Search results for "classification"

Bayesian analysis improves experimental studies about temporal patterning of aggression in fish.

2017

Made available in DSpace on 2018-12-11T17:15:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-12-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) This study aims to describe a Bayesian Hierarchical Linear Model (HLM) approach for longitudinal designs in fish's experimental aggressive behavior studies as an alternative to classical methods In particular, we discuss the advantages of Bayesian analysis in dealing with combined variables, non-statistically significant results and required sample size using an experiment of angelfish (Pterophyllum scalare) species as case study. Groups of 3 individuals were subjected to daily observations recorded for 10 min durin…

Conflicts between touristic recreational activities and breeding shearwaters: short-term effect of artificial light and sound on chick weight

2018

Human disturbances are increasingly becoming a conservation concern for many populations of colonial seabirds. Colonially reproducing species are particularly vulnerable to localised disturbances because detrimental elements can simultaneously affect the entire population. Studies of petrels and shearwaters have shown that light pollution, in particular, can be harmful for both fledglings and adults, but little is known of the way such anthropogenic elements affect the quality of parental care at the nest. Chick provisioning in petrels and shearwaters occurs exclusively at night and is also negatively correlated with the amount of moonlight. We tested the hypothesis that high-intensity ligh…

Reappraisal of ‘chronospecies' and the use of Arvicola (Rodentia, Mammalia) for biochronology.

2008

13 pages; International audience; The water vole, genus Arvicola, is characterised by a broad geographic distribution throughout Europe and is widespread during the late Middle and Upper Pleistocene. This genus is used as a major biostratigraphic tool within the Quaternary. Specific determinations using the Schmelzband-Differenzierung-Quotient or SDQ have identified many chronospecies within the fossil species Arvicola cantiana (Hinton, 1910). As SDQ calculation remains limited, this study reappraises the Arvicola genus in terms of morphodiversity and morphospace using outline analysis which takes into account the tooth as a whole. Outline analysis suggests that one single species of Arvico…

Mandible morphology, dental microwear, and diet of the extinct giant rats Canariomys (Rodentia: Murinae) of the Canary Islands (Spain)

2010

An ecomorphological approach of mandible shape through Fourier analyses combined with a paleodietary analysis of dental microwear patterns is used to reconstruct the diet of the extinct endemic Canariomys bravoi Crusafont, Pairo & Petter, 1964 and Canariomys tamarani Lopez-Martinez & Lopez-Jurado, 1987. These two large rodents, respectively, lived on Tenerife and Gran Canaria, the central islands of the Canarian Archipelago. Mandible shape and dental microwear respectively inform us on the volume of vegetal matter and on the presence of grass in the diet. Both Canariomys, which are of similar size, possess relatively similar mandible outlines and microwear patterns. For each species, a diet…

Bioluminescent-like squamation in the galeomorph shark Apristurus ampliceps (Chondrichthyes: Elasmobranchii)

2018

Galeomorph sharks constitute the most taxonomically and ecologically diverse superorder of living selachians. Despite comprising several typically deep-water taxa, no bioluminescent species have been reported in this group so far. Interestingly, the study of shark squamation has been revealed in recent years to be a good proxy for inferring some ecological aspects of poorly known species. In particular, the high morphological specificity of the dermal denticles and the squamation patterns of all currently-known bioluminescent sharks could constitute a potential tool for predicting bioluminescence in both fossil and living taxa. Following this idea, we provide the first evidence supporting t…

Changes in spawning-stock structure and recruitment pattern of red mullet, Mullus barbatus, after a trawl ban in the Gulf of Castellammare (central M…

2008

Abstract Fiorentino, F., Badalamenti, F., D’Anna, G., Garofalo, G., Gianguzza, P., Gristina, M., Pipitone, C., Rizzo, P., and Fortibuoni, T. 2008. Changes in spawning-stock structure and recruitment pattern of red mullet, Mullus barbatus, after a trawl ban in the Gulf of Castellammare (central Mediterranean Sea). – ICES Journal of Marine Science, 65: 1175–1183. The increase in biomass of red mullet, Mullus barbatus, in the Gulf of Castellammare (northwestern Sicily, central Mediterranean) after a 14-year trawl ban, prompted us to compare the spawning-stock structure and the recruitment pattern before and after the closure. Datasets obtained from three experimental trawl surveys were availab…

Microsatellite analysis of red mullet Mullus barbatus (Perciformes, Mullidae) reveals the isolation of the Adriatic Basin in the Mediterranean Sea

2009

AbstractMaggio, T., Lo Brutto, S., Garoia, F., Tinti, F., and Arculeo, M. 2009. Microsatellite analysis of red mullet Mullus barbatus (Perciformes, Mullidae) reveals the isolation of the Adriatic Basin in the Mediterranean Sea. – ICES Journal of Marine Science, 66: 1883–1891. The red mullet Mullus barbatus is commercially one of the most important demersal fish resources in the Mediterranean. Molecular data on its genetic population structure throughout the Mediterranean are reported. Six microsatellite loci displayed a high degree of expected heterozygosity and a high allele number per locus. The Hardy–Weinberg equilibrium test revealed an overall tendency towards heterozygote deficiency, …

The effectiveness of fish feeding behaviour in mirroring trawling-induced patterns

2017

The ability to observe and predict trawling-induced patterns at spatial and temporal scales that are relevant to inform realistic management strategies is a challenge which scientists have consistently faced in recent decades. Here, we use fish feeding behaviour, a biological trait easily impaired by trawling disturbance, to depict alterations in fish condition (i.e. individual fitness) and feeding opportunities. The benthivorous fish Mullus barbatus barbatus was selected as a model species. The observed trends of responses to trawling in prey species confirmed the effectiveness of a non-trawled zone in sustaining higher levels of diet diversity (e.g. quantity and quality of ingested prey) …

2017

AbstractBeneficial effects of CO2 on photosynthetic organisms will be a key driver of ecosystem change under ocean acidification. Predicting the responses of macroalgal species to ocean acidification is complex, but we demonstrate that the response of assemblages to elevated CO2 are correlated with inorganic carbon physiology. We assessed abundance patterns and a proxy for CO2:HCO3− use (δ13C values) of macroalgae along a gradient of CO2 at a volcanic seep, and examined how shifts in species abundance at other Mediterranean seeps are related to macroalgal inorganic carbon physiology. Five macroalgal species capable of using both HCO3− and CO2 had greater CO2 use as concentrations increased.…

Light Conditions Affect NaCl-Induced Physiological Responses in a Clonal Plant Species Hydrocotyle vulgaris

2020

Abstract In order to understand if differences in light conditions can affect responses of a clonal plant species to increased soil salinity, the long-term effect of two substrate concentrations of NaCl on leaf growth, clonal plasticity and oxidative enzyme (peroxidase and polyphenol oxidase) activity in Hydrocotyle vulgaris L. plants grown at low, moderate and high light conditions was studied. H. vulgaris appeared to be a shade-tolerant species, since both leaf blade and petiole growth was inhibited at low light intensity. At low light intensity, H. vulgaris plants represented characteristics of halophytes with significant stimulation of leaf blade and petiole growth by NaCl, especially a…