28 research outputs found

    Comparative anatomy and development of pectoral and pelvic girdles in hylid anurans

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    The development of the tetrapod pectoral and pelvic girdles is intimately linked to the proximal segments of the fore- and hindlimbs. Most studies on girdles are osteological and provide little information about soft elements such as muscles and tendons. Moreover, there are few comparative developmental studies. Comparative data gleaned from cleared-and-stained whole mounts and serial histological sections of 10 species of hylid frogs are presented here. Adult skeletal morphology, along with bones, muscles, and connective tissue of both girdles and their association with the proximal portions of the anuran fore- and hindlimbs are described. The data suggest that any similarity could be attributable to the constraints of their ball-and-socket joints, including incorporation of the girdle and stylopodium into a single developmental module. An ancestral state reconstruction of key structures and developmental episodes reveals that several development events occur at similar stages in different species, thereby preventing heterochronic changes. The medial contact of the halves of the pectoral girdle coincides with the emergence of the forelimbs from the branchial chamber and with the total differentiation of the linkage between the axial skeleton and the girdles. The data suggest that morphogenic activity in the anterior dorsal body region is greater than in the posterior one, reflecting the evolutionary sequence of the development of the two girdles in ancient tetrapods. The data also document the profound differences in the anatomy and development of the pectoral and pelvic girdles, supporting the proposal that the pectoral and pelvic girdles are not serially homologous, as was long presumed.Fil: Soliz, Monica Carina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta; Argentina. Universidad Nacional de Salta. Facultad de Ciencias Naturales; ArgentinaFil: Ponssa, María Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; Argentina. Fundación Miguel Lillo; ArgentinaFil: Abdala, Virginia Sara Luz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biodiversidad Neotropical. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto de Biodiversidad Neotropical. Instituto de Biodiversidad Neotropical; Argentin

    May I curse a referee? Swear words and consequences

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    The purpose of this study was to determine whether male and female soccer (football) referees would execute the Laws of the Game despite players' verbal abuse. Law 12 (Fouls and misconduct) instructs the referees as to how they should react when a player, substitute or substituted player expresses a swear word. The player should be issued a red card. Referees (n = 113) were presented with 28 swear words and asked how they would respond if this situation occurred in a real game (red card, yellow/blue card [blue cards are used in juvenile games, player leaves field of game for 10 minutes], admonition, no reaction). The selected words were divided into categories (such as pertaining to intelligence or sexual abuse) indicating different degrees of insult. Approximately half of the referees would have responded to players saying swear words in a game by issuing a red card (55.7% red card, 25.2% yellow/blue card, 12.1% admonition, and 7.0% no reaction). The response was independent of the referees' qualification and experience. It was found that the insulting content of a swear word determines the referee's decision. Referees would apply Law 12 only in one half of the cases, depending on the insulting content. The findings are discussed in the context of game managemen
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