National Institute of Justice and North Carolina State University
When forensic anthropologists investigate unidentified remains, they look for important clues that can help identify the subject. For example, the size and shape of the skull can be used to predict a subject’s ancestry and sex, details that can play a key role in narrowing down the identity of the decedent. Traditionally, the methods used to characterize the shape and size of a skull involve multivariate statistical analysis techniques that measure disparate linear distances between anatomical landmarks on the skull. However, this approach provides limited information on the shape of the skull, as these linear distances are measured in two dimensions and not in relation to other measurements. Geometric morphometric (GM) analysis records the same anatomical landmarks, but in relation to each other in three dimensions (X, Y, Z coordinates), providing a more biologically informative perspective of the skull that can better characterize the form (i.e., both shape and size) of the skull. GM uses archive or reference data to compare standard coordinate data and, thereby, estimate sex and ancestry for unknown individuals. The use of GM is challenging, however, as the coordinate data associated with the anatomical landmarks must be standardized for direct comparison, which requires additional analysis. While valuable, this technique has not been used commonly in forensic anthropology. To drive the application of GM analysis in forensic anthropology, Dr. Ann Ross and Dr. Dennis Slice developed 3D-ID, a no-cost software that enables the forensic anthropologist to estimate sex and ancestry for unknown crania using GM methods.
“3D-ID has been an invaluable tool for us. Many of our unknown persons come from populations south of the Border. We use this program for every case with great success. It has also been a great tool to combine with chemical isotope data, providing a very accurate and powerful result, even in the most complex cases.”
- Erin Kimmerle, Ph.D. | Director, Florida Institute of Forensic Anthropology and Applied Science, University of Florida
Funding for this Forensic Technology Center of Excellence success story was provided by the National Institute of Justice, Office of Justice Programs, U.S. Department of Justice.
The opinions, findings, and conclusions or recommendations expressed in this success story are those of the author(s) and do not necessarily reflect those of the U.S. Department of Justice.