Abstract:

How birds adapt to urban life is a key question in evolutionary and conservation biology since urbanisation is one of the major causes of habitat loss worldwide. Some species are able to deal with these anthropogenic changes but a shortage of nesting sites may preclude them from breeding in cities. We conducted a baseline survey of the cliff-nesting burrowing parrot Cyanoliseus patagonus around Bahía Blanca (Argentina), estimating a minimum total of 1,361 pairs breeding at 24 sites (colonies) in 2013. The species showed facultative colonial behaviour, colony size varying between 1 and 300 pairs. Most colonies (68%) and pairs (74%) occupied human-made substrates, mostly quarries but also water wells. Colony size was strongly correlated to the extent of both natural and anthropogenic nesting substrates, suggesting an ideal free distribution of pairs according to the availability of nesting resources. Anthropogenic substrates have certainly allowed population expansion in what is a rather flat landscape with a shortage of cliffs and ravines, as well as urban breeding by a large part (61%) of the surveyed population. This is currently one of the largest populations of burrowing parrots, a previously abundant species that is progressively threatened by persecution and nest poaching for the international pet trade.

Dado que la urbanización es una de las causas principales de pérdida de hábitat a escala mundial, resulta clave desde el punto de vista evolutivo y de conservación comprender cómo las aves se adaptan a vivir en este tipo de medios. Algunas especies son capaces de adaptarse al medio urbano, pero la escasez de lugares para nidificar puede impedir su reproducción. En este trabajo realizamos un seguimiento del loro barranquero Cyanoliseus patagonus en los alrededores de Bahía Blanca (Argentina), estimando una población reproductora mínima de 1.361 parejas distribuidas en 24 colonias en 2013. El tamaño de las colonias varió entre 1 y 300 parejas, mostrando un comportamiento colonial facultativo. La mayor parte de las colonias (68%) y de las parejas reproductoras (74%) ocuparon sustratos de origen humano, fundamentalmente canteras, aunque también se instalaron en pozos de agua. El tamaño de las colonias estuvo fuertemente correlacionado con el tamaño de los sustratos de nidificación, tanto naturales como artificiales, sugiriendo una distribución libre ideal de las parejas acorde con la disponibilidad de lugares para nidificar. Los sustratos de origen antrópico seguramente permitieron una expansión poblacional en un paisaje llano, con escasez de quebradas y barrancas, pero también una colonización del medio urbano por buena parte de la población reproductora censada (61%). Esta puede constituir ahora una de las mayores poblaciones de loros barranqueros del mundo, una especie que antaño fue abundante pero que se vio progresivamente amenazada por la persecución humana y su explotación para el comercio internacional de mascotas.

Author affiliation: Tella Escobedo, José Luis. Consejo Superior de Investigaciones Cientificas; España

Author affiliation: Canale, Antonela. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; Argentina

Author affiliation: Carrete, Martina. Consejo Superior de Investigaciones Cientificas; España. Universidad Pablo de Olavide; España. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Petracci, Pablo. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; Argentina

Author affiliation: Zalba, Sergio Martín. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Abstract:

Se denomina cantera al sitio donde se saca piedra, greda u otra sustancia análoga para obras varias. Las extracciones de minerales en las canteras, son consideradas un tipo de explotación minera de superficie. Las canteras pueden clasificarse de acuerdo al material que se extrae y su uso, y según su localización. La explotación en canteras, puede tener un alto impacto ambiental debido a que producen un cambio profundo y permanente en el paisaje y destruyen por completo el ecosistema preexistente.

A quarry is the site where stone, clay or another similar substance is extracted for various works. The quarrying of minerals in the quarries is considered a type of surface mining. The quarries can be classified according to the material that is extracted and its use, and according to its location. The exploitation in quarries, can have a high environmental impact because they produce a profound and permanent change in the landscape and completely destroy the pre-existing ecosystem.

Author affiliation: Roncallo, Luciana. Universidad Nacional de Río Negro. Sede Andina; Argentina.

Abstract:

The study of technological organization associated with hunter-gatherers groups has been one of the topics of greatest interest in the archaeological research of the Pampean region. In this sense, the aims of this paper were to interpret the role of the Cerro Largo Formation chert in the technological practices of human groups and to discuss how this rock was used and transported in the center of the Humid Pampa sub-region during the Late Holocene. We will present the techno-morphological analysis on chert artifacts recovered from Boca de la Sierra workshop in order to identify how this stone was used at the beginning of its exploitation. Then, we will compare and discuss diverse chaînes opérotoires on chert found in archaeological sites located at different distances from the sources. In Boca de la Sierra workshop, we recorded three initial forms of exploitation of the nodules. The Cerro Largo Formation chert had been transported from this workshop to other sites in the form of different kinds of partially and/or totally decorticated cores, nodules, large flakes, and possibly tools. In those sites located at a short distance from the quarry workshops (Empalme Querandíes 1 and Laguna La Barrancosa 2) we observed complete chaînes opérotoires organized through débitage, with low production of standardized blank and a high frequency of external flakes used as blank for the manufacture of different kinds of tools. In those sites located at a long distance from the quarry workshops (Laguna La Larga and Laguna Seca 2), we recorded chaînes opérotoires developed almost entirely. Even though some expedient tools are recorded, the greatest maximization in the use of Cerro Largo Formation chert is remarkable. The high proportion of standardized, small and shaped tools, the identification of exhausted cores, the use of a bipolar technique, and the presence of resharpening flake edges show a curated technological strategy. Finally, the presence of complete chaînes opérotoires close to the hills allow us to infer direct access to the outcrops and an easy acquisition of chert; whereas the features observed in the other sites indicate that the chert acquisition was done by specific trips or by social exchange and interaction networks with other groups.

Author affiliation: Barros, Maria Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Investigaciones Arqueológicas y Paleontológicas del Cuaternario Pampeano. Universidad Nacional del Centro de la Provincia de Buenos Aires. Investigaciones Arqueológicas y Paleontológicas del Cuaternario Pampeano; Argentina

Author affiliation: Messineo, Pablo Geronimo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Investigaciones Arqueológicas y Paleontológicas del Cuaternario Pampeano. Universidad Nacional del Centro de la Provincia de Buenos Aires. Investigaciones Arqueológicas y Paleontológicas del Cuaternario Pampeano; Argentina

Author affiliation: Colantonio, Maria Jose. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Sociales; Argentina

Abstract:

Many studies relate silica content in plants with internal or external factors; however, few works analyse the effect of these factors on the silicification of different cell types. In this study, we examined the effect of leaf section and leaf position, and environmental conditions on the percentages of silicified epidermal cells of a native Pampean panicoid grass, Bothriochloa laguroides D. C. Pilger. Two different environmental situations were selected for the collection of plants: a natural wetland and a quartzite quarry, located in the southeast Buenos Aires province, Argentina. Clarification and staining methodologies were applied so as to study the distribution of silicified cells in different sections of leaves of the plants collected. Two and three-factor anovas were applied to the data. Between 13% and 19% of total cells of the adaxial epidermis of leaf blades were silicified. Typical silica short cells were the largest contributor to total silicified cells (53-98%), while the second largest contributor was bulliform cells (0-30%). Percentages of total silicified cells were higher in superior than in inferior leaves, while values from leaf sections varied. When collection sites were compared, plants growing in Los Padres pond, where the silica content in soils is higher, had the higher percentage of silicified cells. Among all types of cell, bulliform cells showed differences in the proportion of silicified cells between leaf position and section and collection site. These results show that silica availability in soils is an important factor that conditions silica accumulation and overlaps with the transpiration effect. © 2011 German Botanical Society and The Royal Botanical Society of the Netherlands.

Author affiliation: Fernández Honaine, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Geología de Costas y del Cuaternario. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto de Geología de Costas y del Cuaternario; Argentina

Author affiliation: Osterrieth, Margarita Luisa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Geología de Costas y del Cuaternario. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto de Geología de Costas y del Cuaternario; Argentina

Abstract:

The present study is the first step in the elaboration of a regional base of lithic resources for an area located in the northeastern San Luis province, Argentina. Within this area lies the Estancia La Suiza archeological locality, near the hills of Sierra de la Estanzuela, where prehistoric quarry workshops have been identified. The main objective of this work was to explore the use of the different raw materials by prehistoric groups. The general geological setting of the hills of Sierra de la Estanzuela is described, and a distribution of raw material in the area is proposed. The principal sources of lithic material procurement representing the archeological record were identified, and lithic types were quantified and classified. Finally, the lithic material recovered from the Estancia La Suiza 2 quarry was characterized; the results show that the artifacts correspond to the earliest stages of production.

Author affiliation: Sario, Gisela Mariela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Instituto de Antropología de Córdoba; Argentina. Universidad Nacional de Cordoba. Facultad de Filosofia y Humanidades. Museo de Antropologia; Argentina