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Bird responses to habitat fragmentation at different spatial scales : illustrations from Madagascan and Australian case studiesWatson, James Edward Maxwell January 2004 (has links)
Despite increasing publicity, habitat loss and fragmentation remain a serious threat to biodiversity. The main objectives of this research were (i) to study the effects of forest fragmentation on the distribution and abundance of resident birds in the fragmented littoral forests of southeastern Madagascar and temperate woodlands of southeastern Australia at three spatial scales (patch, landscape and regional) and (ii) to place the results of these case studies within the realms of the equilibrium theory of island biogeography and its descendent theories, to ascertain whether it is appropriate to use these theories to derive conservation scenarios within these threatened regions. Deforestation of Madagascar's remaining forests is considered a global concern due to both its current high intensity and the small amount of forest claimed to be remaining on the island. Surprisingly, very few studies have considered the impacts of forest fragmentation on bird diversity in Madagascar. A multi-scale study on the effects of littoral forest fragmentation and degradation on birds is therefore a major step forward for bird conservation on the island. Furthermore, prior to this study no known work has been conducted on the avifauna within the threatened littoral forests of eastern Madagascar. My results indicated that (i) the littoral forests contained bird species assemblages that were unique when compared to neighbouring forest habitats, (ii) many forest-dependent bird species were significantly affected by habitat structure and especially proximity to forest edge and (iii) many forest-dependent species were affected by landscape factors such as remnant shape and remnant size. No relationship was found between measures of landscape composition, remnant 'isolation' and bird distribution within littoral forest remnants.
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Temporal and spatial variability in onshore cod (Gadus morthua) migrations : associations with atmosphere-ocean dynamics and capelin (Mallotus villosus) distributionsRose, George A. January 1988 (has links)
I studied the onshore migrations of Atlantic cod (Gadus morhua) in the northern Gulf of St. Lawrence to test the predictability of the distributions and catches of a migratory predatory fish relative to physical oceanographic processes and the distributions and abundances of its prey. To survey daily fish distributions and abundances by species, hydroacoustic signal discriminant methods were developed which classified schools of cod, capelin (Mallotus villosus), and mackerel (Scomber scombrus) with 93% success. Physical oceanographic processes along the 150 km of coastline studied were characterized by Ekman-type upwellings and downwellings forced by alongshore winds at periods $>$3 d. Physical elements of this system (principally currents and temperature) were associated with cross-shore movements of cod and accounted for as much as 83% of the variance in mean trap catch. Cod and capelin formed coherent spatial distributions when capelin were congregated where sea temperatures were most favorable to cod (1 to 5$ sp circ$C) and mean capelin densities were above 100/10$ sp5$m$ sp3$. Coherences were in phase at larger scales ($>$10 km) but became increasingly out of phase at smaller scales. Cod distributions fit the predictions of an "ideal" distribution (allometric constant = 0.67) when two constraints were put on the relationship: (1) capelin densities above 100/10$ sp5$m$ sp3$, and (2) temperatures between 1 and 9$ sp circ$C.
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Diel Changes in the Vertical Distributions of Some Common Fish Larvae in Southern Kaneohe Bay, Oahu, HawaiiWatson, William 12 1900 (has links)
Nine series of vertically-stratified zooplankton tows were made
with a closing net at a single station in southern Kaneohe Bay, Oahu,
Hawaii, between 31 August 1973 and 11 April 1974. Sampling periods
occupied from 12 to 26 hours, with tows usually taken at about 3 m
intervals between the surface and a maximum depth of 10 m.
A total of 21,254 fish larvae of 49 kinds was collected. Six
species were abundant: Foa brachygrammus, Omobranchus elongatus,
Callionymus decoratus, Caranx mate, Stolephorus purpureus, and
Abudefduf abdominalis. Blennius sp. and Gnathanodon speciosus were
commonly taken in small numbers.
These common larvae displayed five "distribution patterns:
1. F. brachygrammus and the smallest S. purpureus were most
abundant near the surface at night and at depths below 4 m
during the day;
2. C. mate and G. speciosus were dispersed throughout the water
column at night and usually most abundant between 5 m and 6 m
depth during the day;
3. Blennius sp., o. elongatus, and A. abdominalis were dispersed
throughout the water column at night and concentrated near
the surface during the day;
4. the larger ~. purpureus maintained a level of maximum abundance
below 6 m day and night;
5. C. decoratus was taken at all depths at all times.
Patterns 1, 2, and 3 are shown to be light-related. Pattern 4 is
shown to be partially attributable to avoidance of the towed net by
S. purpureus larvae larger than about 6mm, and a feeding-related
migration is proposed to account for pattern 5.
The observed patterns are analogous to those shown for fish larvae
in the open ocean on scales of from 50 m to 200 m. It is proposed that
Kaneohe Bay represents a vertically compressed ocean with respect to
the vertical distribution of fish larvae. / Typescript. Bibliography: leaves 130-134.
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Phylogeography of the kelp genus Durvillaea (Phaeophyceae: Fucales)Fraser, Ceridwen, n/a January 2009 (has links)
Durvillaea, a kelp genus occurring only in the Southern Hemisphere, presents an ideal system for studies of marine connectivity and postglacial recolonisation. Durvillaea contains five currently-recognised species, four of which are non-buoyant. Whereas all non-buoyant species are restricted to the south-western Pacific, the sole buoyant species (D. antarctica) has a far wider, circumpolar distribution, strongly suggesting that long-distance dispersal in D. antarctica is achieved by rafting. This contrast in predicted dispersal ability among Durvillaea species provides an opportunity for natural phylogeographic comparisons, thereby assessing the effectiveness of rafting as a long-distance dispersal mechanism. Additionally, the inability of D. antarctica to survive in ice-affected areas, combined with its broad distribution, make it an ideal candidate for studies of postglacial recolonisation.
Phylogenetic and biogeographic relationships within Durvillaea were here assessed using sequence data from mitochondrial (COI), chloroplast (rbcL) and nuclear (18S) DNA. Genetic data were obtained from more than 500 specimens, including representatives from across the geographic range of each recognised species of Durvillaea. Mitochondrial data for Durvillaea were found to be highly phylogenetically informative, with 117 variable sites observed over a 629 bp fragment of COI. Chloroplast and nuclear markers, on the other hand, showed less variation than COI, but nonetheless contributed useful phylogenetic information. Phylogenetic analyses were performed using both Maximum Likelihood and Bayesian approaches.
Contrasting patterns of genetic diversity were observed across the range of D. potatorum in Australia, with genetic homogeneity throughout western sites versus relatively high levels of diversity in eastern populations. Based on these results, I hypothesise that D. potatorum recolonised much of the western part of its range postglacially, perhaps being entirely eliminated from western Tasmania during the last glacial period by altered oceanographic systems. Additionally, 'western' and 'eastern' D. potatorum haplotypes formed deeply-divergent clades, likely reflecting geographic isolation on either side of the Bassian Isthmus during Pleistocene marine regressions.
Substantial genetic diversity was observed across the range of the circumpolar species D. antarctica. Within New Zealand, phylogenetic and morphological analyses of D. antarctica indicate that two morphotypes ('cape' and 'thonged' forms) likely represent reproductively isolated species, with the 'cape' lineage apparently restricted to southern New Zealand. Whereas the 'cape' lineage showed little genetic variation throughout its range, the 'thonged' lineage exhibited marked phylogeographic structure, with high genetic diversity and a clear north - south genetic disjunction delineated by the Canterbury Bight.
On a broader, circumpolar scale, D. antarctica showed contrasting patterns of genetic diversity, with high levels of variation in low-latitude regions (e.g., continental coasts of New Zealand and Chile), versus near-homogeneity at high, subantarctic latitudes. These phylogeographic contrasts strongly suggest that D. antarctica recolonised much of the subantarctic region only recently, most plausibly following extirpation by ice scour at the Last Glacial Maximum (LGM). Locations of putative recolonised islands relative to 'refugial' areas indicate that Antarctic sea ice was likely more extensive at the LGM than previous studies have suggested.
Latitudinal contrasts in genetic diversity were also observed among Chilean populations of D. antarctica, with a single mitochondrial haplotype detected throughout Chilean Patagonia versus high diversity in central Chile (32�-42�S). The Patagonian populations appear to have recolonised the region postglacially, following recession of the Patagonian Ice Sheet after the LGM. These populations show transoceanic ancestry, with a closer relationship to populations in the subantarctic and southern New Zealand regions than to those in central Chile. Substantial phylogeographic structure was evident across small spatial scales in central Chile, and the correspondence of major genetic disjunctions among central Chilean sites with the presence of long stretches of unsuitable substrate (beaches) strongly suggests that habitat discontinuity drives genetic isolation in this dispersive species.
Broad-scale molecular phylogenetic analyses indicate that the current taxonomy of Durvillaea species requires substantial revision. Previously-recognised 'morphotypes' of Durvillaea (of D. potatorum in Australia, and D. antarctica in New Zealand), for example, were here found to be genetically distinct, likely representing reproductively-isolated species.
This phylogeographic research on Durvillaea kelp sheds new light on the historical impacts of climate change on Southern Hemisphere marine environments, and on the processes driving evolution in a marine macroalga.
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Phylogeography of the kelp genus Durvillaea (Phaeophyceae: Fucales)Fraser, Ceridwen, n/a January 2009 (has links)
Durvillaea, a kelp genus occurring only in the Southern Hemisphere, presents an ideal system for studies of marine connectivity and postglacial recolonisation. Durvillaea contains five currently-recognised species, four of which are non-buoyant. Whereas all non-buoyant species are restricted to the south-western Pacific, the sole buoyant species (D. antarctica) has a far wider, circumpolar distribution, strongly suggesting that long-distance dispersal in D. antarctica is achieved by rafting. This contrast in predicted dispersal ability among Durvillaea species provides an opportunity for natural phylogeographic comparisons, thereby assessing the effectiveness of rafting as a long-distance dispersal mechanism. Additionally, the inability of D. antarctica to survive in ice-affected areas, combined with its broad distribution, make it an ideal candidate for studies of postglacial recolonisation.
Phylogenetic and biogeographic relationships within Durvillaea were here assessed using sequence data from mitochondrial (COI), chloroplast (rbcL) and nuclear (18S) DNA. Genetic data were obtained from more than 500 specimens, including representatives from across the geographic range of each recognised species of Durvillaea. Mitochondrial data for Durvillaea were found to be highly phylogenetically informative, with 117 variable sites observed over a 629 bp fragment of COI. Chloroplast and nuclear markers, on the other hand, showed less variation than COI, but nonetheless contributed useful phylogenetic information. Phylogenetic analyses were performed using both Maximum Likelihood and Bayesian approaches.
Contrasting patterns of genetic diversity were observed across the range of D. potatorum in Australia, with genetic homogeneity throughout western sites versus relatively high levels of diversity in eastern populations. Based on these results, I hypothesise that D. potatorum recolonised much of the western part of its range postglacially, perhaps being entirely eliminated from western Tasmania during the last glacial period by altered oceanographic systems. Additionally, 'western' and 'eastern' D. potatorum haplotypes formed deeply-divergent clades, likely reflecting geographic isolation on either side of the Bassian Isthmus during Pleistocene marine regressions.
Substantial genetic diversity was observed across the range of the circumpolar species D. antarctica. Within New Zealand, phylogenetic and morphological analyses of D. antarctica indicate that two morphotypes ('cape' and 'thonged' forms) likely represent reproductively isolated species, with the 'cape' lineage apparently restricted to southern New Zealand. Whereas the 'cape' lineage showed little genetic variation throughout its range, the 'thonged' lineage exhibited marked phylogeographic structure, with high genetic diversity and a clear north - south genetic disjunction delineated by the Canterbury Bight.
On a broader, circumpolar scale, D. antarctica showed contrasting patterns of genetic diversity, with high levels of variation in low-latitude regions (e.g., continental coasts of New Zealand and Chile), versus near-homogeneity at high, subantarctic latitudes. These phylogeographic contrasts strongly suggest that D. antarctica recolonised much of the subantarctic region only recently, most plausibly following extirpation by ice scour at the Last Glacial Maximum (LGM). Locations of putative recolonised islands relative to 'refugial' areas indicate that Antarctic sea ice was likely more extensive at the LGM than previous studies have suggested.
Latitudinal contrasts in genetic diversity were also observed among Chilean populations of D. antarctica, with a single mitochondrial haplotype detected throughout Chilean Patagonia versus high diversity in central Chile (32�-42�S). The Patagonian populations appear to have recolonised the region postglacially, following recession of the Patagonian Ice Sheet after the LGM. These populations show transoceanic ancestry, with a closer relationship to populations in the subantarctic and southern New Zealand regions than to those in central Chile. Substantial phylogeographic structure was evident across small spatial scales in central Chile, and the correspondence of major genetic disjunctions among central Chilean sites with the presence of long stretches of unsuitable substrate (beaches) strongly suggests that habitat discontinuity drives genetic isolation in this dispersive species.
Broad-scale molecular phylogenetic analyses indicate that the current taxonomy of Durvillaea species requires substantial revision. Previously-recognised 'morphotypes' of Durvillaea (of D. potatorum in Australia, and D. antarctica in New Zealand), for example, were here found to be genetically distinct, likely representing reproductively-isolated species.
This phylogeographic research on Durvillaea kelp sheds new light on the historical impacts of climate change on Southern Hemisphere marine environments, and on the processes driving evolution in a marine macroalga.
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The taxonomy and distribution of Australian terrestrial tardigradesClaxton, Sandra Kaye January 2004 (has links)
Thesis (PhD)--Macquarie University, Division of Environmental & Life Sciences, Dept. of Biological Sciences, 2004. / Bibliography: p. 599-618 (pt. 1). / Introduction -- Materials and methods -- Taxonomic studies -- Species descriptions and keys to genera and species -- Tardigrades from cryptograms and leaf litter on soil and from a sand island -- The distribution of terrestrial tardigrades in eastern Australia. / The terrestrial tardigrade fauna of Australia has been given scant attention in the past. This study was undertaken to collect and identify terrestrial tardigrade species from a wide a variety of habitats in Australia. This new taxonomic data set was then used to explore zoogeographic patterns and processes in eastern Australia. -- The first part of this study is concerned with the clarification of some taxonomic problems which arose during the course of the study, the solution of which was essential in order to delineate species boundaries. In the family Macrobiotidae, two genera, Minibiotus and Calcarobiotus, are remarkable for the high number of species recorded in Australia relative to other parts of the world. Within the genus Macrobiotus many new species within two groups, hufelandi and harmsworthi, are described and it is concluded that the nominal species in each case is not part of the Australian fauna. A new genus, Haptobiotus, is described in the family Macrobiotidae. -- In order to clarify species within the Diphascon (D.) pingue group, populations were subjected to multivariate analysis. The analysis resulted in the conclusion that only two species in that group, D. pingue and D. pinguiforme, have so far been found in Australia. The study also resulted in the synonymisation with D. pingue and D. pinguiforme of two previously described species from Australia. -- The discovery of a new genus, Milnesioides, provides an insight into the structure and function of the buccal apparatus of the rare monotypic genus Limmenius within the family Milnesiidae. A new genus. Lexia, is described in the subfamily Itaquasconinae along with other members of this group which has been under-recorded in Australia. The descriptions of three species in the genus Antechiniscus provides new morphological detail for this genus and provides additional evidence that the genus is found only in cool temperate regions in the southern hemisphere. -- The 161 species in 34 genera found in this study are described and line drawings provided. Of the 161 species, 59 are new to science and a further 16 have been published as new species during the course of the project. Also included are descriptions of an additional 21 species, recorded from Australia by other authors but not found in this study. Eleven of these species are probably misidentified. Keys to genera and species are supplied. -- A small but revealing study provides some preliminary data on tardigrade species associated with cryptogams or leaf litter on soil and sand. The detection of a rich fauna suggests that such habitats need to be examined if the full tardigrade fauna of Australia is to be documented. -- Data from 36 sites in eastern Australia containing 141 species were subjected to multivariate analysis in order to elucidate zoogeographic patterns of tardigrade communities. The study, although preliminary in many ways, showed a high correlation between tardigrade communities and core zoogeographic subregions in eastern Australia, e.g., a northern monsoonal, a nontropical south-eastern and a dry central-western subregion. Two distinct habitat types within the south-eastern subregion, cool temperate rainforest and limestone sites also support distinct species communities. Each tardigrade community consists of cosmopolitan, pantropical, oriental, southern hemisphere and Australian species. The degree to which each of these types contribute to each community is discussed in terms of the evolutionary history and the climatic regime (primarily temperature and length of dry periods) of each subregion and, to a limited extent by passive dispersal. / Mode of access: World Wide Web. / 2 parts (xxvi, 618 leaves (pt. 1), 182 leaves (pt. 2) ill
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Dinâmica da comunidade de Anomura (Crustacea, Decapoda) no litoral paulista : uma análise análise comparativa em dois períodos distintos /Dantas, Daniela Pimenta. January 2012 (has links)
Orientador: Adilson Fransozo / Banca: Antonio Leão Castilho / Banca: Gustavo Monteiro Teixeira / Resumo: O objetivo do presente estudo foi descrever e comparar a comunidade de Anomura estabelecida no substrato não consolidado da Enseada de Ubatuba em um intervalo de sete anos. As coletas foram realizadas na Enseada de Ubatuba, entre os períodos de Julho/98 a Junho/99 (primeiro período) e Julho/06 a Junho/07 (segundo período), com um barco camaroneiro equipado com redes de arrasto double rig. Para a amostragem, foram escolhidos quatro transectos na enseada de Ubatuba: dois paralelos à linha da praia: 10m e 20m de profundidade; e dois próximos à costa: área batida (Exp), ou sujeita á ação de correntes marítimas; e área abrigada (Abr), ou protegida da enseada. Para análise dos fatores ambientais, foram coletadas amostras de água e de sedimento, utilizando-se garrafa de Nansen e pegador de Van Veen, respectivamente. Os organismos foram identificados, mensurados e separados em macho, fêmea e fêmeas ovígeras. Para a comunidade, foram determinados os parâmetros ecológicos: riqueza, diversidade, equidade, dominância e abundância e ocorrência relativa das espécies e da comunidade. Os parâmetros ecológicos foram associados pela correlação de Spearman (p<0,05). A composição da comunidade foi analisada pela análise de similaridade e a associação das espécies com os fatores ambientais foi determinada pela Análise de Correspondência Canônica (ACC) (α=0,1). A matéria orgânica apresentou diferença significativa entre os transectos no segundo período. Nove espécies de anomuros foram obtidas e estiveram distribuídas entre sete gêneros, três famílias e duas superfamílias, representando quase 20% de toda a fauna ao longo da costa de São Paulo. A espécie D. insignis foi as mais abundantes em ambos os períodos. Sua ocorrência na maioria dos meses e transectos permite considerá-la dominante e adaptada a diversas... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Not available / Mestre
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Eco-evolutionary feedback in fish-zooplankton communities on the Scottish island of North UistChitheer, T. January 2018 (has links)
‘Eco-evolutionary feedbacks’ occur when evolution of organismal traits causes environmental change that drives further evolution. Predator and prey interactions provide good examples of eco-evolutionary feedbacks. Here I examine the potential for eco-evolutionary feedbacks between three-spined sticklebacks (Gasterosteus aculeatus, hereafter ‘stickleback’) and their zooplankton prey in lochs (lakes) on the Scottish island of North Uist. Many lochs on the island were colonised by sticklebacks after the last glaciation, approximately 10,000-15,000 years ago. Previous work has shown that sticklebacks in different lochs have diverged greatly from each other in response to local environments. On the other hand, apart from several very old studies on the occurrence of some zooplankton species, there have been no previous in depth studies on the population dynamics of zooplankton on North Uist. I investigated first the diversity and abundance of zooplankton groups and the most common species across all North Uist lochs. Thirty-nine species were classified from three main groups (Rotifera, Cladocera and Copepoda). Species abundance in the presence of fish was relatively more even, while the abundance of zooplankton groups was not generally related to fish presence except for Cladocera in a subset of locations. The effects of predation on the life-history of zooplankton were also examined by comparing reproductive traits of the dominant cladoceran species (Bosmina and Daphnia) in lochs with and without fish. Cladocerans in lochs with fish have more rapid reproductive cycles and higher fecundity parameters, probably in response to the increased threat of predation. These effects remain evident in Bosmina after they have been raised through three generations in the laboratory, supporting the hypothesis that they have a genetic basis and are not a plastic response to predator presence. Life-history variables of cladocerans were also related to abiotic and biotic variation among lochs, including depth, pH, chlorophyll levels and the concentration of alkaline metals. I also demonstrate that stickleback have diversified greatly among lochs in functional trophic traits that determine the efficiency of feeding on different types of prey, which could affect total primary production and the structure of prey communities. Ancestral stickleback populations have adapted according to the type of habitat colonised. Fish feed on benthic prey in shallow lochs, which requires greater effort for successful foraging than that required by fish that feed on planktonic prey. I found that variation in stickleback trophic traits was related to both abiotic and biotic variation among lochs, including loch depth and the mean contributions of planktonic and benthic prey to diet. The results presented in this thesis suggest the possibility of eco-evolutionary feedbacks in these simple ecosystems on North Uist based on the significant responses in fish and zooplankton communities. The thesis also provides a basis for further studies on fish-zooplankton interactions on North Uist and contributes to the wider body of knowledge concerning the relevance of natural variation in shaping the foraging mechanisms of animals.
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Dinâmica da comunidade de Anomura (Crustacea, Decapoda) no litoral paulista: uma análise análise comparativa em dois períodos distintosDantas, Daniela Pimenta [UNESP] 15 February 2012 (has links) (PDF)
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dantas_dp_me_botib.pdf: 1589348 bytes, checksum: c5d0003d06c0b38fbca5512bceeaa8d1 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo do presente estudo foi descrever e comparar a comunidade de Anomura estabelecida no substrato não consolidado da Enseada de Ubatuba em um intervalo de sete anos. As coletas foram realizadas na Enseada de Ubatuba, entre os períodos de Julho/98 a Junho/99 (primeiro período) e Julho/06 a Junho/07 (segundo período), com um barco camaroneiro equipado com redes de arrasto double rig. Para a amostragem, foram escolhidos quatro transectos na enseada de Ubatuba: dois paralelos à linha da praia: 10m e 20m de profundidade; e dois próximos à costa: área batida (Exp), ou sujeita á ação de correntes marítimas; e área abrigada (Abr), ou protegida da enseada. Para análise dos fatores ambientais, foram coletadas amostras de água e de sedimento, utilizando-se garrafa de Nansen e pegador de Van Veen, respectivamente. Os organismos foram identificados, mensurados e separados em macho, fêmea e fêmeas ovígeras. Para a comunidade, foram determinados os parâmetros ecológicos: riqueza, diversidade, equidade, dominância e abundância e ocorrência relativa das espécies e da comunidade. Os parâmetros ecológicos foram associados pela correlação de Spearman (p<0,05). A composição da comunidade foi analisada pela análise de similaridade e a associação das espécies com os fatores ambientais foi determinada pela Análise de Correspondência Canônica (ACC) (α=0,1). A matéria orgânica apresentou diferença significativa entre os transectos no segundo período. Nove espécies de anomuros foram obtidas e estiveram distribuídas entre sete gêneros, três famílias e duas superfamílias, representando quase 20% de toda a fauna ao longo da costa de São Paulo. A espécie D. insignis foi as mais abundantes em ambos os períodos. Sua ocorrência na maioria dos meses e transectos permite considerá-la dominante e adaptada a diversas... / Not available
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Distribuição geográfica de abelhas e plantas associadas através de modelagem computacional / Geographical distribuition of associated bees and plants through computational modelingTereza Cristina Giannini 06 September 2011 (has links)
As abelhas e plantas apresentam diferentes graus de especialização em suas interações. Parceiros mais especialistas frequentemente apresentam uma história evolutiva mútua e sobreposição nas áreas de ocorrência. No entanto, a estrutura espacial dos ambientes nos quais esses grupos se distribuem é caracterizada por padrões complexos e dinâmicos. Para analisar a influência dos fatores que atuam na distribuição de espécies de abelhas e plantas associadas foram utilizadas a modelagem de distribuição de espécies, análise multivariada e ferramentas de sistemas de informações geográficas. Os resultados indicaram que a distribuição de gêneros estritamente associados, como é o caso de Peponapis e Cucúrbita, é influenciada pelo clima das áreas de ocupação, bem como provavelmente, por sua história evolutiva e pela domesticação das abóboras (Cucúrbita). Já os gêneros Krameria e Centris apresentam um padrão mais intrincado de distribuição, uma vez que a interação entre ambos é mais complexa. Centris é um grupo diverso que utiliza recursos florais de outras famílias botânicas além de Krameriaceae, o que provavelmente influencia seus padrões de distribuição. No entanto, os resultados obtidos para Krameria demonstraram de maneira geral, a influência de características climáticas na distribuição do grupo e uma provável dependência maior de Centris em alguns casos. Finalmente, foi também demonstrada a importância da inclusão de dados bióticos no processo da modelagem de distribuição, resultando no aumento da acurácia dos modelos e na alteração da projeção da distribuição para o futuro, considerando-se um cenário de mudança climática. Os resultados foram mais conspícuos quando foram consideradas interações mais estreitas entre espécies de abelhas parasitas e hospedeiras do gênero Bombus, do que entre Centris e Krameria. As técnicas utilizadas, em especial a modelagem de distribuição, representaram uma importante contribuição para a análise efetuada. No entanto, embora crescentemente utilizada, a modelagem de distribuição de espécies demanda técnicas e testes mais robustos para avaliar a acurácia dos modelos gerados. Além disso, um desafio adicional a ser vencido consiste no aumento e melhoria da qualidade dos pontos de ocorrência das espécies, principalmente no Brasil. Faz-se necessário um esforço adicional de coleta, especialmente em algumas áreas específicas, bem como, a conservação e digitalização dos dados das coleções biológicas. Porém, as técnicas utilizadas mostraram um grande potencial a ser explorado em outras análises, envolvendo questões biológicas diferentes, ou outros grupos taxonômicos e camadas de dados. / Bees and plants present different degrees of specialism in their interactions. More specialized partners generally present a mutual evolutionary history and overlap with their occurrence areas. Nevertheless, the spatial structure of environments occupied by them is characterized by complex and dynamic patterns. Species distribution modelling, multivariate analyses and geographical system information tools were used in order to analyze the influence of different factors that act in the geographical distribution of associated bees and plants. Results showed that the geographical distribution of close associated genera, such as Peponapis and Cucúrbita are influenced by the clime of occurrence areas, and also, by their evolutionary history and cucurbits domestication (squashes and pumpkins). On the other hand, Centris and Krameria genera presented a more intricate distribution pattern, since their interaction is more complex. Centris is a diverse group that uses other floral resources than those provided by the Krameriacea family, which has probably influenced its distribution, also. However, the results obtained for Krameria showed the influence of clime in its distribution and a stronger relationship with Centris in some cases. Finally, the importance of including biotic data in the species distribution modelling process was also demonstrated, resulting in a general increase in the models accuracy and also altering future scenarios projection, considering climate changes. Stronger interaction, such as the host-parasite bee species of Bombus showed more conspicuous results than those found for Krameria and Centris. The techniques, especially distribution modelling, made an important contribution to the analyses. However, in spite of being increasingly used, distribution modelling demands more robust tests and techniques to evaluate the accuracy of final models. Besides, an additional challenge to be achieved consists in the increase and improvement of species occurrence data, mainly in Brazil. An additional survey effort is necessary, especially in specific areas, as well as the conservation and data digitalization of biological collections. However, the techniques used here showed a great potential to be further explored in other analyses, involving different biological issues, other taxonomic groups and other data layers.
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