Original communication Sex determination in a contemporary Mexican population using the scapula * Allison Hudson a , Tanya R. Peckmann b, * , Ciara J. Logar c , Susan Meek d a Faculty of Medicine, Dalhousie University, Halifax, Nova Scotia, B3H 4R2, Canada b Forensic Sciences Program, Department of Anthropology, Saint Mary's University, Halifax, Nova Scotia, B3H 3C3, Canada c Department of Anthropology, Saint Mary's University, Halifax, Nova Scotia, B3H 3C3, Canada d Department of Biology, Saint Mary's University, Halifax, Nova Scotia, B3H 3C3, Canada article info Article history: Received 1 June 2015 Accepted 10 November 2015 Available online xxx Keywords: Forensic anthropology population data Adults Scapula Sex determination Discriminant functions Mexico abstract The scapula is useful for sex determination in human skeletons. Muscles provide protection to the scapula making it difficult to fracture, therefore increasing the potential for undamaged scapulae at forensic scenes. The goal of this project is to evaluate the accuracy of discriminant functions, created using an indigenous Guatemalan population when applied to a contemporary Mexican sample for determination of sex from the scapula. The length of the glenoid cavity (LGC) and breadth of the glenoid cavity (BGC) were measured. The sample included 177 individuals (101 males and 76 females) with age ranges from 21 to 100 years old. When the Guatemalan discriminant functions were applied to the Mexican sample they showed high accuracy rates for sexing male scapulae (100%) and low accuracy rates for sexing female scapulae (48.68%e51.32%). Size comparisons were made to an indigenous Guatemalan sample and a contemporary White sample. Overall, LGC and BGC were larger in the Mexican sample than in the Guatemalan sample but LGC and BGC were smaller in the Mexican sample than in the White sample. Population-specific discriminant functions were created for the Mexican population with an overall sex classification accuracy rate of 83.6%e89.3%. © 2015 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved. 1. Introduction South and Central America are scattered with the bones of civil conflict. In the past 30 years, the United Nations has handled more than 51,000 cases of enforced disappearance with thousands of more individuals who remain unidentified in mass graves. 1 Accu- rate sex determination techniques for human skeletal remains are necessary to aid in the identification of these missing individuals. However, many of the techniques utilized by forensic anthropolo- gists were developed using non-Latin American populations. Discriminant function equations for sex determination have been shown to be population specific. 2,3 Even within small geographic areas researchers have found variation in sexual dimorphism requiring the development of population-specific discriminant function equations. 4e6 Currently, the only scapular discriminant function equations available for the determination of sex for a Latin American population are those developed from an indigenous Guatemalan population. 7 The accuracy of these func- tions ranged from 89.2% to 94.6% for correct sex identification. 7 In 1894, Dwight demonstrated that maximum scapular length and glenoid cavity were useful indicators of sex. 8 The infraspinous and supraspinous fossa of the scapula are more commonly eroded due to taphonomic processes but the spine and the glenoid cavity are often available for forensic analyses. 9,10 Scapular muscle at- tachments provide protection to the bone making it difficult to fracture or break. 11 The goals of this project are to (1) apply the indigenous Guatemalan scapular discriminant functions to a contemporary Mexican population and, (2) develop population specific discriminant function equations for sexing skeletons from a contemporary Mexican population. 2. Materials and methods This research utilized 177 individuals (101 males and 76 females) from the Laboratorio de Antropologia Fisica Departamento de Anatomia, which is housed within the Faculty of Medicine at the * This research has not been presented at any meetings or conferences. * Corresponding author. Saint Mary's University, Forensic Sciences Program, 923 Robie Street, Halifax, Nova Scotia, B3H 3C3, Canada. Tel.: þ1 902 496 8719. E-mail addresses: allison.hudson@dal.ca (A. Hudson), tanya.peckmann@smu.ca (T.R. Peckmann), ciara.logar@smu.ca (C.J. Logar), susan.meek@smu.ca (S. Meek). Contents lists available at ScienceDirect Journal of Forensic and Legal Medicine journal homepage: www.elsevier.com/locate/jflm http://dx.doi.org/10.1016/j.jflm.2015.11.006 1752-928X/© 2015 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved. Journal of Forensic and Legal Medicine 37 (2016) 91e96