Evaluación del sesgo en las clasificaciones taxonómicas del índice cefálico

El índice cefálico (ic) ha sido ampliamente utilizado para establecer categorías taxonómicas humanas. Aunque su significado biológico ha sido discutido, pocos trabajos han analizado la relación numérica del índice y sus clasificaciones. Aquí se aborda uno de los sesgos introducidos por la transformación en categorías de clase (braquicefalia, mesocefalia y dolicocefalia) de la distribución continua del ic, se analiza el efecto que tiene en la varianza poblacional y en la densidad de los datos. Por medio de la Howells World Data Set recurrimos al coeficiente de determinación como estimador de la cantidad de información que se conserva posterior a la trans- formación categórica del ic. Nuestros resultados indican que las clasificaciones del ic son un reducto de la variabilidad biológica craneal de las poblaciones humanas. La adopción de modelos no lineales hiperdimensionales y multivariados representa un mejor acercamiento a la covariación de las formas biológicas.The cephalic index (ic) has been widely used as one of the higher profile tools to establish human taxonomy categories. Although it has been discussed the biological sense of the cephalic index, few studies analyzed the mathematics relations of the ratio and their classifications. In this paper, we address one of the biases introduced by the transformation into class categories (brachycephaly, mesocephaly and dolichocephaly) of the continuous distribution of IC, analyzing the effect in the population variance and the density of the data. Thus, we used Howells World Data Set for determination coefficient as an estimate of amount of information retained after processing IC categories. Our results indicate that the ratings of the IC are a haven of cranial biological variability of human populations. The adoption of hyperdimensional non-linear and multivariate models represents a better approach to the covariance of biological forms.Fil: Gomez Valdes, Jorge A.. Universidad Nacional Autónoma de México; MéxicoFil: Quinto Sanchez, Mirsha Emmanuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentin

Predicting Physical Features and Diseases by DNA Analysis: Current Advances and Future Challenges

The 'omics' era and its concomitant technological advances have brought great insight into genetics. One of the most promising fields within human genetics is the prediction of physical traits from analysis of genetic material. Besides the predictive potential of DNA, the traceability of pathogenic agents in the human body through molecular analysis is also a field to be further exploited. In this review, we aim to discuss specific aspects of phenotypic prediction by analysing DNA, with special emphasis on normal variation, and the application of a technology known as ‘Forensic DNA Phenotyping’ (FDP). We also suggest the term ‘Phenotype Informative Markers’ (PIMs) to designate any molecular markers responsible for normal or pathological human phenotypic variation. In addition, we raise some recommendations related to forensic genetics, the molecular diagnosis of human diseases, and the traceability of pathogens in the human body, giving special emphasis to the need for validation of these tests with strict protocols. Some relevant concerns about privacy, ethics, and legality of such predictions have also been discussed. Finally, we look at perspectives on the use of epigenetic tools, and quote some examples of what has been done in this specific field.Fil: Silva de Cerqueira, Caio Cesar. Scientific Police Of Sao Paulo State; BrasilFil: Ramallo, Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Ciencias Sociales y Humanas; ArgentinaFil: Hünemeier, Tábita. Universidade de Sao Paulo; BrasilFil: de Azevedo, Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Ciencias Sociales y Humanas; ArgentinaFil: Quinto Sanchez, Mirsha Emmanuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Ciencias Sociales y Humanas; ArgentinaFil: Paschetta, Carolina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Ciencias Sociales y Humanas; ArgentinaFil: Cintas, Celia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Ciencias Sociales y Humanas; ArgentinaFil: González, Marina Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Ciencias Sociales y Humanas; ArgentinaFil: Schüler-faccini, Lavinia. Universidade Federal do Rio Grande do Sul; Brasil. National Institute of Medical Genetics Population; BrasilFil: Bortolini, María Cátira. Universidade Federal do Rio Grande do Sul; BrasilFil: González José, Rolando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Ciencias Sociales y Humanas; Argentin

The effects of forest degradation on arboreal primates within Sikundur, the Gunung Leuser Ecosystem, Northern Sumatra

Abstract of a paper given at the 87th Annual Meeting of the American Association of Physical Anthropologists held at Austin, Texas, 11-14 April 201

Latin Americans show wide-spread Converso ancestry and imprint of local Native ancestry on physical appearance

Historical records and genetic analyses indicate that Latin Americans trace their ancestry mainly to the intermixing (admixture) of Native Americans, Europeans and Sub-Saharan Africans. Using novel haplotype-based methods, here we infer sub-continental ancestry in over 6,500 Latin Americans and evaluate the impact of regional ancestry variation on physical appearance. We find that Native American ancestry components in Latin Americans correspond geographically to the present-day genetic structure of Native groups, and that sources of non-Native ancestry, and admixture timings, match documented migratory flows. We also detect South/East Mediterranean ancestry across Latin America, probably stemming mostly from the clandestine colonial migration of Christian converts of non-European origin (Conversos). Furthermore, we find that ancestry related to highland (Central Andean) versus lowland (Mapuche) Natives is associated with variation in facial features, particularly nose morphology, and detect significant differences in allele frequencies between these groups at loci previously associated with nose morphology in this sample.Instituto Multidisciplinario de Biología Celula

Latin Americans show wide-spread Converso ancestry and imprint of local Native ancestry on physical appearance

Historical records and genetic analyses indicate that Latin Americans trace their ancestry mainly to the intermixing (admixture) of Native Americans, Europeans and Sub-Saharan Africans. Using novel haplotype-based methods, here we infer sub-continental ancestry in over 6,500 Latin Americans and evaluate the impact of regional ancestry variation on physical appearance. We find that Native American ancestry components in Latin Americans correspond geographically to the present-day genetic structure of Native groups, and that sources of non-Native ancestry, and admixture timings, match documented migratory flows. We also detect South/East Mediterranean ancestry across Latin America, probably stemming mostly from the clandestine colonial migration of Christian converts of non-European origin (Conversos). Furthermore, we find that ancestry related to highland (Central Andean) versus lowland (Mapuche) Natives is associated with variation in facial features, particularly nose morphology, and detect significant differences in allele frequencies between these groups at loci previously associated with nose morphology in this sample.Instituto Multidisciplinario de Biología Celula

Radiología aplicada al estudio de materiales conquiliológicos

El restaurador está en íntima relación con materiales biológicos que van desde la madera hasta secreciones tisulares como las conchas. Existen ejemplos de la utilización de la ciencia radiológica como apoyo durante el proceso de restauración de objetos biológicos como la madera (Lang, 1997), textiles (O’Connor, 2007), hueso (Chhem y Brothwell, 2008); pero específicamente en el tema de este capítulo, los materiales malacológicos, existen pocos ejemplos documentados en la bibliografía.Fil: Quinto Sanchez, Mirsha Emmanuel. Universidad Nacional Autonoma de Mexico. Instituto de Investigaciones Antropologicas; México. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Bautista Martínez, Josefina. Instituto Nacional de Antropología e Historia; Méxic

The relationship between facial shape asymmetry and attractiveness in mexican students

Objectives: It has been postulated that symmetric faces are considered more attractive than asymmetric ones because symmetry may signal high quality due to developmental stability. However, other studies showed that both symmetric and slightly asymmetric faces are considered attractive. Here we aim to explore this discrepancy, beginning with the analysis of the normal prevalence of facial symmetry in a population as a necessary first step prior to any attractiveness assessment. Methods: We collected facial landmarks from two-dimensional digital images of a sample of Mexican individuals (280 females and 285 males aged 18–68 years) that were analyzed using geometric morphometric methods. Then, we chose a subsample of 100 photographs (50 females and 50 males aged 18–27 years) selected to represent a broad range of asymmetrical variation, in order to evaluate attractiveness using a sex-opposite test. Finally, we analyzed the linear correlation between attractiveness and asymmetry. Results: We found that every evaluated subject presents some degree of facial asymmetry, and that both fluctuating asymmetry and directional asymmetry were significant (P < 0.0001) components of total facial asymmetry. Fluctuating asymmetry was slightly associated with age (r 5 0.0858, P 5 0.0414) and there were no differences between geographical regions (P 5 0.413). Attractiveness was not correlated to levels of asymmetry in either sex (males: P 5 0.0973; females P 5 0.7415). Conclusions: Asymmetry was a prevalent feature in the present sample, and preferences for symmetric faces were not operating in the studied population. Am. J. Hum. Biol. 27:387–396, 2015.Fil: Farrera, Arodi. Universidad Nacional Autónoma de México; MéxicoFil: Villanueva, Maria. Universidad Nacional Autónoma de México; MéxicoFil: Quinto Sanchez, Mirsha Emmanuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; ArgentinaFil: Gonzalez Jose, Rolando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentin

The first human settlement of the New World: A closer look at craniofacial variation and evolution of early and late Holocene Native American groups

During its expansion across the globe, Homo sapiens successfully survived to major adaptive challenges as a species, inviting scientific research to plunge into the particularities of continental settlement dynamics. A recurrent paleoanthropological concern is about the understanding of the great deal of craniofacial diversity that evolved into the Americas, which includes a vector of continuum variation between a generalized morphology observed among humans groups leading the Out-of-Africa dispersion, and a derived set of craniofacial traits classically labeled as ?mongoloid? and that would have arise in Asia during the Holocene. Here, we use geometric morphometric techniques and multivariate statistics along with quantitative genetic approaches to look more closely into the human craniofacial evolutionary history during the Late PleistoceneeEarly Holocene from Asia and the New World. We detected significant signals of deviation of the neutral evolutionary expectations, suggesting an important action of non-stochastic evolution (e.g. natural selection, phenotypic plasticity) in the Americas. We also found further support to the Recurrent Gene Flow model that refers to an ancestral, founder population experiencing a standstill in Beringia, and exhibiting high within-group craniofacial variation. This original, internally variable stock would have been the ancestral source of variation that fuelled the subsequent local micro evolution of other derived phenotypic patterns, giving origin to the craniofacial diversity observed among Holocene Native American samples. © 2015 Elsevier Ltd and INQUA.Fil: de Azevedo, Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Quinto Sanchez, Mirsha Emmanuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Paschetta, Carolina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: González José, Rolando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentin

Photogrammetry: A "low-cost" method to reconstruct the three-dimensional form of small mammals

Over the last few years, the field of morphometrics has undergone a profound revolution. During this time, digital imaging technology has made great strides and 3D (three-dimensional) imaging technology has become increasingly available. Nonetheless, many studies of 3D structures still use 2D (two-dimensional) data, even when this may result in the loss of important information. This is particularly so in the study of small mammals, since devices with enough precision for the 3D digitisation of small objects are the most expensive. Thus, the development of low-cost methods aimed at recovering 3D shape from small mammals would be of great interest. Photogrammetry, which allows obtaining 3D data at lower cost than with other 3D techniques, has been widely used in disciplines like geomorphology or architecture. Recently, some studies have started to use photogrammetry to recreate 3D models of animal phenotypes but, to our knowledge, it has not been applied to the study of small mammals or other small vertebrates. In this context, the aim of this study was to test the suitability of photogrammetric techniques to obtain 3D landmarks from mouse skulls as a model system for small mammals. Shape and size of 3D models obtained with photogrammetric techniques were consistent among replicates, even when different sets of photographs were used. The linear measurements obtained from the 3D models were highly correlated with measurements obtained with callipers on actual crania, and differences between both sets of measures were smaller than those among individuals in most of the tested measures. These results show for the first time that photogrammetry is a precise technique for 3D form analysis of small mammals. Photogrammetry also proved to be accurate for obtaining linear measurements between 3D landmarks. However, further studies are needed to demonstrate whether this technique is also accurate at recreating 3D shapes.Fil: Muñoz Muñoz, F.. Universitat Autònoma de Barcelona; EspañaFil: Quinto Sanchez, Mirsha Emmanuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; ArgentinaFil: Martinez Vargas, J.. Universitat Autònoma de Barcelona; EspañaFil: Gonzalez-Jose, Rolando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Ciencias Sociales y Humanas; ArgentinaII Iberian Symposium on geometric morphometricsMadridEspañaTransmitting ScienceUniversidad Autónoma de MadridInstitut Català de Paleontologia Miquel Crusafon