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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

BIOTECHNOLOGICAL FOUNDATIONS OF <i>SPOROBOLOMYCES LACTUCAE</i> FOR ROMAINE LETTUCE FOOD SAFETY APPLICATIONS

Samira Fatemi (17277682) 12 December 2023 (has links)
<p dir="ltr">Romaine lettuce is a vegetable crop that is frequently contaminated with and often implicated in mass outbreaks of human-pathogenic <i>Escherichia coli</i>. To date, research has focused on the specific pathogens responsible for those outbreaks and consumer- and retail-level interventions to eliminate those pathogens or to mitigate their spread. However, in many cases, no singular food source can be identified. Food microbiomes, particularly those associated phylloplanes, are a growing interest area and may be key in identifying the conditions that allow for proliferation of pathogenic organisms like <i>E. coli</i> O157:H7. Further, examination of dominant components of the lettuce microbiome may reveal suitable candidates that can be encouraged or engineered to outcompete or indicate the presence of pathogens. Until recently, most microbiome studies focused on bacteria; less understood are the fungi of these microbiomes. Many fungi have myriad applications in the prevention and mitigation of both human and plant diseases. Thus, to effectively prevent pathogenic <i>E. coli </i>outbreaks, a fundamental understanding about the fungi that cohabit the lettuce microbiome is paramount. The most frequently isolated yeast in the romaine lettuce microbiome is an undescribed yeast, revealing the dearth of information regarding nonpathogenic fungi in food systems. First, the novel yeast <i>Sporobolomyces lactucae</i> is described using a multi-locus phylogeny through genealogical gene concordance, with a discussion on the potential ecological range. Second, the genome of <i>S. lactucae </i>strain HU9244 is assembled and annotated with transcriptomic information to help guide target gene selection for biotechnology, particularly in identifying candidates for reporter genes that may assist in the detection of <i>E. coli </i>O157:H7 via olfactory or visual cues. Third, the distribution of the yeast <i>S. lactucae</i> is determined, finding the organism in various climate types and potentially on other leafy greens as well, indicating its suitability for <i>in situ</i> detection of foodborne pathogens such as <i>E. coli</i> O157:H7 commonly found on romaine lettuce and other leafy greens.</p>
2

Geographic variation in torpor patterns : the northernmost prairie dogs and kangaroo rats

Gummer, David Lee 14 April 2005
<p>Many endotherms use torpor on a seasonal or daily basis to conserve metabolic resources during difficult conditions, but the capacity to do so has never been recognized as varying intraspecifically. I hypothesized that populations that are exposed to prolonged cold, snow, or scarcity of food resources relative to other conspecifics may express torpor despite the fact that other conspecifics may not use, or even be capable of, torpor. I studied thermoregulation of black-tailed prairie dogs (<I>Cynomys ludovicianus</I>) and Ords kangaroo rats (<I>Dipodomys ordii</I>) at the extreme northernmost periphery of each species range to determine whether there is evidence for geographic variation in torpor patterns.</p><p>Contrary to previous studies of black-tailed prairie dogs near the centre of the species range, I found that northern prairie dogs hibernate during winter, spending up to 95 days per year in torpor. Synchrony of body temperature patterns of some individuals suggests that northern prairie dogs hibernate communally. Similarly, in contrast to previous studies of kangaroo rats in more southern localities, I found that northern Ords kangaroo rats use daily torpor during winter, entering torpor on up to 70 days per year. Kangaroo rats that use deep torpor exhibit comparable survival and pre-winter body mass, but poorer spring body condition, than kangaroo rats that do not use deep torpor. I reported the details of my procedures for studying thermoregulation of small mammals in the wild, to encourage comparable studies that would provide additional insights on intraspecific variation in torpor patterns. My findings are the first to demonstrate that the capacity for torpor varies predictably on a geographic basis.</p>
3

Geographic variation in torpor patterns : the northernmost prairie dogs and kangaroo rats

Gummer, David Lee 14 April 2005 (has links)
<p>Many endotherms use torpor on a seasonal or daily basis to conserve metabolic resources during difficult conditions, but the capacity to do so has never been recognized as varying intraspecifically. I hypothesized that populations that are exposed to prolonged cold, snow, or scarcity of food resources relative to other conspecifics may express torpor despite the fact that other conspecifics may not use, or even be capable of, torpor. I studied thermoregulation of black-tailed prairie dogs (<I>Cynomys ludovicianus</I>) and Ords kangaroo rats (<I>Dipodomys ordii</I>) at the extreme northernmost periphery of each species range to determine whether there is evidence for geographic variation in torpor patterns.</p><p>Contrary to previous studies of black-tailed prairie dogs near the centre of the species range, I found that northern prairie dogs hibernate during winter, spending up to 95 days per year in torpor. Synchrony of body temperature patterns of some individuals suggests that northern prairie dogs hibernate communally. Similarly, in contrast to previous studies of kangaroo rats in more southern localities, I found that northern Ords kangaroo rats use daily torpor during winter, entering torpor on up to 70 days per year. Kangaroo rats that use deep torpor exhibit comparable survival and pre-winter body mass, but poorer spring body condition, than kangaroo rats that do not use deep torpor. I reported the details of my procedures for studying thermoregulation of small mammals in the wild, to encourage comparable studies that would provide additional insights on intraspecific variation in torpor patterns. My findings are the first to demonstrate that the capacity for torpor varies predictably on a geographic basis.</p>
4

Padrões distribucionais das espécies da família Leucosiidae Samouelle (1919) (Crustacea: Decapoda: Brachyura) no Atlântico ocidental baseados na distribuição potencial e análise de parcimônia de endemismo / Distributional patterns of species of the family Leucosiidae Samouelle (1919) (Crustacea: Decapoda: Brachyura) in the western Atlantic based on potential distribution and parsimony analysis of endesmism

Castro, Nataly Almeida de 27 March 2012 (has links)
The Brazilian coast holds 21 species of crabs from the Leucosiidae family, being an interesting group for biogeographical studies. This work gathered 531 occurrence points from these species. This data survey was done to allow the usage of a predictive modeling technique implemented by Maxent software, in order to estimate the species geographical distribution. Those models were then subject of a Parsimony endemism analysis. Maps from the potential distribution of 15 species from this family were generated and used to determine biogeographical distributional patterns, that indicated an endemism area at the western Atlantic ocean, that was also considered a secondary dispersion center. Even though predictive modeling was never used before at continental shelf environments, it proved to show results that match the species distributional limits proposed in previous studies. / Os caranguejos da família Leucossidae possuem 21 espécies distribuídas na plataforma continental da costa brasileira, e representam um interessante grupo para estudos de biogeografia. Para a realização deste trabalho, foram avaliados 531 pontos de ocorrência de espécies desta família. Este levantamento foi feito com o intuito de estimar a distribuição geográfica das espécies, e para isto a técnica de modelagem preditiva foi utilizada, através do programa Maxent. A fim de maximizar os resultados, foram analisadas dentre as áreas de ocorrência quais seriam centro de endemismo utilizando a Análise de Parcimônia de Endemismo. Quinze espécies da família foram modeladas originando mapas de distribuição potencial, que por fim determinaram padrões de distribuição biogeográficos e apontaram uma área de endemismo no Atlântico ocidental, além de considerar esta porção do oceano, como um centro de dispersão secundário. Apesar da modelagem preditiva nunca ter sido utilizada em ambientes marinhos de plataforma continental, a mesma se mostrou coerente com estudos anteriores na determinação de limites de distribuição das espécies.q
5

Evidence of White Pine (Pinus subgenus Strobus) Dominance From the Pliocene Northeastern Gulf of Mexico Coastal Plain

Stults, Debra Z., Axsmith, Brian J., Liu, Yu Sheng C. 01 March 2010 (has links)
Plant fossils from the Citronelle Formation provide a rare window into the Pliocene flora and climate of the northeastern Gulf of Mexico Coastal Plain. Many of the taxa recovered to date inhabit the region today. However, analysis of Pinus pollen grains and fascicles indicates that the dominant pines were members of Pinus subgenus Strobus (i.e., "white pines"). The fascicles have a small, bulbous base lacking a sheath, and bear four or five long, slender needles. These features are typical of white pines. Although macrofossils are rare, 77 to 100% of the dispersed Pinus pollen grains from five localities have sacci continuous with the corpus and verrucae on the cappula, which are characteristics of white pines. This is remarkable, as the northeastern Gulf of Mexico Coastal Plain today is devoid of white pines, and is instead considered a center of diversity for Pinus subgenus Pinus section Pinus subsection Australes. Today, Pinus strobus is the only white pine in the eastern North America and its southernmost distribution only extends into the mountains of Georgia, about 600 km north of the fossil sites. The historical biogeographic relationships of P. strobus to other North American forms are unclear. For example, its close relative, Pinus chiapensis, is present in northeastern Mexico and Central America. The current disjunction between P. strobus and P. chiapensis is 2400 km and includes an arid barrier to dispersal. P. chiapensis is also associated with several other species showing a similar biogeographic pattern. The fossils described here indicate that white pines were more widespread in North America in the recent geological past than previously thought, and imply possible connections between disjunct species that would not be suspected if only current species' ranges and ecological tolerances were considered.
6

Prediction of self-compacting concrete elastic modulus using two symbolic regression techniques

Golafshani, E.M., Ashour, Ashraf 28 December 2015 (has links)
yes / This paper introduces a novel symbolic regression approach, namely biogeographical-based programming (BBP), for the prediction of elastic modulus of self-compacting concrete (SCC). The BBP model was constructed directly from a comprehensive dataset of experimental results of SCC available in the literature. For comparison purposes, another new symbolic regression model, namely artificial bee colony programming (ABCP), was also developed. Furthermore, several available formulas for predicting the elastic modulus of SCC were assessed using the collected database. The results show that the proposed BBP model provides slightly closer results to experiments than ABCP model and existing available formulas. A sensitivity analysis of BBP parameters also shows that the prediction by BBP model improves with the increase of habitat size, colony size and maximum tree depth. In addition, among all considered empirical and design code equations, Leemann and Hoffmann and ACI 318-08’s equations exhibit a reasonable performance but Persson and Felekoglu et al.’s equations are highly inaccurate for the prediction of SCC elastic modulus.
7

Diversity of the genus Trichomycterus Valenciennes, 1832 (Siluriformes, Trichomycteridae) in the Rio Doce basin: a systematic study integrating phenotypes, DNA and classical taxonomy / Diversidade do gênero Trichomycterus Valenciennes, 1832 (Siluriformes, Trichomycteridae) na bacia do Rio Doce: um estudo sistemático integrando fenótipos, DNA e taxonomia clássica.

Reis, Vínicius José Carvalho 21 September 2018 (has links)
The diversity of the genus Trichomycterus Valenciennes 1832 in the Rio Doce basin is investigated using conventional and modern morphology and DNA analyses. The work is presented in two Chapters. Chapter One, entitled Diversity of the genus Trichomycterus Valenciennes, 1832 (Siluriforms, Trichomycteridae) in the Rio Doce basin: a systematic study integrating phenotypes, DNA and classical taxonomy integratively analyzes specimens of the genus from the entire Rio Doce drainage and adjacent basins, both from available world-wide collections and from active sampling efforts. A combination of phenotypic and DNA (COI barcoding analysis) provides evidence for the existence of 14 species in the basin, 10 of which are new: T. alternatus Eigenmann, 1917; T. argos Lezama et al., 2012; T. astromycterus sp. nov.; T. barrocus sp. nov.; T. brucutu sp. nov.; T. brunoi Barbosa & Costa, 2010; T. immaculatus (Eigenmann & Eigenmann, 1889)] T. illuvies sp. nov.; T. melanopygius sp. nov.; T. ipatinguensis sp. nov.; T. pussilipygius sp. nov.; T. sordislutum sp. nov.; T. vinnulus sp. nov; and T. tantalus sp. nov. . In addition, a lectotype is designated for T. immaculatus and the species is considered as a senior synonym of Trichomycterus pradensis Sarmento-Soares et al., 2005. Although remarkable, such increase in species number of Trichomycterus in a single drainage matches similar recent increments in some other Southeastern Brazilian basins, such as the Paraíba do Sul and Iguaçu. The kind of differentiation among species herein recognized varies, with some of them being well-differentiated in morphology but not in barcoding data, and others showing the opposite phenomenon. The geographical distribution of each of the 14 species is plotted in the Rio Doce basin. The wide geographical distribution of some species (T. alternatus and T. immaculatus) is explained against data from geomorphological processes and comparative information on their biology. Chapter two, The type specimens of Trichomycterus alternatus (Eigenmann, 1917) and T. zonatus (Eigenmann, 1918), with elements for future revisionary work (Teleostei, Siluriformes, Trichomycteridae) focuses on the complex taxonomy, nomenclature and type material status of T. alternatus and T. zonatus. The type series of the two species are analyzed in detail, both in morphology and locality data. Osteological information was obtained with conventional and a new technique of radiographic stereo-triplets. Our new data elucidates their species distinctiveness, diagnostic characteristics, type localities and show that T. zonatus does not occur in the Rio Doce basin. / A diversidade do gênero Trichomycterus Valenciennes 1832 na bacia do Rio Doce é investigada utilizando métodos convencionais e modernos em análises morfológicas e moleculares. Os resultados desta dissertação são apresentados em dois capítulos. Capítulo um, intitulado Diversity of the genus Trichomycterus Valenciennes, 1832 (Siluriforms, Trichomycteridae) in the Rio Doce basin: a systematic study integrating phenotypes, DNA and classical taxonomy examinou espécimes pertencentes a este gênero encontrados no Rio Doce e em bacias adjacentes disponíveis em coleções nacionais e internacionais e coletados durante esta dissertação. O conjunto de dados obtidos através de análises morfológicas e moleculares (COI, DNA barcoding) revelou a existência de 14 espécies na bacia do Rio Doce, das quais 10 novas: T. alternatus Eigenmann, 1917; T. argos Lezama et al., 2012; T. astromycterus sp. nov.; T. barrocus sp. nov.; T. brucutu sp. nov.; T. brunoi Barbosa & Costa, 2010; T. immaculatus (Eigenmann & Eigenmann, 1889)] T. illuvies sp. nov.; T. melanopygius sp. nov.; T. ipatinguensis sp. nov.; T. pussilipygius sp. nov.; T. sordislutum sp. nov.; T. vinnulus sp. nov; and T. tantalus sp. nov. Além disso, é designado um lectótipo para T. immaculatus, espécie aqui proposta como sinônimo sênior de Trichomycterus pradensis Sarmento-Soares et al., 2005. O acentuado incremento em número de espécies de Trichomycterus para uma única bacia segue um padrão de crescimento em biodiversidade conhecida do gênero para outras drenagens do sudeste brasileiro a exemplo do rio Paraíba do Sul e Iguaçu. Os tipos de diferenciação detectada entre as espécies aqui tratadas variam, com algumas bem corroboradas morfologicamente, porém muito similares ou indiferenciáveis em análise de DNA barcoding, e outras apresentando o fenômeno oposto. As distribuições geográficas de cada uma das 14 espécies são mapeadas com base em todo o material examinado. A ampla distribuição geográfica de algumas espécies (T. alternatus and T. immaculatus) é explicada através de processos geomorfológicos e informações comparativas sobre suas biologias. O capítulo dois, The type specimens of Trichomycterus alternatus (Eigenmann, 1917) and T. zonatus (Eigenmann, 1918), with elements for future revisionary work (Teleostei, Siluriformes, Trichomycteridae) se concentra em esclarecer a complexa taxonomia, nomenclatura e o status do material tipo de T. alternatus e T. zonatus. As séries tipos das duas espécies foram minuciosamente analisadas tanto para morfologia como para suas respectivas localidades de proveniência. Informações osteológicas foram obtidas através de técnicas de radiografia convencionais e uma nova metodologia chamada stereo triplets. Os dados obtidos corroboram as respectivas espécies como distintas, e permitem uma avaliação precisa de seus respectivos caracteres diagnósticos e localidades tipo. Também se chegou à conclusão que T. zonatus não ocorre na bacia do Rio Doce.
8

Les coccinelles algériennes (Coleoptera, Coccinellidae) : analyse faunistique et structure des communautés / Algerian ladybirds (Coleoptera, Coccinellidae) : a faunistic analysis and community structure study

Saharaoui, Lounes 11 December 2017 (has links)
L'étude menée durant quatre années consécutives (2003-2007) a caractérisé écologiquement et faunistiquement le peuplement des coccinelles en Algérie. 48 espèces ont été répertoriées dont 46 sont des agents de lutte biologiques. Elles se répartissent dans huit sous-familles, 12 tribus et 23 genres. La richesse spécifique est très élevée dans les secteurs du nord d'Algérie. Cette zone est caractérisée par des bioclimats humide, sub-humide et semi aride regroupant 41 espèces. Elle est par contre très faible dans le secteur de l'Atlas saharien et le Sud algérien avec respectivement 12 et 16 espèces. L'étude des spécificités trophiques, spatiales et temporelles des principales espèces, nous a conduits à définir leurs niches écologiques dans les différents agro écosystèmes de l'Algérie. Ainsi, la distribution spatiale des espèces peut apparaître comme quelque chose de statique. Il s'agit en réalité d'un processus dynamique dont le moteur est la disponibilité d'habitat favorable qui abrite la proie préférentielle. La communauté de coccinelles fonctionne sur le principe de partage des ressources et les interactions entre espèces organisent la communauté en réseaux trophiques. L'analyse de la distribution des coccinelles à travers les différents secteurs géographiques montre que les espèces: C. septempunctata, H. variegata, S. punctillum et, H. argus présentent une forte valence écologique. En revanche, les espèces: P. ovoideus, P. numidicus, E. pubescent forme apicalis, H. marmottani, et Pullus sp semblent être spécifiques aux régions sahariennes et plus particulièrement au Sahara septentrional. / The study led during four consecutive years (on 2003-2007) shed light on the species composition, and habitat characteristics of the communities of ladybirds in Algeria. 48 species were listed among which 46 are biological control agents. They divide up in 8 sub-families, 12 tribes and 23 genera. The specific richness is very high in the sectors of the North of Algeria (41 species). This zone is characterized by bioclimates wet, sub-wet and semi-dry grouping. It is very low on the other hand in the sector of the Saharan Atlas and the Algerian South with respectively 12 and 16 species. The study of trophic interactions, spatial and temporal distribution of the main species, led us to define their ecological niches in the various agro-ecosystems of Algeria. So, the spatial distribution of the species can appear as something static. It is in reality a dynamic process the engine of which is the availability of favorable habitats that shelter ladybird preferential prey. Communities of ladybird works on the principle of division (sharing) of the resources and the interactions between species organize the community in trophic networks. The analysis of the distribution of ladybirds through the various geographical areas shows that the C. septempunctata, H. variegata, S. punctillum, and, H. argus present strong ecological valence. On the other hand, P. ovoideus, P. numidicus, E. pubescens forme apicalis, H. marmottani, and Pullus sp are specific to the Saharan regions and more particularly to northern Sahara.
9

BIOGEOGRAFIA DA ESTEPE DOS CAMPOS GERAIS DO PARANÁ

Rosa, Marina Comerlatto da 04 December 2015 (has links)
Made available in DSpace on 2017-07-21T18:15:20Z (GMT). No. of bitstreams: 1 Marina Comerlatto da Rosa.pdf: 4715462 bytes, checksum: 33d2627d4f49c3c39739ca7d9ddb777b (MD5) Previous issue date: 2015-12-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / ‘Souhtern Grasslands’ is the biogeographical term assigned by the Brazilian Governmentto the natural field extensions present in the Mata Atlântica and Pampa Domains that correspond to the biogeographical provinces ‘Paranaense’ and ‘Pampeana’, respectivelly. The spatial delineation of the Campos District in the Paranaense Province, within the southern portion of the Atlantic Forest Domain comprises the native grasslands of State of Parana (‘Campos Gerais’, ‘Campos de Guarapuava’ and ‘Campos de Palmas’) Santa Catarina (‘Campos de Palmas’ / ‘Água Doce’ and ‘Planalto de Lages’), and Rio Grande do Sul (‘Campos de Cima da Serra’). Despite their homogeneous appearance, ‘Souhtern Grasslands’ may show significant differences in their composition depending on the environmental conditions and the evolution of the flora in the two provinces involved. In this sense, to elucidate the biogeographic relationships of native grasslands of the ‘Campos Gerais’ in Paranaense Province means establish whether the plant communities comprise marginal areas of geographic scale or, conversely, compound species dispersal center, or even species routes from dispersion centers out of ‘Campos Gerais’. This study therefore aims to determine the biogeographical relationships among remnants of native grasslands in the Escarpa Devoniana Environmental Protection Area. For this, we used a presence/absence matrix composed by 414 species from phytosociological data, and 1,375 species from floristic surveys from nine plant communities: CPI - Piraí da Serra, EGU - Guartelá State Park, SJ – São João River, CPG - Pitangui Valley, CAP – Capão da Onça, FG / BP - Furnas Gêmeas and Buraco do Padre, CIA - IAPAR Model Farm, EVV - Vila Velha State Park, and CBN – Ponte dos Arcos. Just two of them are within protect areas. It were calculated the Biogeographycal Similarity Coefficient as well Harrison and Wilson & Schmida beta diversity indices. Once there was lack of spatial autocorrelation (Moran Correlogram), for the floristic similarity calculation we used multivariate statistical analysis. The contemporary vegetation is a confluence between marginal areas of the geographical range of southern grasslands and northern subtropical savannah (Cerrado Domain). There were no evidences of this region as a dispersion center nor corridor between other dispersion centers in the Mata Atlântica Domain. Ecotonal areas lead to biodiversity increase as well point out their extreme vulnerability to climate or anthropogenic disturbances. / Campos Sulinos é o termo biogeográfico atribuído pelo Ministério do Meio Ambiente às extensões campestres presentes nos biomas Mata Atlântica e Pampa, correspondendo às províncias biogeográficas Paranaense e Pampeana, respectivamente. A delimitação espacial fitofisionômica do Distrito dos Campos na Província Paranaense, contida integralmente na porção austral do Bioma Mata Atlântica compreende os campos nativos do Estado do Paraná (Campos Gerais, Campos de Guarapuava e Campos de Palmas) Santa Catarina (Campos de Palmas /Água Doce e Planalto de Lages) e Rio Grande do Sul (Campos de Cima da Serra). Apesar da aparência homogênea, os Campos Sulinos podem apresentar expressivas diferenças em sua composição, dependendo das condições ambientais e da evolução da flora nas duas províncias envolvidas. Neste sentido, elucidar as relações biogeográficas dos campos nativos dos Campos Gerais na Província Paranaense, envolveu estabelecer se as fitocenoses constituem área marginal de amplitude geográfica ou, ao contrário, centro de dispersão de espécies, ou ainda rotas percorridas por espécies oriundas de centros de dispersão fora dos Campos Gerais. Este estudo pretende, portanto, determinar as relações biogeográficas a partir de remanescentes de campos nativos contidos na APA da Escarpa Devoniana. Para tanto, utilizou-se uma matriz de presença/ausência composta por 414 espécies oriundas de dados fitossociológicos e 1.375 espécies constantes de levantamentos florísticos de nove fitocenoses: CPI - Piraí da Serra, EGU - Parque Estadual do Guartelá, SJ - rio São João, CPG - Vale do Pitangui e Alagados, CAP - Capão da Onça, FG/BP - Furnas Gêmeas e Buraco do Padre, CIA - Fazenda Modelo do IAPAR, EVV - Parque Estadual de Vila Velha e CBN - Ponte dos Arcos, sendo duas em unidades de conservação de proteção integral. Calculou-se o Coeficiente de Semelhança Biogeográfica bem como os índices de diversidade beta de Harrison e de Wilson e Schmida. Verificada a inexistência de autocorrelação espacial entre as fitocenoses (Correlograma de Moran), para o cálculo de similaridade florística utilizou-se análise estatística multivariada. Os campos nativos na região constituem a confluência ecotonal das áreas marginais de amplitude geográfica setentrional da Estepe gramíneo-lenhosa e austral da Savana gramíneo-lenhosa (Bioma Cerrado). Não foram encontradas evidências que suportem a região como sendo centro de dispersão de espécies, tampouco corredor entre dois centros de dispersão no Bioma Mata Atlântica. Áreas ecotonais propiciam um aumento na biodiversidade ao mesmo tempo que apontam comunidades em extrema vulnerabilidade a distúrbios climáticos ou antrópicos.
10

Diversidade evolutiva de morcegos: padrões geográficos e aplicações em conservação / Evolutive diversity of bats: geographic patterns and conservation applications

Peixoto, Franciele Parreira 18 March 2013 (has links)
Submitted by Erika Demachki (erikademachki@gmail.com) on 2014-09-23T21:19:16Z No. of bitstreams: 2 Peixoto, Franciele Parreira-Dissertação-2013.pdf: 995120 bytes, checksum: 365969ffce47a58af2a011eb0370ed04 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2014-09-23T21:58:54Z (GMT) No. of bitstreams: 2 Peixoto, Franciele Parreira-Dissertação-2013.pdf: 995120 bytes, checksum: 365969ffce47a58af2a011eb0370ed04 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-09-23T21:58:54Z (GMT). No. of bitstreams: 2 Peixoto, Franciele Parreira-Dissertação-2013.pdf: 995120 bytes, checksum: 365969ffce47a58af2a011eb0370ed04 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2013-03-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Aim: To investigate global patterns of phylobetadiversity (PBD) in bats, with the purpose to better understand the mechanisms underlying current biodiversity patterns. We also aimed to use a metric that allows partitioning PBD into two components to distinguish the relative roles of local (e.g. lineage filtering) and regional processes (e.g. speciation) in shaping broad-scale patterns of PBD. Furthermore, we analyzed the distance-decay relationship of phylogenetic beta diversity to provide more information about factors that act in the PBD patterns. Location: global, delimited by biogeographic regions. Methods: Using the global distribution of bats and a supertree available for most species, we calculated PBD using the complement of phylosor index. We used a null model to test if two assemblages were more or less phylogenetically dissimilar than expected by chance. In addition, we decoupled PBD into turnover and nestednessresultant components, providing information about two factors that produce differences in assemblage phylogenetic composition. We also performed a Mantel analysis to analyze the distance-decay patterns of PBD and its two components. Results: The most striking difference in PBD was found between the Old and New World “phylogenetic composition”. We found the lowest values of PBD between adjacent regions (i.e., Neotropical/Neartic; Indo-Malay/Paleartic), revealing a strong geographical structure in PBD. These values were even lower when the turnover component was analyzed, demonstrating the differences in the role of regional processes in shaping regional diversity. On the other hand, we found out that for some adjacent regions (e.g., Afrotropical/Paleartic), the observed PBD was higher than expected by chance and comparatively different from expected by the distance decay relationship. This value remained high, even when we analyzed just the PBD turnover component. This demonstrates that although these regions are relatively close in space, there are other factors driving phylogenetic differences between them (e.g. an environmental barrier). Main conclusions: Our analyses revealed differences in the expected patterns of bat PBD among regions, suggesting that at broad scales, besides the effects of distance and geographic barriers, we also have to consider the importance of environmental gradients when studying the phylogenetic origin of bat assemblages. / A abordagem mais comum no uso de PD (diversidade filogenética) para conservação é selecionar locais com maior diversidade evolutiva. Essa estratégia parte do pressuposto de que locais com maior quantidade de PD indicam maior potencial para respostas evolutivas a mudanças ambientais futuras. No entanto, há um crescente debate sobre se as prioridades de conservação deveriam também ser voltadas para locais com baixo valor de PD, que podem representar centros de diversificação de espécies ou “berçários de diversidade”. Alguns trabalhos têm testado se os hotspots globais de biodiversidade, baseados em riqueza, também representam locais de desproporcional concentração de história evolutiva. Nós testamos aqui se os hotspots contêm mais, menos ou igual diversidade filogenética (PD) que o esperado por uma amostragem ao acaso de espécies em qualquer posição na filogenia, para a ordem Chiroptera. Buscamos responder qual a real contribuição de cada hotspot para a conservação de padrões e processos relacionados à diversidade filogenética. Nós utilizamos uma supertree disponível para a maioria das espécies da ordem, e dados de distribuição das espécies. Nós calculamos o PD para cada hotspot separadamente e utilizamos um modelo nulo para obter os valores esperados dado a riqueza. De 34 hotspots, apenas um apresentou maior PD do que o esperado, treze apresentaram valores menores e o restante valores iguais ao esperado. Nós demonstramos que a relação entre PD e riqueza varia entre regiões biogeográficas, de modo que não há como fazer generalizações acerca da contribuição dos hotspots para a conservação de diversidade evolutiva. De modo geral nossos resultados demonstram que devido ao fato da história evolutiva variar regionalmente, também devem ser estabelecidas as prioridades de conservação nessa escala.

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