Search results for "ECOLOGIA"
showing 10 items of 1399 documents
Las concepciones de los profesores de ciencias mexicanos sobre la situación y futuro del mundo: una llamada de atención
2018
<span>Durante la Conferencia de las Naciones Unidas sobre Desarrollo y Medio Ambiente, celebrada en Río en 1992, se reclamó una decidida acción de los educadores de todas las áreas para que los ciudadanos y ciudadanas adquieran una correcta percepción de la situación de crisis planetaria y sus posibles soluciones y puedan participar en la toma fundamentada de decisiones. Nuestro propósito en este trabajo es realizar un primer estudio de cuáles son las concepciones de los profesores mexicanos a este respecto, porque sin una correcta percepción de los problemas que afectan a la sostenibilidad la vida humana no podemos esperar una implicación efectiva en esta dimensión de la educación.&l…
Quantitative genetic analysis of floral traits shows current limits but potential evolution in the wild
2023
The vast variation in floral traits across angiosperms is often interpreted as the result of adaptation to pollinators. However, studies in wild populations often find no evidence of pollinator-mediated selection on flowers. Evolutionary theory predicts this could be the outcome of periods of stasis under stable conditions, followed by shorter periods of pollinator change that provide selection for innovative phenotypes. We asked if periods of stasis are caused by stabilizing selection, absence of other forms of selection or by low trait ability to respond even if selection is present. We studied a plant predominantly pollinated by one bee species across its range. We measured heritability …
Geosphere-biosphere interactions in bio-activity volcanic lakes: Evidences from Hule and Rìo Cuarto (Costa Rica)
2014
Hule and R ́ıo Cuarto are maar lakes located 11 and 18 km N of Poa ́s volcano along a 27 km long fracture zone, in the Central Volcanic Range of Costa Rica. Both lakes are characterized by a stable thermic and chemical stratification and recently they were affected by fish killing events likely related to the uprising of deep anoxic waters to the surface caused by rollover phenomena. The vertical profiles of temperature, pH, redox potential, chemical and isotopic compositions of water and dissolved gases, as well as prokaryotic diversity estimated by DNA fingerprinting and massive 16S rRNA pyrosequencing along the water column of the two lakes, have highlighted that different bio-geochemica…
Haplotype analyses reveal novel insights into tomato history and domestication driven by long-distance migrations and latitudinal adaptations.
2022
Abstract A novel haplotype-based approach that uses Procrustes analysis and automatic classification was used to provide further insights into tomato history and domestication. Agrarian societies domesticated species of interest by introducing complex genetic modifications. For tomatoes, two species, one of which had two botanical varieties, are thought to be involved in its domestication: the fully wild Solanum pimpinellifolium (SP), the wild and semi-domesticated Solanum lycopersicum var. cerasiforme (SLC) and the cultivated S. l. var. lycopersicum (SLL). The Procrustes approach showed that SP evolved into SLC during a gradual migration from the Peruvian deserts to the Mexican rainforests…
Giant uterus in a patient with Klippel-Trenaunay syndrome. Report of a case
2022
Introduction: Klippel-Trenaunay syndrome is an uncommon congenital disease also called angio-osteodystrophy syndrome for its typical disorders characterized by abnormal growth of the soft tissues and bones and vascular malformations. Case report: In this report, we present a rare case of a 46-year-old nulliparous woman with Klippel-Trenaunay syndrome. She suffered from an abnormal uterine bleeding accompanied by severe anemia with need for multiple blood transfusions. At the time of admission, physical examination revealed port-wine stains and varicose veins on her lower limbs and hypertrophy of left lower extremity. We carried out an open bilateral hysteroannexectomy. Histopathology examin…
The geochemical riddle of “low-salinity gypsum” deposits
2022
International audience; Gypsum makes up about one fifth of giant salt deposits formed by evaporation of seawater throughout Earth’s history. Although thermodynamic calculations and precipitation experiments predict that gypsum precipitates when the salinity of evaporating seawater attains about 110 g kg-1, gypsum deposits of the Mediterranean Salt Giant often bear the geochemical signature of precipitation from less saline water masses. Addressing this geochemical riddle is important because marine gypsum deposition and continental gypsum erosion affect the global carbon cycle. We investigated gypsum deposits formed in the marginal basins of the Mediterranean Sea during the Messinian Salini…
The rodents of the Pirro Nord fauna (Foggia, Southern Italy)
2013
The rodent fauna of various fissure fillings of the Pirro Nord karstic complex are examined here. They have been collected during several field caingns starting from the 70’s until 2006 and are here examined in a comprehensive matter. Hundreds of specimens of arvicolids, murids and, in much lower amount, Glirids have been recovered from several of these fissures. They belong to the species Allophaiomys ex gr. ruffoi, Myodes sp. Apodemus flavicollis and Muscardinus sp.
Jellyfish Stings Trigger Gill Disorders and Increased Mortality in Farmed Sparus aurata (Linnaeus, 1758) in the Mediterranean Sea
2016
11 pages, 4 figures
Evolutionary morphology in shape and size of haptoral anchors in 14 Ligophorus spp. (Monogenea: Dactylogyridae).
2017
The search for phylogenetic signal in morphological traits using geometric morphometrics represents a powerful approach to estimate the relative weights of convergence and shared evolutionary history in shaping organismal form. We assessed phylogenetic signal in the form of ventral and dorsal haptoral anchors of 14 species of Ligophorus occurring on grey mullets (Osteichthyes: Mugilidae) from the Mediterranean, the Black Sea and the Sea of Azov. The phylogenetic relationships among these species were mapped onto the morphospaces of shape and size of dorsal and ventral anchors and two different tests were applied to establish whether the spatial positions in the morphospace were dictated by …
Concurrent environmental stressors and jellyfish stings impair caged European sea bass (Dicentrarchus labrax) physiological performances
2016
9 pages, 5 figures, 4 tables