The Impact of dental wear on the analysis of morphological affinities based on dental non-metric traits
Main Article Content
Abstract
Dental wear is described as a limitation to dental morphological studies, as it obscures important crown trait features, resulting in significant differences on trait frequencies, an essential component for estimating biodistances. However, the actual impact of dental wear on biological distances still requires further characterization. We explore the impact of dental wear on morphological affinities for Brazilian pre-colonial series in the context of worldwide reference series. Twenty crown traits were scored using the Arizona State University Dental Anthropological System, and dental wear was quantified as an ordinal scale between 1 (no wear) and 8 (crown eroded). Seven crown trait frequencies are significantly associated with dental wear (p<0.05), demonstrating its impact on their analysis. To explore this impact on biodistances, data was divided by wear categories (all teeth, low-wear, moderate/severe wear) and morphological affinities among series was compared through Euclidean distances, Mean Measure of Divergence, and Principal Component Analysis. Results show the impact of wear is only meaningful when a sample contains many wear-biased traits with only moderate/severe wear. We conclude despite the impact of wear on individual trait frequencies, its impact on morphological affinities can be mitigated by including other variables or when comparisons focus only on large-scale biological differences.
References
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Hanihara, T. (2008). Morphological variation of major human populations based on nonmetric dental traits. American Journal of Physical Anthropology, 136(2), 169–182. https://doi.org/10.1002/ajpa.20792
Haydenblit, R. (1996). Dental variation among four pre-Hispanic Mexican populations. American Journal of Physical Anthropology, 100(1), 225–246.
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Hrdli?ka, A. (1921). Further studies of tooth morphology. American Journal of Physical Anthropology, 4(2), 141–176. https://doi.org/10.1002/ajpa.1330040204
Hubbard, A. R., Guatelli-Steinberg, D., & Irish, J. D. (2015). Do nuclear DNA and dental nonmetric data produce similar reconstructions of regional population history? An example from modern coastal Kenya. American Journal of Physical Anthropology, 157(2), 295–304. https://doi.org/10.1002/ajpa.22714
Huffman, M. M. (2014). Biological variation in South America populations using dental non-metric traits: assessment of isolation by time and distance. The Ohio State University.
Irish, J. D., Lillios, K. T., Waterman, A. J., & Silva, A. M. (2017). “Other” possibilities? Assessing regional and extra-regional dental affinities of populations in the Portuguese Estremadura to explore the roots of Iberia’s Late Neolithic-Copper Age. Journal of Archaeological Science: Reports. https://doi.org/10.1016/j.jasrep.2016.12.003
Irish, J. D., Morez, A., Girdland Flink, L., Phillips, E. L. W., & Scott, G. R. (2020). Do dental nonmetric traits actually work as proxies for neutral genomic data? Some answers from continental- and global-level analyses. American Journal of Physical Anthropology. https://doi.org/10.1002/ajpa.24052
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Nichol, C. R., & Turner, C. G. (1986). Intra- and interobserver concordance in classifying dental morphology. American Journal of Physical Anthropology, 69(3), 299–315. https://doi.org/10.1002/ajpa.1330690303
Ortiz, A. (2013). Dental morphological variation among six Pre-Hispanic South American populations with implications for the peopling of the New World. Dental Anthropology, 26(1–2), 20–32.
Powell, J. F. (1995). Dental variation and biological affinity among Middle Holocene human populations in North America. Texas A & M University.
Powell, J. F. (1997). Variação dentária nas Américas: uma visão alternativa. Revista USP, 34, 82–95.
Powell, J. F., & Neves, W. A. (1998). Dental diversity of early New World populations: Taking a bite out of the tripartite model. American Journal of Physical Anthropology, 26, 179–180.
Powell, J. F., & Rose, J. C. (1999). Report on the osteological assessment of the “Kennewick Man” skeleton. In Report on the Nondestructive Examination, Description and Analysis of the Human Remains from Columbia Park, Kennewick, Washington, 1999.
R Core Team. (2020). A language and environment for statistical computing. R Foundation for Statistical Computing. https://www.r-project.org/
Rathmann, H., Kyle, B., Nikita, E., Harvati, K., & Saltini Semerari, G. (2019). Population history of southern Italy during Greek colonization inferred from dental remains. American Journal of Physical Anthropology, 170(4), 519–534. https://doi.org/10.1002/ajpa.23937
Rathmann, H., & Reyes-Centeno, H. (2020). Testing the utility of dental morphological trait combinations for inferring human neutral genetic variation. Proceedings of the National Academy of Sciences, 117(20), 10769 LP – 10777. https://doi.org/10.1073/pnas.1914330117
Rathmann, H., Reyes-centeno, H., Ghirotto, S., Creanza, N., Harvati, K., Hanihara, T., & Harvati, K. (2017). Reconstructing human population history from dental phenotypes. Scientific Reports, 7(1), 12495. https://doi.org/10.1038/s41598-017-12621-y
Scott, G. Richard. (1980). Population Variation of Carabelli’s Trait. Human Biology, 52(1), 63–78. http://www.jstor.org/stable/41463185
Scott, G. Richard, Anta, A., Schomberg, R., & de la Rúa, C. (2013). Basque dental morphology and the “Eurodont” dental pattern. In Anthropological Perspectives on Tooth Morphology. https://doi.org/10.1017/cbo9780511984464.013
Scott, G. Richard, & Irish, J. D. (2013). Anthropological Perspectives on Tooth Morphology: Genetics, Evolution, Variation. In Cambridge Studies in Biological and Evolutionary Anthropology. Cambridge University Press. https://doi.org/DOI: 10.1017/CBO9780511984464
Scott, G. Richard, & Irish, J. D. (2017). Human Tooth Crown and Root Morphology. Cambridge University Press. https://doi.org/10.1017/9781316156629
Scott, G. Richard, Maier, C., & Heim, K. (2016). Identifying and Recording Key Morphological (Nonmetric) Crown and Root Traits. In J. D. Irish & G. R. Scott (Eds.), A Companion to Dental Anthropology (First Edit, pp. 245–264). John Wiley & Sons, Inc. https://doi.org/10.1002/9781118845486.ch17
Scott, G. Richard, Pilloud, M. A., Navega, D., Coelho, J. d’Oliveira, Cunha, E., & Irish, J. D. (2018). rASUDAS: A New Web-Based Application for Estimating Ancestry from Tooth Morphology. Forensic Anthropology, 1(1), 18–31.
Scott, G. Richard, Schmitz, K., Heim, K. N., Paul, K. S., Schomberg, R., & Pilloud, M. A. (2018). Sinodonty, Sundadonty, and the Beringian Standstill model: Issues of timing and migrations into the New World. Quaternary International, 466, 233–246. https://doi.org/https://doi.org/10.1016/j.quaint.2016.04.027
Scott, G. Richard, & Turner II, C. G. (1997). The Anthropology of Modern Human Teeth: Dental Morphology and its Variation in Recent Human Populations. In Cambridge Studies in Biological and Evolutionary Anthropology. Cambridge University Press. https://doi.org/DOI: 10.1017/CBO9781316529843
Smith, B. H. (1984). Patterns of molar wear in hunger-gatherers and agriculturalists. American Journal of Physical Anthropology, 63(1), 39–56. https://doi.org/10.1002/ajpa.1330630107
Stojanowski, C. M., & Johnson, K. M. (2015). Observer error, dental wear, and the inference of new world sundadonty. American Journal of Physical Anthropology, 156(3), 349–362. https://doi.org/10.1002/ajpa.22653
Stojanowski, C. M., Johnson, K. M., & Duncan, W. N. (2013). Geographic patterns of Early Holocene New World dental morphological variation. Dental Anthropology, 26(3), 7–15.
Sutter, R. C. (2005). The prehistoric peopling of South America as inferred from epigenetic dental traits. Andean Past, 7(1), 183–217.
Sutter, R. C. (2009). Prehistoric population dynamics in the Andes. In J. Marcus & P. R. Williams (Eds.), Andean civilization: a tribute to Michael E. Moseley (Monograph, pp. 9–38). UCLA Cotsen Institute of Archaeology Press.
Tang, Y., Horikoshi, M., & Li, W. (2016). ggfortify: unified interface to visualize statistical results of popular R packages. The R Journal, 6(2), 478–489.
Turner II, C. G. (1976). Dental evidence on the origins of the Ainu and Japanese. Science, 193(4256), 911 LP – 913. https://doi.org/10.1126/science.781841
Turner II, C. G. (1989). Teeth and Prehistory in Asia. Scientific American, 260(2), 88–97.
Turner II, C. G. (1990). Major features of Sundadonty and Sinodonty, including suggestions about East Asian microevolution, population history and Late Pleistocene relationships with Australian aboriginals. American Journal of Physical Anthropology, 82(1), 295–317.
Turner II, C. G. (2006). Dental morphology and the population history of the Pacific rim and basin: commentary on Hirofumi Matsumura and Mark J. Hudson. American Journal of Physical Anthropology, 130(4), 455–461. https://doi.org/10.1002/ajpa.20380
Turner II, C. G., Nichol, C. R., & Scott, G. R. (1991). Scoring procedures for key morphological traits of the permanent dentition: The Arizona State University Dental Anthropology System. In M. A. Kelley & C. S. Larsen (Eds.), Advances in Dental Anthropology (pp. 13–31). Wiley-Liss, Inc.
Turner II, C. G., & Scott, G. R. (1977). Dentition of Easter Islanders. In A. A. Dahlberg & T. M. Graber (Eds.), Orofacial growth and development (pp. 229–249). The Hague: Mouton.
Turner II, C. G., & Scott, G. R. (2013). The Dentition of American Indians: Evolutionary Results and Demographic Implications Following Colonization from Siberia. In W. Henke & I. Tattersall (Eds.), Handbook of Paleoanthropology (pp. 1–35). Springer Berlin Heidelberg. https://doi.org/10.1007/978-3-642-27800-6_63-3
Venables, W., & Ripley, B. (2002). Modern Applied Statistics with S (4th ed.). Springer. http://www.stats.ox.ac.uk/pub/MASS4
Wickham, H. (2016). ggplot2: Elegant Graphics for Data Analysis. Springer-Verlag.
Wu, L., & Turner, C. G. (1993). Brief communication: Variation in the frequency and form of the lower permanent molar middle trigonid crest. American Journal of Physical Anthropology, 91(2), 245–248. https://doi.org/10.1002/ajpa.1330910210
Burnett, S. E. (2016). Crown Wear: Identification and Categorization. In J. D. Irish & G. R. Scott (Eds.), A Companion to Dental Anthropology (First Edit, pp. 415–432). John Wiley & Sons, Inc. https://doi.org/doi:10.1002/9781118845486.ch25
Burnett, S. E., Irish, J. D., & Fong, M. R. (2013). Wear’s the problem? Examining the effect of dental wear on studies of crown morphology. In G. R. Scott & J. D. Irish (Eds.), Anthropological perspectives on tooth morphology: genetics, evolution, variation (66th ed., pp. 535–554). Cambridge University Press.
Dahlberg, A. A. (1945). The Changing Dentition of Man. The Journal of the American Dental Association, 32(11), 676–690. https://doi.org/https://doi.org/10.14219/jada.archive.1945.0112
Greenberg, J. H., Turner, C. G., Zegura, S. L., Campbell, L., Fox, J. A., Laughlin, W. S., Szathmary, E. J. E., Weiss, K. M., & Woolford, E. (1986). The Settlement of the Americas: A Comparison of the Linguistic, Dental, and Genetic Evidence [and Comments and Reply]. Current Anthropology, 27(5), 477–497. http://www.jstor.org/stable/2742857
Hanihara, T. (2008). Morphological variation of major human populations based on nonmetric dental traits. American Journal of Physical Anthropology, 136(2), 169–182. https://doi.org/10.1002/ajpa.20792
Haydenblit, R. (1996). Dental variation among four pre-Hispanic Mexican populations. American Journal of Physical Anthropology, 100(1), 225–246.
Hillson, S. (2005). Teeth. In Cambridge Manuals in Archaeology (2nd ed.). Cambridge University Press. https://doi.org/DOI:
Houle, D., Pélabon, C., Wagner, G. P., & Hansen, T. F. (2011). Measurement and Meaning in Biology. The Quarterly Review of Biology, 86(1), 3–34. https://doi.org/10.1086/658408
Hrdli?ka, A. (1920). Shovel?shaped teeth. American Journal of Physical Anthropology, 3(4), 429–465. https://doi.org/10.1002/ajpa.1330030403
Hrdli?ka, A. (1921). Further studies of tooth morphology. American Journal of Physical Anthropology, 4(2), 141–176. https://doi.org/10.1002/ajpa.1330040204
Hubbard, A. R., Guatelli-Steinberg, D., & Irish, J. D. (2015). Do nuclear DNA and dental nonmetric data produce similar reconstructions of regional population history? An example from modern coastal Kenya. American Journal of Physical Anthropology, 157(2), 295–304. https://doi.org/10.1002/ajpa.22714
Huffman, M. M. (2014). Biological variation in South America populations using dental non-metric traits: assessment of isolation by time and distance. The Ohio State University.
Irish, J. D., Lillios, K. T., Waterman, A. J., & Silva, A. M. (2017). “Other” possibilities? Assessing regional and extra-regional dental affinities of populations in the Portuguese Estremadura to explore the roots of Iberia’s Late Neolithic-Copper Age. Journal of Archaeological Science: Reports. https://doi.org/10.1016/j.jasrep.2016.12.003
Irish, J. D., Morez, A., Girdland Flink, L., Phillips, E. L. W., & Scott, G. R. (2020). Do dental nonmetric traits actually work as proxies for neutral genomic data? Some answers from continental- and global-level analyses. American Journal of Physical Anthropology. https://doi.org/10.1002/ajpa.24052
Kaidonis, J. A. (2008). Tooth wear: the view of the anthropologist. Clinical Oral Investigations, 12(Suppl 1), 21–26. https://doi.org/10.1007/s00784-007-0154-8
Kimura, R., Yamaguchi, T., Takeda, M., Kondo, O., Toma, T., Haneji, K., Hanihara, T., Matsukusa, H., Kawamura, S., Maki, K., Osawa, M., Ishida, H., & Oota, H. (2009). A common variation in EDAR is a genetic determinant of shovel-shaped incisors. American Journal of Human Genetics, 85(4), 528–535. https://doi.org/10.1016/j.ajhg.2009.09.006
Lahr, M. M., & Haydenblit, R. (1995). Traces of ancestral morphology in Tierra del Fuego and Patagonia. Ameriacan Journal of Physical Anthropology, 20((Suppl)), 128.
Marado, L. M. (2017). Dental nonmetric trait intraobserver precision: three observations of a large sample. Anthropologischer Anzeiger; Bericht Uber Die Biologisch-Anthropologische Literatur, 74(1), 15–23. https://doi.org/10.1127/anthranz/2017/0686
Nichol, C. R., & Turner, C. G. (1986). Intra- and interobserver concordance in classifying dental morphology. American Journal of Physical Anthropology, 69(3), 299–315. https://doi.org/10.1002/ajpa.1330690303
Ortiz, A. (2013). Dental morphological variation among six Pre-Hispanic South American populations with implications for the peopling of the New World. Dental Anthropology, 26(1–2), 20–32.
Powell, J. F. (1995). Dental variation and biological affinity among Middle Holocene human populations in North America. Texas A & M University.
Powell, J. F. (1997). Variação dentária nas Américas: uma visão alternativa. Revista USP, 34, 82–95.
Powell, J. F., & Neves, W. A. (1998). Dental diversity of early New World populations: Taking a bite out of the tripartite model. American Journal of Physical Anthropology, 26, 179–180.
Powell, J. F., & Rose, J. C. (1999). Report on the osteological assessment of the “Kennewick Man” skeleton. In Report on the Nondestructive Examination, Description and Analysis of the Human Remains from Columbia Park, Kennewick, Washington, 1999.
R Core Team. (2020). A language and environment for statistical computing. R Foundation for Statistical Computing. https://www.r-project.org/
Rathmann, H., Kyle, B., Nikita, E., Harvati, K., & Saltini Semerari, G. (2019). Population history of southern Italy during Greek colonization inferred from dental remains. American Journal of Physical Anthropology, 170(4), 519–534. https://doi.org/10.1002/ajpa.23937
Rathmann, H., & Reyes-Centeno, H. (2020). Testing the utility of dental morphological trait combinations for inferring human neutral genetic variation. Proceedings of the National Academy of Sciences, 117(20), 10769 LP – 10777. https://doi.org/10.1073/pnas.1914330117
Rathmann, H., Reyes-centeno, H., Ghirotto, S., Creanza, N., Harvati, K., Hanihara, T., & Harvati, K. (2017). Reconstructing human population history from dental phenotypes. Scientific Reports, 7(1), 12495. https://doi.org/10.1038/s41598-017-12621-y
Scott, G. Richard. (1980). Population Variation of Carabelli’s Trait. Human Biology, 52(1), 63–78. http://www.jstor.org/stable/41463185
Scott, G. Richard, Anta, A., Schomberg, R., & de la Rúa, C. (2013). Basque dental morphology and the “Eurodont” dental pattern. In Anthropological Perspectives on Tooth Morphology. https://doi.org/10.1017/cbo9780511984464.013
Scott, G. Richard, & Irish, J. D. (2013). Anthropological Perspectives on Tooth Morphology: Genetics, Evolution, Variation. In Cambridge Studies in Biological and Evolutionary Anthropology. Cambridge University Press. https://doi.org/DOI: 10.1017/CBO9780511984464
Scott, G. Richard, & Irish, J. D. (2017). Human Tooth Crown and Root Morphology. Cambridge University Press. https://doi.org/10.1017/9781316156629
Scott, G. Richard, Maier, C., & Heim, K. (2016). Identifying and Recording Key Morphological (Nonmetric) Crown and Root Traits. In J. D. Irish & G. R. Scott (Eds.), A Companion to Dental Anthropology (First Edit, pp. 245–264). John Wiley & Sons, Inc. https://doi.org/10.1002/9781118845486.ch17
Scott, G. Richard, Pilloud, M. A., Navega, D., Coelho, J. d’Oliveira, Cunha, E., & Irish, J. D. (2018). rASUDAS: A New Web-Based Application for Estimating Ancestry from Tooth Morphology. Forensic Anthropology, 1(1), 18–31.
Scott, G. Richard, Schmitz, K., Heim, K. N., Paul, K. S., Schomberg, R., & Pilloud, M. A. (2018). Sinodonty, Sundadonty, and the Beringian Standstill model: Issues of timing and migrations into the New World. Quaternary International, 466, 233–246. https://doi.org/https://doi.org/10.1016/j.quaint.2016.04.027
Scott, G. Richard, & Turner II, C. G. (1997). The Anthropology of Modern Human Teeth: Dental Morphology and its Variation in Recent Human Populations. In Cambridge Studies in Biological and Evolutionary Anthropology. Cambridge University Press. https://doi.org/DOI: 10.1017/CBO9781316529843
Smith, B. H. (1984). Patterns of molar wear in hunger-gatherers and agriculturalists. American Journal of Physical Anthropology, 63(1), 39–56. https://doi.org/10.1002/ajpa.1330630107
Stojanowski, C. M., & Johnson, K. M. (2015). Observer error, dental wear, and the inference of new world sundadonty. American Journal of Physical Anthropology, 156(3), 349–362. https://doi.org/10.1002/ajpa.22653
Stojanowski, C. M., Johnson, K. M., & Duncan, W. N. (2013). Geographic patterns of Early Holocene New World dental morphological variation. Dental Anthropology, 26(3), 7–15.
Sutter, R. C. (2005). The prehistoric peopling of South America as inferred from epigenetic dental traits. Andean Past, 7(1), 183–217.
Sutter, R. C. (2009). Prehistoric population dynamics in the Andes. In J. Marcus & P. R. Williams (Eds.), Andean civilization: a tribute to Michael E. Moseley (Monograph, pp. 9–38). UCLA Cotsen Institute of Archaeology Press.
Tang, Y., Horikoshi, M., & Li, W. (2016). ggfortify: unified interface to visualize statistical results of popular R packages. The R Journal, 6(2), 478–489.
Turner II, C. G. (1976). Dental evidence on the origins of the Ainu and Japanese. Science, 193(4256), 911 LP – 913. https://doi.org/10.1126/science.781841
Turner II, C. G. (1989). Teeth and Prehistory in Asia. Scientific American, 260(2), 88–97.
Turner II, C. G. (1990). Major features of Sundadonty and Sinodonty, including suggestions about East Asian microevolution, population history and Late Pleistocene relationships with Australian aboriginals. American Journal of Physical Anthropology, 82(1), 295–317.
Turner II, C. G. (2006). Dental morphology and the population history of the Pacific rim and basin: commentary on Hirofumi Matsumura and Mark J. Hudson. American Journal of Physical Anthropology, 130(4), 455–461. https://doi.org/10.1002/ajpa.20380
Turner II, C. G., Nichol, C. R., & Scott, G. R. (1991). Scoring procedures for key morphological traits of the permanent dentition: The Arizona State University Dental Anthropology System. In M. A. Kelley & C. S. Larsen (Eds.), Advances in Dental Anthropology (pp. 13–31). Wiley-Liss, Inc.
Turner II, C. G., & Scott, G. R. (1977). Dentition of Easter Islanders. In A. A. Dahlberg & T. M. Graber (Eds.), Orofacial growth and development (pp. 229–249). The Hague: Mouton.
Turner II, C. G., & Scott, G. R. (2013). The Dentition of American Indians: Evolutionary Results and Demographic Implications Following Colonization from Siberia. In W. Henke & I. Tattersall (Eds.), Handbook of Paleoanthropology (pp. 1–35). Springer Berlin Heidelberg. https://doi.org/10.1007/978-3-642-27800-6_63-3
Venables, W., & Ripley, B. (2002). Modern Applied Statistics with S (4th ed.). Springer. http://www.stats.ox.ac.uk/pub/MASS4
Wickham, H. (2016). ggplot2: Elegant Graphics for Data Analysis. Springer-Verlag.
Wu, L., & Turner, C. G. (1993). Brief communication: Variation in the frequency and form of the lower permanent molar middle trigonid crest. American Journal of Physical Anthropology, 91(2), 245–248. https://doi.org/10.1002/ajpa.1330910210
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This work is licensed under a Creative Commons Attribution 4.0 International License.