Time filter

Source Type

Arca E.,Environmental Education Center Cascata Delle Marmore | Battisti C.,Environmental Service Protected Areas Regional Parks | Fraticelli F.,Fondazione Bioparco di Rome
Vie et Milieu | Year: 2012

We carried out a study on breeding bird communities occurring in an archipelago of 32 holm oak fragments in an urbanized landscape (Rome, central Italy). The log-transformed species-area relationship is comparable with other "insular" situations obtained from analogous mainland fragmented landscapes. We observed a quick decrease of species number when area size is lower than 2 hectares, with a significant threshold at 1 ha, unlike rural areas in which a quick species decrement occurs on a higher area size range (< 10 hectares). Species appear differently sensitive to area size of the fragments with significant responses in Dendrocopos major, Aegithalos caudatus, Sitta europaea, Parus major, Certhia brachydactyla and Fringilla coelebs. Considering the recreational role of the biodiversity for human populations inhabiting large metropolitan areas, the threshold in size (about 1 ha in fragment area) evidenced in this study may be useful for urban park management strategies. Source

During the last decade, rose-ringed parakeet's population of Villa Borghese (an urban park in Rome - Italy) increased dramatically until it reached it's maximum in 2010, then stabilising after a light decrease. From 1999 to 2013 population increased of 70.5% each year, on average. From collected data local population of Piciformes do not seem to be affected. A clear preference for arboreal and shrubby layer of the vegetation was observed when feeding on a variety of non-native species, this confirming the strong relationship of the taxon with anthropic habitats. © 2014 CISO - Centro Italiano Studi Ornitologici. Source

Vignoli L.,Third University of Rome | Macale D.,Fondazione Bioparco di Rome | Luiselli L.,Rivers State University of Science And Technology | Lecis R.,University of Sassari | Casula P.,Ente Foreste della Sardegna
ORYX | Year: 2016

Assessing and updating the extinction risk and conservation status of species and populations is paramount to guide management strategies. Maintaining up-to-date and realistic geographical distribution maps of individual species is one aspect of this. We report an updated distribution for an Italian island endemic amphibian, the Sardinian newt Euproctus platycephalus, categorized as Endangered on the IUCN global and national Red Lists. The distribution of E. platycephalus was reassessed by means of visual surveys, questionnaires, interviews and scientific literature. The species was found over a geographical range comparable to that used for the IUCN assessment but we recorded a significantly larger number of populations (57 vs 14). There was no appreciable difference in the species’ Extent of Occurrence between 1972–1974 and 2010–2015. Area of Occupancy increased between past (1972–1974 and 1999–2000) and present (2010–2015) distribution records. Based on this updated distribution and considering that several new populations have been found, the distribution of the species may still be underestimated. Given the novel distribution data provided here and the need for new long-term demographic data, we recommend that the conservation status of E. platycephalus be reassessed. In the Italian national Red List a potential overstatement of extinction risk is evident for other amphibian species, possibly because the information used in their assessment is deficient. Considering that monitoring rare and elusive species is costly and time consuming we recommend more extensive use of multiple sources of information for Red List assessments. Copyright © Fauna & Flora International 2016 Source

Rovelli V.,Third University of Rome | Randi E.,European Commission - Joint Research Center Ispra | Randi E.,University of Aalborg | Davoli F.,European Commission - Joint Research Center Ispra | And 3 more authors.
Biological Journal of the Linnean Society | Year: 2015

Polyandry is a widespread mating strategy, found in a broad number of taxa. Among amphibians, polyandry, and multiple paternity as its direct consequence, is quite common in salamanders, especially within Ambystomatidae and Plethodontidae. In the suborder Salamadroidea the existence of two different types of spermatheca allows several kinds of polyandry strategies to appear. We used multilocus microsatellite genotyping to investigate the presence of polyandry and its effects on the paternity in a previously unstudied species with a terrestrial habit, Salamandrina perspicillata. We collected gravid females in their natural habitat and analysed the paternity of the offspring by using the software COLONY and GERUD. We found that all the analysed clutches had been fertilized by 2-4 males and that in every clutch one male had sired most of the offspring. Our results confirmed that polyandry is an important component of the mating system of this species, suggesting that females are able to recognize the sperm of the male that will provide a genetic benefit for their offspring. We found evidence of female cryptic choice based on males' genetic dissimilarity: (1) males who sire most of the offspring of a given female tend to be genetically different from their sexual partner; (2) a same male, when mated with two females, sired a proportion of the offspring inversely correlated with his genetic similarity to the female; (3) genetic dissimilarity between mating partners is positively correlated with offspring heterozygosity. According to the genetic compatibility model, we hypothesized that in the observed non resource-based mating system the indirect benefit for the offspring should reflect interactions between paternal and maternal genomes rather than the inheritance of the so-called 'good genes'. This study suggests a polygynandrous mating system for the study species and provides the first report in a salamandrid species in natural condition that reproductive success of males is correlated with genetic dissimilarity between mates. Moreover, we found evidence of an offspring benefit (higher heterozygosity) derived from the most genetically dissimilar father. © 2015 The Linnean Society of London. Source

Predazzi I.M.,Vanderbilt University | Rokas A.,Vanderbilt University | Deinard A.,University of Minnesota | Schnetz-Boutaud N.,Vanderbilt University | And 11 more authors.
Circulation: Cardiovascular Genetics | Year: 2013

Background-Natural selection shapes many human genes, including some related to complex diseases. Understanding how selection affects genes, especially pleiotropic ones, may be important in evaluating disease associations and the role played by environmental variation. This may be of particular interest for genes with antagonistic roles that cause divergent patterns of selection. The lectin-like low-density lipoprotein 1 receptor, encoded by OLR1, is exemplary. It has antagonistic functions in the cardiovascular and immune systems because the same protein domain binds oxidized lowdensity lipoprotein and bacterial cell wall proteins, the former contributing to atherosclerosis and the latter presumably protecting from infection. We studied patterns of selection in this gene, in humans and nonhuman primates, to determine whether variable selection can lead to conflicting results in cardiovascular disease association studies. Methods and Results-We analyzed sequences from 11 nonhuman primate species, as well as single-nucleotide polymorphisms and sequence data from multiple human populations. Results indicate that the derived allele is favored across primate lineages (probably because of recent positive selection). However, both the derived and ancestral alleles were maintained in human populations, especially European ones (possibly because of balancing selection derived from dual roles of LOX-1). Balancing selection likely reflects response to diverse environmental pressures among humans. Conclusions-These data indicate that differential selection patterns, within and between species, in OLR1 render association studies difficult to replicate even if the gene is etiologically connected to cardiovascular disease. Selection analyses can identify genes exhibiting gene-environment interactions critical for unraveling disease association. © 2013 American Heart Association, Inc. Source

Discover hidden collaborations