Use of craniometric data to facilitate migrant identifications at the United States/Mexico border

Abstract

Objectives: Thousands of migrants have died along the United States/Mexico border and many remain unidentified. The purpose of this research is to test whether estimations of population affinity, derived from craniometric data, can facilitate identification of migrant remains and provide a geographic region of origin rather than the broad label Hispanic. The appropriateness of current forensic reference data will also be assessed. Methods: A case study combined with craniometric data from positively identified and unidentified migrants from the Pima County Office of the Medical Examiner (n = 489) in Arizona and operation identification (n = 201) in Texas were compared to skeletal data representing Guatemalan (n = 87) and Mexican (n = 65) Mayans. Biological distance and discriminant function analyses were used to assess overall population relationships and classificatory models for forensic anthropological application.Results: The majority of evidence indicates that estimations of population affinity can assist in the facilitation identification of migrant remains, even when a broad classification is used. Biological distances among the groups suggest that positively identified Guatemalan and Mexican migrants are similar to one another but differ from Guatemalan and Mexican Mayans.Conclusions: Population affinity estimations can aid migrant identification, and current reference data used in forensic anthropological practice should be replaced with data from positive identifications. Estimates of geographic origin may be more useful than the broad generic term Hispanic for narrowing down the search for a missing person, but more data and research is needed to achieve this goal. Although, the utility of geographic origin estimates relies on transnational data centralization and sharing, which is not always the case.

How Physical and Molecular Anthropology Interplay in the Creation of Biological Profiles of Unidentified Migrants

“…The size of the sample was limited to 21 crania that were already genotyped for identification purposes; inter-individual variability of such fluctuating features for sex and ancestry estimation within this pool of crania may be therefore clarified by increasing the sample. When applying statistical methods for ancestry and sex estimation, anthropologists must consider that the reference population data may not be appropriate and representative of the sample of the study [ 5 ]. Another factor influencing the analyses may be related to secular change [ 6 , 13 ] potentially experienced by this population, which would benefit from further investigation.…”

“…Within this plight, the victims’ rights to identity and the relatives’ rights to know should always be granted [ 4 ]. Therefore, forensic investigators have been requested to give a name to a victim, and, as part of their procedure, to first determine their biological profile that will provide insightful information to be compared against missing persons’ data [ 5 ]. To do so, forensic experts must begin, particularly when working on skeletal remains, with estimations of biological sex, ancestry, age at death, and stature.…”

“…Craniometric analysis represents a reliable mean for biological sex and ancestry estimation, although the lack of reference samples from which the statistical framework is inferred could complicate interpretation of the results [ 13 ]. However, in investigations such as the identification of unknown migrants, craniometric data have proven to be valuable indicators for classification into ancestral groups [ 5 ].…”

What Are We Really Estimating in Forensic Anthropological Practice, Population Affinity or Ancestry?

“…Our results indicate similarity Hispanic Americans and Mexican migrants; however, they are also differentiated. The Mexican migrants are less similar to the Mexican and Guatemalan Mayans as they are thought to exhibit more admixture (Spradley 2021), yet they are still differentiated from Hispanic Americans with Mexican ancestry.…”

“…Latin American data are represented by indigenous Guatemalan and Mexican Mayans and migrants from Mexico and Guatemala that died in U.S./Mexico border states, predominately Arizona and Texas and (Spradley 2020). All Latin American groups, Mexican and Guatemalan Mayan and migrants, have 20th century birth years and are well defined in the literature (Hughes et al 2017;Spradley 2021). A Southwest Native American group, Zuni, was also included in the analysis in addition to two Asian groups, Hainan (Howells 1989) and Japanese (Dudzik 2015).…”