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Advances In Forensic Anthropology: 3D-ID

You can learn a lot from a skull.

Note: This is the first of three posts outlining recent technological advances in forensic science, which were the focus of a workshop held earlier this month at NC State. The workshop, Advances In Forensic Anthropology, was funded by the National Institute of Justice (NIJ) and organized by the National Forensic Science Technology Center.

Sometimes law enforcement officials find partial human remains: like a human skull, with few or no other skeletal remains. How can you tell if it was even a man or woman? New technology called 3D-ID can help – giving forensic scientists information about a person’s sex and ancestral background based solely on the measurements of the skull.

3D-ID is a software program that relies on shape analysis using “geometric morphometrics” – a field of study that characterizes and assesses biological forms.

Forensic practitioners, such as medical examiners, are required to take measurements of 34 specific points on the skull using a “digitizer,” which is basically an electronic pen that records the coordinates of each point (a grad student is using a digitizer in the photo above). The 3D-ID software then performs an analysis that uses these measurements to determine the ancestry and sex of the skull.

3D-ID does this by comparing the skull’s dimensions to a data library of 1300 individuals representing a wide variety of populations. The program can provide a significant level of detail using only a skull. For example, a skull may be identified as being Hispanic of South American origin, Hispanic of Mesoamerican origin or Hispanic of Caribbean origin – not just “Hispanic.”

The program can also be used when all 34 reference points of the skull can’t be measured, as with skulls that have deteriorated or suffered traumatic injury. The use of fewer datapoints does not necessarily affect the accuracy of 3D-ID’s findings, but it may – depending on how or whether the skull’s measurements match up with the reference database of skulls.

The 3D-ID program was developed by forensic anthropologist Ann Ross of NC State and scientific computing researcher Dennis Slice of Florida State University. Ross and Slice did the work under a grant from NIJ and issued 3D-ID in 2010.

In fact, all of the technologies presented at the Advances In Forensic Anthropology workshop were funded by NIJ. The overall goal of the workshop was to bring practicing forensic scientists up to speed on recent technologies, so they can be used in the field to assist in body identification, murder and missing persons investigations, and other legal and medical cases.

Future posts in this series will cover a national database of unidentified bodies and missing persons, and an emerging technology that uses computerized tomography (CT) scans of the skull to recreate what that person looked like when alive.