22 Dental Anthropology 2019 │ Volume 32 │ Issue 02 A Sub-Continent of Caries: Prevalence and Severity in Early Holocene through Recent Africans Fawn Carter 1* and Joel D. Irish 2 1 Museum of the North, University of Alaska 2 Research Centre in Evolutionary Anthropology and Palaeoecology, Liverpool John Moores University Here we assess how dental caries frequencies differ by time period, sex, environment, and subsistence strategy among a range of populations across sub- Saharan Africa. Severity is also briefly discussed. Carbohydrate intake, adoption of agriculture, and behavioral and biological differences between the sexes and among populations all influence dental decay, so the latter can be highly informative (Turner, 1979; Newbrun, 1982; Larsen, 1997; Lukacs and Largaespada, 2006; Lukacs and Thompson, 2008). Yet, relatively few dental pathol- ogy studies have been conducted within this vast region (Irish, 1993). Those that have, focus largely on qualitative data or are small in spatiotemporal scope (Flower, 1889; Shaw, 1931; Frencken et al., 1986; Morris et al., 1987; Solanki et al., 1991; Sealy et al., 1992; Mackeowen et al., 1995; Steyn et al., 1998; Cleaton-Jones et al., 2000; Ohinata and Steyn, 2001; Pistorius et al., 2002; Steyn, 2003). The pre- sent study is much more comprehensive, covering the sub-continent from 10,000 years ago to present. At this large scale, the trends observed can work to support and/or refute those observed elsewhere in the world. The findings are discussed in terms of diet and other biocultural practices known to affect dental health. The present study focuses on four research questions: 1) How did dental caries frequencies change through time? The samples were divided into Late Stone Age, Iron Age, or Recent. Each period was marked by a major shift in diet as new foods were introduced. 2) Is there a significant difference in caries be- tween the sexes? The literature indicates a global trend for higher frequencies in females, particular- ly with the advent of agriculture (Caselitz, 1998; Lukacs and Largaespada, 2006; Lukacs, 2008; Lukacs and Thompson, 2008; Ferraro and Vieira, 2010). The present results will help test whether the trend holds in sub-Saharan Africa. 3) How do environmental differences affect the dental caries frequencies? Such differences limit what foods are present, so should have an influ- ence. Samples are divided by the ecosystem from ABSTRACT The most recognizable pathological condition of the human oral cavity is, arguably, dental caries. Beyond a direct impact on oral health, caries presence (or absence) provides important data for bioarchaeologists—to help reconstruct the diet of past populations and individuals. This study explores such data in 44 samples (n=2,119 individuals, 33,444 teeth) dating between 10,000 BP and recent times across the African sub-continent. It is, to date, the most extensive investigation of its kind in this part of the world, entailing descriptions and quantitative comparisons of caries by period, environment, sub- sistence strategy and sex. Mann-Whitney U tests and factorial ANOVA results provide expected and some unexpected findings, including: 1) a diachronic increase in caries prevalence across the sub-continent, likely related to diet change from widespread population movement; 2) savanna peoples exhibit more caries than those from other environmental regions; 3) subsistence strategy plays a major role in caries occurrence; and 4) males and females do not evidence significant differences in caries frequencies, but variation does exist in several regional groups. These findings reveal that global trends described by previous researchers often apply, though not always—so it is prudent to consider regions independently. *Correspondence to: Fawn Carter Museum of the North University of Alaska Fairbanks AK fmcarter@alaska.edu Keywords: dental caries, Africa, environment, sex, subsistence 23 Dental Anthropology 2019 │ Volume 32 │ Issue 02 which they were derived: coastal, desert, savanna/ grassland, and tropical rainforest. 4) How does subsistence strategy affect the caries rates? Sub-Saharan Africans used a range of strategies to procure food, including hunting and gathering, pastoralism, and agriculture. Because diet is determined by subsistence strategy there should be an impact. To address this likelihood and place sub-Saharan African peoples in broader spatiotemporal context, samples from the current study are compared to Turner’s (1979) meta- analysis of populations with different subsistence strategies. Materials and Methods Data on caries prevalence, as well as severity in some instances, were collected from 44 samples (n=2,119 individuals; 33,444 teeth, Table 1) throughout the African sub-continent by Irish dur- ing the course of his dental morphological research (1993, 1997). These samples date from ca. 10,000 BP to the 20th century. The location and severity are recorded for each of the carious lesions present. Caries are ranked on a scale of 1 to 4, with 1 being a small pit that does not penetrate the enamel and 4 being pulp perfora- tion (Buikstra and Ubelaker, 1994). Location is des- ignated as mesial, distal, buccal, occlusal, lingual or a combination in the event of large or multiple lesions. Sex was determined as M, M?, ?, F, F? by the second author using standard methods (e.g., Buikstra and Ubelaker, 1994). Only adults (i.e., ≥18 years of age) were included in the analyses. Lukacs’ (1992, 1996) caries index was calculat- ed to adjust for antemortem tooth loss (AMTL): (AMTL) (% teeth with severe caries) + (teeth with caries) (teeth present) + (AMTL) This method takes into account the number of teeth present with pulp exposure (severity level 4) due to dental caries. The present study compares the percentage of teeth with carious lesions; there- fore, results could be skewed if AMTL were not accounted for, since many teeth are removed due to toothache resulting from serious carious lesions or abscesses (Lukacs, 1996). The caries data were compared using three common statistics. First, Mann-Whitney U tests were used to compare the percent of teeth with carious lesions for the four major categories of in- dependent variables (i.e., period, sex, environment, subsistence). Second, factorial ANOVA accounted for significant differences among subsistence strat- egy, environment, time period, between- sex, or any combination of these four on the dependent variable (percentage of teeth with caries per indi- vidual). The null hypothesis of consistency was tested, followed by a series of post hoc tests (i.e., Tukey) to identify significance between all combi- nations of the independent variables. Lastly, the Spearman’s Rho correlation coefficient was used to simply determine any relationship between attri- tion and caries. Higher levels of wear should corre- late with fewer caries because normal attrition wears away the tooth surface before caries can form (Brothwell, 1963; Scott & Turner, 1988; Hill- son, 1996; Caselitz, 1998). Results The Mann-Whitney U (Table 2) and Tukey (Table 3) test results show a statistically significant differ- ence (p<0.05) for each pair of time periods. The factorial ANOVA found time period to be a signifi- cant factor for caries counts with a value of 0.005 (Table 4) Mann-Whitney U (see Table 2), Tukey (see Table 3) and factorial ANOVA (see Table 4) tests show no statistically significant values for caries frequency differences between the sexes. However, the bar graph (Figure 2) does display a general trend of females with more carious lesions—at least for the Late Stone Age (LSA) and Iron Age samples. In the Recent samples males and females have equal percentages; the only significant differ- ence is among pastoralists (not shown). ANOVA (see Table 4) results show that envi- ronment has a significant impact on caries for the LSA (0.000), Recent (0.009), and Combined groups (0.004). The Mann Whitney U (see Table 2) results reveal no significant difference among environ- ments in terms of caries counts for the Iron Age samples, but some differences do exist for LSA and Recent samples. Tukey (see Table 3) results show significant difference only among the LSA samples. Figure 2 illustrates the different counts of affected individuals for each environment category. Not all environmental categories are represented by time period; as such, some effect on results may occur and these should be interpreted with caution. Factorial ANOVA (see Table 4) results suggest that subsistence contributes to caries counts for the Recent samples (0.060) and all periods combined (0.000). Outcomes from the Mann-Whitney U (see Table 2) and Tukey (see Table 3) tests show a dif- ference between hunter/gatherers and pastoralists among the LSA samples (0.043) and hunter/ gatherers and agriculturalists when all periods are 24 Dental Anthropology 2019 │ Volume 32 │ Issue 02 Code Full Name Country Environment Time Period Subsistence n ADR Adrar Bous Niger Savanna Late Stone Age pastoralism 10 CHA Chad Chad Savanna Recent pastoralism 31 CON Congo Congo Tropical Rain Forest Recent agriculture 34 DBI Republic of the Congo Congo Tropical Rain Forest Iron Age agriculture 20 DCB Lower Congo Congo Tropical Rain Forest Recent agriculture 27 DCH Upper Congo Congo Tropical Rain Forest Recent agriculture 24 DCR Democratic Republic of Congo and Ruanda Democratic Republic of the Congo Tropical Rain Forest Recent agriculture 72 ETH Ethiopia Ethiopia Savanna Recent agriculture 40 FVR Fernand Vaz River Fernand Vaz Tropical Rain Forest Iron Age agriculture 50 GAB Gabon Gabon Tropical Rain Forest Recent agriculture 39 GHA Ghana Ghana Tropical Rain Forest/ Savanna Recent agriculture 48 HAY Haya Tanzania Savanna Recent agriculture 51 IBO Ibo Nigeria Tropical Rain Forest/ Savanna Recent agriculture 54 KEN Kenya Kenya and Tanzania Savanna Recent agriculture 96 KHE Holocene Early Kenya Kenya * Late Stone Age hunter/gatherers 80 KHOI Khoikhoi South Africa Desert Recent pastoralism 56 KKU Kikuyu Kenya Savanna Recent agriculture 60 KHL Rumuniti in Vaso Narok Va- lley Kenya * Late Stone Age * 69 MAT Matjes River Cave South Africa Coast Late Stone Age hunter/gatherers 51 NDB Ndebele Savanna Recent pastoralism 38 NGO Ngorongoro Tanzania Savanna Late Stone Age * 26 NGU South Africa South Africa Savanna Recent agriculture 35 NIC Nigeria/Cameroon Nigeria and Cameroon Tropical Rain Forest/ Savanna Recent agriculture 54 NLT Nilotic Kenya and Tanzania Savanna Recent pastoralism 24 PYG Pygmy Congo, Gabon, and Bot- swana Tropical Rain Forest Recent hunter/gatherers 34 SAN San Botswana and South Afri- ca Desert Recent hunter/gatherers 52 SEN Senegambia Senegal and Gambia Tropical Rain Forest/ Savanna Recent agriculture 42 SHO South Africa South Africa * Recent hunter/gatherers 85 SML Shum Laka Cameroon Savanna Late Stone Age hunter/gatherers 10 SOM Somalia Somalia Desert Recent pastoralists 77 SOT Sotho South Africa Savanna Recent agriculture and pastoralism 66 SPH South Africa South Africa * Iron Age hunter/gatherers 70 SWZ Swazi South Africa * Recent agriculture 58 TAN Tanzania and Zanzibar Tanzania Savanna Recent agriculture 45 TEI Taita Kenya Savanna Recent agricutlure 51 TOD Togo and Dahomey Togo and Benin Tropical Rain Forest/ Savanna Recent hunter/gatherers 26 TSW Tswana Botswana and South Afri- ca Desert Recent hunter/gatherers 63 TUK Tukulor Senegambia Savanna Recent agriculture 40 UPB Upemba Valley Democratic Republic of the Congo Tropical Rain Forest Iron Age agriculture 56 VEN Venda South Africa Savanna Recent agriculture 51 WOL Wolmarnstad South Africa Grassland Recent agricutlure 26 XOS Xosa South Africa Savanna Recent agriculture 66 YOR Yoruba Yoruba Tropical Rain Forest/ Savanna Recent agriculture 28 ZUL Zulu South Africa Savanna Recent pastoralism 66 * information not available Table 1. Summary of samples including the current country the sample was collected from, the environment, time period, and subsistence strategy category the sample was found to best fit with, and the number of individuals from each sample. 25 Dental Anthropology 2019 │ Volume 32 │ Issue 02 Significance* Variable Groups LSA Iron Age Recent Combined Time Period LSA & Iron Age n/a n/a n/a 0.003 LSA & Recent n/a n/a n/a <0.001 Iron Age & Recent n/a n/a n/a <0.001 Sex Male & Female 0.113 0.113 0.564 0.803 Environment Desert & Savanna 0.942 n/a 0.016 0.625 Desert & Rainforest 0.127 n/a 0.84 0.771 Desert & Coastal 0.397 n/a n/a 0.206 Savanna & Rainforest <0.001 0.226 0.007 0.842 Savanna & Coastal 0.018 n/a n/a 0.131 Rainforest & Coastal 0.031 n/a n/a 0.162 Subsistence Hunting/Gathering & Pastoralism 0.043 n/a 0.546 <0.001 Hunting/Gathering & Agriculture n/a n/a 0.975 <0.001 Pastoralism & Agriculture n/a 0.51 0.134 0.654 *significant at p<0.050 Table 2. Results of Mann-Whitney U tests Significance* Variable Groups LSA Iron Age Recent Combined Time Period LSA & Iron Age n/a n/a n/a 0.057 LSA & Recent n/a n/a n/a <0.001 Iron Age & Recent n/a n/a n/a 0.041 Sex Male & Female 0.295 0.415 0.327 0.5 Environment Desert & Savanna 0.965 n/a 0.156 0.941 Desert & Rainforest <0.001 n/a 0.538 0.583 Desert & Coastal 0.607 n/a n/a 0.639 Savanna & Rainforest <0.001 n/a 0.682 0.679 Savanna & Coastal 0.255 n/a n/a 0.424 Rainforest & Coastal <0.001 n/a n/a 0.243 Subsistence Hunting/Gathering & Pastoralism n/a n/a 0.323 0.002 Hunting/Gathering & Agriculture n/a n/a 0.752 <0.001 Pastoralism & Agriculture n/a n/a 0.236 0.125 *significant at p<0.050 Table 3. Tukey results Variable LSA Iron Age Re- cent Combined Time Period n/a n/a n/a 0.349 Sex 0.082 0.675 0.708 0.836 Environment <0.001 0.609 0.009 0.004 Subsistence n/a 0.789 0.069 0.037 *significant at p<0.050 Table 4. Factorial ANOVA results Figure 2. Percent of individuals affected by caries for each environment category in LSA, Iron Age, and Re- cent sub-Saharan African samples. See text for details. 26 Dental Anthropology 2019 │ Volume 32 │ Issue 02 combined (0.000). There is no significant difference in caries number between pastoralists and agricul- turalists for any time period. Figure 3 visually rep- resents the differences between subsistence strate- gies by time period. Lastly, the correlation between wear and caries prevalence was calculated using Spearman’s Cor- relation Coefficient. The correlation of 0.012 indi- cates a very weak, yet positive relationship. An insignificant p-value of 0.400 was calculated. Discussion 1) Did caries frequencies change through time? Results show a definite increase in caries rate through time. Many new crops were introduced through time that may have had an impact. Asian sugarcane and bananas appeared as early as the Iron Age and via the Portuguese in the 17th centu- ry (Frencken et al., 1989; Irish and Turner, 1997). Sugarcane has a negative impact on health not only because of high sucrose levels but because of the manner in which it is eaten, which causes severe crown wear (Dreizen & Spies, 1952; Frencken et al., 1989; Irish & Turner, 1997). Bananas and plantains, both a significant crop in central and eastern Africa (Ehret, 2002), are moderately cariogenic due to their sticky and sugary structure (Mundorff- Shrestha et al., 1994; Aurore et al., 2008). Several cariogenic crops from the Americas were also introduced, including maize and cassava (Larsen et al., 1991; Hillson, 1996; Ehret, 2002); most did not become widespread until the 18th century, which may account for the rise in caries between the Iron Age and Recent samples (Ehret, 2002). Overall, these soft, often sticky high carbo- hydrate foods are much more cariogenic than the traditional African diet (Hillson, 2008). 2) Is the rate of caries higher among females than males? All tests suggest that an individual’s sex did not significantly contribute to the caries frequencies; that said, an examination of the bar chart (Figure 1) reveals a general trend for higher frequencies in females. A common explanation for the disparity is that females collect, prepare and consume more cariogenic foods than do males (Mulder, 1992). Other potential causative factors include genetic and hormone differences; all are said to be accentu- ated in agriculturalist groups (Lukacs and Lar- gaespada, 2006; Lukacs, 2008), though this is not evident in the present African samples—for rea- sons we are continuing to investigate. 3) Are there environmental differences in the caries fre- quencies? Observing patterns is difficult because not all envi- ronmental groups are present by time period. In the Iron Age and Recent periods, caries are more prevalent among those on the savanna. Many of them would have relied on grain foods or pastoral- ism, i.e., the latter peoples often trade with agricul- turalists for grains made into sticky porridge (Forde & Jones, 1950; Skinner, 1973). The naturally high cariogenicity of corn and wheat (Dodds, 1960; Okazaki et al., 2013) combined with the sticky na- ture of the grain porridge potentially contributes to higher instances of caries in savanna dwellers. A high caries percentage (23%) occurs in coastal LSA samples. Coastal peoples generally have fewer caries because of grit and fluoride from marine foods (Walker & Erlandson, 1986). Sealy et al. (1992) report similar results with the Oakhurst sample from the Southern Cape. Contradictory to their results with other coast dwellers, where only 2.6% of teeth exhibit caries, 17.7% of teeth from Oakhurst are affected, despite a diet rich in marine resources; the authors state that the explanation for the high rate is the lack of fluoride in local ground water. 4) Does subsistence strategy affect dental health? The results obtained by factorial ANOVA suggests that subsistence strategy is a contributing factor to caries counts when all time periods are combined. No clear pattern is evident in the bar chart (Figure 3), perhaps because not all strategies are present by period. However, the high rate for Recent pastoral- ists is interesting. As noted, pastoralists eat grains plus milk and other animal byproducts (Forde & Figure 3. Percent of individuals affected by caries for each subsistence strategy in LSA, Iron Age, and Recent sub-Saharan African samples. See text for details. 27 Dental Anthropology 2019 │ Volume 32 │ Issue 02 Jones, 1950; Skinner, 1973). As well, many Recent pastoralists are actually agro-pastoralists (Krige & Krige, 1954; Skinner, 1973; Zeleza, 1997). Grain porridge combined with maize apparently had a negative impact on dental health (Larsen et al., 1991; Scherer et al., 2007). Cassava would also be a starch source (Ehret, 2002) that prevents carbohy- drates being cleaned away to give bacteria more time to feed (Lingstrom et al., 1989, Larsen, 1997; Hillson, 2008). A comparable caries percentage is evident in the Recent hunter/gatherers and agriculturalists. Perhaps this similarity is related to the fact that modern hunter-gatherers, like the San, are not lim- ited to this lifestyle as they once were. After the arrival of Europeans, many Khoisan worked on farms, where they ate crop- rather than wild foods (Reader, 1997; July, 1998). Modern pygmies also often rely on agriculturalists for trade (Afolayan, 2000). The increase in domesticated foods appar- ently caused both groups to have caries rates like those of agriculturalists. Relative to Turner’s (1979) analysis of different economies, the sub-Saharan results are comple- mentary. He reports 0.0-5.3% for hunter/gatherers; the sub-Saharan LSA samples fall within this range (2%), but not for recent hunter-gatherers (8%). Most of Turner’s samples are from early archaeo- logical sites, so were generally not influenced by an agricultural diet. Recent hunter-gatherers fall with- in Turner’s range for mixed economies (0.4-10.3%), which is likely a more adequate descriptive catego- ry. Sub-Saharan pastoralists (5-7%) fall within the mixed economy category, and the agriculturalists (4.0-7%) fit Turner’s agriculturalist category (2.3- 26.9%). Finally, caries severity was only recorded in 469 of the total 2119 dentitions; thus, on that basis the Spearman’s Rho value of 0.012, though posi- tive, is only very weakly correlated, i.e., essentially random. These results suggest here that while of interest individually, such data may be less useful in a broader study. Conclusions Statistically significant differences in dental caries frequencies have been observed between time peri- ods, environmental groups, and subsistence strate- gies among 44 sub-Saharan African samples. The introduction of new foods through time, regional specializations, and food collecting strategies have been found to potentially affect dental decay. The results from the current study imply that cultural differences can have major implications for dental health. REFERENCES Afolayan, F. (2000). Bantu expansion and its conse- quences. In Falola T, (Ed.), Africa: volume 1 Afri- can history before 1885 (pp. 111-136). Durham, North Carolina: Carolina Academic Press. Aurore, G., Pafait, B., & Fahrasmane, L. (2008). Ba- nanas, raw materials for making processed food products. Trends in Food Science and Technology, 20(2), 78-91. Buikstra, J.E., & Ubelaker, D.H. (1994). Standards for data collection from human skeletal remains: pro- ceedings of a seminar at the Field Museum of Natu- ral History (Arkansas Archaeological Report Re- search Series). Arkansas: Arkansas Archaeologi- cal Survey. Caselitz P. (1998). Caries: ancient plague of human- kind. In K. Alt, W. Rösing, M. Teschler-Nicola (Eds.), Dental Anthropology: Fundamentals, Limits, and Prospects (pp. 203-225). New York: Springer. Cleaton-Jones, P., Williams, S., & Fatti, P. (2000). Surveillance of primary dentition in Germiston, South Africa, 1981-97. Community of Dentistry and Oral Epidemiology, 28, 267-274. Dodds, M.L. (1960). The cariogenic property of ce- real foods. The Journal of Nutrition, 71, 317-321. Dreizen, S., & Spies ,T.D. (1952). The incidence of dental caries in habitual sugarcane chewers. Journal of the American Dentistry Association, 45,193-200. Ehret, C. (2002). The civilizations of Africa: a history to 1800. Charlottesville: University of Virginia Press. Ferraro, M., & Vieira, A.R. (2010). Explaining gen- der differences in caries: a mulifactorial ap- proach to a multifactorial disease. International Journal of Dentistry doi:10.1155/2010/649643. Flower, W. (1889). Description of two skeletons of Akkus, a Pygmy race from central Africa. The Journal of Anthropological Institute of Great Britain and Ireland, 18, 3-19. Forde, C.D., & Jones, G.I. (1950). Western Africa part III: The Ibo and Ibibio-speaking peoples of south- eastern Nigeria. London: International African Institute. Frencken, J., Manji, F., & Mosha, H. (1986). Dental caries prevalence amongst 12-year-old urban children in East Africa. Community Dentistry and Oral Epidemiology, 14, 94-98. Frencken, J., & Rugarabamu, P., Mulder, J. (1989.) The effect of sugar cane chewing on the devel- opment of dental caries. Journal of Dental Re- search, 68, 1102-1104. Hillson, S. (1989). Teeth. Cambridge: Cambridge University Press. 28 Dental Anthropology 2019 │ Volume 32 │ Issue 02 Hillson, S. (2008). Dental pathology. In M.A. Kat- zenberg & S.R. Saunders (Eds.), Biological An- thropology of the Human Skeleton (pp. 301-340). New Jersey: John Wiley and Sons Inc. Irish, J.D. (1993). Biological affinities of Late Pleisto- cene through modern African aboriginal populations: the dental evidence. Ph.D. Dissertation, Arizona State University, Tempe. Irish, J.D. (1997). Characteristic high- and low- frequency dental traits in sub-Saharan African populations. American Journal of Physical Anthro- pology, 102, 455-467. Irish, J.D., & Turner, C.G. (1997). Brief communica- tion: first evidence of LSAMAT in non-native Americans: historic Senegalese from West Afri- ca. American Journal of Physical Anthropology, 102, 141-146. July, R.W. (1998). A History of the African people. Fifth ed. Long Grove, Illinois: Waveland Press Inc. Krige, J.D., & Krige, E.J. (1954). The Lovedu of the Transvaal. In C.D. Forde (Ed.), African worlds: studies in the cosmological ideas and social values of African peoples (pp. 5-82). London: Oxford Uni- versity Press. Larsen, C.S. (1997). Bioarchaeology: interpreting be- havior from the human skeleton. Cambridge: Cam- bridge University Press. Larsen, C.S., Shavit, R., & Griffin, M.C. (1991). Den- tal caries evidence for dietary change: an ar- chaeological context. In M.A. Kelley & C.S. Larsen (Eds.), Advances in Dental Anthropology (pp. 179-202). New York: Wiley-Liss, Inc. Lingstrom, P., Holm, J., Birkhed, D., & Bjorck, I. (1989). Effects of variously processed starch on pH of human dental plaque. Scandinavian Jour- nal of Dental Research, 97, 92-400. Lukacs, J.R. (1992). Dental paleopathology and ag- ricultural intensification in South Asia: new evi- dence from Bronze Age Harappa. American Jour- nal of Physical Anthropology, 87, 133-150. Lukacs ,J.R. (1996). Sex differences in dental caries rates with the origin of agriculture in South Asia. Current Anthropology, 37, 147-153. Lukacs, J.R. (2008). Fertility and agriculture accen- tuate sex differences in dental caries rates. Cur- rent Anthropology, 46, 901-914. Lukacs, J.R., & Thompson, L. (2008). Dental caries prevalence by sex in prehistory: magnitude and meaning. In J.D. Irish & G.C. Nelson (Eds.), Technique and Application in Dental Anthropology (pp 136-177). Cambridge: Cambridge University Press. Mackeown, J., Cleaton-Jones, P., & Hargreares, J. (1995). Energy intake, dental caries and perio- dontal disease in 11-year-old black children in two regions of southern Africa: KwaZulu and Namibia. Community Dentistry and Oral Epidemi- ology, 23, 182-186. Morris, A.G., Thackeray, A.I., & Thackeray, J.F. (1987). Late Holocene human skeletal remains from Snuifklip, near Vleesbaai, Southern Cape. The South African Archaeological Bulletin, 42, 153- 160. Mulder, M.B. (1992). Demography of pastoralists: preliminary data of the Datoga of Tanzania. Hu- man Ecology, 20, 383-405. Mundorff-Shrestha, S.A., Featherstone, J.D.B., Ei- senberg, A.D., Cowles, E., Curzon, M.E.J., Es- peland, M.A., & Shields, C.P. (1994). Cariogenic potential of foods: II relationship of food com- position, plaque microbial counts, and salivary parameters to caries in the rat model. Caries Re- search, 28,106-115. Newbrun, E. (1982). Sugar and dental caries: A re- view of human studies. Science, 217, 418-423. Ohinata, F., & Steyn, M. (2001). Report on human skeletal remains from a Later Iron Age site at Simunye (Swaziland). The South African Archaeo- logical Bulletin, 56, 57-61. Okazaki, K., Pei-Ying, T., & Kuo-Shyan, L. (2013). Sex difference in oral disease of millet agricul- turalists from the Take-vatan lineage of the re- cent Banun tribe of Taiwan. Anthropological Sci- ence, 121, 105-113. Pistorius, J.C.C., Steyn, M,. & Nienaber, W.C. (2002). Two burials at Malle, a Late Iron Age settlement in the Bankeveld in the North-West Province. The South African Archaeological Bulle- tin, 57, 55-63. Reader, J. (1997). Africa: a biography of the continent Africa. New York: Vintage Books a Division of Random House, Inc. Scherer, A.K., Wright, L.E., & Yoder, C.J. (2007). Bioarchaeological evidence for social and tem- poral differences in diet at Pidras Negras, Gua- temala. Latin American Antiquity, 18, 85-104. Sealy, J.C., Patrick, M.K., Morris, A.G., & Alder, D. (1992). Diet and dental caries among Late Stone Age inhabitants of Cape Province, South Africa. American Journal of Physical Anthropology, 88, 123 -134. Shaw, J.C.M. (1931). The teeth, the bony palate and the mandible in Bantu races of South Africa. London: John Bale, Sons and Danielsson, Limited. Skinner, E.P. (1973). West African economic sys- tems. In E.P. Skinner (Ed.), Peoples and Cultures of Africa: An Anthropological Reader (pp. 205-210). 29 Dental Anthropology 2019 │ Volume 32 │ Issue 02 Garden City, New York: Natural History Press. Solanki, G., Myburgh, N., & Moola, M.H. (1991). Dental caries in black preschool children in Cape Town. Community Dentistry and Oral Epide- miology, 19, 178-179. Steyn, M. (2003). A comparison between pre- and post-colonial health in northern parts of South Africa, a preliminary study. World Archaeology, 35, 276-288. Steyn, M., Miller, S., Nienaber, W.C., & Loots, M. (1998). Late Iron Age gold burials from Thu- lamela (Pafuri Region, Kruger National Park). The South African Archaeological Bulletin, 53, 73- 85. Turner, C.G. (1979). Dental anthropological indica- tions of agriculture among the Jomon people of Central Japan. American Journal of Physical An- thropology, 51, 619-636. Walker, P.L., & Erlandson, J.M. (1986.) Dental evi- dence for prehistoric dietary change on the Northern Channel Islands, California. American Antiquity, 5, 375-383. Zeleza, T. (1997). A modern economic history of Afri- ca: The nineteenth century. V. 1. Nairobi: East Af- rican Educational Publishers Ltd.