RESUMO
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.
Assuntos
Cefalometria/métodos , Emigrantes e Imigrantes , Antropologia Forense/métodos , Migrantes , Adulto , Feminino , Humanos , Masculino , México , Crânio/anatomia & histologia , Estados UnidosRESUMO
The humanitarian crisis on the US-Mexico border is a long-standing and evolving crisis in which nearly 8,000 deaths have been reported in the last two decades. These deaths are largely distributed across the Arizona-Mexico and Texas-Mexico border regions, where demographic trends for immigrants attempting to cross into the United States have shifted dramatically. The demographic change and volume of immigrants seeking shelter in the United States present new challenges for the forensic practitioners entrusted with the identification of individuals who lose their lives during the final segment of their journey. Within this border context, this study investigated how genetic variation inferred from forensically significant microsatellites can provide valuable information on regions of origin for unidentified remains at the group level. To explore how to mobilize these genetic data to inform identification strategies, the authors conducted a comparative genetic analysis of identified and unidentified immigrant cases from the Arizona- and Texas-Mexico contexts, as well as 27 other Latin American groups. Allele frequencies were utilized to calculate FST, and relationships were visually depicted in a multidimensional scaling plot. A Spearman correlation coefficient analysis assessed the strength and significance of population relationships, and an agglomerative clustering analysis assessed population clusters. Results indicate that Arizona-Mexico immigrants have the strongest relationship (>80%) with groups from El Salvador, Guatemala, Mexico, and an indigenous group from southern Mexico. Texas-Mexico immigrants have the strongest relationships (>80%) with groups from Belize, Colombia, Costa Rica, El Salvador, Guatemala, Honduras, and Nicaragua. These findings agree with, and are discussed in comparison with, previously reported demographic trends, population genetics research, and population history analyses. The authors emphasize the utility and necessity of coupling genetic variation research with a nuanced anthropological perspective for identification processes in the US-Mexico border context.
Assuntos
Emigrantes e Imigrantes , Genética Populacional , Hispânico ou Latino , Arizona , Variação Genética , Hispânico ou Latino/genética , Humanos , América Latina , México , Texas , Estados UnidosRESUMO
This study examines levels of fluctuating asymmetry (FA) in Mexican residents, U.S. residents, and undocumented border crossers (UBCs) from Mexico to the United States. Craniofacial structures develop symmetrically under ideal circumstances; however, during periods of developmental stress random deviations from perfect symmetry, or FA, can occur. It is hypothesized that the UBC sample would represent individuals of a lower socioeconomic status (SES) who experienced higher stress levels during development, and that these individuals would consequently have higher levels of FA. Three-dimensional cranial landmarks were collected from 509 individuals representing the three resident groups. Geometric morphometric methods were used to calculate an FA score for each individual. The FA score provides a distance measure that is a scalar measure of the magnitude of FA in each individual. The results show that the difference in the means of the FA scores between UBCs and U.S. residents is 0.43 (pâ¯=â¯0.02), with UBCs showing significantly higher levels of FA compared to U.S. residents. Moreover, Mexican residents' FA levels are intermediate between and not significantly different from the other two samples. These results suggest that levels of FA may prove useful for reconstructing individuals' social and economic circumstances, and that craniofacial asymmetry provides a suitable biological marker for analyzing differences in SES among different groups.
Assuntos
Emigrantes e Imigrantes/estatística & dados numéricos , Assimetria Facial/etnologia , Americanos Mexicanos/estatística & dados numéricos , Crânio/anatomia & histologia , Adulto , Idoso , Biomarcadores , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Socioeconômicos , Imigrantes Indocumentados/estatística & dados numéricos , Estados Unidos/epidemiologiaRESUMO
Geographic Information Science (GIScience) technology has been used to document, investigate, and predict patterns that may be of utility in both forensic academic research and applied practice. In examining spatial and temporal trends of the mass disaster that is occurring along the U.S.-Mexico border, other researchers have highlighted predictive patterns for search and recovery efforts as well as water station placement. The purpose of this paper is to use previously collected spatial data of migrant deaths from Arizona to address issues of data uncertainty and data accuracy that affect our understanding of this phenomenon, including local and federal policies that impact the U.S.-Mexico border. The main objective of our study was to explore how the locations of migrant deaths have varied over time. Our results confirm patterns such as a lack of relationship between Border Patrol apprehensions and migrant deaths, as well as highlight new patterns such as the increased positional accuracy of migrant deaths recorded closer to the border. This paper highlights the importance of using positionally accurate data to detect spatio-temporal trends in forensic investigations of mass disasters: without qualitative and quantitative information concerning the accuracy of the data collected, the reliability of the results obtained remains questionable. We conclude by providing a set of guidelines for standardizing the collection and documentation of migrant remains at the U.S.-Mexico border.
Assuntos
Mortalidade , Análise Espacial , Migrantes/estatística & dados numéricos , Arizona , Desastres , Humanos , México/etnologiaRESUMO
Population-specific reference data are necessary for sex estimation in forensic anthropological practice. Currently, there are no population-specific data for Hispanics equivalent to data available for American Blacks and Whites. Individuals of Mexican origin represent the largest group of Hispanics in the United States (Spradley and Jantz. 2011. J Forensic Sci;56:289). This paper presents new population-specific sex estimation criteria for postcranial measurements for Mexican Hispanics. Metric data come from positively identified border-crossing fatalities at the Pima County Office of the Medical Examiner and documented cemetery collections curated at Universidad Nacional Autónoma de México and Universidad Autónoma de Yucatán. Stepwise variable selection procedures and discriminant function analyses were utilized to generate classification functions for postcrania. Sectioning points were also created for select measurements. Both the cross-validated classification rates and sectioning points achieved accuracy rates as high as 95% and 92%, respectively. These new criteria will improve sex estimation for US Mexico border crossers and Hispanics in the US.
Assuntos
Osso e Ossos/anatomia & histologia , Americanos Mexicanos , Determinação do Sexo pelo Esqueleto/métodos , Arizona , Análise Discriminante , Feminino , Antropologia Forense , Humanos , Masculino , México , Análise MultivariadaRESUMO
When forensic anthropologists estimate the sex of Hispanic skeletal remains using nonpopulation specific metric methods, initial observations cause males to frequently misclassify as female. To help improve these methods, this research uses postcranial measurements from United States-Mexico border migrant fatalities at the Pima County Office of the Medical Examiner in Tucson, Arizona, as well as Hispanic individuals from the Forensic Anthropology Data Bank. Using a total of 114 males and 28 females, sectioning points and discriminant functions provide classification rates as high as 89.43% for Hispanic individuals. A test sample assessed the reliability of these techniques resulting in accuracy up to 99.65%. The clavicle maximum length measurement provides the best univariate estimate of sex, while the radius provides the best multivariate estimated of sex. The results of this research highlight the need for population specific data in the creation of a biological profile, especially when working with individuals considered Hispanic.