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Phenology of a Southern Population of Mountain Pine Beetle (<i>Dendroctonus ponderosae</i>)McManis, Anne Elise 01 May 2018 (has links)
Mountain pine beetle (Dendroctonus ponderosae, Hopkins) is a major disturbance agent in pine ecosystems of western North America. Adaptation to local climates has resulted in primarily univoltine (one generation per year) generation timing across a thermally diverse latitudinal gradient. We hypothesized that this pattern in total development time is shaped by selection for slower developmental rates, altered developmental thresholds, or oviposition rates in southern populations inhabiting warmer climates. To investigate traits responsible for latitudinal differences we measured lifestage-specific development of southern mountain pine beetle eggs, larvae and pupae across a range of temperatures. We also describe and model oviposition of southern US MPB. Using a novel technique that included frequent X-ray imaging, oviposition rate and fecundity were estimated separately and shown to both be significant and independent sources of variation. When compared with previously collected data for a northern MPB population, total oviposition time predicted for southern MPB at a constant 20°C was slightly longer than that of northern MPB, but the delay was too small to account for significant differences between the populations in total development time.
Developmental rate curves for eggs, larvae, and pupae were fit using maximum posterior likelihood estimation with a Bayesian prior to improve fit stability. When compared to previously published data for a northern population (Régnière et al. 2012), observed developmental rates of the southern and northern populations were similar across all studied lifestages at 20 and 25°C, although southern individuals were generally faster at temperature extremes (10 and 27°C). These findings were inconsistent with our hypothesis that southern individuals would have consistently slower rates. Optimal development of southern individuals occurred at higher temperatures, with higher development thresholds, as compared with northern individuals. Our results suggest that evolved traits in the remaining unstudied lifestage, teneral (i.e., pre-emergent) adult, likely influence latitudinal differences in mountain pine beetle generation time.
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Descriptive Analysis of Ground Frost Patterns in Sweden (1991-2007)Mellberg, Jenny January 2008 (has links)
No description available.
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Effects of climate on phenological synchrony between butterflies and their host plantsPosledovich, Diana January 2015 (has links)
Shifts in species’ phenologies and phenological asynchronies between the interacting organisms have received a lot of attention in the context of climate change. Changes in temporal overlap between species, caused by phenological asynchrony, make species depending on one another become so separated in time that they can no longer interact. This may have important consequences both for single species, like fluctuations in abundances, and for the functioning of whole communities by creating mismatches between trophic levels and rearrangements of community structure. This thesis focuses on the impact of temperatures on spring timing and phenological synchrony in a herbivorous insect – host plant system, consisting of the orange tipbutterfly Anthocharis cardamines and five of its Brassicaceae host plant species. Paper I demonstrates that diapause duration and winter thermal conditions can determine the timing of spring emergence in the herbivore, and these traits may differ between species with different feeding strategies. In paper II we show that thermal reaction norms of post-winterdevelopment of A. cardamines display cogradient latitudinal variation.Paper III shows that temperature-mediated phenological plasticity of A. cardamines butterflies and a majority of the most used host plant species is similar within populations originating from different latitudes. Thus, the species’ timing appeared well conserved in response to thermal variation. In paper IV we explored the importance of the butterfly’s adult emergence and thermal conditions on the succeeding part of the butterfly’s life-cycle – larval development. The outcome from the interaction was examined for both the insect and the plant side. The degree in phenological overlap between the female butterflies and host plants as well as temperatures during larval development were found to influence larval development but had no effect on plant reproductive fitness. The four papers of the presented thesis demonstrate that developmental preadaptations, evolvedin a herbivore to maintain phenological synchrony with host plants across yearly variation of spring conditions, can prevent disruption of the interaction under a wide range of temperatures. This indicates that temporary constrained interactions are not always vulnerable to decoupling, particularly if they involve generalist strategy. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Submitted.</p> / Ekoklim
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Gradiente latitudinal de riqueza de espécies e regra de Rapoport : uma meta análise /Nardy, Olavo. January 2008 (has links)
Orientador: Harold Gordon Fowler / Banca: Adler Guilherme Viadana / Banca: Wesley Augusto Conde Godoy / Banca: Marcelo Nogueira Rossi / Banca: Sofia Campiolo / Apresenta anexos em CD-ROM / Resumo: Foram realizadas meta análises com o Gradiente Latitudinal de Riqueza de espécies, a Regra de Rapoport e sua interação para vertebrados ao longo de todo o Globo. Com os resultados é possível concluir que ambos os padrões são generalizáveis e consistentes para todos os grupos de vertebrados, no entanto nenhuma variável moderadora associada à característica ecológicas, biológicas ou biogeográficas pode ser confirmada como principal condicionante destes padrões, não apresentando padrões constantes entre hemisférios, continentes, classes, número de províncias biogeográficas, tamanho corpóreo ou outra variável analisada. Foram utilizados como effect sizes a inclinação da reta de regressão ou o coeficiente angular da regressão linear (b) e o Coeficiente de Correlação de Spearman corrigido por Z-Fisher (r), entre estes dois, o segundo apresentou melhores resultados referentes as suas adequações e restrições associadas a meta análise, tais como normalidade dos dados e pressupostos de viés de publicações. As variáveis moderadoras associadas a características metodológicas como poder do teste, significância e tamanho amostral apresentaram maior poder explicativo do padrão do que as demais variáveis, sugerindo uma necessidade de se adotar um padrão mais rigoroso no delineamento de estudos que abordem este tema. Para a Regra de Rapoport o método utilizado na confecção do teste foi a variável moderadora mais evidente para a detecção de uma estrutura nos dados. / Abstract: In the present work where made meta analysis with Latitudinal Gradient of Species richness, Rapoport Rule and their interaction for vertebrates along a global scale. With the results is possible to conclude that both patterns are general for vertebrates, nevertheless none of the ecological, biological or biogeographical moderators variables could be confirmed as the primary cause of the patterns, don't showing any constant pattern between hemispheres, continents, classes, number of biogeographical provinces or other analyzed variable. It will be used as effect size the angular coefficient or the linear regression (b) and the Spearman Correlation Coefficient transformed by Z-Fisher (r), among these two effect size, the second presents best results associated with restrictions and fits inherent to meta analysis, such as normality and publication bias. The moderator's variables associates with methodological issues, like statistical power, significance and sample size show higher explanation strength than the others variables, suggesting a necessity of more strength methods in the studies that claim these global patterns. For Rapoport Rule the method used to do the test was the moderator variable more evident to detect some data structure. / Doutor
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Geografická variabilita velikosti mateřských kolonií jeskynních druhů netopýrů / Geographic variability in the size of maternity colonies of cave batsOppelová, Tereza January 2016 (has links)
Main goal of this thesis was to compare geographical variability of sizes of colonies in the relationship with the type of roost of 6 models of originally cave bats species: Greater mouse-eared bat (Myotis myotis), Geoffroy's bat (Myotis emarginatus), Common bent-wing bat (Miniopterus schreibersii), Greater horseshoe bat (Rhinolophus ferrumequinum), Lesser horseshoe bat (Rhinolophus hipposideros) a Mediterranean horseshoe bat (Rhinolophus euryale). The selected data set was also analyzed the possible influence of the composition of land cover in roosts around the variability of the size of the colonies. Based on compilation of literature and active communication with regional bat-monitoring coordinators, entries about size of colonies from 2 603 locations in 24 countries of Europe were collected. 1 952 entries were from roosts in buildings and 651 from caves. Based on statistical analysis, conclusive influence of type of roost on size of colonies by M. schreibersii, M. myotis a R. hipposideros was discovered. While in M. schreibersii and M. myotis are human colonies in smaller buildings, in R. hipposideros by contrast, they are larger. Simultaneously, north-west gradient in geographical distribution of maternal bat- colonies in dependence on type of roost (caves vs. buildings): in southern areas...
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Phenotypic Variation in the Social Behaviour of the Spider Anelosimus studiosus Along a Latitudinal GradientRiechert, Susan, Jones, Thomas C. 01 June 2008 (has links)
We investigated the behavioural mechanism underlying the recently discovered latitudinal variation in the social structure of the spider Anelosimus studiosus through population censuses, behavioural interaction trials, reciprocal nest transplants to different temperature environments and breeding experiments. Nest censuses completed at replicated sites at 2° changes in latitude between south Florida (26°) and east Tennessee (36°) indicated that the dominant social structure is a solitary female nest. Multifemale nests consisting of cooperative females and their young first appeared in the populations at 30° latitude and increased in frequency of representation with further increases in latitude as did number of females within multifemale nests. Interaction trials showed that communication and physical contact underlie the two social structures. Females from solitary female nests and F1 offspring reared in the laboratory demanded space (asocial phenotype), whereas individuals of multifemale nest origin (from same and foreign nests) were attracted to one another (social phenotype). Field experiments further showed that (1) individuals that dispersed from multifemale nests dispersed shorter distances and (2) nest coalescence was observed only at the higher latitudes, coincident with the presence of multifemale nests. Habitat transplants suggested that the behaviour underlying social structure is not plastic in this system, and breeding experiments eliminated a cryptic species alternative to the presence of different social structure phenotypes. Although both asocial and social phenotypes were present at all latitudes, the frequency of the social phenotype was rare at lower latitudes.
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Latitudinal Variation in Lifetime Survival and Reproduction in a Burying BeetleLaidlaw, Clinton T. 01 March 2015 (has links) (PDF)
Temperature variation experienced across a latitudinal range is tied to changes in lifespan and life history across multiple taxa. Two patterns of adaptation to latitudinal temperature variation have been documented – counter-gradient (or co-gradient) variation, and local adaptation. To determine how natural selection has shaped life history variation in a burying beetle, Nicrophorus orbicollis, we quantified lifetime patterns of reproduction in two populations that represent the geographic and temperature extremes occupied by the species. Lifetime reproduction was quantified at two temperatures that represented conditions typical for each population. Burying beetles from different extremes of their geographic range show considerable variation in lifetime survival and reproduction at different temperatures. Patterns are generally consistent with the local adaptation hypothesis. However, at the higher temperature both populations have lower and equal numbers of offspring over a lifetime. High temperatures may create a constraint on offspring production because of the increased cost of maintaining the food source against bacterial decomposition. This temperature constraint on reproductive success may partially explain the absence of burying beetles from tropical environments, and may predict reductions in latitudinal range as global climate change proceeds.
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Countergradient variation and compensatory growth in Moor frog (Rana arvalis) along a replicated latitudinal gradientMallick, Sohini January 2022 (has links)
For evolution to occur over time, it is necessary for animals and plants to show phenotypic variation. If the individuals within populations of a species do not show observable differences among themselves, there will be a lack of driving force for natural selection to act on and decide which characteristic gets inherited from one generation to the next. It is hence important to study phenotypic variation, especially against environmental gradients such as latitude and altitude, which gives us an insight into the pattern of change according to essential factors such as temperature and length of seasons. The latter would impose time constraints on growing populations, leading to periods of unfavourable conditions limiting their growth and development. In many cases, such organisms would tend to compensate for the period of slow growth and catch up to the others that did not have to endure the same situation and grow to the same size as them. This study aims to find differences in three key larval life-history traits of the moor frog (Rana arvalis), namely metamorphic mass, larval period, and growth rate, and find what kind of pattern is observed in case of these phenotypic variations. It also aims to find differences in the strength of compensatory response between populations from lower and higher latitudes. A common garden experiment was conducted with populations originating from both sides of the Baltic Sea, ranging from southern Sweden and Latvia to central Finland and northern Sweden. It was expected that the northern populations would grow faster and show a countergradient variation pattern since they are faced with more strict time constraints at higher latitudes, but in most cases, we observed a co-gradient pattern, wherein the environmental effect amplifies the individual’s genetic predisposition instead of opposing it. We also observed a stronger compensatory response in the northern populations as compared to their southern counterparts. Effects of climate change and subsequent rise in temperatures making the environment unpredictable over time could be used to speculate about the reason behind the results obtained. Epigenetics could also be used as an approach to study long lasting changes in an organism’s gene expression to make it adapt better to changing conditions and hence show different patterns of variation from studies in the past. Studying such changes, expected or not, is important to keep up with the needs of the species that require conservation, and will help conservation biologists to formulate strategies that would be effective even in the face of constant change in the world.
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Morphological Variations in Jack Pine (Pinus Banksiana) Along its' Central to Northern Population RangesKellman, Lisa Marie 04 1900 (has links)
<p> The analysis of six jack pine populations along a north-south transect through the MacKenzie River Valley in the Northwest Territories revealed no significant latitudinal trends in cone and seed morphometric measurements. In attempting to determine whether any variations may be environmentally induced, Radial Growth Rates were, 1)compared between sites. and 2), were correlated with morphometric measurements. No significant results were produced. In correlating trait measurements between sites and between one another in order to determine whether migration may be producing trends, again no significant relatlonships were obtained. A comparison of jack pine with the similar species lodgepole pine suggests that if the same factors controlling the migration of lodgepole pine also control jack pine migration, wing loading should be less in more recent populations. However, this study indicates no significant results in this respect. It is suggested, however, that a further sampling south along the latitudinal transect may produce significant results.</p> / Thesis / Candidate in Philosophy
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Estrutura e composição de espécies arbóreas em um trecho de floresta ombrófila densa atlântica no litoral norte do estado de São Paulo e padrões de similaridade florística em escala regionalPrata, Eduardo Magalhães Borges [UNESP] 27 March 2009 (has links) (PDF)
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prata_emb_me_rcla.pdf: 2137879 bytes, checksum: f0087a39dbca5bca9a452e4b2037187e (MD5) / Este trabalho foi desenvolvido em um trecho de Floresta Ombrófila Densa Atlântica no Núcleo Picinguaba do Parque Estadual da Serra do Mar, litoral norte do Estado de São Paulo, município de Ubatuba-SP. A área de estudo corresponde a uma das parcelas amostrais (Parcela D) do Projeto Temático “Composição florística, estrutura e funcionamento da Floresta Ombrófila Densa dos Núcleos Picinguaba e Santa Virgínia do Parque Estadual da Serra do Mar” do Programa BIOTA-FAPESP. Nosso estudo foi estruturado em três capítulos. No Capítulo 1, objetivamos descrever a composição florística e a estrutura da comunidade arbórea em uma parcela de 1 ha; avaliar o padrão de distribuição espacial das espécies e; investigar a ocorrência de correlações entre a distribuição das espécies e as variáveis ‘altitude média’, ‘desnível topográfico’, ‘cobertura rochosa’, ‘presença de água na superfície do solo’, ‘distância do rio’ e ‘luz no interior da parcela’, através de uma CCA. No Capítulo 2, investigamos a distribuição da riqueza e da diversidade de espécies ao longo do perfil vertical, considerando os estratos adultos e regenerantes da comunidade, buscando responder em quais níveis de altura está presente o maior número de espécies arbóreas. No Capítulo 3, avaliamos a distribuição das espécies e os padrões de similaridade florística entre áreas de Floresta Ombrófila Densa das Terras Baixas e Submontana situadas ao longo de um gradiente latitudinal entre os Estados do Rio de Janeiro e Santa Catarina. Nossos resultados revelaram valores elevados de riqueza (161 spp) e diversidade (H' = 4,0) no hectare analisado. Observamos padrões de distribuição espacial aleatórios para a maioria das espécies na comunidade, onde apenas Euterpe edulis, Alsophila sternbergii e Coussarea meridionalis var. porophylla apresentaram padrão agregado... / This study was conducted in a stretch of Atlantic Rain Forest at Núcleo Picinguaba do Parque Estadual da Serra do Mar, northern coast of São Paulo State, municipality of Ubatuba-SP. The study area represents one of the sample plots (Plot D) of the Project Composição florística, estrutura e funcionamento da Floresta Ombrófila Densa dos Núcleos Picinguaba e Santa Virginia do Parque Estadual da Serra do Mar Programa BIOTA-FAPESP. Our study was structured in three chapters. In Chapter 1, we aimed to describe the floristic composition and tree structure in a plot of 1 ha; assess the pattern of spatial distribution of species and, to investigate the occurrence of correlations between species distribution and the variables 'average height', 'topographic gap', 'cover rock ', 'presence of water on soil surface', 'distance from the river' and 'light in the interior of the plot', through a CCA. In Chapter 2, we investigated species richness and diversity distribution along the vertical profile, involving both regenerating and adult strata, in order to answer which height levels show the greatest number of tree species. In Chapter 3, we assessed species distribution and the occurrence of patterns on floristic similarities between areas of Lowlands and Submontanes Atlantic Rain Forests areas along a latitudinal gradient between Rio de Janeiro and Santa Catarina states. Our results revealed high richness (161 spp) and diversity (H' = 4.0) values in the area examined. We observed random patterns on spatial distribution for most species in the community, where only Euterpe edulis, Alsophila sternbergii and Coussarea meridionalis var. porophylla showed clumped patterns. Significant correlations between species and environmental variables matrices were detected for axis 1 of CCA (p = 0.001). The regenerating stratum showed greater floristic richness than adult stratum and higher values... (Complete abstract click electronic access below)
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