79 research outputs found

    Territory quality and male dominance in Tropidurus torquatus (Squamata, Tropiduridae)

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    In territorial species, females are often attracted by high-quality territories, which are expected to be owned by males that successfully won competition with other males. Because morphological and behavioral traits frequently influence males' combat success, these parameters may be used by females to assess the male (and associated territory) quality. In the present study, we tested the hypothesis that organismal traits in dominant males of the lizard Tropidurus torquatus are associated with the quality of the territory owned. After characterizing the territories occupied, we used a discriminant analysis to test if morphological and behavioral traits of the dominant male predict the quality of the territory owned. High-quality territories were characterized by a larger number of refuges, shorter distances among shelters and a well-defined harem, in comparison with low-quality territories. Organismal traits predicted with 100% accuracy the type of the territory owned: high-quality territories were associated with larger males that had longer heads, while males occupying low-quality territories exhibited more head displays, traveled larger distances and ran slightly slower than those associated with high-quality territories. We discuss possible implications of territory quality and male traits for reproductive success in Tropidurus torquatus

    Alexithymia and mood: Recognition of emotion in self and others

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    The present study explored relationships between alexithymia—a trait characterized by difficulties identifying and describing feelings and an external thinking style—and negative moods, negative mood regulation expectancies, facial recognition of emotions, emotional empathy, and alcohol consumption. The sample consisted of 102 university (primarily psychology) students (13 men, 89 women) aged 18 to 50 years (M = 22.18 years). Participants completed the Toronto Alexithymia Scale (TAS-20), Negative Mood Regulation Scale (NMRS), Depression Anxiety Stress Scales (DASS-21), Reading the Mind in the Eyes Test (RMET), Interpersonal Reactivity Index (IRI), and Alcohol Use Disorders Identification Test (AUDIT). Results were consistent with previous findings of positive relationships of TAS-20 alexithymia scores with both alcohol use (AUDIT) and negative moods (DASS-21) and a negative relationship with emotional self-regulation as indexed by NMRS. Predicted negative associations of both overall TAS-20 alexithymia scores and the externally oriented thinking (EOT) subscale of the TAS-20 with both RMET facial recognition of emotions and the empathic concern (EC) subscale of the IRI were supported. The mood self-regulation index NMRS fully mediated the relationship between alexithymia and negative moods. Hierarchical linear regressions revealed that, after other relevant variables were controlled for, the EOT subscale of the TAS-20 predicted RMET and EC. The concrete thinking or EOT facet of alexithymia thus appears to be associated with diminished facial recognition of emotions and reduced emotional empathy. The negative moods associated with alexithymia appear to be linked to subjective difficulties in self-regulation of emotions

    Alexithymia and mood: Recognition of emotion in self and others

    Get PDF
    The present study explored relationships between alexithymia-a trait characterized by difficulties identifying and describing feelings and an external thinking style-and negative moods, negative mood regulation expectancies, facial recognition of emotions, emotional empathy, and alcohol consumption. The sample consisted of 102 university (primarily psychology) students (13 men, 89 women) aged 18 to 50 years (M = 22.18 years). Participants completed the Toronto Alexithymia Scale (TAS-20), Negative Mood Regulation Scale (NMRS), Depression Anxiety Stress Scales (DASS-21), Reading the Mind in the Eyes Test (RMET), Interpersonal Reactivity Index (IRI), and Alcohol Use Disorders Identification Test (AUDIT). Results were consistent with previous findings of positive relationships of TAS-20 alexithymia scores with both alcohol use (AUDIT) and negative moods (DASS-21) and a negative relationship with emotional self-regulation as indexed by NMRS. Predicted negative associations of both overall TAS-20 alexithymia scores and the externally oriented thinking (EOT) subscale of the TAS-20 with both RMET facial recognition of emotions and the empathic concern (EC) subscale of the IRI were supported. The mood self-regulation index NMRS fully mediated the relationship between alexithymia and negative moods. Hierarchical linear regressions revealed that, after other relevant variables were controlled for, the EOT subscale of the TAS-20 predicted RMET and EC. The concrete thinking or EOT facet of alexithymia thus appears to be associated with diminished facial recognition of emotions and reduced emotional empathy. The negative moods associated with alexithymia appear to be linked to subjective difficulties in self-regulation of emotions.This research was funded by the Bond University Faculty of Society and Desig

    The relation between presenteism, burnout syndrome and ethic leadership in scholar’s organizations

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    O objetivo deste trabalho foi descrever variáveis preditoras de presenteísmo no contexto escolar, especificamente o burnout e a liderança. Utilizaram-se questionários como instrumento de coleta de dados. Responderam aos questionários 366 professores vinculados à Secretaria de Estado de Educação do Distrito Federal. Eles trabalhavam em diferentes escolas de várias regiões do Distrito Federal. Foram testadas relações lineares e com interação. Os resultados obtidos mostraram que a exaustão emocional e a liderança ética estão relacionadas à concentração no trabalho. Contudo, não se relacionam com a perda de capacidade para completar o trabalho. Neste último, a liderança aparece como uma importante variável moderadora. Os altos níveis de exaustão emocional tendem a convergir negativamente em avaliações de liderança e presenteísmo. Este estudo contribui para a compreensão da relação entre bem-estar e produtividade e suas variáveis moderadoras, assim como aponta que a exaustão emocional no trabalho influencia a avaliação do professor.info:eu-repo/semantics/publishedVersio

    Molecular evolution of HoxA13 and the multiple origins of limbless morphologies in amphibians and reptiles

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    Developmental processes and their results, morphological characters, are inherited through transmission of genes regulating development. While there is ample evidence that cis-regulatory elements tend to be modular, with sequence segments dedicated to different roles, the situation for proteins is less clear, being particularly complex for transcription factors with multiple functions. Some motifs mediating protein-protein interactions may be exclusive to particular developmental roles, but it is also possible that motifs are mostly shared among different processes. Here we focus on HoxA13, a protein essential for limb development. We asked whether the HoxA13 amino acid sequence evolved similarly in three limbless clades: Gymnophiona, Amphisbaenia and Serpentes. We explored variation in ω (dN/dS) using a maximum-likelihood framework and HoxA13sequences from 47 species. Comparisons of evolutionary models provided low ω global values and no evidence that HoxA13 experienced relaxed selection in limbless clades. Branch-site models failed to detect evidence for positive selection acting on any site along branches of Amphisbaena and Gymnophiona, while three sites were identified in Serpentes. Examination of alignments did not reveal consistent sequence differences between limbed and limbless species. We conclude that HoxA13 has no modules exclusive to limb development, which may be explained by its involvement in multiple developmental processes

    Locomotor performance of closely related Tropidurus species: relationships with physiological parameters and ecological divergence

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    Tropidurid lizards have colonized a variety of Brazilian open environments without remarkable morphological variation, despite ecological and structural differences among habitats used. This study focuses on two Tropidurus sister-species that, despite systematic proximity and similar morphology, exhibit great ecological divergence and a third ecologically generalist congeneric species providing an outgroup comparison. We quantified jumping capacity and sprint speed of each species on sand and rock to test whether ecological divergence was also accompanied by differences in locomotor performance. Relevant physiological traits possibly associated with locomotor performance metabolic scopes and fiber type composition, power output and activity of the enzymes citrate synthase, pyruvate kinase and lactate dehydrogenase of the iliofibularis muscle - were also compared among the three Tropidurus species. We found that the two sister-species exhibited remarkable differences in jumping performance, while Tropidurus oreadicus, the more distantly related species, exhibited intermediate values. Tropidurus psamonastes, a species endemic to sand dunes, exhibited high absolute sprint speeds on sand, jumped rarely and possessed a high proportion of glycolytic fibers and low activity of citrate synthase. The sister-species Tropidurus itambere, endemic to rocky outcrops, performed a large number of jumps and achieved lower absolute sprint speed than T. psamonastes. This study provides evidence of rapid divergence of locomotor parameters between sister-species that use different substrates, which is only partially explained by variation in physiological parameters of the iliofibularis muscle

    Morphological and physiological specialization for digging in amphisbaenians, an ancient lineage of fossorial vertebrates

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    Amphisbaenians are legless reptiles that differ significantly from other vertebrate lineages. Most species dig underground galleries of similar diameter to that of the animal. We studied the muscle physiology and morphological attributes of digging effort in the Brazilian amphisbaenid Leposternon microcephalum (Squamata; Amphisbaenia), which burrows by compressing soil against the upper wall of the tunnel by means of upward strokes of the head. The individuals tested

    Digits Lost or Gained? Evidence for Pedal Evolution in the Dwarf Salamander Complex (Eurycea, Plethodontidae)

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    Change in digit number, particularly digit loss, has occurred repeatedly over the evolutionary history of tetrapods. Although digit loss has been documented among distantly related species of salamanders, it is relatively uncommon in this amphibian order. For example, reduction from five to four toes appears to have evolved just three times in the morphologically and ecologically diverse family Plethodontidae. Here we report a molecular phylogenetic analysis for one of these four-toed lineages – the Eurycea quadridigitata complex (dwarf salamanders) – emphasizing relationships to other species in the genus. A multilocus phylogeny reveals that dwarf salamanders are paraphyletic with respect to a complex of five-toed, paedomorphic Eurycea from the Edwards Plateau in Texas. We use this phylogeny to examine evolution of digit number within the dwarf−Edwards Plateau clade, testing contrasting hypotheses of digit loss (parallelism among dwarf salamanders) versus digit gain (re-evolution in the Edwards Plateau complex). Bayes factors analysis provides statistical support for a five-toed common ancestor at the dwarf-Edwards node, favoring, slightly, the parallelism hypothesis for digit loss. More importantly, our phylogenetic results pinpoint a rare event in the pedal evolution of plethodontid salamanders
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