Landmark and Measurement-Based Data Assistant (LAMbDA) A Pedagogical Tool for Cranial Landmark Data Collection

Abstract

Cranial landmarks have been used in research and casework since the late 19th century, at which time some of the earliest landmark and measurement definitions were codified. Over the last two to three decades, however, many biological anthropologists have shifted from taking traditional caliper-derived measurements to using a three-dimensional (3D) digitizer to collect spatial coordinate landmark data. The increasing use of landmark-based data collection methods have necessitated a shift in the practitioner’s focus from understanding measurement definitions to being able to identify the location of a particular landmark in three-dimensional space. As a result, the Harris County Institute of Forensic Sciences published a Standard Operating Procedure (SOP), which provides a comprehensive list of landmark definitions for practitioners to reference while digitizing. The movement toward open access resources and digital pedagogy led to the development of a digital companion to the current SOP, entitled Landmark and Measurement-based Data Assistant (LAMbDA). LAMbDA is a free, publicly-available web interface (www.locatelambda.org) that serves as a pedagogical resource and a repository of information for those using a digitizer to collect 3D cranial coordinate data. This tool provides a series of photogrammetry models with annotated landmarks so that proper landmark placement can be viewed in 3D space following definitions provided in the Harris County SOP. Additionally, the website provides useful references, a manual with landmark placement definitions and comments on special anatomical circumstances, supplementary photographs, and the 3D models are available to download for 3D printing physical models.