Search results for "Zoología"
showing 10 items of 134 documents
Large birds travel farther in homogeneous environments
2019
Aim: Animal movement is an important determinant of individual survival, population dynamics and ecosystem structure and function. Nonetheless, it is still unclear how local movements are related to resource availability and the spatial arrangement of resources. Using resident bird species and migratory bird species outside the migratory period, we examined how the distribution of resources affects the movement patterns of both large terrestrial birds (e.g., raptors, bustards and hornbills) and waterbirds (e.g., cranes, storks, ducks, geese and flamingos). Location: Global. Time period: 2003–2015. Major taxa studied: Birds. Methods: We compiled GPS tracking data for 386 individuals across 3…
Morphology, performance and attachment function in Corynosoma spp. (Acanthocephala)
2018
Background: Functional inference on the attachment of acanthocephalans has generally been drawn directly from morphology. However, performance of structures is often non-intuitive and context-dependent, thus performance analysis should be included whenever possible to improve functional interpretation. In acanthocephalans, performance analysis of attachment is available only for Acanthocephalus ranae, a species that solely relies on the proboscis to attach. Here we compare body morphology and muscle arrangement in 13 species of Corynosoma, which use their spiny body as a fundamental holdfast. A basic performance analysis using live cystacanths of two representative species is also provided.…
Revisión de las familias Capitellidae Grube, 1862 y Maldanidae Malmgren, 1867 (Annelida, Polychaeta) en el ámbito Íbero-Balear. Estudio morfológico, …
2015
Se ha realizado un estudio exhaustivo de todos los táxones pertenecientes a las familias Capitellidae y Maldanidae (Annelida, Polychaeta) en el ámbito Íbero-balear. Para ello, se han actualizado sus registros en este sector geográfico y se examinaron varias colecciones biológicas. Las colecciones estudiadas fueron la Colección de Referencia del Laboratorio de Biología Marina de la Universitat de València, la colección de Maldanidae del Muséum National d’Histoire Naturelle de Paris (MNHN) y las colecciones de Capitellidae y Maldanidae del Museo Nacional de Ciencias Naturales de Madrid (MNCN). Este estudio ha permitido la actualización del catálogo faunístico de las familias Capitellidae y Ma…
Estudio de los factores que regulan el tamaño del cerebro y la neurogénesis adulta en un reptil, la lagartija parda (Podarcis liolepis)
2015
Estudios llevados a cabo principalmente en aves y mamíferos muestran que la neurogénesis adulta responde a la regulación de numerosos factores. En los reptiles, sin embargo, la información disponible es escasa. El objetivo principal de esta tesis consiste en identificar factores que regulan el tamaño del cerebro y la neurogénesis adulta en un reptil, la lagartija parda (Podarcis liolepis). En particular estudiamos cómo el sexo, la estacionalidad y las hormonas esteroides afectan al tamaño del cerebro y de los bulbos olfativos, y a la proliferación celular y la migración de las nuevas células en el telencéfalo de estos lagartos. Para ello, capturamos 10 machos adultos de cada sexo cada dos m…
Redescription of allencotyla mcintoshi price, 1962 (monogenea), with an emended diagnosis of allencotyla price, 1962
2003
The original description of the type species of Allencotyla, A. mcintoshi Price, 1962, was based on 5 specimens collected from 1 amberjack Seriola lalandi in Florida. In this study, A. mcintoshi is redescribed based on new specimens collected from juvenile greater amberjacks S. dumerili captured off the Spanish Mediterranean coast and maintained in experimental culture tanks. Except for a slightly smaller size, individuals of S. dumerili were morphologically similar to the type specimens. However, reexamination of the type material and examination of the new specimens revealed the following discrepancies with respect to the original description: (1) the vaginal pore is unarmed and covered w…
Are epizoites biological indicators of a western Mediterranean striped dolphin die-off?
1994
During a die-off of Mediterranean striped dolphins Stenella coeruleoalba in 1990-91, 82 individuals stranded on the Spanish coast were examined for crustacean ectoparasites and epizoites. Six species were detected: Syncyarnus aequus, PenneUa sp., Xenobalanus globicipitis, Conchoderma virgatum, Lepas pectinata and Lepas cf. hillii. The barnacles L. pectinata and L. cf. hillii are reported here for the first time on cetaceans; they were attached to the teeth. C. virgaturn was also found on the teeth; this is an unusual attachment on cetaceans. X. globicipitis showed a higher prevalence on the dolphins studied than on those stranded in the same months before (1980 to 1990) and after (1991 to 1…
The helminth community of Apodemus sylvaticus (Rodentia, Muridae) in the Sierra de Gredos (Spain)
2004
The Spanish mountain range of Gredos was included in the studies conducted on the Iberian peninsula to investigate helminth fauna of small mammals. The helminth community of the wood mouse, Apodemus sylvaticus (Rodentia, Muridae), was analysed. Qualitatively, 13 helminth species were detected: Plagiorchis sp. I and Plagiorchis sp. II (Trematoda); Taenia parva larvae, T. martis larvae, T. taeniaeformis larvae, Rodentolepis straminea and R. fraterna (Cestoda); and Trichuris muris, Heligmosomoides polygyrus, Syphacia stroma, S. frederici, Aspiculuris tetraptera and Rictularia proni (Nematoda). Quantitatively, the highest prevalence (65.0%) and the mean abundance (36.9%) of H. polygyrus stand o…
Biology and conservation of marine turtle nesting in the Dominican Republic
2014
The loss of biodiversity has become one of the most pressing issues, which has lead to a growing global concern about the status of the biological resources on which human life depends. In recent decades there has been a decrease in individual populations of many species. In the Caribbean, marine turtle’s nesting rookeries have been reduced considerably, mainly due to human exploitation. A number of rookeries in this region have been studied for several decades and their status is well documented; however, many other Caribbean rookeries remain poorly described. The Dominican Republic (DR) is an area where information on marine turtle nesting activity is scarce and outdated. Surveys in the 1…
Descripción de un nuevo limácido de Menorca (Islas Baleares): Gigantomilax (Vitrinoides) benjaminus sp. n. (Gastropoda, Pulmonata)
2008
We describe a new endemic limacid slug, Gigantomilax (Vitrinoides) benjaminus n. sp. and we compare it with the nearest species, particularly with Gigantomilax (V.) majoricensis, another Balearic endemism. Characteristic features of this new species include its small size, translucid and smooth body, and totally grey dorsum with no bands or spots. The reproductive system shows a well developed vas deferens surrounded by the distal part of prostatic gland, a thin penial retractor muscle, swollen prostate and small distal genitalia. The recent redescription of Limax majoricensis by Wiktor et al. (2007) is discussed and we consider that these authors refer to G. benjaminus n. sp., and so we de…
Estrategias de migración del género Acrocephalus en la Península Ibérica
2014
El objetivo de esta tesis es profundizar en el conocimiento de las estrategias migratorias de las aves del género Acrocephalus, el carricero común A. scirpaceus y el carricerín común A. shoenobaenus, durante la migración de otoño en la Península Ibérica. Su estudio se aborda a dos niveles: por un lado, la organización espacial de la migración a nivel peninsular y por otro el comportamiento en las áreas de descanso. A nivel peninsular, se observa que los carriceros que pasaron por la zona oeste peninsular presentaron alas más cortas que los carriceros capturados en el centro y este peninsular, sugiriendo que las aves que migran a través de la ruta oeste migran distancias más cortas, lo que e…