Announcing the Final Examination of Ms. Cayli J. Meizel-Lambert for the degree of Master of Arts in Anthropology.
Thesis Title: Chemical Differentiation of Human Osseous, Non-human Osseous, and Non-osseous Materials Using Scanning Electron Microscopy – Energy Dispersive X-ray Spectrometry (SEM/EDX) and Multivariate Statistical Analysis
Identification of osseous materials is generally established on gross anatomical features; however, highly fragmented or taphonomically altered materials are often problematic. Recently, chemical analysis has been proposed to sort unknown materials according to their Ca/P ratios (Ubelaker et al., 2002; Christensen et al., 2012). An alternative method involves performing principal component analysis (PCA) on element spectra to classify unknown materials based on their trace element composition (Zimmerman, 2013).
The study sample contained 60 human osseous, non-human osseous, and non-osseous materials. Elemental weight percent data was collected with SEM/EDX and analyzed using PCA and Fisher Linear Discriminant Analysis. After outliers were removed correct classification of osseous and non-osseous materials was 98.02% with only one of 1504 osseous and 39 of 520 non-osseous spectra misclassifying. The single misclassifying bone spectra did not change the overall classification because 40 spectra were collected per sample. Therefore, a 100% correct classification of osseous materials was demonstrated. Differentiation of human and non-human osseous materials resulted in a poor classification (72.41%). Finally, a blind study using 20 unknown osseous and non-osseous samples assessed the applicability of this method and correctly classified all samples resulting in 100% correct classification.
Improving chemical analysis methodologies used for material differentiation, such as the one presented in this study, would provide forensic anthropologists an initial step for identifying fragmentary and taphonomically modified osseous and non-osseous materials for forensic investigations, reducing time and cost investments spent on non-forensically significant samples.
Outline of Studies:
Major: Anthropology
Educational Career:
B.S., 2012, Western Carolina University
Committee in Charge:
Dr. John J. Schultz
Dr. Michael E. Sigman
Dr. J. Marla Toyne
Approved for distribution by John J. Schultz, Committee Chair, on April 22, 2014.
The public is welcome to attend.
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