Periodic Reporting for period 1 - VAPP (Virtual Anthropology of Prehistoric Portugal)
Período documentado: 2020-01-06 hasta 2022-01-05
The primary goal of the Virtual Anthropology of Prehistoric Portugal (VAPP) Project was to document and interpret patterns of external and internal dental morphological variation among prehistoric humans spanning the Upper Paleolithic to Bronze Age of Portugal. We examined the dental morphology of archaeological human teeth to better understand human population dynamics, microevolution, and behavior in Portugal from the Pleistocene to historic periods. We recorded data on external dental morphology (like tooth size and shape) as well as discrete characteristics—variation in cusp and root number, patterning, and relative size among other traits. Together and independently, these data can provide evidence of past human biological affinity and relatedness within and between human populations, as well as signatures of selection on dental morphology related to dietary, masticatory, and behavioral variation.
In addition to the external observations made on teeth that can be viewed with the naked eye or low magnification, we used advanced virtual imaging technologies to explore the morphology that is found beneath the surfaces of teeth. Virtual images were created using non-destructive, x-ray microcomputed tomography (microCT) to obtain high-resolution images of internal dental morphology that could be reconstructed for three-dimensional (3D) analysis of tissue proportions (i.e. the relative amount of enamel, dentin, and pulp), the shape of the enamel-dentin junction (where the enamel and dentin meet), and enamel thickness. These variables provide fine-grained insights into human population dynamics that may not be possible from external morphology (e.g. because tooth wear during life removes relevant cusp morphology) or aspects of selection—such as changes in tissue proportions or enamel thickness—that may correspond to changing diet and food processing technology throughout human evolution.
During the project a large and unique virtual database of archaeological human teeth was amassed that will greatly improve our understanding of human biocultural evolution in Portugal but also provide an important source of comparative material for exploring broader, interregional patterning of dental microevolution and how this reflects human behavior in the past. Not only will this provide more nuanced understanding of population dynamics in the past, but specific dental traits not previously explored from the standpoint of external and internal morphology (e.g. lateral incisor mesial bending) will be more fully understood.
Importantly, the project explored non-destructive means of assessing human population dynamics and behavior that ensures opportunities for future research focused on these finite cultural heritage resources while also providing a virtual record of their current state of preservation. Thus, the VAPP Project not only provided new insights into past human behavior for academic and public audiences, but also contributed to virtual curation of cultural heritage resources.
In addition to the external observations made on teeth that can be viewed with the naked eye or low magnification, we used advanced virtual imaging technologies to explore the morphology that is found beneath the surfaces of teeth. Virtual images were created using non-destructive, x-ray microcomputed tomography (microCT) to obtain high-resolution images of internal dental morphology that could be reconstructed for three-dimensional (3D) analysis of tissue proportions (i.e. the relative amount of enamel, dentin, and pulp), the shape of the enamel-dentin junction (where the enamel and dentin meet), and enamel thickness. These variables provide fine-grained insights into human population dynamics that may not be possible from external morphology (e.g. because tooth wear during life removes relevant cusp morphology) or aspects of selection—such as changes in tissue proportions or enamel thickness—that may correspond to changing diet and food processing technology throughout human evolution.
During the project a large and unique virtual database of archaeological human teeth was amassed that will greatly improve our understanding of human biocultural evolution in Portugal but also provide an important source of comparative material for exploring broader, interregional patterning of dental microevolution and how this reflects human behavior in the past. Not only will this provide more nuanced understanding of population dynamics in the past, but specific dental traits not previously explored from the standpoint of external and internal morphology (e.g. lateral incisor mesial bending) will be more fully understood.
Importantly, the project explored non-destructive means of assessing human population dynamics and behavior that ensures opportunities for future research focused on these finite cultural heritage resources while also providing a virtual record of their current state of preservation. Thus, the VAPP Project not only provided new insights into past human behavior for academic and public audiences, but also contributed to virtual curation of cultural heritage resources.
During the VAPP Project, virtual and external datasets were collected and analyzed to address our research objectives. External morphology was examined using the Arizona State University Dental Anthropology System (ASUDAS) to categorize discrete crown and root traits, digital photography of occlusal surfaces to assess contour shape and cusp morphology, and standard dental metrics. MicroCT was used to construct virtual models of archaeological human teeth from Late Middle Pleistocene (Gruta da Aroeira), Upper Paleolithic (Galeria da Cisterna and Gruta da Caldeirão), Neolithic, and historic archaeological sites from Portugal. An additional virtual methodology—close-range photogrammetry—was also employed during the project as a means of sharing 3D models with realistic photographic textures in academic and public domains.
Virtual methodologies are not only powerful tools for examining biological variation but also provide a useful means of data visualization and dissemination. While microCT reconstruction provides internal and external morphological information, it does not provide realistic photographic textured surfaces. Likewise, access to microCT facilities is not always available to researchers. As such, the use of photogrammetry was explored during the project when microCT access was interrupted. The appeal of photogrammetry for virtual anthropology is its use of basic laboratory equipment (camera, tripod, turntable) and open-source software. The photogrammetry portion of this project not only provided valuable additions to a publication but was also a useful visual tool for disseminating results in public forums (e.g. blog posts and social media).
In addition to standard ASUDAS traits, supplemental traits were scored, and one trait was examined in greater detail: lateral incisor mesial bending. MicroCT investigation of the enamel-dentin junction of this trait is currently underway and an open-access virtual reference plaque is being created that can also be 3D printed to facilitate the documentation of this trait more widely.
Analysis of intra-site enamel-dentin junction morphology of the Tholos of Paimogo I is also underway. Previous ancient DNA and dental morphology analyses concentrated on inter-site variation and small samples, whereas the virtual analyses of enamel-dentin junction morphology will allow analyses of a large sample (~ 35 individuals based on upper right first molars). This has great potential for understanding the degree of biological heterogeneity (or lack thereof) within one of the largest Late Neolithic/Chalcolithic mortuary complexes in Portugal.
In addition to ongoing analyses and published results (Willman et al., 2021), the fellow participated in several conferences, co-hosted a successful virtual public lecture series (Encounters with Our Past: Seminars in Prehistory and Related Disciplines) and dental morphology workshop, and provided numerous virtual lectures and outreach events for international audiences.
Reference:
Willman, J. C., Valera, A. C., & Silva, A. M. (2021). The embodiment of craft production in Bronze Age Portugal: Exceptional dental wear grooves in an individual from Monte do Vale do Ouro 2 (Ferreira do Alentejo, Portugal). International Journal of Osteoarchaeology, 31(2), 252-262. DOI: 10.1002/oa.2944
Virtual methodologies are not only powerful tools for examining biological variation but also provide a useful means of data visualization and dissemination. While microCT reconstruction provides internal and external morphological information, it does not provide realistic photographic textured surfaces. Likewise, access to microCT facilities is not always available to researchers. As such, the use of photogrammetry was explored during the project when microCT access was interrupted. The appeal of photogrammetry for virtual anthropology is its use of basic laboratory equipment (camera, tripod, turntable) and open-source software. The photogrammetry portion of this project not only provided valuable additions to a publication but was also a useful visual tool for disseminating results in public forums (e.g. blog posts and social media).
In addition to standard ASUDAS traits, supplemental traits were scored, and one trait was examined in greater detail: lateral incisor mesial bending. MicroCT investigation of the enamel-dentin junction of this trait is currently underway and an open-access virtual reference plaque is being created that can also be 3D printed to facilitate the documentation of this trait more widely.
Analysis of intra-site enamel-dentin junction morphology of the Tholos of Paimogo I is also underway. Previous ancient DNA and dental morphology analyses concentrated on inter-site variation and small samples, whereas the virtual analyses of enamel-dentin junction morphology will allow analyses of a large sample (~ 35 individuals based on upper right first molars). This has great potential for understanding the degree of biological heterogeneity (or lack thereof) within one of the largest Late Neolithic/Chalcolithic mortuary complexes in Portugal.
In addition to ongoing analyses and published results (Willman et al., 2021), the fellow participated in several conferences, co-hosted a successful virtual public lecture series (Encounters with Our Past: Seminars in Prehistory and Related Disciplines) and dental morphology workshop, and provided numerous virtual lectures and outreach events for international audiences.
Reference:
Willman, J. C., Valera, A. C., & Silva, A. M. (2021). The embodiment of craft production in Bronze Age Portugal: Exceptional dental wear grooves in an individual from Monte do Vale do Ouro 2 (Ferreira do Alentejo, Portugal). International Journal of Osteoarchaeology, 31(2), 252-262. DOI: 10.1002/oa.2944
Out initial findings reinforce the utility of a multi-methodological approach to dental morphological analyses. Considering the interruptions to mobility throughout the duration of the project, the use of external observations and photogrammetry meant that data collection and analyses could still be conducted until access to microCT infrastructure was possible. Furthermore, the use of dental morphology is not only non-destructive, but allows a relatively large sample size when compared to (destructive) ancient DNA analyses. Furthermore, virtual anthropological methods provide a high-resolution virtual dataset of archaeological human remains. These datasets provide a virtual record of these finite sources of data on past human lifeways.
The public’s inherent fascination with archaeology and past human lifeways ensured the success of our public outreach initiatives, and virtual approaches provided incredible visuals to summarize in accessible format for scientific communication with the public.
The public’s inherent fascination with archaeology and past human lifeways ensured the success of our public outreach initiatives, and virtual approaches provided incredible visuals to summarize in accessible format for scientific communication with the public.