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SMALL MAMMAL POPULATIONS IN SWITCHGRASS STANDS MANAGED FOR BIOMASS PRODUCTION COMPARED TO HAY AND CORN FIELDS IN KENTUCKYSchwer, Laura Mary Jane 01 January 2011 (has links)
Switchgrass (Panicum virgatum), a native warm-season grass, has been investigated as a renewable energy crop that may provide viable wildlife habitat. This study investigated small mammal populations in switchgrass, hay, and corn to assess the relative habitat quality. Four, three-night trapping sessions were conducted at four locations in Kentucky using Sherman livetraps. Trapping occurred in spring (before first hay harvest), summer, fall (before switchgrass and corn harvest), and winter (post-harvest). Relative abundance of small mammals, calculated using a capture per unit effort index (per 100 trapnights), and mean taxonomic richness were used to compare habitats. Switchgrass had a significantly greater mean taxonomic richness than hay but not corn; however, four genera were captured in switchgrass and only two in corn. Switchgrass had a greater relative abundance of small mammals than hay during the summer, and corn and hay during the fall. Vegetative cover was positively correlated with relative abundance of small mammals. No-till corn and three year old switchgrass had a greater relative abundance of small mammals than conventionally tilled corn and two year old switchgrass, respectively. In conclusion, switchgrass stands managed as a renewable energy crop has the potential to be viable wildlife habitat for some small mammal species.
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Biogeografijos metodų taikymas aplinkos geografiniuose tyrimyose ir edukacijoje / The application of biogeographical methods in geographical environment researches and educational systemPastarnokas, Simonas 23 July 2014 (has links)
Mgagistro darbo tema: Biogeografijos metodų taikymas aplinkops geografiniuose tyrimuose ir edukacijoje. Šiame, baigiamajame magistro darbe išsamiai aprašoma smulkiųjų žinduolių tyrimų vieta ir gaudymo metodika gyvagaudžiais spąstais. Pateikiama bendra Neries regioninio parko, Dūkšto ąžuolyno, Šeškinės ozo charakteristika. Aprašoma įvairių pelinių graužikų ir vabzdžiaėdžių žinduolių morfologinis apibūdinimas, esminiai biologijos bruožai. Atlikta smulkiųjų žinduolių gaudymo rezultatų analizė 2010 ir 2011 metais, įvairiose buveinėse. Atlikus duomenų analizę 2010 ir 2011 metais. Dūkšto ąžuolyne bei Šeškinės oze šiltuoju metų laiku buvo aptikti 3-jų rūšių vabzdžiaėdžiai žinduoliai (paprastasis kirstukas, kirstukas nykštukas, vandeninis kirstukas) ir 8 rūšių peliniai graužikai (rudasis pelėnas, paprastasis pelėnas, pievinis pelėnas, pelkinis pelėnas, dirvinė pelė, geltonkaklė pelė, pelė mažylė ir pilkoji žiurkė). Išanalizavus 2010 – 2011 metų duomenis Dūkšto ąžuolyne ir Šeškinės oze skirtingose buveinėse, pastebimas smulkiųjų žinduolių įvairovės ir gausos didėjimas vasaros pabaigoje, o ypač rugsėjo mėnesį. Rugsėjo mėnesį įvairovės ir gausos duomenys buvo patys didžiausi. Dominuojanti rūšis tiek Dūkšto ąžuolyne, tiek Šeškinės oze, įvairiose buveinėse buvo rudasis pelėnas, jo buvo pagauta daugiausiai iš visų gaudytų pelinių graužikų ir vabzdžiaėdžių žinduolių. / Master‘s thesis: „The application of biogeographical methods in geographical environment researches and educational system“. This final masters work has a detailed description of small mammals study place and capture methodology with traps. It provides basic characteristics of Neries regional park and Šeškinės oz. Describes various small rodents and insectivores in mammalian morphological characterization, the essential features of the biology. Conducted small mammal trapping results analysis in different habitats in 2010 and 2011. There were detected 3 species of insectivorous mammals in 2010 and 2011 (simple shrew, dwarf shrew and water shrew). And there were detected 8 species of rodents (brown vole, simple vole, meadow vole, swamp vole, creeping mouse, yellow-neck mouse, little girl mouse and grey rat) int the same warm season. An analysis of 2010 - 2011 years of data Dūkštas oak and Šeškinės oz different habitats observed in small mammal diversity and abundance increase in late summer, especially in September. In September, the diversity and abundance data were the highest. Dominant species in different habitats were brown vole in Dūkštas oak and Šeškinės oz. He was caught in the catch a maximum of small rodents and insectivorous mammals.
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Strategic management of artificial watering points for biodiversity conservationMontague-Drake, Rebecca, School of Biological, Earth & Environmental Sciences, UNSW January 2004 (has links)
Since pastoralism began in Australia???s rangelands, the number of artificial watering points (AWPs) has increased dramatically, such that today, few areas of rangeland are further than 10 km from water. This increased availability of water has caused many ecological impacts. Unfortunately, such impacts are poorly understood in the context of an Australian conservation reserve, thus hindering strategic management. This study examined the spatial distribution of vertebrate (kangaroos, small mammals, lizards and avifauna) and vegetative variables around open AWPs as well as AWPs that have been closed since pastoralism (sheep-grazing) ceased nearly thirty years ago in Sturt National Park, arid New South Wales. The study also examined vertebrate use of AWPs, with a particular emphasis on kangaroos and avifauna. The study revealed that most variables showed few differences in spatial distribution with distance from open and closed AWPs, thus suggesting that the observed piospheric impacts were primarily attributable to historical sheep-grazing. Indeed, piospheric patterns were weak suggesting some recovery over the last thirty years. That kangaroos did not exhibit water-focused grazing is no surprise, since despite their regular use of AWPs, particularly during hot, dry times, the current spatial arrangement of AWPs facilitates regular travel to, and from, such resources allowing kangaroos, like much other fauna, to distribute themselves in relation to food and shelter preferences rather than in relation to water supply. In contrast, the majority of avifaunal groups (excluding ground-dwelling species) were clustered around open AWPs, often irrespective of season, because of food and water requirements. Such spatial concentrations of avifauna are thought to cause a range of interspecific effects. Experimental AWP closure and GIS modelling showed that whilst closure of AWPs will increase the average distance to water, which will have key benefits, the majority of areas in Sturt National Park would still be accessible to most water-dependent species even if all unused AWPs were closed. Strategic retention of AWPs to replace water sources lost since European settlement, aid threatened and migratory species??? conservation and enhance nature-based tourism opportunities is thus recommended and an example of a strategic management and monitoring plan outlined.
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Discriminando múltiplos fatores determinantes da partição de nicho em pequenos mamíferos sul-americanosGonçalves, Larissa Oliveira January 2013 (has links)
A estruturação em comunidades biológicas sugere que há fatores que determinam quais espécies poderão ocorrer juntas. Os pequenos mamíferos sul-americanos (marsupiais e roedores cricetídeos) apresentam um padrão de dispersão no continente sul-americano bastante distinto. Os marsupiais chegaram ao continente há cerca de 100 milhões de anos e os roedores cricetídeos o colonizaram apenas na formação do Istmo do Panamá em aproximadamente 2,5 milhões de anos. Atualmente esses dois grupos ocupam nichos bastante diversos e também específicos. O objetivo geral desta dissertação é explorar padrões funcionais entre pequenos mamíferos sul-americanos, apresentando uma nova métrica de análise e discriminando os principais mecanismos que estruturam esses padrões. Assim, ela está dividida em dois capítulos: o primeiro apresenta uma nova abordagem analítica para o cálculo de divergência funcional entre clados coocorrentes na mesma comunidade; o segundo trata de avaliar os principais determinantes da divergência funcional entre marsupiais e roedores cricetídeos sul-americanos. A métrica desenvolvida no primeiro capítulo foi adaptada da abordagem de diversidade beta funcional, entretanto, ao invés de compararmos pares de comunidades, comparamos pares de clados que coocorrem na mesma comunidade, distinguindo o quanto similiar ou diferente funcionalmente esses clados são. No segundo capítulo, verificamos que fatores ambientais, funcionais, históricos e evolutivos influenciam a divergência funcional entre os dois clados aqui estudados. Além disso, nós encontramos uma tendência de aumento da diferenciação de nicho entre marsupiais e roedores cricetídeos em direção ao norte do continente sul-americano. Nós podemos inferir que a porta de entrada da colonização dos roedores cricetídeos no continente determina, ainda hoje, padrões de funcionalidade dos ambientes, além de outros fatores importantes como o clima. / The existence of structure in biological communities suggests that there are factors that determine which species may occur together. Small mammals of South America (marsupials and cricetid rodents) show a pattern of dispersal in this continent quite different and interesting. Marsupials arrived on South American continent about 100 million years and cricetid rodents only colonized it in the formation of the Isthmus of Panama, approximately 2.5 million years. Currently, these two groups occupy several and specific niches. The major goal of this thesis is to explore functional patterns among small mammals in South America, presenting an analytical novelty and discriminating mechanisms that driving these patterns. Thus it is divided into two chapters: the first presents a new functional approach for the calculation of functional divergence among clades co-occurring in the same community; the second evaluates the main drivers of functional divergence between marsupials and cricetid rodents in South America. The metric developed in the first chapter was adapted from the approach of functional beta diversity, however, instead of comparing pairs of communities, we compared pairs of clades co-occurring in the same community, discriminating how functionally similar or different these clades are. In the second chapter, we found that environmental, functional, evolutionary and historical factors determine the functional divergence among two clades studied here. Furthermore, we found a trend of increased niche differentiation between marsupials and cricetid rodents northward South American continent. We may infer that the gateway of cricetid rodents already determines patterns of functionality in environments nowadays, beyond other important factors, like climate.
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STATUS AND DISTRIBUTION OF THE STATE-THREATENED MARSH RICE RAT (ORYZOMYS PALUSTRIS) IN ILLINOISEubanks, Bryan Wayne 01 May 2010 (has links)
The marsh rice rat (Oryzomys palustris) is a semi-aquatic rodent classified as state-threatened in Illinois due to historical wetland loss coupled with being on the northern periphery of its range. The most recent survey for this species in Illinois occurred in 1988, and this study reassessed its status and distribution. From 2007 to 2009, I used live traps to sample for rice rats at previously occupied and random wetland-dominated sites in 5 southern Illinois watersheds. I captured 132 individual rice rats 192 times in 13,248 trap nights. Capture success was 15.10 captures/1,000 trap nights. I detected rice rats within 3 of 5 watersheds, 16 of 48 sites, and 5 new locations. Most rice rats were captured in permanent or semi-permanent emergent wetlands and rice rat occurrence was strongly related with coal mine-associated wetlands. I collected microhabitat measurements at 10% of trap locations and recorded landcover types within and around sites. I analyzed data using t-tests, logistic regression, and occupancy modeling. Percent herbaceous cover and percent visual obstruction (0.0-0.5m) positively influenced rice rat occurrence and were among the most important microhabitat models. The best model in the candidate set of landcover variables included proportion of upland grass in areas surrounding wetlands as a predictor of rice rat occurrence. I believe insufficient evidence exists to warrant removal of the threatened status of the marsh rice rat. However, current management practices, such as wetland restoration, grassland restoration, and mowing of roadside ditches, likely benefit rice rat populations. Slight modification of these management activities may facilitate the eventual delisting of marsh rice rats.
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Discriminando múltiplos fatores determinantes da partição de nicho em pequenos mamíferos sul-americanosGonçalves, Larissa Oliveira January 2013 (has links)
A estruturação em comunidades biológicas sugere que há fatores que determinam quais espécies poderão ocorrer juntas. Os pequenos mamíferos sul-americanos (marsupiais e roedores cricetídeos) apresentam um padrão de dispersão no continente sul-americano bastante distinto. Os marsupiais chegaram ao continente há cerca de 100 milhões de anos e os roedores cricetídeos o colonizaram apenas na formação do Istmo do Panamá em aproximadamente 2,5 milhões de anos. Atualmente esses dois grupos ocupam nichos bastante diversos e também específicos. O objetivo geral desta dissertação é explorar padrões funcionais entre pequenos mamíferos sul-americanos, apresentando uma nova métrica de análise e discriminando os principais mecanismos que estruturam esses padrões. Assim, ela está dividida em dois capítulos: o primeiro apresenta uma nova abordagem analítica para o cálculo de divergência funcional entre clados coocorrentes na mesma comunidade; o segundo trata de avaliar os principais determinantes da divergência funcional entre marsupiais e roedores cricetídeos sul-americanos. A métrica desenvolvida no primeiro capítulo foi adaptada da abordagem de diversidade beta funcional, entretanto, ao invés de compararmos pares de comunidades, comparamos pares de clados que coocorrem na mesma comunidade, distinguindo o quanto similiar ou diferente funcionalmente esses clados são. No segundo capítulo, verificamos que fatores ambientais, funcionais, históricos e evolutivos influenciam a divergência funcional entre os dois clados aqui estudados. Além disso, nós encontramos uma tendência de aumento da diferenciação de nicho entre marsupiais e roedores cricetídeos em direção ao norte do continente sul-americano. Nós podemos inferir que a porta de entrada da colonização dos roedores cricetídeos no continente determina, ainda hoje, padrões de funcionalidade dos ambientes, além de outros fatores importantes como o clima. / The existence of structure in biological communities suggests that there are factors that determine which species may occur together. Small mammals of South America (marsupials and cricetid rodents) show a pattern of dispersal in this continent quite different and interesting. Marsupials arrived on South American continent about 100 million years and cricetid rodents only colonized it in the formation of the Isthmus of Panama, approximately 2.5 million years. Currently, these two groups occupy several and specific niches. The major goal of this thesis is to explore functional patterns among small mammals in South America, presenting an analytical novelty and discriminating mechanisms that driving these patterns. Thus it is divided into two chapters: the first presents a new functional approach for the calculation of functional divergence among clades co-occurring in the same community; the second evaluates the main drivers of functional divergence between marsupials and cricetid rodents in South America. The metric developed in the first chapter was adapted from the approach of functional beta diversity, however, instead of comparing pairs of communities, we compared pairs of clades co-occurring in the same community, discriminating how functionally similar or different these clades are. In the second chapter, we found that environmental, functional, evolutionary and historical factors determine the functional divergence among two clades studied here. Furthermore, we found a trend of increased niche differentiation between marsupials and cricetid rodents northward South American continent. We may infer that the gateway of cricetid rodents already determines patterns of functionality in environments nowadays, beyond other important factors, like climate.
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Vliv způsobu a stáří rekultivace ploch po povrchové těžbě na biodiverzitu drobných zemních savců / The influence of the type and age of post-mining areas restoration on biodiversity of small terrestrial mammals.MIKLAS, Bořek January 2011 (has links)
The aim of the study was to compare different types and ages of restoration from the small mammal biodiversity perspective. In 2004, three linear and two quadratic trappings of small terrestrial mammals were performed at the Velká podkrušnohorská spoil heap. Linear trappings were repeated in 2009 and quadratic were repeated in 2010. In 2004, 174 small mammals in the linear trappings and 199 small mammals in the quadratic trappings were captured. We found, that the wetland localities were the richest in small mammal diversity, the forestry restored areas were second ones, and the agriculturally restored areas were the poorest ones. During the repeated trappings, 45 small mammals in linear trappings and 64 small mammals in quadratic trappings were captured. A decrease of both abundance and biodiversity was recorded in the both types of trappings. The highest biodiversity was on wetland and forestry restored areas. The lowest biodiversity was on agriculturally restored areas. The highest abundance was on forestry sites during the linear trappings. The wetland areas were second ones and the lowest abundance was on agriculturally restored areas. Value of abundance in quadratic trappings was almost the same in wetland and forest habitats, whilst the abundance of agricultural areas was significantly lower. The results show the importance of wetland habitats, which are very important part of restoration and have a positive impact on the overall biodiversity in the landscape.
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The Effects of Artificial Water Sources on Small Mammal CommunitiesJanuary 2013 (has links)
abstract: Modified and artificial water sources can be used as a management tool for game and non-game wildlife species. State, federal, and private agencies allocate significant resources to install and maintain artificial water sources (AWS) annually. Capture mark recapture methods were used to sample small mammal communities in the vicinity of five AWS and five paired control sites (treatments) in the surrounding Sonoran desert from October 2011 to May 2012. I measured plant species richness, density, and percent cover in the spring of 2012. A Multi-response Permutation Procedure was used to identify differences in small mammal community abundance, biomass, and species richness by season and treatment. I used Principle Component Analysis to reduce 11 habitat characteristics to five habitat factors. I related rodent occurrence to habitat characteristics using multiple and logistic regression. A total of 370 individual mammals representing three genera and eight species of rodents were captured across 4800 trap nights. Desert pocket mouse (Chaetodipus penicillatus) was the most common species in both seasons and treatments. Whereas rodent community abundance, biomass, and richness were similar between seasons, community variables of AWS were greater than CS. Rodent diversity was similar between treatments. Desert pocket mouse abundance and biomass were twice as high at AWS when compared to controls. Biomass of white-throated woodrat (Neotoma albigula) was five times greater at AWS. Habitat characteristics were similar between treatments. Neither presence of water nor distance to water explained substantial habitat variation. Occurrence of rodent species was associated with habitat characteristics. Desert rodent communities are adapted for arid environments (i.e. Heteromyids) and are not dependent on "free water". Higher abundances of desert pocket mouse at AWS were most likely related to increased disturbance and debris and not the presence of water. The results of this study and previous studies suggest that more investigation is needed and that short term studies may not be able to detect interactions (if any) between AWS and desert small mammal communities. / Dissertation/Thesis / M.S. Applied Biological Sciences 2013
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Importância dos corredores ripários para a fauna - pequenos mamíferos em manchas de floresta, matriz do entorno e elementos lineares em uma paisagem fragmentada de Mata Atlântica / Importance of riparian corridors for the fauna: small mammals in forest patches, surrounding matrix and linear elements in an Atlantic forest fragmented landscapeLaura Regina Capelari Naxara 20 October 2008 (has links)
Essa dissertação de mestrado objetivou avaliar a importância dos corredores ripários para a fauna em uma paisagem fragmentada de Mata Atlântica. Em quatro sistemas compostos por fragmento - corredor fragmento avaliamos tanto a assembléia de pequenos mamíferos (capitulo 2) como a qualidade do habitat através da estrutura da vegetação e da disponibilidade de recurso alimentar para a fauna (capitulo 3). No capitulo 2 comparamos a assembléia de pequenos mamíferos entre áreas abertas do entorno, corredores ripários, bordas e interiores de fragmentos. Verificou-se uma forte segregação na distribuição das espécies entre áreas abertas da matriz e os habitats florestados. Todas as espécies endêmicas só foram capturadas nos habitats florestais, enquanto que a matriz de áreas abertas abrigou uma assembléia de pequenos mamíferos composta exclusivamente por espécies não endêmicas ao bioma Mata Atlântica e apenas duas espécies não-endêmicas ocuparam todos os habitats. Observou-se ainda, que as flutuações temporais na abundância das espécies não diferiram entre habitats, ou seja, as diferenças que encontramos na distribuição das espécies não dependeram da sessão de captura. Além disso, a riqueza e abundância das espécies endêmicas foram maiores nos ambientes florestais em comparação a matriz aberta, enquanto que a abundância das espécies não-endêmicas foi maior na matriz comparada aos interiores de fragmentos. As duas espécies endêmicas mais abundantes na área de estudo ocorreram apenas nos habitats florestais, e a abundância das duas foi menor nas bordas do que nos interiores e, em um caso, também do que nos corredores. Por outro lado, a abundância de uma das três espécies não-endêmicas mais comuns foi maior nas bordas do que nos interiores. Assim concluímos os corredores ripários funcionam como elemento conector para a fauna endêmica de pequenos mamíferos da Mata Atlântica, amenizando os efeitos deletérios da fragmentação. No capitulo 3, ao avaliar a qualidade do habitat entre os corredores ripários, e bordas e interiores de fragmentos secundários, observamos que a oferta de recursos alimentares (artrópodes e frutos) para a fauna, assim como a estrutura da vegetação, em termos da estratificação da densidade da folhagem, não variou entre os diferentes tipos de habitat florestal. Nesse sentido, nossos resultados sugerem que, ao contrário do observado em florestas tropicais primárias, em florestas tropicais secundárias não há um efeito de borda claro sobre a qualidade do habitat em termos de estrutura da vegetação ou disponibilidade de alimento para a fauna nem mesmo em estruturas lineares como os corredores. Os resultados apresentados nos dois capítulos evidenciam a importância da manutenção dos corredores ripários para a conservação, em paisagens fragmentadas de Mata Atlântica, da fauna de um dos grupos mais diversificados de mamíferos. / This master thesis aimed to evaluate the importance of riparian corridors for the fauna in an Atlantic Forest fragmented landscape. In four systems composed by fragment corridor fragment, we evaluate both the small mammal assemblage (chapter 2) and the habitat quality measured through the vegetation structure and food resources availability for the fauna (chapter 3). In chapter 2 we compared small mammal assemblages among open areas of the surrounding matrix, riparian corridors, edges and interiors of forest fragments. We verified a strong segregation in species distribution between the open matrix and the forested habitats. Endemic species were captured only in forested habitats, while the open areas of the matrix harbored a small mammals assemblage composed exclusively by species non-endemic to the Atlantic Forest biome, and only two non-endemic species occupied all habitat types. We also observed that temporal fluctuations in species abundance did not differ among habitats, that is, observed differences in species distribution were not dependent on capture session. Moreover, richness and abundance of endemic species were higher in forested habitats than in the open areas of matrix, while the abundance of nonendemic species was higher in the matrix than in the interior of forest fragments. The two most abundant endemic species occurred only in forested habitats and their abundance was lower at edges compared to forest interiors and, for one of them, also compared to riparian corridors. On the other hand, the abundance of one of the three most common non-endemic species was higher at edges than in interiors. We conclude that riparian corridors function as a connector element for the endemic small mammals of the Atlantic Forest, minimizing the deleterious effects of habitat fragmentation. In chapter 3, through the evaluation of habitat quality in riparian corridors, edges and interiors of second-growth fragments, we observed that food resource availability (arthropods and fruits) for the fauna, as well as the vegetation structure, measured as foliage vertical stratification, did not differ among the three forested habitats. Thus, our results suggest that, contrary to the observed in primary tropical forests, there is no clear edge effects on vegetation structure or on food resources availability for the fauna in secondary forest fragments even in linear habitats such as corridors. The results reported in these two chapters highlight the importance of the maintenance of riparian corridors for the conservation, in fragmented landscapes of the Atlantic Forest, of one of the most diverse group of mammals.
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Discriminando múltiplos fatores determinantes da partição de nicho em pequenos mamíferos sul-americanosGonçalves, Larissa Oliveira January 2013 (has links)
A estruturação em comunidades biológicas sugere que há fatores que determinam quais espécies poderão ocorrer juntas. Os pequenos mamíferos sul-americanos (marsupiais e roedores cricetídeos) apresentam um padrão de dispersão no continente sul-americano bastante distinto. Os marsupiais chegaram ao continente há cerca de 100 milhões de anos e os roedores cricetídeos o colonizaram apenas na formação do Istmo do Panamá em aproximadamente 2,5 milhões de anos. Atualmente esses dois grupos ocupam nichos bastante diversos e também específicos. O objetivo geral desta dissertação é explorar padrões funcionais entre pequenos mamíferos sul-americanos, apresentando uma nova métrica de análise e discriminando os principais mecanismos que estruturam esses padrões. Assim, ela está dividida em dois capítulos: o primeiro apresenta uma nova abordagem analítica para o cálculo de divergência funcional entre clados coocorrentes na mesma comunidade; o segundo trata de avaliar os principais determinantes da divergência funcional entre marsupiais e roedores cricetídeos sul-americanos. A métrica desenvolvida no primeiro capítulo foi adaptada da abordagem de diversidade beta funcional, entretanto, ao invés de compararmos pares de comunidades, comparamos pares de clados que coocorrem na mesma comunidade, distinguindo o quanto similiar ou diferente funcionalmente esses clados são. No segundo capítulo, verificamos que fatores ambientais, funcionais, históricos e evolutivos influenciam a divergência funcional entre os dois clados aqui estudados. Além disso, nós encontramos uma tendência de aumento da diferenciação de nicho entre marsupiais e roedores cricetídeos em direção ao norte do continente sul-americano. Nós podemos inferir que a porta de entrada da colonização dos roedores cricetídeos no continente determina, ainda hoje, padrões de funcionalidade dos ambientes, além de outros fatores importantes como o clima. / The existence of structure in biological communities suggests that there are factors that determine which species may occur together. Small mammals of South America (marsupials and cricetid rodents) show a pattern of dispersal in this continent quite different and interesting. Marsupials arrived on South American continent about 100 million years and cricetid rodents only colonized it in the formation of the Isthmus of Panama, approximately 2.5 million years. Currently, these two groups occupy several and specific niches. The major goal of this thesis is to explore functional patterns among small mammals in South America, presenting an analytical novelty and discriminating mechanisms that driving these patterns. Thus it is divided into two chapters: the first presents a new functional approach for the calculation of functional divergence among clades co-occurring in the same community; the second evaluates the main drivers of functional divergence between marsupials and cricetid rodents in South America. The metric developed in the first chapter was adapted from the approach of functional beta diversity, however, instead of comparing pairs of communities, we compared pairs of clades co-occurring in the same community, discriminating how functionally similar or different these clades are. In the second chapter, we found that environmental, functional, evolutionary and historical factors determine the functional divergence among two clades studied here. Furthermore, we found a trend of increased niche differentiation between marsupials and cricetid rodents northward South American continent. We may infer that the gateway of cricetid rodents already determines patterns of functionality in environments nowadays, beyond other important factors, like climate.
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