166 research outputs found

    A potential record of a procolophonid parareptile from the Triassic of the Iberian Peninsula

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    Cranial and postcranial remains from the Middle Triassic of the Northeastern part of the Iberian Peninsula are reported and tentatively assigned to Procolophonidae. The finding is the first occurrence of a procolophonid parareptile in the Iberian Peninsula, representing the southernmost record of the group in Europe. The fossilbearing locality is dated as Anisian (Middle Triassic) and includes three tooth-bearing bones, two cranial bone fragments and one interclavicle. The mandible described herein includes nine teeth. No cusps or complete crowns are preserved, but sections of the teeth are available. The three anterior teeth progressively decrease in size from front to back, whereas the teeth from the fourth to the eighth position present the opposite trend. The last tooth (the ninth) is clearly reduced in comparison to the previous ones. A close relationship with Anomoiodon-Kapes is suggested, however, more material is required in order to assess the exact taxonomical determination of the Iberian remains. This finding is expected to shed some light on the geographical distribution of procolophonines

    Oxidation in fresh and S1'ray-dried û)3 and to6 fatty acid enriched eggs vitamin E and cantiiaxantin

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    A trial with 192 laying hens was conducted to study the effect of Vitamin E and Canthaxanthin as antioxidants in w3 either w6 fatty acid (FA) enriched eggs. The animals were randomlyassigned to eight treatments resulted from the supplementation of a basal dietcontaining5% of linseed oil (L) orsunfloweroil (S) with 200 ppm ofutocopheryl acetate (LE and SE), 5ppm of Canthaxathin(LC and SC) or both (LEG and SEC). After 40 days of experimental treatment, eggs were collected and oxidation was measured by the TBA methodology (Botsoglou et al., 1994) on fresh and spray-dried eggs. On fresh eggs there were no differences in TBArs values (expressed as ng MDA/g for any of the studied factors. On spray-dried eggs, the values obtained were ó to X-fold higher than in fresh eggs. Eggs from the diets with linseed oil (26,6 % I'UFA and 10,4 % m3) showed higher values than those from diets with sunflower oil (28,0 % PUFA and 26,7 % w6) (L: 338,7 v.v. S: 248,6; P0,05). It can be concluded that w3 FA enriched eggs are more susceptible to oxidation than u6 FA enriched eggs. Supplementation with 200 ppm of Vitamin E can reduce the oxidation induced by the spray-drying process, but supplementation with 5 ppm of Canthaxanthin had no significant effect as antioxidant

    Nuevos enfoques sobre los vertebrados del Pérmico y Triásico de la Península Ibérica, con énfasis en las cuencas Pirenaica y Catalana

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    Few studies paid attention to the Permian and Triassic vertebrates from the Iberian Peninsula and a re-evaluation of these faunas is needed in order to compare them with other European basins. As a first step, we present here the available data from the Catalonian and Pyrenean basins (NE of the Iberian Peninsula), offering new insights on the diversity and temporal distribution of their vertebrate faunas. The two basins have yielded unexpectedly abundant and diverse vertebrate assemblages, including fishes, amphibians and reptiles from continental and marine environments. The revision of classical finds and the analysis of new material provide data towards an understanding of the evolutionary and palaebiogeographical history of the Permian and Triassic vertebrate Iberian faunas. Permian remains mainly correspond to footprints recovered from alluvial deposits; the osteological record is scarce in the Iberian Peninsula. Early Triassic vertebrate localities are unknown. Middle Triassic faunas are abundant and reflect the change from continental environments to a wide diversity of coastal and marine depositional environments. During the Anisian, faunas are represented by footprints and skeletal remains of amphibians (capitosaurs) and terrestrial reptiles (archosauromorphs and procolophonoids). Ichthyofauna, sauropterygians, thalattosaurs and protorosaurians are known through the late Anisian and Ladinian. Finally, Late Triassic localities representing coastal environments have also yielded marine reptiles (sauropterygians) and a diverse ichthyofauna.Se han realizado hasta el momento pocos estudios de los vertebrados del Pérmico y el Triásico de la Península Ibérica y por este motivo, una re-evaluación de estas faunas es necesaria para compararlas con las halladas en otras cuencas europeas. Como primer paso, aquí presentamos la información disponible de las cuencas Catalana y Pirenaica (NE de la Península Ibérica), ofreciendo nuevos puntos de vista sobre la diversidad y distribución temporal de las faunas de vertebrados. Las dos cuencas muestran una inesperada abundancia y diversidad de faunas de vertebrados, incluyendo peces, anfibios y reptiles de ambientes continentales y marinos. La revisión de hallazgos clásicos y el análisis de nuevo material proporcionan nuevos datos para la comprensión de la historia evolutiva y paleobiogeográfica de las faunas de vertebrados durante el Pérmico y el Triásico en la Península Ibérica. Los hallazgos en el Pérmico corresponden mayoritariamente a pisadas encontradas en depósitos aluviales, siendo el registro osteológico muy escaso en la Península Ibérica. Se desconocen localidades de vertebrados del Triásico inferior. Las faunas del Triásico medio son abundantes y reflejan el cambio desde ambientes continentales hasta una amplia diversidad de ambientes deposicionales costeros y marinos. Durante el Anisiense, las faunas están representadas por pisadas y restos esqueléticos de anfibios (capitosaurios) y reptiles terrestres (arcosauriformes y procolofonoideos). De finales del Anisiense y el Ladiniense se conoce ictiofauna, sauropterigios, talattosaurios y protorosaurios. Finalmente, las localidades del Triásico superior están representadas por ambientes costeros conservando reptiles marinos (sauropterigios) y una diversa ictiofauna

    A fast-growing basal troodontid (Dinosauria: Theropoda) from the latest Cretaceous of Europe

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    Altres ajuts: "Xarxes paleocològiques dels jaciments de dinosaures del Cretaci català" ("Paleoecological networks of the dinosaur quarries of the Catalan Cretaceous") CLT/903/2018/67, funded by the Departament de Cultura of the Generalitat de Catalunya.A characteristic fauna of dinosaurs and other vertebrates inhabited the end-Cretaceous European archipelago, some of which were dwarves or had other unusual features likely related to their insular habitats. Little is known, however, about the contemporary theropod dinosaurs, as they are represented mostly by teeth or other fragmentary fossils. A new isolated theropod metatarsal II, from the latest Maastrichtian of Spain (within 200,000 years of the mass extinction) may represent a jinfengopterygine troodontid, the first reported from Europe. Comparisons with other theropods and phylogenetic analyses reveal an autapomorphic foramen that distinguishes it from all other troodontids, supporting its identification as a new genus and species, Tamarro insperatus. Bone histology shows that it was an actively growing subadult when it died but may have had a growth pattern in which it grew rapidly in early ontogeny and attained a subadult size quickly. We hypothesize that it could have migrated from Asia to reach the Ibero-Armorican island no later than Cenomanian or during the Maastrichtian dispersal events

    Vitamin E levels and lipid oxidation in ω3 fatty acids enriched eggs

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    With the aim to establish the required amount of α-tocopherol to effectively prevent lipid oxidation in w3 FA enriched eggs, a trial was conducted with 2XX laying hens. Birds were randomly assigned to four treatments resulted from supplying a basal diet containing 5% of linseed oil (diet: 65% PUFA, 34,5% m3) with 0 (C), 50 (50E), 100 (I00E) or 200 (200E) ppm of alpha-tocopherol acetate. After 25 days of feeding, eggs were collected and lipid oxidation was measured by the Induced TBArs methodologya (Kornbrust and Mavis, 19X0) and expressed as ng MDA/g egg. At 150 min of incubation, supplementation with 50, 100, or 200 ppm of Vitamin F. promoted a dramatic decrease in the TBArs values of all treatments when compared to the control group (C: 2,63 v.v. 50E: 0,47; I00E: 0,4X; 200E: 0,3X; P«).00l). Moreover, no significant differences were found according to different levels of Vitamin E supplementation. From these data, we can conclude that supplying hens' diets with 50 ppm of alphatocopherol acetate can effectively reduce the lipid oxidation in co3 FA enriched eggs

    El rol dels terpens en la competència entre plantes invasores i natives a Hawaii

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    Els terpens, hidrocarburs derivats de l'isoprè, són emesos i emmagatzemats per moltes plantes. La seva funció biològica i ecològica és estudiada des de fa uns anys, havent estat proposades diverses possibles funcions, com per exemple la protecció davant dels herbívors o com a mecanisme antiestrès metabòlic. Investigacions realitzades per científics del CREAF a les illes Hawaii han permès detectar diferències en l'acumulació foliar de terpens entre les espècies nadiues i invasives a través de l'screening efectuat en una àmplia mostra de les principals espècies forestals natives i invasives a l'illa d'Oahu. Aquests resultats aporten noves pistes per conèixer els mecanismes que expliquen l'èxit competitiu que permet que moltes espècies introduïdes en un nou hàbitat esdevinguin un problema ecològic per la seva expansió i exclusió competitiva d'espècies nadiues.Los terpenos, hidrocarburos derivados del isopreno, son emitidos y almacenados por muchas plantas. Su función biológica y ecológica está siendo estudiada desde hace unos años, habiendo sido propuestas varias posibles funciones, como por ejemplo la protección frente a los herbívoros o como mecanismo antiestrés metabólico. Investigaciones realizadas por científicos del CREAF en las islas Hawai han permitido detectar diferencias en la acumulación foliar de terpenos entre las especies nativas e invasivas a través del screening efectuado en una amplia muestra de las principales especies forestales nativas y invasivas en la Isla de Oahu. Estos resultados aportan nuevas pistas para conocer los mecanismos que explican el éxito competitivo que permite que muchas especies introducidas en un nuevo hábitat se conviertan en un problema ecológico por su expansión y exclusión competitiva de especies nativas

    Stoichiometry patterns of plant organ N and P in coastal herbaceous wetlands along the East China Sea : implications for biogeochemical niche

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    Background and aims: Nitrogen (N) and phosphorus (P) are essential nutrients for plant growth, and their availability and stoichiometry play pivotal roles in trophic dynamics and community composition. The biogeochemical niche (BN) hypothesis claims that each species should have an optimal elemental composition and stoichiometry as a consequence of its optimal function in its specific ecological niche. Little attention, however, has been given to N and P stoichiometric patterns and test the BN hypothesis in coastal wetland communities from the perspective of organ and species-specific comparisons.Methods: We investigated factors responsible for changes in N and P stoichiometry patterns in different functional groups in coastal wetlands and tested the BN hypothesis by evaluating N and P composition in whole aboveground plants and organs.Results: Both plant N and P concentrations were high in coastal wetlands, indicating that N and P were not likely limiting, although the N:P ratio was slightly lower than the ratio reported in global and Chinese terrestrial flora. N and P concentrations and N:P ratios varied strongly between C₃ and C₄ species, among species, and among organs within species. N and P concentrations were not correlated with latitude, mean annual temperature and precipitation, although N:P ratio was weakly correlated with these factors. The differences in N and P concentrations and N:P ratios along the wetland gradients were mainly because of the species-specific community composition of each site.Conclusions: The results are consistent with the BN hypothesis. First, N and P composition is species-specific (homeostatic component of BN), each species tends to maintain its own composition even growing in different sites with different species composition. Second, different species, despite maintaining their own composition, have distinct degree of composition phenotypic flexibility (flexibility component of BN); this different size of "biogeochemical space" was observed when comparing different species living in the same community and the shifts in species BN space and size was observed when comparing populations of the same species living in different sites

    A Roadmap for the Restoration of Mediterranean Macroalgal Forests

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    Canopy-forming macroalgae play a crucial role in coastal primary production and nutrient cycling, providing food, shelter, nurseries, and habitat for many vertebrate and invertebrate species. However, macroalgal forests are in decline in various places and natural recovery is almost impossible when populations become locally extinct. Hence, active restoration emerges as the most promising strategy to rebuild disappeared forests. In this regard, significant efforts have been made by several EU institutions to research new restoration tools for shallow and mesophotic reef habitats (e.g., MERCES EU project, AFRIMED, and ROCPOP-life) and effective techniques have subsequently been proposed to promote self-sustaining populations. Recent research indicates that macroalgal forest recovery requires a broad spectrum of measures, ranging from mitigating human impacts to restoring the most degraded populations and habitats, and that the viability of large restoration actions is compromised by ongoing human pressures (e.g., pollution, overgrazing, and climate change). We propose a roadmap for Mediterranean macroalgal restoration to assist researchers and stakeholders in decision-making, considering the most effective methods in terms of cost and cost-effectiveness, and taking background environmental conditions and potential threats into account. Last, the challenges currently faced by the restoration of rocky coastal ecosystems under changing climate conditions are also discussed

    Phosphorus accumulates faster than nitrogen globally in freshwater ecosystems under anthropogenic impacts

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    Combined effects of cumulative nutrient inputs and biogeochemical processes that occur in freshwater under anthropogenic eutrophication could lead to myriad shifts in nitrogen (N):phosphorus (P) stoichiometry in global freshwater ecosystems, but this is not yet well-assessed. Here we evaluated the characteristics of N and P stoichiometries in bodies of freshwater and their herbaceous macrophytes across human-impact levels, regions and periods. Freshwater and its macrophytes had higher N and P concentrations and lower N : P ratios in heavily than lightly human-impacted environments, further evidenced by spatiotemporal comparisons across eutrophication gradients. N and P concentrations in freshwater ecosystems were positively correlated and N : P was negatively correlated with population density in China. These results indicate a faster accumulation of P than N in human-impacted freshwater ecosystems, which could have large effects on the trophic webs and biogeochemical cycles of estuaries and coastal areas by freshwater loadings, and reinforce the importance of rehabilitating these ecosystems
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