Castores: ¿un riesgo de invasión que inquieta a la Patagonia norte?

Las especies exóticas invasoras constituyen una de las amenazas más serias para la biodiversidad, siendo la segunda causa de extinción de especies, precedida tan sólo por la pérdida de hábitat. La introducción del castor en Tierra del ruego hace setenta años, ha sido probablemente el mayor cambio experimentado por los bosques y cuencas fueguinas. Si bien la mayoría de las especies introducidas no se establece de manera permanente o tiene muy pocos efectos sobre los ecosistemas, muchas otras especies sí lo hacen y su impacto generalmente resulta perjudicial, aunque puede ser sumamente variable según el ambiente. Son estas últimas especies las que en la mayoría de los casos se transforman en invasoras, tal como ocurrió con la introducción del castor (Castor canadensis) en Tierra del ruego.Fil: Fasanella, Mariana. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Patagonia Norte. Instituto de Investigación en Biodiversidad y Medioambiente; ArgentinaFil: Lizarralde, Marta Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentin

Néstor O. Bianchi (1931-2023) : Obituario

Semblanza biográfica de Néstor O. Bianchi (1931-2023).Asociación de Antropología Biológica Argentin

Historical demography and spatial genetic structure of the subterranean rodent <i>Ctenomys magellanicus</i> in Tierra del Fuego (Argentina)

Ctenomys (tuco-tuco) is the most numerous genus of South American subterranean rodents and one of the most genetically diverse clades of mammals known. In particular, the genus constitutes a very interesting model for evolutionary studies of genetic divergence and conservation. Ctenomys magellanicus is the southernmost species of the group and the only one living in Isla Grande de Tierra del Fuego (Argentina). This species presents two chromosomal forms (Cm34 and Cm36) fragmented into demes distributed from the north region (steppe) to the south region (ecotone) of the island, respectively; no hybrids or overlapping areas were detected. To study the historical demography and the spatial genetic structure of the C.magellanicus population we used mitochondrial DNA (mtDNA) (D-loop and cytochrome b) and microsatellite loci. Nine mtDNA haplotypes were identified, three of them belonging to the north and the other six to the south. Shared haplotypes between regions were not detected. mtDNA and microsatellite genotypes showed a marked pattern of population structure with low values of genetic flow between regions. The south is made up of small populations or isolated demes making up an endogamic metapopulation with unique alleles and haplotypes. Also, the results suggest a northward expansion process starting from an ancestral haplotype from the south. That population might have lived at a refuge through the adverse Pleistocene environmental conditions that took place at Tierra del Fuego. Results of this study are relevant to the conservation of C.magellanicus, suggesting that each region (north and south) might be considered as an Evolutionarily Significant Unit.Centro Regional de Estudios Genómico

Actinopterygii, Siluriformes, Loricariidae, <i>Hypostomus aspilogaster</i> (Cope, 1894) : Distribution extension and first record for Argentina

The present work extends to Argentina the distribution of Hypostomus aspilogaster originally described from Uruguay River in southern Brazil. The examined specimens were sampled in the stream Mandisoví Grande, affluent of Uruguay River in Entre Ríos province, and in Punta Lara, from Río de la Plata basin, in Buenos Aires province, Argentina. This represents the first country record for this species.Facultad de Ciencias Naturales y Muse

Actinopterygii, Siluriformes, Loricariidae, Hypostomus aspilogaster (Cope, 1894). Distribution extension and first record for Argentina

The present work extends to Argentina the distribution of Hypostomus aspilogaster originally described from Uruguay River in southern Brazil. The examined specimens were sampled in the stream Mandisoví Grande, affluent of Uruguay River in Entre Ríos province, and in Punta Lara, from Río de la Plata basin, in Buenos Aires province, Argentina. This represents the first country record for this species. © 2011 Check List and Authors.Fil: Cardoso, Yamila Paula. Universidad Nacional de La Plata. Centro Regional de Estudios Genómicos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Brancolini, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; ArgentinaFil: Protogino, Lucila Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; ArgentinaFil: Lizarralde, Marta Susana. Universidad Nacional de La Plata. Centro Regional de Estudios Genómicos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Evolutionary Genetics of Invasive Mammal Species Introduced in Argentina

Evolutionary genetics of invasive species has been unexplored in Argentina. Invasive alienspecies (IAS) have a wide geographical distribution, characteristic life cycles and great abilityto adapt, establish and spread in a new environment. Recent advances in novel moleculartechnologies, the use of higher resolution genetic markers, and the research development ongenetic variation of invasive species consolidated the importance of genetic aspects in theinvasion process. Undoubtedly, the growing concern for the disturbances generated by invasivespecies on biodiversity and functioning of ecosystems was also determinant for theinclusion of the Invasion Biology within the broad field of Evolutionary Biology includingrelevant examples that address the evolutionary genetic aspects of biological invasions. Recentstudies suggest that the invasion success of many species depends on their ability torespond to natural selection. Although the number of invasive species registered in Argentinafar exceeds 600, little research has been done on invasive mammal species and only fiveof them were hitherto genetically analyzed. Presuming that invasion genetics is incorporatedinto the agenda of control and management organizations, it would allow integrating theecological, genetic, and evolutionary biology aspects for knowledge of invasive specieswidely distributed in Argentina. The objective of this article is to highlight the importanceof evaluating the genetic structure of invasive species for their management and to informabout the invasive species of mammals that were introduced in Argentina and have been orare being analyzed genetically.Centro Regional de Estudios Genómico

Evolutionary Genetics of Invasive Mammal Species Introduced in Argentina

Evolutionary genetics of invasive species has been unexplored in Argentina. Invasive alienspecies (IAS) have a wide geographical distribution, characteristic life cycles and great abilityto adapt, establish and spread in a new environment. Recent advances in novel moleculartechnologies, the use of higher resolution genetic markers, and the research development ongenetic variation of invasive species consolidated the importance of genetic aspects in theinvasion process. Undoubtedly, the growing concern for the disturbances generated by invasivespecies on biodiversity and functioning of ecosystems was also determinant for theinclusion of the Invasion Biology within the broad field of Evolutionary Biology includingrelevant examples that address the evolutionary genetic aspects of biological invasions. Recentstudies suggest that the invasion success of many species depends on their ability torespond to natural selection. Although the number of invasive species registered in Argentinafar exceeds 600, little research has been done on invasive mammal species and only fiveof them were hitherto genetically analyzed. Presuming that invasion genetics is incorporatedinto the agenda of control and management organizations, it would allow integrating theecological, genetic, and evolutionary biology aspects for knowledge of invasive specieswidely distributed in Argentina. The objective of this article is to highlight the importanceof evaluating the genetic structure of invasive species for their management and to informabout the invasive species of mammals that were introduced in Argentina and have been orare being analyzed genetically.Fil: Lizarralde, Marta Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina. Universidad Nacional de La Plata. Centro Regional de Estudios Genómicos; ArgentinaFil: Fasanella, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Laboratorio de Ecotono; ArgentinaFil: Poljak, Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Laboratorio de Ecotono; Argentina. Universidad Nacional de Tierra del Fuego. Instituto de Ciencias Polares, Recursos Naturales y Ambiente; ArgentinaFil: Gabrielli, Magali. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata. Centro Regional de Estudios Genómicos; ArgentinaFil: Sánchez, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Laboratorio de Ecotono; Argentina. Universidad Nacional de Tierra del Fuego. Instituto de Ciencias Polares, Recursos Naturales y Ambiente; Argentin

Phylogeographic pattern of jenynsia multidentata (Cyprinodontiformes: Anablepidae) in the southern boundary of the Brazilian subregion, Argentina

The Atlantic drainage basins are located in the southern Pampean area, in the southernmost part of the Brazilian subregion. Tectonic and paleoclimatic phenomena, occurring during the Quaternary, have currently isolated these basins from the present hydrographic system. Their ichthyofaunal composition is similar to that of hydric systems located further northward. Jenynsia multidentata is a species with wide distribution in the Atlantic drainage basins, as well as in those Northern basins. Here we investigated the phylogeographic pattern of Jenynsia multidentata and analyzed its relationships with the paleoclimatic and geologic history of the region. The analysis of the population's assemblage showed moderate genetic diversity, demographic equilibrium and marked genetic structure in the populations that occupy the extremes of the distributional range. The populations in the center of the range did not present genetic diversity, sharing a single haplotype. These results allow inferring that the presence of Jenynsia multidentata in the area results from historical demographic processes that are independent but complementary. In turn, these processes could arise from paleoclimatic changes occurred during the Quaternary.Las cuencas de pendiente atlántica del área pampeana Austral son el límite meridional de la subregión Brasílica. Fenómenos tectónicos y paleoclimáticos ocurridos durante el Cuaternario han dejado aisladas a estas cuencas del diseño hidrográfico actual. La composición íctica de estás cuencas es similar a la de los sistemas hídricos ubicados más al norte. Jenynsia multidentata es una especie con un amplia distribución en las cuencas de pendiente atlántica, como así también, en las cuencas ubicadas al norte. En el presente trabajo se investigó el patrón filogeográfico de Jenynsia multidentata, y se examinó la relación entre este patrón y la historia paleoclimática y geológica de la región. En el análisis del conjunto de poblaciones se encontró evidencia de una moderada diversidad genética, equilibrio demográfico, y una marcada estructura poblacional, en las poblaciones que ocupan los extremos de la distribución. Mientras que en las poblaciones que ocupan el centro de la distribución no se encontró diversidad genética presentando un único haplotipo. De los resultados obtenidos se infiere que la presencia de Jenynsia multidentata en el área es el resultado de procesos demográficos históricos independientes pero complementarios. A su vez, estos procesos podrían surgir de los cambios paleoclimáticos ocurridos durante el Cuaternario.Fil: Bruno, María Cecilia. Universidad Nacional de La Plata. Centro Regional de Estudios Genómicos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Cientifico Tecnológico La Plata; ArgentinaFil: Casciotta, Jorge Rafael. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Zoología de Vertebrados. Sección Ictiología; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; ArgentinaFil: Almirón, Adriana Edith. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Cientifico Tecnológico La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Zoología de Vertebrados. Sección Ictiología; ArgentinaFil: Lizarralde, Marta Susana. Universidad Nacional de La Plata. Centro Regional de Estudios Genómicos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Cientifico Tecnológico La Plata; Argentin

Phylogeographic pattern of <i>Jenynsia multidentata</i> (Cyprinodontiformes: Anablepidae) in the southern boundary of the Brazilian subregion, Argentina

The Atlantic drainage basins are located in the southern Pampean area, in the southernmost part of the Brazilian subregion. Tectonic and paleoclimatic phenomena, occurring during the Quaternary, have currently isolated these basins from the present hydrographic system. Their ichthyofaunal composition is similar to that of hydric systems located further northward. Jenynsia multidentata is a species with wide distribution in the Atlantic drainage basins, as well as in those Northern basins. Here we investigated the phylogeographic pattern of Jenynsia multidentata and analyzed its relationships with the paleoclimatic and geologic history of the region. The analysis of the population's assemblage showed moderate genetic diversity, demographic equilibrium and marked genetic structure in the populations that occupy the extremes of the distributional range. The populations in the center of the range did not present genetic diversity, sharing a single haplotype. These results allow inferring that the presence of Jenynsia multidentata in the area results from historical demographic processes that are independent but complementary. In turn, these processes could arise from paleoclimatic changes occurred during the Quaternary.Facultad de Ciencias Naturales y Muse

Phylogeographic pattern of <i>Jenynsia multidentata</i> (Cyprinodontiformes: Anablepidae) in the southern boundary of the Brazilian subregion, Argentina

The Atlantic drainage basins are located in the southern Pampean area, in the southernmost part of the Brazilian subregion. Tectonic and paleoclimatic phenomena, occurring during the Quaternary, have currently isolated these basins from the present hydrographic system. Their ichthyofaunal composition is similar to that of hydric systems located further northward. Jenynsia multidentata is a species with wide distribution in the Atlantic drainage basins, as well as in those Northern basins. Here we investigated the phylogeographic pattern of Jenynsia multidentata and analyzed its relationships with the paleoclimatic and geologic history of the region. The analysis of the population's assemblage showed moderate genetic diversity, demographic equilibrium and marked genetic structure in the populations that occupy the extremes of the distributional range. The populations in the center of the range did not present genetic diversity, sharing a single haplotype. These results allow inferring that the presence of Jenynsia multidentata in the area results from historical demographic processes that are independent but complementary. In turn, these processes could arise from paleoclimatic changes occurred during the Quaternary.Facultad de Ciencias Naturales y Muse