Can ancestry be consistently determined from the skeleton?

Abstract

Although the concept of race has been thoroughly criticised in biological anthropology, forensic anthropology still uses a number of methods to determine the 'race' of a skeleton. The methods must be evaluated to see how effective they are given large individual variation. This study used 20 cases of skeletons of varied provenance to test whether the nine published methods of 'race' determination, using a range of various approaches, were able to consistently identify the ethnic origin. No one individual was identified as belonging to just one 'major racial class', e.g. European, meaning that complete consistency across all nine methods was not observed. In 14 cases (70%), various methods identified the same individual as belonging to all three racial classes. This suggests that the existing methods for the determination of 'race' are compromised. The very concept of 'race' is inapplicable to variation that occurs between populations only in small ways and the methods are limited by the geographic population from which their discriminant functions or observations of morphological traits were derived. Methods of multivariate linear discriminant analysis, e.g. CRANID, are supposed to allocate an individual skull to a specific population rather than a 'major race'. In our analysis CRANID did not produce convincing allocations of individual skeletons to specific populations. The findings of this study show that great caution must be taken when attempting to ascertain the 'race' of a skeleton, as the outcome is not only dependent on which skeletal sites are available for assessment, but also the degree to which the unknown skeleton's population of origin has been investigated.

Ancestry Estimation: Advances and Limitations in Forensic Applications

“…Some studies have shown low accuracy rates regarding the use of these software, although expectations based on the target sample should be considered when interpreting their conclusions. 8,[54][55][56][57] On the other hand, other studies demonstrated a 91% accuracy when using FORDISC in forensic casework. 58 At this point, worth mentioning is another, freely distributed, web-based software, (hu) MANid (https://anthropologyapps.shinyapps.io/humanid/), that contains a large reference sample of mandibular data (26 geographic or chronological populations) and utilizes both metric and morphoscopic traits providing sex and ancestry classifications.…”

“…5 Fundamental principles in which ancestry estimation is based are still questioned, more specifically in regards to population sampling and representation, validation studies, as well as applicability in day to day casework and ethical considerations. [6][7][8] In 1992, Sauer 9 summarized the controversy through a simple question: "If races don't exist, then why are forensic anthropologists so good at identifying them?". Ancestry is perhaps one of the most challenging aspects of biological profile as it constitutes a complex concept representing a bidirectional relationship between social constructs, environmental factors and biological characteristics.…”

The need to incorporate human variation and evolutionary theory in forensic anthropology: A call for reform

“…Likely, also due to the NAS report and rules surrounding admissibility of expert testimony, other research focused on how accurate estimates of ancestry are within a medicolegal context. Sierp and Henneberg (2015) evaluated 20 forensic anthropological cases for accuracy in ancestry estimates. They found that 14 (70%) provided ambiguous results, which they felt warranted "great caution in attempting to ascertain the 'race' of a skeleton" (Sierp & Henneberg, 2015, p. 21).…”

Virtual anthropology? Reliability of three-dimensional photogrammetry as a forensic anthropology measurement and documentation technique

“…On the other hand, Hefner (2003) defines ancestry as "ancestry is used to denote large groups of individuals who share similar morphologies in cranial form, likely the result of shared environmental constraints over great periods of time". It is the most controversial of all the elements of the biological profile (Schmitt et al, 2010;Blau & Briggs, 2011;Klales & Kenyhercz, 2014;Sierp & Henneberg, 2015), as some critics argue that biological races do not exist (Schmitt et al, 2010;Tersigni-Tarrant & Shirley, 2013). Additionally, not only are many of the craniofacial differences used in identification difficult to quantify (Sholts, Walker, Kuzminsky, Miller & Wärmländer, 2011), there is also considerable overlap of the traits that characterize different groups so that it is difficult to classify an individual into a particular ancestry (Schmitt et al, 2010).…”