Causas y contrastes en la distribución presente y pasada del tiburón blanco (Lamniformes: Carcharodon carcharias) costa afuera de Sud América sudoriental

The great white shark is a cosmopolitan temperate marine species which is rare in Argentina, Uruguay, and Brazil today. Several publications include the white shark as inhabiting Patagonian waters. However, there is no recent or fossil record of the white shark south of S 38°in-line 30′ in the southwestern Atlantic. A tooth found in Quaternary sediments at Pehuencó (S 38°in-line 56′), southern Buenos Aires province, is the southernmost occurrence of the species in the southwestern Atlantic. The occurrence of C. carcharias in the Buenos Aires province is another confirmation that the Argentine biogeographic province extends to the south of the Río de la Plata. The present extremely scarce record indicates that there are not permanent living populations in the South American Atlantic coast but occasional transient individuals. However, the abundant fossil and archaeological record suggests that it was much more common in southwestern Atlantic during the late Pleistocene and Holocene than today. This drop in abundance is here mostly attributed to the massive extermination of pinnipeds and cetaceans during the XIXth and XXth centuries. Patagonian waters, where marine mammals are relatively abundant even today, might be too cold for the species which is mostly encountered between 15-23°in-line C. Besides, another important predator, the killer whale, which also feeds on marine mammals, is frequently found in these waters. Consequently, available evidence suggests that unrestricted hunting of pinnipeds and cetaceans also decimated another animal, a fish.El tiburón blanco es una especie cosmopolita en mares templados y que es rara actualmente en Argentina, Uruguay y Brasil. Varias publicaciones incluyen a tiburón blanco como habitando aguas patagónicas. Sin embargo, no hay registro actual o fósil al sur de S 38° 30' en el Atlántico sudoccidental. Un diente hallado en sedimentos cuaternarios en Pehuencó (S 38° 56'), sur de la provincia de Buenos Aires es el registro más austral en el Atlántico sudoccidental. El registro actual de C. carcharías en la provincia de Buenos Aires es otra confirmación de que la provincia biogeográfica Argentina se extiende al sur del Río de la Plata. El extremadamente escaso registro actual indica que no hay poblaciones permanentes en la costa atlántica sudamericana sino individuos aislados. Sin embargo, el abundante registro fósil y arqueológico sugiere que fue mucho más común durante el Pleistoceno tardío y el Holoceno. La disminución de la abundancia es aquí principalmente atribuida al exterminio masivo de pinípedos y cetáceos en los siglos XIXth y XX.th Las aguas patagónicas, donde todavía hay abundancia de mamíferos marinos podrían ser demasiado frías para la especie, que es más frecuente entre 15° y 23 °C. Por otra parte, la orea, que también se alimenta de mamíferos marinos, es frecuente en esas aguas. Consecuentemente, la evidencia disponible sugiere que la caza irrestricta de pinípedos y cetáceos eliminó otro animal, un pez.Facultad de Ciencias Naturales y Muse

Causas y contrastes en la distribución presente y pasada del tiburón blanco (Lamniformes: Carcharodon carcharias) costa afuera de Sud América sudoriental

The great white shark is a cosmopolitan temperate marine species which is rare in Argentina, Uruguay, and Brazil today. Several publications include the white shark as inhabiting Patagonian waters. However, there is no recent or fossil record of the white shark south of S 38°in-line 30′ in the southwestern Atlantic. A tooth found in Quaternary sediments at Pehuencó (S 38°in-line 56′), southern Buenos Aires province, is the southernmost occurrence of the species in the southwestern Atlantic. The occurrence of C. carcharias in the Buenos Aires province is another confirmation that the Argentine biogeographic province extends to the south of the Río de la Plata. The present extremely scarce record indicates that there are not permanent living populations in the South American Atlantic coast but occasional transient individuals. However, the abundant fossil and archaeological record suggests that it was much more common in southwestern Atlantic during the late Pleistocene and Holocene than today. This drop in abundance is here mostly attributed to the massive extermination of pinnipeds and cetaceans during the XIXth and XXth centuries. Patagonian waters, where marine mammals are relatively abundant even today, might be too cold for the species which is mostly encountered between 15-23°in-line C. Besides, another important predator, the killer whale, which also feeds on marine mammals, is frequently found in these waters. Consequently, available evidence suggests that unrestricted hunting of pinnipeds and cetaceans also decimated another animal, a fish.El tiburón blanco es una especie cosmopolita en mares templados y que es rara actualmente en Argentina, Uruguay y Brasil. Varias publicaciones incluyen a tiburón blanco como habitando aguas patagónicas. Sin embargo, no hay registro actual o fósil al sur de S 38° 30' en el Atlántico sudoccidental. Un diente hallado en sedimentos cuaternarios en Pehuencó (S 38° 56'), sur de la provincia de Buenos Aires es el registro más austral en el Atlántico sudoccidental. El registro actual de C. carcharías en la provincia de Buenos Aires es otra confirmación de que la provincia biogeográfica Argentina se extiende al sur del Río de la Plata. El extremadamente escaso registro actual indica que no hay poblaciones permanentes en la costa atlántica sudamericana sino individuos aislados. Sin embargo, el abundante registro fósil y arqueológico sugiere que fue mucho más común durante el Pleistoceno tardío y el Holoceno. La disminución de la abundancia es aquí principalmente atribuida al exterminio masivo de pinípedos y cetáceos en los siglos XIXth y XX.th Las aguas patagónicas, donde todavía hay abundancia de mamíferos marinos podrían ser demasiado frías para la especie, que es más frecuente entre 15° y 23 °C. Por otra parte, la orea, que también se alimenta de mamíferos marinos, es frecuente en esas aguas. Consecuentemente, la evidencia disponible sugiere que la caza irrestricta de pinípedos y cetáceos eliminó otro animal, un pez.Facultad de Ciencias Naturales y Muse

Cowrie snails (Mollusca, gastropoda) in Tell el-Ghaba, a third intermediate to late period settlement in North Sinai, Egypt : comments on their use

Fil: Cione, Alberto Luis. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; ArgentinaFil: Pérez, Leandro Martín. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; ArgentinaFil: Bacquerisse, Cristina. Universidad de Buenos Aires; Argentin

Redescription of the Eocene catfish Bachmannia chubutensis (Teleostei: Bachmanniidae) of southern South America

The Siluriformes constitutes an important monophyletic ostariophysan group of mainly freshwater fishes that occurs in almost all continents. They are extremely abundant and diverse in South America, where the oldest otophysans and siluriforms occur. We restudied two putative catfish species from the early Eocene lacustrine Tufolitas Laguna del Hunco of northwestern Patagonia, Argentina, concluding that Arius argentinus Dolgopol, 1941, is a junior synonym of Bachmannia chubutensis Dolgopol, 1941. Phylogenetic analyses were performed to show the relationships of B. chubutensis, which appears as the sister group of Diplomystes. Bachmannia chubutensis is one of the most primitive catfishes known and we based on it a new family. The family is clearly diagnosed by the presence of a anterior ventrolateral expansion of cleithrum, short maxilla with two rows of teeth, double-headed autopalatine, accessory tooth plates, very huge teeth, supraoccipital process long and acute, first and fifth vertebrae not joined to complex vertebra, neural arch of fifth and sixth vertebrae very well developed, enlarged supraneural 5, suture between ceratohyal and epihyal without interdigitations, suture between contralateral cleithra and coracoids without interdigitations, six hypurals. Individuals of B. chubutensis inhabited lakes and were preserved into fine-grained, laminated fall-out and reworked pyroclastic debris inside a caldera.Fil: Azpelicueta, María De Las Mercedes. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Departamento Científico Zoología Vertebrados; ArgentinaFil: Cione, Alberto Luis. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentin

Sea and continental turtles and crocodiles in a site of the Third Intermediate to Late Period Settlement in northern Sinai, Egypt

Fil: Cione, Alberto Luis. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; ArgentinaFil: De la Fuente, Marcelo Saúl. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; Argentin

Effects of add-on ultramicronized n-palmitol ethanol amide in patients suffering of migraine with aura. a pilot study

Background: Palmitoyl ethanol amide (PEA) is an endogenously produced substance showing anti-nociceptive effect through both receptor and non-receptor mediated effects at the level of different cellular and tissue sites. This study showed the results of a single blind study that was conducted to evaluate both the safety and the efficacy of ultramicronized PEA (umPEA; 1,200 mg/day) for up 90 days in patients suffering of Migraine with Aura (MA) treated with NSAIDs. Methods: A total of 20 patients, 8 male (33-56-years, average 41.4 ± 7.8) and 12 female (19-61-years, average 38.5 ± 11.9) with MA were admitted to our observation and diagnosed according to ICHD-3 criteria, they received umPEA (1,200 mg/day) in combination with NSAIDs for up to 90 days. They were revaluated at 30, 60, and 90 days after treatment. Results: umPEA administration induced a statistically significant and time dependent pain relief. In particular, these effects were evident at 60 days (male P = 0.01189; female P = < 0.01) and they lasted until the end of the study (male P = 0.0066; female P = 0.01473). Conclusion: Although further studies are needed, our findings indicate that in patients suffering of MA treatment with umPEA had good efficacy and safety which candidate this compound as a therapeutic tool in pain migraine management

Did the megafauna range to 4300 BP in South America?

A date of 4300 ± 90 BP for extinct megafauna in Argentina is discussed. The fossil remains come from the Guerrero Member (area) of the Luján Formation near the city of Luján, Buenos Aires Province. The age of the top of the Guerrero Member is constrained by more than 60 radiocarbon dates obtained from the overlying Río Salado Member of Luján Formation, Las Escobas Formation, and Puesto Callejón Viejo Soil, most of them older than 4300 BP. In view of its low collagen content, the 14C measurement of bone sample from Luján should not be accepted uncritically. Because of the poor bone preservation and the possible introduction of "young" contaminants that were not completely eliminated, the 14C date of 4300 ± 90 BP is not reliable. Both biostratigraphic and 14C dating evidence indicates that the date of 4300 BP for the last representative of extinct megafauna in South America is unsupported.Facultad de Ciencias Naturales y Muse

Conceito de Formação Geográfica: Teoria e método

The concept of "geographical formation" is postulated as a necessary theoretical and methodological overcoming of the concept of "geographical space" to designate and address the objects and problems of geography, in order to simultaneously respond to epistemological and practical demands.Se postula el concepto formación geográfica como necesaria superación teórica y metodológica del concepto de espacio geográfico para designar y abordar los objetos y problemas de la geografía, a los fines de responder simultáneamente a las demandas epistemológicas y prácticas, entre ellas las implicadas en los procesos de enseñanza.O conceito de “formação geográfica” é postulado como uma superação teórica e metodológica necessária do conceito de “espaço geográfico” para designar e abordar os objetos e problemas da geografia, de forma a responder simultaneamente às exigências epistemológicas e práticas

Did the megafauna range to 4300 BP in South America?

A date of 4300 ± 90 BP for extinct megafauna in Argentina is discussed. The fossil remains come from the Guerrero Member (area) of the Luján Formation near the city of Luján, Buenos Aires Province. The age of the top of the Guerrero Member is constrained by more than 60 radiocarbon dates obtained from the overlying Río Salado Member of Luján Formation, Las Escobas Formation, and Puesto Callejón Viejo Soil, most of them older than 4300 BP. In view of its low collagen content, the 14C measurement of bone sample from Luján should not be accepted uncritically. Because of the poor bone preservation and the possible introduction of "young" contaminants that were not completely eliminated, the 14C date of 4300 ± 90 BP is not reliable. Both biostratigraphic and 14C dating evidence indicates that the date of 4300 BP for the last representative of extinct megafauna in South America is unsupported.Facultad de Ciencias Naturales y Muse