12.20 41 3.03 33 0.00 39 0.00 38 89.19

7.14 42 54.84 31 7.69 52 16.00 25 0.00 30 3.70 27 42.31 26 33.33 27 18.18 22 95.35 43 20.83 24 15.00 20 2.86 35 0.00 53 43.33 30 83.33 18 0.00 57 0.00 38 6.78 59 5.88 51 76.67 30 68.42 19 1.89 53 65.91 44 5.77 52 8.33 24 96.55 29 32.00 25 0.00 24 11.76 17 20.51 39 5.71 35 0.00 34 0.00 26 80.95

b

1) 2) 3) 4) 5) 6) 7) 8) 9) 10) 11) 12) 13) 14) 15) 16) 17) 18) 19) 20) 21) 22) 23) 24) 25) 26) 27) 28) 29) 30) 31) 32) 33) 34) 35)

Trait Winging UI1 (15ASU 1) Labial curvature UI1 (15ASU 2–4) Palatine torus (15ASU 2–3) Shoveling UI1 (15ASU 2–6) Double shoveling UI1 (15ASU 2–6) Interruption groove UI2 (15ASU 1) Tuberculum dentale UI2 (15ASU 2–6) Bushman canine UC (15ASU 1–3) Distal accessory ridge UC (15ASU 2–5) Hypocone UM2 (15ASU 3–5) Cusp 5 UM1 (15ASU 2–5) Carabelli’s trait UM1 (15ASU 2–7) Parastyle UM3 (15ASU 1–5) Enamel extension UM1 (15ASU 1–3) Root number UP1 (15ASU 21) Root number UM2 (15ASU 31) Peg-reduced UI2 (15ASU P or R) Odontome P1-P2 (15ASU 1) Congenital absence UM3 (15ASU 2) Midline diastema UI1 (10.5 mm) Lingual cusp LP2 (15ASU 2–9) Anterior fovea LM1 (15ASU 2–4) Mandibular torus (15ASU 2–3) Groove pattern LM2 (15ASU Y) Rocker jaw (15ASU 1–2) Cusp number LM1 (15ASU 61) Cusp number LM2 (15ASU 51) Deflecting wrinkle LM1 (15ASU 2–3) C1-C2 crest LM1 (15ASU 1) Protostylid LM1 (15ASU 1–6) Cusp 7 LM1 (15ASU 2–4) Tome’s root LP1 (15ASU 3–5) Root number LC (15ASU 21) Root number LM1 (15ASU 31) Root number LM2

% n % n % n % n % n % n % n % n % n % n % n % n % n % n % n % n % n % n % n % n % n % n % n % n % n % n % n % n % n % n % n % n % n % n %

American Journal of Physical Anthropology

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J.D. IRISH TABLE 2. Continued a

Sample 36)

(15ASU 21) Torsomolar angle LM3 (15ASU 1)

n % n

SHLw

SHLs

SHMw

SHMs

SHE

MAT

KAK

RRI

34 13.64 44

14 6.25 16

33 2.17 46

20 4.76 21

14 3.85 26

29 7.41 27

37 2.17 46

21 9.76 41

a SHLw 5 South African Late Holocene (West), SHLs 5 South African Late Holocene (South), SHMw 5 South African Middle Holocene (West), SHMs 5 South African Middle Holocene (South), SHE 5 South African Early Holocene, MAT 5 Matjes River Rockshelter, KAK 5 Kakamas, RRI 5 Riet River (see text for sample details). b ASU rank-scale trait breakpoints from Irish (1993, 1997, 1998a, b, 2005, 2006) and Scott and Turner (1997).

TABLE 3. MMD distance matrix for 36 traits among the eight South African Holocene samples Samplesa

SHLw

SHLs

SHMw

SHMs

SHE

Late Holocene West Late Holocene South Mid Holocene West Mid Holocene South Early Holocene Matjes River

0.000 0.000 0.012 0.000 0.000 0.044

0.000 0.019 0.000 0.000 0.000

0.000 0.019 0.000 0.070

0.000 0.000 0.033

0.000 0.000

0.000

Kakamas Riet River

0.018 0.001

0.000 0.000

0.054 0.015

0.032 0.000

0.017 0.000

0.073 0.029

MAT

KAK

RRI

0.000 0.000

0.000

a

See Table 1 and text for sample details. Underlined values indicate significant difference at 0.025 level.

be identified quantitatively; in earlier studies correspondence analysis (Irish, 2005, 2006) and principal components analysis (PCA) (Irish and Guatelli-Steinberg, 2003) were used for this purpose. In the present study trait percentages were compared with PCA. Next, it is recommended that intersample distances be based on as many traits as possible; however, these traits should not be highly correlated with one another, as differential weighting of the underlying dimensions may render results inaccurate (Sjïvold, 1977). Between-trait correlation was assessed by submitting the rank-scale ASUDAS data to the Kendall’s tau-b correlation coefficient. The third step in analysis involves presentation of the intersample variation. In addition to MMD distance matrices, an effective and largely unbiased way to illustrate sample affinities is multidimensional scaling (MDS) (Kruskal and Wish, 1978). Interval-level MDS in SPSS 20.0 Procedure Alscal was used to produce threedimensional spatial representations of the samples.

RESULTS Table 2 presents the percentages of individuals expressing each trait and the total number scored. The ASUDAS presence/absence dichotomies are parenthetically listed under each trait name. Very small sample sizes adversely impact a number of traits; the SHLs and, to a lesser degree, SHE samples are particularly affected (e.g., distal accessory ridge UC). Needless to say, such data likely do not adequately characterize the population from which they come, so should be interpreted with caution and addressed during the trait editing process. Missing and other data issues aside, a full 36-trait MMD comparison was conducted to move beyond qualitative inspection of individual trait frequencies and gain an initial impression of inter-sample affinities. The resulting distance matrix is provided in Table 3. Despite American Journal of Physical Anthropology

notable variation among several individual traits across samples (Table 2), including shoveling UI1 (range of 0– 44%), root number UP1 (15–72%), and protostylid LM1 (0–25%), overall dental homogeneity is evident as just three sample pairs are significantly different at the 0.025 alpha level (KAK/MAT, KAK/SHMw, and MAT/ SHMw). The MMD has been shown to be a very robust statistic, in that even problematic traits (numerous missing data, highly correlated, invariant) can yield plausible results (see Irish, 2010). Nonetheless, trait editing was undertaken as described. First, all patently noncontributory traits were deleted, including: double shoveling UI1 (0–3% across samples), hypocone UM2 (92–100%), parastyle UM3 (0–3%), enamel extension UM1 (0–3%), odontome P1-P2 (0%), C1-C2 crest LM1 (0–3%), root number LC (0–2%), and root number LM1 (0%). This initial round of editing reduced the number of traits to 28. Second, these percent data were submitted to PCA to identify additional, largely non-contributory traits in seven of the eight samples; SHLs was excluded from this phase of editing after determining that its very small sample sizes and nonrepresentative frequencies for some traits artificially inflated several of the resultant loadings. Six components with eigenvalues >2.0 were obtained that account for 100% of the total variance. However, inspection of the accompanying scree plot (not shown) suggests that the first three components accounting for 65% of the variance are most important; unrotated loadings for these components are listed in Table 4. Traits with strongly positive or negative values (>j0.5j) drive most of the intersample variation, as illustrated in a graph of group component scores (Fig. 2). For Comp 1, very strong (>0.7) positive loadings for labial curvature UI1, shoveling UI1, Bushman canine, peg-reduced UI2, midline diastema UI1, anterior fovea LM1, cusp 7 LM1, and Tome’s root LP2 are most responsible for pushing

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KHOESAN DENTAL AFFINITIES TABLE 4. Component loadings, eigenvalues, and variance explained for seven South African Holocene samples Trait Number

Comp 1

Comp 2

Comp 3

1* 2* 3* 4* 6* 7 8* 9 11 12* 15* 16* 17* 19* 20* 21 22* 23 24* 25* 26* 27* 28* 30* 31* 32* 35 36* Eigenvalue Variance (%) Total Variance

20.273 0.807 20.297 0.737 20.694 20.180 0.979 20.004 0.526 20.029 0.134 0.644 0.878 0.200 0.840 20.313 0.700 0.416 20.736 20.423 20.173 0.584 20.150 0.128 0.722 0.877 20.111 0.033 8.252 29.471 29.471

0.233 20.453 0.541 20.328 20.426 20.086 0.159 0.293 0.431 20.011 20.653 20.287 20.135 0.843 20.170 0.217 0.685 0.508 0.388 0.604 20.021 0.720 0.504 0.862 0.401 20.354 0.120 20.070 5.524 19.729 49.200

0.755 20.059 20.726 0.474 0.556 0.352 20.099 0.695 20.194 20.709 20.004 0.223 0.013 0.424 0.125 20.176 0.054 0.369 20.316 20.153 0.567 20.146 0.599 20.105 0.019 20.311 0.056 20.533 4.428 15.816 65.016

a

The 22 final traits used for MMD analysis after editing (see Table 2) Boldface numbers indicate “strong” loadings (i.e., > j.5j)

groove UI2 and Y-groove pattern LM2 occur at a high rate in samples near the other end of the x-axis (e.g., KAK). Key traits were also identified along the y- (Comp 2) and z-axes (Comp 3). As a result, tuberculum dentale UI2, lingual cusp LP2, and root number LM2 were deleted. Subsequent varimax rotation, which maximizes differences between large and small loadings, served to reinforce these trait choices; it yielded seven components with eigenvalues >1.0 that account for 100% of the total variance (again not shown). Third, several remaining trait-pairs were found to be highly correlated by Kendall’s tau-b: Bushman canine/distal accessory ridge UC (sb 5 0.717), cusp 5 UM1/Carabelli’s UM1 (sb 5 0.704) and mandibular torus/rocker jaw (sb 5 0.738). Thus, in conjunction with their relatively low loadings (Table 4) and very small sample sizes (Table 2), distal accessory ridge UC, cusp 5 UM1, and mandibular torus were dropped. In the end 22 traits, denoted by asterisks in Table 4, were used for the final MMD comparison. The 22-trait MMD distance matrix for all eight samples is presented in Table 5. Overall homogeneity is again indicated. However, the greater emphasis on divergence, after deleting invariant and other largely noncontributory traits, did increase the number of significant differences from three to seven pairs. That is, KAK and MAT are now more distinct—from one another and three other samples each. The MDS solution provides a good representation of the MMD matrix; Kruskal’s stress formula 1 value is 0.071 and the r2 is 0.941. The configuration (Fig. 3) shares some patterning with the PCA graph (Fig. 2), including relative positions of KAK, RRI, SHMw, and MAT; yet phenetic similitude of all late through early Holocene samples is evident, though with some variation along geographic lines. Divergence of MAT and, particularly, KAK is clear—especially when the spikes are reoriented toward the MDS sample centroid (Fig. 4).

DISCUSSION Hypothesis testing

Fig. 2. Three-dimensional scatterplot of the first three components among seven of the eight Khoesan samples for 28 dental traits. Accounts for 65% of the total variance (29.47% on xaxis, 19.73% on y-axis, and 15.8% on z-axis). Methodological details and the sample abbreviations are defined in the text.

samples with high percents of these traits toward the positive end of the x-axis (e.g., MAT, SHE). Similarly, very strong negative loadings (>20.7) for interruption

Based on the 36- and, notably, 22-trait MMD comparisons (Tables 3 and 5) between early Holocene SHE and middle Holocene samples SHMw (MMD 5 0.019) and SHMs (0.009), the first of two South African Holocene peopling hypotheses to be tested cannot be rejected. Given that these distances did not reach the 0.025 alpha level, the null hypothesis stands—there is no significant difference between dental samples from the early (>4,000 BP) and middle Holocene (7,000-year range of these remains. It is also the second most divergent of samples after KAK. Perhaps the MAT sample is not “representative.” However, the site’s inhabitants were shown to have diachronic diet consistency (Sealy and Pfeiffer, 2000), which could speak to temporal continuity and sample viability. Under this assumption, the phenetic divergence is real and another answer is needed. Specifically, stable isotopic differences between skeletal remains at Matjes River Rockshelter and those just 14 km to the east imply a “clear economic separation” (Sealy and Pfeiffer, 2000; Sealy, 2006, p. 569). The reason, according to Sealy (2006, p 580), is that by about

American Journal of Physical Anthropology

KHOESAN DENTAL AFFINITIES 4500 BP, South shore foraging groups occupied geographically demarcated, mutually exclusive territories. In this particular case, a large estuary “too deep and wide to wade across” separated the territories (Sealy, 2006, p. 580). Economic separation could parallel some small, though observable, measure of genetic separation. In any event, MAT is characterized by slightly greater crown and root complexity than all others, including having the highest occurrences of labial curvature UI1, shoveling UI1, cusp 5 UM1, and root number LM2. With exceptions, these and some other mass-additive, highfrequency traits in the sample are ubiquitous in subSaharan Africans (Irish, 1993, 1997; Irish and GuatelliSteinberg, 2003)—a pattern known as “Afridonty” (Irish, 2013, p 288). “Ultra-Afridonty” in MAT and, to a lesser extent the other non-Khoekhoe samples, may parallel “ultra-African” genetic, skeletal, and anthropometric traits that originally prompted some workers to characterize San as the closest living descendants of the Terminal Pleistocene/Early Holocene ancestors (Tobias, 1966, 1972; Mourant, 1983; Nurse et al, 1985). Concerning other MMD distances, MAT is indistinguishable from the early Holocene (SHE) sample, and does not significantly differ from the late Holocene south sample (SHLs); all were recovered from the South coast, which may be suggestive of regional variation.

General indications Of the quantitatively identified inter-sample trends, three stand out based on values in the two MMD matrices and, in particular, MDS illustrations (Figs. 3 and 4): 1) an apparent west-south dichotomy of samples, 2) the divergence of KAK, and 3) the affinity of RRI to all other samples. Each trend is interpreted below. First, a clear separation (Fig. 3), irrespective of age, is seen between samples from the western Cape (SHLw, SHMw) and those wholly (SHLs, SHMs, and MAT) or primarily (SHE) from the South shore. In fact, MDS plotting of all samples roughly emulates geographic locales (Fig. 1); unfortunately, the regional-level provenience of many specimens precludes calculation of MMD and spatial distance correlation. According to Pfeiffer and Sealy (2006), there are some questions regarding the extent to which peoples from the two regions interacted, and previous researchers generally treated them as distinct. Some support for geographic separation may be gleaned from craniometric findings, where differential size and shape, albeit minor, have been reported among early through late Holocene crania between the Southwest and South coasts (Stynder et al., 2007). Assuming the division between dental samples is real, i.e., genetic, then presumed inter-region reproductive isolation may have been driven, as above, by environmental and/or cultural factors. For example, if Sealy’s (2006) idea of coastal territories can account for some measure of inter-group variation on the South coast, then such genetic variation may be increased on an interregional level. Four biomes ranging from desert-like to forest, along with differences in terrain and resources, exist between the West and South-East coasts (Rutherford and Westfall, 1986; Pfeiffer and Sealy, 2006). A potential indicator of cultural variation may be seen in the mortuary practices between regions. In the west, at least during the late Holocene, individuals were buried in isolated graves within sand dunes or rock shelters, whereas multiple burials in rock shelters were the

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norms on the South coast (e.g., Matjes River) (Rightmire, 1978; Pfeiffer and Sealy, 2006; Stynder, 2009). And, of course, Dutch settlers reported population differences along regional and even geographic lines (Inskeep, 1979); such boundaries likely existed well before European contact. Second, KAK is the most divergent of all Khoesan samples. With regard to individual traits, these historic Khoekhoe pastoralists are characterized by slightly less crown complexity than all others, including much lower frequencies of Bushman canine, cusp 5 UM1, and anterior fovea LM1. Such dental patterning is somewhat remindful of Bantu-speaking groups (Irish, 1993). Based on both 36- and 22-trait MMDs, KAK is most akin to the temporally and regionally proximate San from Riet River (RRI), and next closest to late Holocene SHLw and SHLs. It is significantly different from the remaining six samples—all of which date to >2,000 BP. Given the population history of the Khoekhoe (above), these affinities are plausible. Following the (re)appearance of pastoralist Khoekhoe in South Africa some 2,000 years ago—after obtaining livestock (on their own or from Nilo-Saharan- and/or Afroasiatic-speaking groups) locally or from outside the region (Nurse et al., 1985; Excoffier et al., 1987; Deacon and Decon, 1999; G€ uldemann, 2008))—local genetic exchange occurred, mainly San into Khoekhoe (Parkington, 1981; Nurse et al., 1985). Nevertheless, these groups lived mostly apart. Khoekhoe originally tended their livestock on the West to South coasts, while San foraged farther inland. These economic and regional differences are substantiated by archaeological evidence and 16th and 17th century Dutch observations (Inskeep, 1979; Elphick, 1985; Collins and Burns, 2007). San and Khoekhoe maintained a measure of spatial, cultural, and hence genetic distinctiveness for the past 2,000 years (Wilson, 1986). Thus, any phenotypic variation between groups likely resulted from genetic drift (Hiernaux, 1975), adaptation to different environments and/or diet (Parkington, 1981; Nurse et al, 1985), other cultural factors (Holden and Mace, 2003) and, of note, greater Khoekhoe admixture with late arriving “Bantu” and Europeans (Hiernaux, 1975; Mourant, 1983; Nurse et al., 1985; Morris, 1986; Cavalli-Sforza et al., 1994) including the specific Einiqua individuals comprising the KAK sample (Morris, 1992a). Third, unlike KAK, the historic Riet River (RRI) San sample is noticeable for its phenetic similarity to all others—from contemporary Khoekhoe (KAK) to early Holocene (SHE) samples. With the exception of tuberculum dentale UI2 and Carabelli’s trait UM1, its trait frequencies are intermediate to those of all other samples, as indicated by low nonsignificant MMD distances and a central location in both MDS diagrams. The affinity of RRI to KAK likely relates to San and Khoekhoe admixture, in general, and perhaps direct contact between individuals from these two particular samples (above). The affinity of RRI to the other, more ancient samples may be attributed to genetic isolation from non-Khoesan peoples. That is, the San encountered later Bantu and Dutch immigrants; and ethnohistoric and genetic evidence indicates some admixture occurred (Tobias, 1972, Nurse et al., 1985). However, compared to the Khoekhoe, San interacted little with these newcomers (Hiernaux, 1975; Nurse et al., 1985), as substantiated by serological and other genetic study (Mourant, 1983; Nurse et al., 1985; Cavalli-Sforza et al., 1994; Cruciani et al., 2002). American Journal of Physical Anthropology

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J.D. IRISH

In reality, the Bantu, and especially the Dutch, did more to eradicate the San than to assimilate them (Parkington, 1981; July, 1992).

CONCLUSIONS In sum, determinations of: 1) trait occurrence, 2) the most influential traits, and 3) intersample phenetic distances provide a comprehensive dental description to help further define the Khoesan peoples of South Africa. Based on analyses of six prehistoric samples, overall temporal and spatial homogeneity of early-through-late Holocene peoples is suggested, in agreement with previous archaeological and, more recent, bioarchaeological findings. For the most part, these six samples are characterized by similar expressions of complex, massadditive crown and root traits previously shown to occur, though to a lesser degree, in all sub-Saharan populations. As such, the variation reported in cranial and post-cranial size before and after about 4000 BP is indeed likely to have been related to cultural and environmental phenomena that would affect growth, rather than population replacement or substantial gene flow. As noted, these phenomena are thought to include increased population size, sedentism, and dietary stress. Likewise, with one exception, no dental samples older than 2000 BP were found to differ significantly from those after that time. Thus, in agreement with other evidence, the introduction of pastoralism and other culturerelated factors by 2000 BP was not, apparently, accompanied by noticeable extra-region genetic influence. The one sample exception, i.e., Matjes River Rockshelter, was reported elsewhere to have a different stable isotopic signature than nearby groups, perhaps relating to an hypothesized concept of geographically demarcated, mutually exclusive territories. As suggested here, such demarcation, or other unspecified cultural and environmental variables, may have prompted low-level reproductive isolation to explain the dental divergence. Perhaps the obvious MDS division between early-to-late Holocene samples from the western and southern Cape coasts is related to such an explanation as well, though at an inter-regional level. Finally, the historic Riet River San sample appears similar to all others, while that of the Kakamas Khoekhoe is distant. The results are concordant at a broad level with known population history, in that the San interacted little with immigrant Bantuand European groups relative to the Khoekhoe. Future dental comparisons of these various groups will provide additional detail. Beyond this relatively recent occurrence, the indigenous peoples of South Africa, the Khoesan, reveal notable homogeneity and a high level of phenetic and, hence, population continuity throughout the Holocene.

ACKNOWLEDGMENTS The author thanks the following individuals for granting access to the skeletal collections curated at their respective institutions: James S. Brink and Sharon Holt from the National Museum in Bloemfontein, David Morris at the McGregor Museum in Kimberly, Sven Ouzman of the Iziko South African Museum in Cape Town, and Alan Morris in the Department of Human Biology, University of Cape Town. Many other wonderful folks at these places helped out as well. Lastly, the author is especially indebted to Alan Morris for answering all of the many questions about sample composition, and for American Journal of Physical Anthropology

ably playing the part of tour guide (along with his wife Liz) during the time there.

LITERATURE CITED Afolayan F. 2000. Bantu expansion and its consequences. In: Falola T, editor. Africa: African history before 1885, Vol. 1. Durham, North Carolina: Carolina Academic Press. p 111– 136. Barbieri C, Vicente M, Rocha J, Mpoloka SW, Stoneking M, Pakendorf B. 2013. Ancient substructure in early mtDNA lineages of southern Africa. Am J Hum Genet 92:285–292. Bermudez de Castro JM. 1989. The Carabelli trait in human prehistoric populations of the Canary Islands. Hum Biol 61: 117–131. Berry AC, Berry RJ. 1967. Epigenetic variation in the human cranium. J Anat 101:361–379. Br€ auer G. 1978. The morphological differentiation of anatomically modern man in Africa with some regard to recent finds from East Africa. Z Morphol Anthropol 69:266–292. Br€ auer G. 1984. A craniological approach to the origin of anatomically modern Homo sapiens in Africa and implications for the appearance of modern Europeans.In: Smith FH, Spencer F, editors. The origins of modern humans: a world survey of the fossil evidence. New York: Alan R. Liss. p 327–410. Br€ auer G, Rosing FW. 1989. Human biological history in southern Africa. Rassengeschichte der Menschheit 13:6–137. Brothwell DR. 1963. Evidence of early population change in central and southern Africa: doubts and problems. Man 132: 101–104. Cavalli-Sforza LL, Menozzi P, Piazza A. 1994. The history and geography of human genes, Abridged Paperback Edition. Princeton: Princeton University Press. Clark JD. 1970. The prehistory of Africa. New York: Praeger Publishers. Collins R, Burns J. 2007. A history of sub-Saharan Africa. Cambridge: University of Cambridge Press. Cruciani F, Santolamazza P, Peidong S, Macaulay V, Moral P, Olckers A, Mondiano D, Holmes S, Destro-Bisol G, Coia V, Wallace DC, Oefner PJ, Torroni A, Cavalli-Sforza LL, Scozzari R, Underhill PA. 2002. A back migration from Asia to sub-Saharan Africa is supported by high-resolution analysis of human Y-chromosome haplotypes. Am J Hum Genet 70: 1197–1214. de Villiers H, Wilson M. 1982. Human burials from Byneskranskop, Bredasdorp district, Cape Province, South Africa. Ann S Afr Mus 88:205–248. Deacon HJ. 1984. Later Stone Age people and their descendants in southern Africa.In: Klein RG, editor. Southern African prehistory and palaeoenvironments. Rotterdam: Balkema. p 221– 328. Deacon HJ, Deacon J. 1999. Human beginnings in South Africa: uncovering the secrets of the Stone Age. Walnut Creek, CA: Altamira Press. Deacon HJ, Lancaster N. 1988. Late Quaternary paleoenvironments of southern Africa. Oxford: Clarendon Press. Denbow JR, Wilsem EN. 1986. Advent and course of pastoralism in the Kalahari. Science 234:1509–1515. Dreyer TF, Meiring AJD. 1937. A preliminary report on an expedition to collect old Hottentot skulls. Soologie Navorsing van die Nasionale Museum. Bloemfontein 1:81–88. Ehret C. 1984. Historical/linguistic evidence for early African food production. In: Clark JD, Brandt SA, editors. From hunters to farmers. The causes and consequences of food production in Africa. Berkeley: University of California Press. p 26– 35. Ehret C, Posnansky M. 1982. Eastern and southern Africa overview.In: Ehret C, Posnansky M, editors. The archaeology and linguistic reconstruction of African history. Berkeley: University of California Press. p 99–103. Elphick R. 1985. Khoikhoi and the founding of white South Africa. Johannesburg: Raven Press.

KHOESAN DENTAL AFFINITIES Excoffier L, Pellegrini B, Sanchez-Mazas A, Simon C, Langaney A. 1987. Genetics and history of sub-Saharan Africa. Yrbk Phys Anthropol 30:151–194. Green R, Suchey J. 1976. The use of inverse sine transformation in the analysis of non-metrical data. Am J Phys Anthropol 45:61–68. G€ uldemann T. 2008. A linguist’s view: Khoe-Kwadi speakers as the earliest food-producers of southern Africa. S Afr Humanit 20:93–132. Haeussler AM, Turner CG II, Irish JD. 1988. Concordance of American and Soviet methods in dental anthropology. Am J Phys Anthropol 75:218. Hanihara T. 1992. Dental and cranial affinities among populations of East Asia and the Pacific: The basic populations in East Asia, IV. Am J Phys Anthropol 88:163–182. Harris EF, Sjïvold T. 2004. Calculation of Smith’s mean measure of divergence for intergroup comparisons using nonmetric data. Dental Anthropol 17:83–93. Hausman AJ. 1980. Holocene human evolution in southern Africa: the biocultural development of the Khoisan. Ph.D. Thesis, State University of New York, Binghamton. Hiernaux J. 1975. The people of Africa. New York: Charles Scribner’s Sons. Holden CJ, Mace R. 2003. Spread of cattle led to the loss of matrilineal descent in Africa: a coevolutionary analysis. R Soc 270:2425–2433. Humphreys AJB. 1972. The Type R settlements in the context of the later prehistory and early history of the Riet River Valley. MSc. Dissertation, University of Cape Town. Inskeep RR. 1979. The peopling of southern Africa. New York: Barnes and Noble Publishers. Irish JD. 1993. Biological affinities of late Pleistocene through modern African aboriginal populations: The dental evidence. Ph.D. Dissertation, Arizona State University, Tempe. Irish JD. 1997. Characteristic high- and low-frequency dental traits in Sub-Saharan African populations. Am J Phys Anthropol 102:455–467. Irish JD. 2005. Population continuity versus discontinuity revisited: dental affinities among Late Paleolithic through Christian era Nubians. Am J Phys Anthropol 128:520–535. Irish JD. 2006. Who were the ancient Egyptians? Dental affinities among Neolithic through post-dynastic peoples. Am J Phys Anthropol 129:529–543. Irish JD. 2010. The mean measure of divergence (MMD): its utility in model-free and model-bound analyses relative to the Mahalanobis D2 distance for nonmetric traits. Am J Hum Biol 22:378–395. Irish JD. 2013. Afridonty: the sub-Saharan African dental complex revisited.In: Scott GR, Irish JD, editors. Anthropological perspectives on tooth morphology: genetics, evolution, variation. Cambridge: Cambridge University Press. p 278–295. Irish JD, Guatelli-Steinberg D. 2003. Ancient teeth and modern human origins: an expanded comparison of African PlioPleistocene and recent world dental samples. J Hum Evol 45: 113–144. July RW. 1992. A history of the African people. Prospect Heights, IL: Waveland Press. Kruskal JB, Wish M. 1978. Multidimensional scaling. Beverly Hills, CA: Sage Publications. L’Abbe EN, Loots M, Keough N. 2008. The Matjes river rock shelter: a description of the skeletal assemblage. S Afr Archaeol Bull 63:61–68. Larsen CS. 1997. Bioarchaeology. Cambridge: Cambridge University Press. Martinon-Torres M, Bermudez de Castro J, Gomez-Robles A, Arsuaga J, Carbonell E, Lordkipanidze D, Manzi G, Margvelashvili A. 2007. Dental evidence on the hominin dispersals during the Pleistocene. Proc Natl Acad Sci USA 104: 13279–13282. Mitchell P. 2002. The archaeology of southern Africa. Cambridge: Cambridge University Press. Morris AG. 1986. Khoi and San Craniology: a re-evaluation of the osteological reference samples.In: Singer R, Lundy JK, editors. Variation, culture and evolution in African popula-

11

tions. Johannesburg: Witwatersrand University Press. p 1– 12. Morris AG. 1992a. The skeletons of contact: a study of protohistoric burials from the lower Orange River Valley, South Africa. Johannesburg: Witwatersrand University Press. Morris AG. 1992b. A master catalogue: Holocene human skeletons from South Africa. Johannesburg: Witwatersrand University Press. Morris AG. 2002. Isolation and the origin of the Khoisan: late Pleistocene and early Holocene human evolution at the southern end of Africa. Hum Evol 17:105–114. Morris AG. 2003. The myth of the East African “Bushmen”. S Afr Archaeol Bull 58:85–90. Morris AG, Dlamini N, Parker A, Powrie C, Ribot I, Stynder D. 2004/2005. Later Stone Age burials from the Western Cape Province, South Africa, Part 1: Vo€ evlei. Southern African Field Archaeology. 13 and 14: p 19–26. Mourant AE. 1983. Blood relations: blood groups and anthropology. Oxford: Oxford University Press. Nichol CR. 1990. Dental genetics and biological relationships of the Pima Indians of Arizona. Ph.D. Dissertation, Arizona State University, Tempe, AZ. Nurse GT, Weiner JS, Jenkins T. 1985. The peoples of southern Africa and their affinities. Oxford: Clarendon Press. Parkington JE. 1981. Southern Africa: hunters and food-gatherers.In: Mokhtar G, editor. General history of Africa II: Ancient civilizations of Africa. Berkeley: University of California Press. p 639–670. Patrick MK. 1989. An archaeological and anthropological study of the human skeletal remains from Oakhurst Rockshelter, George, Cape Province, Southern Africa, M.A. thesis, University of Cape Town, Cape Town, South Africa. Pfeiffer S, Sealy J. 2006. Body size among Holocene foragers of the Cape Ecozone, Southern Africa. Am J Phys Anthropol 129:1–11. Phillipson DW. 1985. African archaeology. Cambridge: Cambridge University Press. Pickrell JK, Patterson N, Barbieri C, Berthold F, Gerlach L, G€ uldemann T, Kure B, Mpoloka SW, Nakagawa H, Naumann C, Lipson M, Loh P, Lachance J, Mountain J, Bustamante CD, Berger B, Tishkoff SA, Henn BM, Stoneking M, Reich D, Pakendorf B. 2012. The genetic prehistory of southern Africa. Nat Commun 3:1–6. Rightmire GP. 1978. Human skeletal remains from the southern Cape Province and their bearing on the Stone Age prehistory of South Africa. Quat Res 9:219–230. Rightmire GP. 1999. Dental variation and human history. Rev Archaeol 20:1–3. Rutherford MC, Westfall RH. 1986. Biomes of southern Africa— an objective categorization. Mem Bot Surv S Afr 54:1–98. Schlebusch CM, Skoglund P, Sj€ odin P, Gattepaille LM, Hernandez D, Jay F, Li S, De Jongh M, Singleton A, Blum MGB, Soodyall H, Jakobsson M. 2012. Genomic variation in seven Khoe-San groups reveals adaptation and complex African history. Science 338:374–379. Schuster SC, Miller W, Ratan A, Tomsho LP, Giardine B, Kasson LR, Harris RS, Petersen DC, Zhao F, Qi J, Alkan C, Kidd JM, Sun Y, Drautz DI, Bouffard P, Muzny DM, Reid JG, Nazareth LV, Wang Q, Burhans R, Riemer C, Wittekindt NE, Moorjani P, Tindall EA, Danko CG, Teo WS, Buboltz AM, Zhang Z, Ma Q, Oosthuysen A, Steenkamp AW, Oostuisen H, Venter P, Gajewski J, Zhang Y, Pugh BF, Makova KD, Nekrutenko A, Mardis ER, Patterson N, Pringle TH, Chiaromonte F, Mullikin JC, Eichler EE, Hardison RC, Gibbs RA, Harkins TT, Hayes VM. 2010. Complete Khoisan and Bantu genomes from southern Africa. Nature 463:943–947. Scott GR. 1973. Dental morphology: a genetic study of American white families and variation in living Southwest Indians. Ph.D. Dissertation. Arizona State University, Tempe, AZ. Scott GR. 1980. Population variation of Carabelli’s trait. Hum Biol 52:63–78. Scott GR, Turner CG II. 1997. The anthropology of modern human teeth: dental morphology and its variation in recent human populations. Cambridge: Cambridge University Press.

American Journal of Physical Anthropology

12

J.D. IRISH

Scott GR, Yap Potter RH, Noss JF, Dahlberg AA, Dahlberg T. 1983. The dental morphology of Pima Indians. Am J Phys Anthropol 61:13–31. Sealy JC. 1989. Reconstruction of Later Stone Age diets in the south-western Cape, South Africa: evaluation and application of five isotopic and trace element techniques, Ph.D. thesis, University of Cape Town, Cape Town, South Africa. Sealy JC. 2006. Diet, mobility and settlement pattern among Holocene hunter-gatherers in southernmost Africa. Curr Anthropol 47:569–595. Sealy JC, Pfeiffer S. 2000. Diet, body size and landscape use among Holocene people in the southern Cape, South Africa. Curr Anthropol 41:642–655. Sealy JC, van der Merwe NJ. 1988. Social, spatial and chronological patterning in marine food use as determined by d13C measurements of Holocene human skeletons from the southwestern Cape, South Africa. World Archaeol 20:87–102. Sjïvold T. 1973. Occurrence of minor non-metrical variants in the skeleton and their quantitative treatment for population comparisons. Homo 24:204–233. Sjïvold T. 1977. Non-metrical divergence between skeletal populations: the theoretical foundation and biological importance of C.A.B. Smith’s mean measure of divergence. Ossa 4 (Suppl 1):1–133. Smith P, Shegev M. 1988. The dentition of Nubians from Wadi Halfa, Sudan: an evolutionary perspective. J Dent Assoc S Afr 43:539–541. Stow GW. 1910. The native races of South Africa. London: Swan Sonnenschein. Stynder DD. 2006. A quantitative assessment of variation in Holocene Khoesan crania from South Africa’s Western, Southwestern, Southern and Southeastern coasts and coastal forelands. PhD thesis, University of Cape Town. Stynder DD. 2007. A record of human evolution in South Africa. Available at: http://www.biodiversityexplorer.org/mammals/ primates/human_evolution_in_sa-stynder.pdf

American Journal of Physical Anthropology

Stynder DD. 2009. Craniometric evidence for South African Later Stone Age herders and hunter–gatherers being a single biological population. J Archaeol Sci 36:798–806. Stynder DD, Ackermann RR, Sealy JC. 2007. Craniofacial variation and population continuity during the South African Holocene. Am J Phys Anthropol 134:489–500. Sutton JEG. 1981. East Africa before the seventh century.In: Mokhtar G, editor. General history of Africa II: ancient civilizations of Africa. Berkeley: University of California Press. p 568–592. Tobias PV. 1966. The peoples of Africa south of the Sahara.In: Baker PT, Weiner JS, editors. The biology of human adaptability. Oxford: Clarendon Press. p 111–200. Tobias PV. 1972. Recent human biological studies in southern Africa, with special reference to Negros and Khoisans. Trans R Soc S Afr Part 3 40:109–133. Tobias PV. 1974. Biology of the South African Negro. Capetown: University of Witwatersrand. Tobias PV. 1985. History of physical anthropology in southern Africa. Yrbk Phys Anthropol 28:1–52. Turner CG II. 1985. Expression count: a method for calculating morphological dental trait frequencies by using adjustable weighting coefficients. Am J Phys Anthropol 68:263–268. Turner CG II. 1987. Late Pleistocene and Holocene population history of East Asia based on dental variation. Am J Phys Anthropol 73:305–322. Turner CG II, Nichol CR, Scott GR. 1991. Scoring procedures for key morphological traits of the permanent dentition: the Arizona State University dental anthropology system.In: Kelley MA, Larsen CS, editors. Advances in dental anthropology. New York: Wiley-Liss. p 13–32. Turner CG II, Scott GR. 1977. Dentition of Easter Islanders.In: Dahlberg AA, Graber TM, editors. Orofacial growth and development. Hague: Mouton. p 229–249. Wilson ML. 1986. Khoisanosis: the question of separate identities for Khoi and San.In: Singer R, Lundy JK, editors. Variation, culture and evolution in African populations. Johannesburg: Witwatersrand University Press. p 13–25.