A Combined Morphometric Analysis of Foot Form and Its Association with Sex, Stature, and Body Mass Jacqueline Domjanic, 1 Horst Seidler, 2 and Philipp Mitteroecker 3 * 1 Department of Clothing Technology, University of Zagreb, Croatia 2 Department of Anthropology, University of Vienna, Austria 3 Department of Theoretical Biology, University of Vienna, Althanstrasse 14, Vienna, A-1090, Austria KEY WORDS BMI; footprint; foot shape; forensics; Procrustes; sexual dimorphism ABSTRACT Objectives: Morphometric analysis of footprints is a classic means for orthopedic diagnosis. In forensics and physical anthropology, it is commonly used for the estimation of stature and body mass. We studied individual variation and sexual dimorphism of foot dimensions and footprint shape by a combination of classic foot measurements and geometric morphomet- ric methods. Methods: Left and right feet of 134 healthy adult males and females were scanned twice with a 3D optical laser scanner, and stature as well as body mass were recorded. Foot length and width were measured on the 3D scans. The 2D footprints were extracted as the plantar-most 2 mm of the 3D scans and measured with 85 landmarks and semilandmarks. Results: Both foot size and footprint shape are sexually dimorphic and relate to stature and body mass. While dimorphism in foot length largely results from dimorphism in stat- ure, dimorphism in footprint shape partly owes to the dimorphism in BMI. Stature could be estimated well based on foot length (R 2 5 0.76), whereas body mass was more closely related to foot width (R 2 5 0.62). Sex could be estimated correctly for 95% of the individuals based on a combination of foot width and length. Dis- cussion: Geometric morphometrics proved to be an effective tool for the detailed analysis of footprint shape. However, for the estimation of stature, body mass, and sex, shape variables did not consider- ably improve estimates based on foot length and width. Am J Phys Anthropol 000:000–000, 2015. V C 2015 Wiley Periodicals, Inc. Size and shape of the human foot are highly variable and differ between age groups, populations, and sexes (Martin, 1914; Ashizawa et al., 1997; Wunderlich and Cavanagh, 2001; Kraus et al., 2008). Foot form is affected by life style, such as shoe wear and body mass (Krishan, 2008a; Mauch et al., 2008; Domjanic et al., 2013). Understanding variability in foot form and its underlying causes thus is crucial in orthopedics and orthotics as well as for shoe design. Morphometric descriptors of the two-dimensional foot- print form have been commonly used in orthopedic diag- nosis (Razeghi and Batt, 2002; Kennedy et al., 2003; Luximon and Goonetilleke, 2004; Xiong et al., 2008) and forensics (Barker and Scheuer, 1998; Krishan, 2007). For example, measures of foot length and width have been used to estimate stature and body mass in various foren- sic contexts (Krishan, 2008a,b; Agnihotri et al., 2007). In physical anthropology, comparative studies of footprint form have been used for the interpretation of fossilized footprints, such as those of Laetoli (3.6 million years ago), Ileret (1.5 mya), and Happisburgh (between 1 and 0.78 mya), the oldest preserved footprints in Africa and Europe, respectively (Day and Wickens, 1980; Tuttle et al., 1990; Bennet et al., 2009; Raichlen et al., 2010; Crompton et al., 2012; Ashton et al., 2014; Bennet and Morse, 2014). Most studies of footprint form in orthopedics, foren- sics, and anthropology are based on classic measure- ments of selected distances and angles (Razeghi and Batt, 2002; Xiong et al., 2008). In Domjanic et al. (2013), we introduced a geometric morphometric approach for the detailed assessment of the entire footprint outline. In this paper, we study foot dimensions and footprint shape in a sample of young adult central European males and females by combining and contrasting classic linear measurements and geometric morphometrics. We assess how size and shape of standing feet differ between males and females, and how much of these dif- ferences owe to the dimorphism in stature and body mass. Sex differences in the length and certain shape parameters of the foot are well documented, but the lit- erature is inconsistent regarding the dimorphism when accounting for differences in stature (Fessler et al., 2005). We further explore the influence of stature and body mass index (BMI) on footprint form and present models for the estimation of stature, body mass, and sex based on foot dimensions. Specifically, we investigate whether a geometric morphometric approach outper- forms classic measures for such estimations in forensic and anthropological contexts. MATERIALS AND METHODS A total of 134 healthy and randomly selected individu- als were invited to participate in the study. The sample comprises 83 females (aged between 19 and 36 years, mean age 23.4) and 51 males (aged between 19 and 38 *Correspondence to: Philipp Mitteroecker, Department of Theoret- ical Biology, University of Vienna, Althanstrasse 14, Vienna a-1090, Austria. E-mail: philipp.mitteroecker@univie.ac.at Received 16 September 2014; accepted 18 March 2015 DOI: 10.1002/ajpa.22752 Published online 00 Month 2015 in Wiley Online Library (wileyonlinelibrary.com). Ó 2015 WILEY PERIODICALS, INC. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 00:00–00 (2015)