Universidad Champagnat

Abstract We reassess the taxonomy of the problematic taxon “ Podocnemis ” argentinensis from the Maíz Gordo Formation (late Paleocene) at Quebrada Queñoal (type locality), Departamento de Humahuaca, Jujuy province, Argentina. This plastron-based species was initially named as a member of the genus Podocnemis ( Podocnemididae ) based on the holotype and one referred specimen. Considering the dubious generic assignment of the holotype of “ Podocnemis ” argentinensis , we performed a thorough revision of the morphological characters of this taxon, based on the holotype and previously undescribed specimens from the same lithostratigraphic unit in the Casa Grande-Vizcarra river area (western flank of the Mal Paso Range, Tres Cruces Sub-basin) in Jujuy province, Argentina. The new referred specimens include a collection of shells found in association with one skull from Quebrada del Agujero, as well as some shells from Quebrada del Puesto in the same region. Comparison between the extended hypodigm of “ Podocnemis ” argentinensis and other podocnemidids suggests the assignment of this species to a new generic entity, based on the presence of a short preorbital skull portion with steeply curved prefrontal bones, both exoccipital bones with a dorso-medial process restricting the dorsal part of the foramen magnum to a narrow cleft, lateral orbits, absence of an interorbital groove, high maxillae, a large vomer and the generalized gular, extragular and humeral scute pattern. We included this species in a phylogenetic analysis to assess its relationships with other pelomedusoid turtles. It is recovered as the sister taxon of Gestemys powelli , with which it shares the following four synapomorphies: foramen posterius canalis carotici interni outside the basisphenoid, long basioccipital, reduced nuchal embayment and dorsoventral flattening of the shell. The clade including “ Podocnemis ” argentinensis and Gestemys constitutes a Paleogene Argentinean lineage which is more closely related to Erymnochelyinae and Peltocephalinae than to Podocnemidinae , a position supported by a more covered adductor fossa and a large anterior opening of the cavum pterygoidei.

Resumen La personalidad proactiva es una tendencia relativamente estable a generar cambios en el ambiente para mejorarlo. El objetivo de este estudio fue traducir, adaptar y validar la Escala de Personalidad Proactiva de Bateman y Crant en Argentina. Se empleó un diseño empírico-instrumental transversal sobre una muestra no probabilística de 465 trabajadores (54% mujeres; X edad = 34,5 años; DT edad = 12,94). Análisis factoriales exploratorios y confirmatorios indicaron la adecuación de un modelo unifactorial con seis variables observables (SBχ2= 2,01; GFI= 0,98; CFI= 0,95; RMSEA= 0,04, AIC= 42,03; ω = 0,82; CR= 0,80). Las correlaciones positivas entre personalidad proactiva, comportamientos proactivos, satisfacción e implicación laboral indicaron apropiada evidencia de validez de relación con variables externas. Los resultados obtenidos muestran que la versión argentina del instrumento presenta adecuadas propiedades psicométricas para el contexto laboral.

El trabajo explora cuán estables fueron las estrategias humanas una vez que las poblaciones indígenas del centro-occidente argentino incorporaron cultígenos. Asimismo, evalúa si una vez incorporado el consumo de plantas domésticas, las estrategias fueron, o no, progresivamente apoyándose más sobre la producción y consumo de las mismas. El estudio compara tres sitios con restos humanos (Jaime Prats-1, Rincón del Atuel-1 y Cañada Seca-1) localizados entre sí a una distancia máxima de 40 km y en un valle considerado como el límite sur de la agricultura andina prehispánica. Estos sitios, que presentan una continuidad temporal, abarcan desde ca. 1900 (300 años posterior al registro inicial de las plantas domésticas en la región) a ca. 1400 años aP. Se comparan datos de isótopos estables (13C,15N,18O), morfometría craneal, mandibular y dental, junto a información contextual arqueológica. El sitio más antiguo, Jaime Prats-1, muestra semejanzas isotópicas y morfológicas con Cañada Seca-1, el más reciente, a pesar de no ser continuos en el tiempo. Ambos se diferencian de Rincón del Atuel-1, que temporalmente se intercala entre los dos. Los resultados señalan una mayor importancia del maíz en Rincón del Atuel-1, junto a una menor movilidad residencial, aunque en ninguno de los casos este recurso habría contribuido más del 30% a la dieta. Los sistemas humanos que ocuparon la frontera agrícola en estos primeros 500 años de uso de plantas domésticas muestran una alta variabilidad en su organización, sin cruzar umbrales que impidan retornar a sistemas de baja producción.

Fil: Vennari, Veronica Vanesa. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Mendoza. Instituto Argentino de Nivologia, Glaciologia y Ciencias Ambientales. Museo de Historia Natural de San Rafael - Ianigla | Provincia de Mendoza. Instituto Argentino de Nivologia, Glaciologia y Ciencias Ambientales. Museo de Historia Natural de San Rafael - Ianigla | Universidad Nacional de Cuyo. Instituto Argentino de Nivologia, Glaciologia y Ciencias Ambientales. Museo de Historia Natural de San Rafael - Ianigla; Argentina

The Puesto Viejo Group crops out in the San Rafael Block, southwest Mendoza, Argentina. This group is an important unit for the knowledge theTriassic faunas. It is composed of basal Quebrada de los Fósiles Formation (QF) overlying by the Río Seco de la Quebrada Formation (RSQ). In this study, we report tetrapod remains from the RSQ Formation that includes, until now, exclusively therapsids. Non-mammalian therapsids predominated in terrestrial ecosystems during the Late Paleozoic and Early Mesozoic. Although cynodonts and dicynodonts have been studied from several perspectives, the relation between taxa and sedimentary context has been scarcely documented. This study is aimed to elucidate the diagenesis of tetrapods from the Puesto Viejo Group and its relation to depositional environment. Diagenetic features of therapsid bones from the RSQ Formation were analyzed through thin sections to interpret the degree of taphonomic alteration. Diagenetic processes inferred include substitution; fracturing; brittle deformation and different permineralization events. Combined analyses through scanning electron microscopy; energy-dispersive X-ray spectrometry (SEM-EDX); X-ray diffractometry (XRD) and petrographic studies reveals the substitution of hydroxyapatite by francolite. The presence of fluorine in some samples suggests a link between the elemental composition and depositional environments: floodplain and crevasse splay. Permineralization stages include infilling of vascular canals, trabeculae and fractures with iron oxides and iron carbonate minerals during the burial history. This contribution represents a relevant approach to elucidate the relation between diagenesis on tetrapods and their paleoenvironments, as exemplified in this case study from the Puesto Viejo Group during the Upper Triassic.

The site El Indígeno contains the greatest known concentration of hunter-gatherer residential features in the southern Andes. Located at 3,300 m asl in a meadow in the Cordillera of west-central Argentina, the site is notable for its 133 habitation structures, that—when considered along with the other characteristics of the site—represent an anomalous but perhaps not entirely unexpected adaptation to the highest altitude environment in the region. Based on radiocarbon dating and artifact typologies, the site was occupied between ca. 800 and 1500 B.P. It consequently represents the latest step in the indigenous colonization of what is arguably the most marginal environment in the region. This chronology suggests that the site was occupied when nearby lowland regions were under their most intensive use and during a time when new resources were incorporated into the high-altitude hunter-gatherer diet. In this article I report on research conducted at El Indigeno and compare the results of these studies to the regional record, ultimately concluding that regional population increase affiliated with the spread of increasingly complex socioeconomic systems most parsimoniously explains the intensive occupation of this large, high-altitude hunter-gatherer site.

Background. Condorchelys antiqua is a stem turtle previously described from the Queso Rallado Locality, Cañadón Asfalto Formation (Early-Middle Jurassic), Chubut, Argentina. In 2014 a skull (MPEF-PV 10900) and an articulated shell with associated postcranial remains (MPEF-PV 10884) of C. antiqua were discovered in the mentioned locality. Methods. The new specimens have been prepared by L. Reiner (technician at the Museo Egidio Feruglio) and then studied using the regular paleontological methodology (e.g., direct observations and under the microscope, photography, and drawings). The new data provided by these two specimens, plus some other isolated remains that were re-prepared, allowed us to score a 25% more of the characters of C. antiqua in the most complete up to date matrix for Mesozoic turtles. The matrix was build in Mesquite and analyzed under maximum parsimony in TNT. We performed two rounds of Tree Bisection Reconnection and calculated a strict consensus. Branch supports were provided using bootstrap, jackknife, and Bremer support. Results. We regard the specimen MPEF-PV 10900 as represented by the basicranium and some previously unknown skull bones like the maxilla, frontal, parietal, and postorbital. This specimen also shows that there were no teeth in the pterygoid of C. antiqua. On the other hand, specimen MPEF-PV 10884 is an almost complete carapace and plastron with 4 thoracic vertebrae and ribs, scapular and pelvic girdles, humerus, left radius, femur, tibia, fibula, 2 metatarsal/carpals, 2 phalanges, 1 ungual phalanx and 1 chevron bone. The preliminary cladistic analysis resulted in 750 most parsimonious trees of 893 steps. The result of the analysis corroborates the position of C. antiqua as a stem turtle more derived than the Triassic and Australochelys africanus. Condorchelys antiqua is recovered in a polytomy together with other early-middle Jurassic turtles (e.g., Kayentachelys aprix and Indochelys spatulata) and the clade formed by the remaining turtles. Discussion. Although many new characters have been scored for C. antiqua in the phylogenetic analysis, this new information did not resolved the phylogenetic position for this taxon. We consider that more information about I. spatulata and K. aprix could help to better understand the relationships among these basal taxa. On the other hand, these new specimens of C. antiqua bring valuable information to decipher the anatomy of the poorly known non-shell postcranial elements of these Early to Middle Jurassic stem turtles. In light of the recently suggested aquatic preferences of C. antiqua, the next step on this research would be to explore other adaptations to the aquatic environment using postcranial elements, particularly the limb bones.

Previous researches have examined the zooarchaeological record to understand changes in human diet in central western Argentina through time. This research has focused on variations in the relative abundance of large prey in archaeofaunal contexts. The observed changes were explained by a decrease in residential mobility, forced by both the intensification in the use of resources and the introduction of the first domesticated plants ca. 2000 years bp. In this paper, we revised archaeofaunal interpretations by taking into account zooarchaeological assemblages and human isotope records within the biogeographical distributions of prey in the region. Our results demonstrate that faunal diversity in zooarchaeological assemblages has a stronger correlation with the natural distribution of resources (especially with altitude) than with chronology, as was proposed previously. However, archaeofaunal information, including human isotopic data, suggests that a decrease in residential mobility, postulated in a previous paper, took place, modifying the expected diversity distribution throughout the landscape. Copyright © 2013 John Wiley & Sons, Ltd.