Application of the lateral angle method for sex determination of cremated individuals from burials of the Lusatian culture cemetery in Czernikowice, Poland

Abstract

Research of cremated human remains are limited by severe analytical constraints. Estimation of basic anthropological parameters such as sex of individuals or their age at death is often uncertain. A method for assessing the sex of cremated individuals measures the lateral angle of the petrous part (PP) of the temporal bone, known as the lateral angle (LA) method.
 In the cemetery of the Lusatian culture in Czernikowice (51.317389°N, 15.871469°E), 6 well-preserved PP were identified. The analyzed PP belonged to 6 different individuals: 3 adults and 3 children. Based on standard anthropological methods, sex was estimated for adults individuals: 2 males and 1 female. The identified PP served as the basis for application of the LA method. The bones were scanned by computed tomography (CT) and the tomographic imaging allowed measurement of the lateral angle.
 The absolute values of intra-observer errors did not exceed 1°. Relative technical errors of measurements (rTEM) fell in the range below 5%, which is indicative of their high precision. Individuals for which the LA value was greater than or equal to 45.0° were qualified as females and those for which it was less than 45.0° – as males. The LA values for female individuals ranged from 48.0 to 49.1°, (average 48.5±0.78°, median 48.4°) and for male individuals were in the range of 24.9-37.5° (average 33.4±5.80°, median 35.5°). The absolute difference between the average values for female and male individuals was considerable (15.1°) and statistically significant (p < 0.001).
 The LA method provides good reliability of measurements when it comes to this analysis with regard to cremated osteological material, and the use of non-invasive CT enhances its value in the context of archaeological remains. However, its capability for sexing subadult individuals should be approached with caution and requires further research.

Lateral angle: A landmark‐based method for the sex estimation in human cremated remains and application to an Austrian prehistoric sample

“…Interestingly, the mean lateral angle was on average smaller than all previously published studies (e.g., Gonçalves et al, 2015; Masotti et al, 2013) but closest to studies which focused on prehistoric cremated petrous bones (Hałuszko & Guziński, 2022). Interpopulation differences may increase the observed variability, however, one may expect similar variability in the lateral angle due to less phenotypic variability in modern humans (Pezo‐Lanfranco & Haetinger, 2021), at least in studies focusing on modern populations (e.g., forensic studies).…”

“…An absolute TEM of ±1.61° and a relative TEM of 5.17% was estimated. In previous studies the total inter‐ and intraobserver errors were estimated for the lateral angle based on CT scans (e.g., Hałuszko & Guziński, 2022; Morgan et al, 2013). However, the measurements of the lateral angle contain two steps in the workflow with unknown effects on precision and repeatability (plane setup and angle measurements).…”

“…Consequently, many of the guidelines for the measurement of the lateral angle based on CT scans are ill‐suited for micro‐CT data of isolated petrous bones. Multiplanar reconstructions (MPR) were preferable as already suggested by Hałuszko and Guziński (2022) and we decided to virtually follow the original protocols by Wahl (1981b) for the measurement based on the casts. As the petrous bones were deposited into centrifuge tubes for the CT scanning and as a consequence, the samples were located oblique in different angles to the scanning axes.…”

“…Due to its robustness, density and position in the cranial base, the pars petrosa frequently survives the cremation process in good condition and can also be easily identified because of its distinct shape (Kontopoulos et al, 2019; Lynnerup et al, 2006; Masotti et al, 2013; Masotti et al, 2019; Norén et al, 2005; Wahl, 1981b, 1982; Wahl & Graw, 2001; Wahl & Henke, 1980). Various anatomical structures have been found to be sexual dimorphic in unburnt (Akansel et al, 2008; Graw et al, 2005; Lynnerup et al, 2006; Norén et al, 2005; Wahl & Graw, 2001) and in burnt petrous portions (Boucherie et al, 2022; Masotti et al, 2019; Schutkowski & Herrmann, 1983; Wahl, 1981b), for example, the so‐called lateral angle (Graw et al, 2005; Hałuszko & Guziński, 2022; Kozerska et al, 2020; Norén et al, 2005; Wahl, 1981b), or the diameter of the internal acoustic meatus (Lynnerup et al, 2006; Pezo‐Lanfranco & Haetinger, 2021).…”

Let’s make a mess, maybe no one will notice. The impact of bioturbation activity on the urn fill condition

“…The sex of the individuals was estimated according to the methods based on morphological dimorphism of the skull and postcranial skeleton [38,61]. The lateral angle method was also used as a complementary method [62][63][64][65][66]. The age at death of non-adult individuals was determined on the dentition [67,68] and the skeleton stage of development [68][69][70], while the age of adult individuals was determined on the degree of obliteration of the cranial sutures [61,71,72] and tooth cementum annulation [73][74][75].…”