Search results for "Mediterranean."
showing 10 items of 3129 documents
The size and shape of shells used by hermit crabs: A multivariate analysis of Clibanarius erythropus
2009
Shell attributes such as weight and shape affect the reproduction, growth, predator avoidance and behaviour of several hermit crab species. Although the importance of these attributes has been extensively investigated, it is still difficult to assess the relative role of size and shape. Multivariate techniques allow concise and efficient quantitative analysis of these multidimensional properties, and this paper aims to understand their role in determining patterns of hermit crab shell use. To this end, a multivariate approach based on a combination of size-unconstrained (shape) PCA and RDA ordination was used to model the biometrics of southern Mediterranean Clibanarius erythropus populatio…
Health effects of mercury ingested through consumption of seafood
1995
It is known world-wide literature that seafood consumption is the main source of mercury intake in people not occupationally exposed. Several studies on the presence of mercury in sea water, sediment and fish and its effects on human health have been carried out in many countries in the Mediterranean area such as Greece, Italy and Jugoslavia. Few data have been published on Sicilian coastal population, consumers of high amounts of fish and on seawater status as the starting point of alimentary chains involving marine food. This study was carried out in July 1991 and July 1992 to determine total mercury and methylmercury levels in selected populations of the coast of Sicily: fishermen in a l…
Spatial analysis of lanner falcon habitat preferences: Implications for agro-ecosystems management at landscape scale and raptor conservation
2014
Abstract Sicily hosts the largest European population of the endangered lanner falcon, a poorly known species which needs conservation planning based on habitat preferences. A distribution model on 10 × 10 km cells of Sicily was described using Generalized Linear Models and variation partitioning methods. This modelling approach extracted explanatory factors, pure and joint effects of greatest influence from subsets of variables controlled for multi-collinearity and spatial autocorrelation. Analytical cartography used the environmental favourability function to assess habitat preferences, and the insecurity index estimated the degree to which lanner falcon occupancy is represented in the Na…
Megabenthos Underwater Video (MUV): a new device to evaluate species distribution in hard-to-reach marine areas
2021
A device, called Megabenthos Underwater Video (MUV), was designed and built for the counting and the size estimate of benthic organisms in hard-to-reach areas. Since 2014 Cassiopea andromeda, an invasive alien jellyfish in the Mediterranean Sea with benthic behavior, colonized a recreational harbor (Cala) of Palermo with a stable population. Studying the species distribution in this area with classical methods (such as visual census, ROV, etc.) was not applicable due to the large presence of obstacles (ropes, anchor cables, boats) and to dive difficulties in these types of area. The MUV was tested from 2017 to 2018 for the study of the spatial-temporal distribution of C. andromeda in the Ca…
Seasonal population dynamics of Zeuxapta seriolae (Monogenea: Heteraxinidae) parasitising Seriola dumerili (Carangidae) in the Western Mediterranean.
2013
We examined the seasonal and yearly population dynamics of the monogenean pathogen Zeuxapta seriolae on juvenile fish from wild populations of Seriola dumerili. The study is based on bimonthly monitoring between April, 2005 and April, 2007 off Majorca, and newly obtained monogenean population data for juvenile fish from three additional localities in the Western Mediterranean (off Alicante, Corsica and Sardinia). We documented the highest intensities and abundances of Z. seriolae, with mean abundance values similar to or higher than those reported in the single case of wild fish mortalities reported to date. There was a recurrent pattern of seasonal change in infection with Z. seriolae in t…
Comparative analysis of biological and ecological differentiation of Anemone palmata L. (Ranunculaceae) in the western Mediterranean (France and Spai…
2002
The western Mediterranean geophyte Anemone palmata L. is one of the most endangered angiosperm taxa in France. The biological and ecological characteristics of French populations are contrasted with those of populations from near the centre of the species distribution in east Spain. A Correspondence Analysis discriminates the French and Spanish populations according to substrate and the composition of the plant communities where they grow. The karyological study reveals that east Spanish plants are autotetraploid, whilst the French are all diploid. In addition, morphological differences were registered, Spanish plants generally being more vigorous. French populations consist mostly of senil…
Taxonomy and evolution of the Convolvulus sabatius complex (Convolvulaceae)
2010
A revision of the Convolvulus sabatius complex is presented and five taxa are now recognised. Convolvulus valentinus is re-circumscribed to comprise only blue-flowered individuals. Yellow-flowered plants previously referred to this species are transferred to C. supinus where they are recognised as a distinct variety: C. supinus var. melliflorus, comb nov. Variation in intensity of flower colour, pubescence and leaf shape among blue-flowered C. valentinus is highly variable within populations and in contrast to earlier treatments, no infraspecific taxa based on these traits are recognised. Despite suggestions to the contrary, the delimitation of the cultivated ornamental C. sabatius and its …
Origination and extinction patterns of mammals in three central Western Mediterranean islands from the Late Miocene to Quaternary
2008
Abstract An overview of the population histories of three insular realms (Gargano palaeo-archipelago, Sardinia–Maritime Tuscany palaeo-bioprovince and the Sicilian insular complex) during the Late Miocene and Quaternary are here presented. The complexity of biodiversity changes in the islands is analysed to propose an interpretation of origination and extinction patterns. The study highlighted several important aspects of insular faunas. Evolutionary radiations were found to contribute significantly only to the Gargano faunal diversity, likely because the area was an archipelago at the time. Another interesting result is that large and small mammals do not disperse and become extinct all at…
Prevention of 7-Ketocholesterol-Induced Overproduction of Reactive Oxygen Species, Mitochondrial Dysfunction and Cell Death with Major Nutrients (Pol…
2020
The brain, which is a cholesterol-rich organ, can be subject to oxidative stress in a variety of pathophysiological conditions, age-related diseases and some rare pathologies. This can lead to the formation of 7-ketocholesterol (7KC), a toxic derivative of cholesterol mainly produced by auto-oxidation. So, preventing the neuronal toxicity of 7KC is an important issue to avoid brain damage. As there are numerous data in favor of the prevention of neurodegeneration by the Mediterranean diet, this study aimed to evaluate the potential of a series of polyphenols (resveratrol, RSV
A Nomenclatural and Taxonomic Revision of the Senecio squalidus Group (Asteraceae)
2022
Senecio squalidus (Asteraceae) currently includes nine subspecies distributed in North and Central Europe and in the Mediterranean basin. Within this taxonomic aggregate, many species have been described, but research on their nomenclatural types is incomplete. A complete nomenclatural survey of 19 names belonging to this taxonomically critical group was carried out. Fourteen lectotypes are here designated. The nomenclatural analysis, complemented by field investigations in the type localities of the taxa described in the Central Mediterranean, allowed us to accept 10 species. Accordingly, we proposed here a new name and a new missing combination at a specific level: S. aknoulensis and S. c…