ABSTRACT
As a consequence of the recent history of Argentina related to crimes against humanity, the country has positioned itself as a leader on Forensic Anthropology in human rights contexts. To some extent it can even be argued that Forensic Genetics for human identification had its origins in human rights work in the early 1980s in Argentina. However, there are still hundreds of unidentified human remains recovered from the dictatorial regimes' crimes. Additionally, every year there are dozens of unidentified deceased buried in public cemeteries. Thus, there is an urgent need to adopt new techniques that could increase the biological profile of a person, and therefore increase the chances of positive identifications. One of such initiatives is the development of isotopic databases and models that can provide information on the population and region of origin of unidentified victims. We present the development of an isotopic database of modern human tissues named BITACORA (from its name in Spanish: Base de Información Isotópica de Tejidos Actuales Como Referencia Argentina). BITACORA holds isotopic data (δ18O, δ2H, δ13C, δ15N and δ34S values) from teeth (enamel and dentine) and keratin tissues (scalp hair, beard and fingernails) obtained from volunteers of known origin, as well as individual information of the donors (age, gender, biometrics, dietary preferences, and relocation history). BITACORA is associated with a tap water isotope database. Currently, we have 345 keratin, 273 teeth and 287 tap water samples gathered from across the country. We present preliminary analyses on the geographic distribution of these isotopic markers, and provide an overall discussion of the current status and future development of the databases.
Subject(s)
Forensic Anthropology , Keratins , Humans , Oxygen Isotopes/analysis , Argentina , Water/analysisABSTRACT
Out of all the available methods for estimating age at death from immature human skeletal remains, those based on odontometric variables of deciduous dentition have proved to be one of the most accurate. The development of odontometric methods has been improved through the creation of documented human osteological collections, allowing their validation in different populations. The present study aims to test the regression equations for age estimation proposed by Liversidge et al. 1993, Irurita Olivares et al. 2014, and Cardoso et al. 2019, on the basis of the maximum length of deciduous teeth in an Argentinian sample of 35 infants of known age at death. The results showed that the absolute mean difference between estimated and chronological age was 5.76±6.33 weeks for Liversidge's method, 5.71±6.41 weeks for Irurita Olivares's method, and 6.79±5.80 for Cardoso's method. It was also found that, for Liversidge's method, the canines provided the most accurate and the least biased estimations. For Irurita Olivares's method, mandibular anterior teeth were the most accurate, while the first mandibular molars offered the least biased estimations. For Cardoso's method, the canines presented the most accurate estimations, while the lateral incisors the least biased ones. Finally, 95% confidence intervals of estimated ages were calculated for each method, finding that Irurita Olivares's method provided the most reliable age estimations when using mandibular central incisors and mandibular first molars.
Subject(s)
Age Determination by Teeth/methods , Tooth, Deciduous , Argentina , Child, Preschool , Cuspid/anatomy & histology , Female , Forensic Dentistry , Humans , Incisor/anatomy & histology , Infant , Infant, Newborn , Male , Mandible , Molar/anatomy & histology , Regression AnalysisABSTRACT
The study of carrion fauna associated with buried human corpses from a forensic perspective could provide useful information in criminal investigations. Insects and other arthropods remains sampled of 44 legally exhumed infant skeletons from La Plata (Buenos Aires, Argentina). They were identified at different taxonomic levels depending on the state of preservation. The specific diversity, abundance and frequency were analyzed and each taxon was assigned to the hypothetical colonization sequence: burial colonization, post-exhumation contamination at cemetery deposit or soil fauna. The phorid Dohrniphora sp. is mentioned for the first time in Argentina as carrion fauna of underground colonization, and the assemblage of Dohrniphora sp., Megaselia scalaris and Hydrotaea aenescens is proposed as indicator of buried cadavers. These findings provide new useful data to be applied in forensic entomology research.
Subject(s)
Burial , Feeding Behavior , Invertebrates , Postmortem Changes , Animals , Argentina , Entomology , Exhumation , Forensic Anthropology , Forensic Pathology , Humans , Infant , Infant, NewbornABSTRACT
Introducción. Este trabajo tiene por objeto evaluar la aplicabilidad y precisión de 4 métodos para estimar la edad por el desarrollo de la dentición en el período posnatal temprano. Material y métodos. Para la realización de este estudio se seleccionó una muestra constituida por 25 individuos de ambos sexos, sin evidencias de enfermedades y con edades documentadas entre 0 y 6 meses posnatales. Se estimaron las edades dentales mediante la utilización de los trabajos de Moorrees et al. (1963a; b), Lunt y Law (1974), Ubelaker (1978) y AlQahtani et al. (2010) y se compararon las edades estimadas con la edad cronológica documentada para cada individuo de la muestra. Resultados. Los resultados mostraron que el método de Moorrees no es adecuado para el período de edad analizado dado no permitió estimar la edad del total de los individuos de la muestra y las edades estimadas presentan diferencias significativas con las edades cronológicas documentadas. Los métodos de Lunt y Law y Ubelaker son poco precisos y el método de AlQahtani es el que arrojó mayor exactitud respecto de la edad cronológica documentada. Conclusiones. A partir de los resultados se llegó a la conclusión de que los métodos gráficos son de muy fácil aplicación sin detrimento de la precisión que pueden conseguir en la estimación, y que el método de AlQahtani es el que presenta mayor precisión y exactitud en el rango etario analizado (AU)
Introduction. This work aims to assess the applicability, accuracy and precision of four methods for estimating age by tooth development in the early postnatal period. Material and methods. To perform this study a sample of 25 individuals of both sexes, with no evidence of pathology and documented ages from 0 to 6 postnatal months was selected. Dental ages were estimated using reference data from Moorrees et al. (1963), Lunt and Law (1974), Ubelaker (1978) and AlQahtani et al. (2010). Estimated and chronological documented ages were compared. Results. The results showed that the Moorrees et al. method is not suitable for the targeted age group as it was not possible to estimate the age of all individuals in the sample and the estimated ages had significant differences with documented chronological age. Lunt and Law and Ubelaker methods are vague and AlQahtani et al. method is more accurate. Conclusions. On the basis of the results it is concluded that graphical methods are easily applied without loss of accuracy and that the most accurate and precise method is by AlQahtani et al (AU)
