977 resultados para Evolution, historical biogeography, Senecio, Afrotropic, Palaearctic


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Biodiversity is unequally spread throughout terrestrial ecosystems. The highest species richness of animals and plants is encountered around the Equator, and naturalists observe a decrease in the number of creatures with increasing latitude. Some animal groups, however, display an anomalous species richness pattern, but these are exceptions to the general rule. Crane flies (Diptera, Tipuloidea) are small to large sized, non-biting nematoceran insects, being mainly associated with moist environments. The species richness of crane flies is highest in the tropics, but these insects are species rich and abundant in all biogeographic realms, boreal and arctic biomes included. The phylogeny and systematics of crane flies are still at an early stage and somewhat controversial. New species are constantly discovered even from temperate Europe, faunistically the best known continent. Crane flies have been rather neglected group of insects in Finland. The history of Finnish crane fly taxonomy and faunistics started in 1907, the year when Carl Lundström published his two first articles on tipuloids. Within roughly 100 years there have been only a handful of entomologists studying the Finnish fauna, and the species richness and natural history of these flies have remained poorly understood and mapped. The aim of this thesis is to clarify the taxonomy of Finnish crane flies, present an updated and annotated list of species and seek patterns in regional species richness and assemblage composition. Tipula stackelbergi Alexander has been revised (I). This species was elevated to a species rank from a subspecific rank under T. pruinosa Wiedemann and T. stackelbergi was also deleted from the list of European crane flies. Two new synonyms were found: T. subpruinosa Mannheims is a junior synonym of T. freyana Lackschewitz and T. usuriensis Alexander is a junior synonym of T. pruinosa. A new species Tipula recondita Pilipenko & Salmela has been described (II). Both morphology and COI (mtDNA) sequences were used in the assessment of the status of the species. The new species is highly disjunct, known from Finland and Russian Far East. A list of Finnish crane flies was presented, including the presence of species in the Finnish biogeographical provinces (III). A total of twenty-four species were formally reported for the first time from Finland and twenty-two previously reported species were deleted from the list. A short historical review on the studies of Finnish crane flies has been provided. The current list of Finnish species consists of 338 crane flies (IV, Appendix I). Species richness of all species and saproxylic/fungivorous species is negatively correlated with latitude, but mire-dwelling species show a reversed species richness gradient (i.e. an increase in the number of species toward north). Provincial assemblages displayed a strong latitudinal gradient and faunistic distance increased with increasing geographical distance apart of the provinces. Nearly half (48 %) of the Finnish crane flies are Trans-Palaearctic, roughly one-third (34 %) are West Palaearctic and only 16 and 2 % are Holarctic and Fennoscandian, respectively. Due to the legacy of Pleistocene glaciations, endemic Fennoscandian species are problematic and it is thus concluded that there are probably no true endemic crane flies in this region. Finally, there are probably species living within Finnish borders that have hitherto remained unnoticed. Based on subjective assessment, the number of “true” (i.e. recorded + unknown species) species count of Finnish crane flies is at minimum 350.

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Calyptommatus and Nothobachia genera of gymnophthalmid lizards are restricted to sandy open habitats on Sao Francisco River margins, northeastern Brazil. Phylogenetic relationships and geographic distribution of the four recognized species of Calyptommatus were analyzed from partial mitochondrial cyt b, 12S, and 16S rRNA genes sequencing, taking allopatric populations of the monotypic Nothobachia ablephara as the outgroup. In Calyptommatus a basal split separated C. sinebrachiatus, a species restricted to the eastern bank of the river, from the three other species. In this clade, C. confusionibus, found on western margin, was recovered as the sister group of the two other species, C. leiolepis and C. nicterus, from opposite margins. According to approximate date estimations, C. sinebrachiatus would have separated from the other congeneric species by 4.4-6.5 my, and C. nicterus, also from eastern bank, would be diverging by 1.8-2.6 my from C. leiolepis, the sister species on the opposite margin. C. confusionibus and C. leiolepis, both from western sandy areas, would be differentiating by 2.8-5.0 my. Divergence times of about 3.0-4.0 my were estimated for allopatric populations of Nothobachia restricted to western margin. Significant differences in 16S rRNA secondary structure relatively to other vertebrates are reported. Distinct evolutionary patterns are proposed for different taxa in those sandy areas, probably related to historical changes in the course of Sao Francisco River. (C) 2010 Elsevier Inc. All rights reserved.

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The mammalian scapula is a complex morphological structure, composed of two ossification plates that fuse into a single structure. Most studies on morphological differentiation in the scapula have considered it to be a simple, spatially integrated structure, primarily influenced by the important locomotor function presented by this element. We used recently developed geometric morphometric techniques to test and quantify functional and phylogenetic influences on scapular shape variation in fossil and extant xenarthran mammals. The order Xenarthra is well represented in the fossil record and presents a stable phylogenetic hypothesis for its genealogical history. In addition, its species present a large variety of locomotor habits. Our results show that approximately half of the shape variation in the scapula is due to phylogenetic heritage. This is contrary to the view that the scapula is influenced only by functional demands. There are large-scale shape transformations that provide biomechanical adaptation for the several habits (arboreality, terrestriality, and digging), and small scale-shape transformations (mostly related to the coracoid process) that are not influenced by function. A nonlinear relationship between morphometric and phylogenetic distances indicates the presence of a complex mixture of evolutionary processes acting on shape differentiation of the scapula. J. Morphol. 241,251-263, 1999. (C) 1999 Wiley-Liss, Inc.

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As drenagens costeiras do leste do Brasil correspondem a áreas de grande significado biogeográfico, apresentando um alto grau de endemismo em sua fauna de peixes. Padrões filogenéticos sugerem uma relação próxima entre os rios que correm para o Atlântico a os adjacentes das terras altas do escudo cristalino. Entretanto, pouco tem sido dito sobre a dinâmica dos processos geológicos relacionados aos eventos cladogenéticos entre estas áreas. Padrões de distribuição e filogenéticos sugerem uma íntima associação com a história geológica da margem continental passiva da América do Sul, desde o Cretáceo aos dias atuais. Soerguimentos macrodômicos, rifteamento, movimentos verticais entre blocos falhados e o recuo erosivo da margem leste sul-americana são considerados como as principais forças geológicas atuando sobre a distribuição da ictiofauna de água doce nestas áreas. A atividade tectônica associada à ruptura do Gondwana e separação da América do Sul e África criou seis megadomos que são responsáveis por configurar a maior parte do atual curso das principais bacias hidrográficas do escudo cristalino. Com exceção das bacias localizadas às margens de tais megadomos, estes rios desenvolveram longos e sinuosos circuitos sobre o antigo escudo cristalino brasileiro antes de desaguarem no então recentemente aberto Oceano Atlântico. Eventos cladogenéticos iniciais entre drenagens de terras altas do escudo cristalino e tributários do Atlântico podem estar associados com processos vicariantes desta fase inicial, e alguns táxons antigos, basais, grupos-irmão de táxons muito inclusivos e de ampla distribuição são encontrados nestas bacias hidrográficas. Mais tarde, a denudação erosiva generalizada resultou em um ajuste isostático da margem leste da plataforma. Tal ajuste, concomitantemente a reativações de antigas zonas de falha, resultou em movimentos verticais entre blocos falhados, dando origem, no sudeste do Brasil, a bacias tafrogênicas. Tais bacias, como a de Taubaté, São Paulo, Curitiba e Volta Redonda, entre outras, capturaram drenagens e fauna de terras altas adjacentes. Os peixes fósseis da Formação Tremembé (Eoceno-Oligoceno da Bacia de Taubaté) exemplificam este processo. Outros sistemas tafrogênicos de idade Terciária foram também identificados em outros segmentos da margem continental Atlântica, como na Província Borborema, no NE do Brasil, com marcada influência sobre o padrão de drenagem. Ao mesmo tempo, o recuo erosivo da margem leste da plataforma capturou sucessivamente rios de planalto, os quais se tornaram tributários atlânticos, evoluindo associados aos principais sistemas de falha. A natureza continuada destes processos explica os padrões filogenéticos e de distribuição miscigenados entre os tributários atlânticos e as terras altas do escudo cristalino adjacente, especialmente na margem sudeste do continente, representados por sucessivos, cada vez menos inclusivos, grupos irmãos, associados a eventos cladogenéticos desde o final do Cretáceo ao presente.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Dental ceramics are presented within a simplifying framework allowing for facile understanding of their development, composition and indications. Engineering assessments of clinical function are dealt with and literature is reviewed on the clinical behaviour of all-ceramic systems. Practical aspects are presented regarding the choice and use of dental ceramics to maximize aesthetics and durability, emphasizing what we know and how we know it.

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In Brazil, a policy on citizen participation and consultation in urban intervention programs, in particular in the development of master plans, was first introduced into the Federal Constitution in 1988. This article presents an historical reconstitution of Master Plans in Bauru – State of São Paulo – Brazil. The 1968, 1988 and 2005/2006 consultation methods are analyzed using established criteria. The degree of community participation in the processes is estimated by drawing on a typology based on the level of involvement by residents. The effects of participation caused by changes in political regime, technical planning vision, legal support to consultation, recognition of community importance and knowledge acquired during the process are highlighted and discussed.

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This thesis will cover sports controversies throughout the 20th Century in the context of the media’s newspaper coverage of the events. The 1919 Black Sox Scandal, the debate over American participation in the 1936 Olympics, and Muhammad Ali’s conversion to the Nation of Islam, standing as a notorious public figure, and conscientious objection to the Vietnam War will represent the three sports controversies. The media’s adherence to cultural norms is clear in all three cases. The consistent devotion to the cultural and racial atmosphere of their respective eras was constant and helped to perpetuate accepted, mainstream cultural attitudes. Cultural and racial norms were followed in the coverage of the three discussed controversies. The anti-Semitism and racially intolerant sentiments in America during great waves of immigration in the early 1900s allowed for journalists to freely vilify Jews as corrupters of baseball and the ballplayers who were rumored to have thrown the 1919 World Series. The white ballplayers were supported in the press, who protected their own and blamed outsiders. Jim Crow and the Americanization movement forced African American and Jewish newspapers to limit their journalistic bias on both sides of the debate over American participation in the 1936 Berlin Olympics. The white, mainstream press was void of bias as the spirit of isolationism in America triumphed over journalist’s leanings in the Olympic debate. The racial tension created by the Civil Rights movement of the 1960s created an atmosphere that allowed mainstream journalists to heap endless criticism on Muhammad Ali as he gained fame. By portraying him as a villain of society as both a religious radical and traitor to America, journalists created a common enemy in the minds of white America. In all three cases, a pattern of journalists expressing the state of cultural and racial norms of the era is present and significant.