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Melissa Amarello; Jeffrey J. Smith. |
Coloration may serve a variety of behavioral (e.g., crypsis, communication) and physiological (e.g., thermoregulation, protection) functions for terrestrial ectotherms. However, optimal coloration for a given function may vary over environments (spatial or temporal) or conflict with other functions. Physiological color change (rapid change due to movement of pigment granules within chromatophores) may be an adaptation to resolve conflicting selective pressures on coloration. The proximate factors related to physiological color change are well known in many animals, but few studies have investigated the ecological or evolutionary implications of this behavior. Here, we present alternative hypotheses for physiological color change and discuss biotic and... |
Tipo: Poster |
Palavras-chave: Ecology; Evolutionary Biology. |
Ano: 2011 |
URL: http://precedings.nature.com/documents/6711/version/1 |
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Ingo Ebersberger; Matthias Gube; Sascha Strauss; Anne Kupczok; Martin Eckart; Kerstin Voigt; Erika Kothe; Arndt von Haeseler. |
Fungi are abundant in the biosphere. They have fascinated mankind as far as written history goes and have considerably influenced our culture. In biotechnology, cell biology, genetics, and life sciences in general fungi constitute relevant model organisms. Once the phylogenetic relationships of fungi are stably resolved individual results from fungal research can be combined into a holistic picture of biology. However, and despite recent progress, the backbone of the fungal phylogeny is not yet fully resolved. Especially the early evolutionary history of fungi and the order or below-order relationships within the ascomycetes remain uncertain. Here we present the first phylogenomic study for a eukaryotic kingdom that merges all publicly available fungal... |
Tipo: Manuscript |
Palavras-chave: Ecology; Bioinformatics. |
Ano: 2009 |
URL: http://precedings.nature.com/documents/2901/version/1 |
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Renaud R. Y. Lahaye; Vincent Savolainen; Sylvie Duthoit; Olivier Maurin; Michelle van der Bank. |
A DNA barcode consists of a standardized short sequence of DNA (400-800bp) used to identify the taxonomic species a small organic fragment belongs to. Even though it has been easy to discriminate animal species by using the mitochondrial gene _cox1_, this is still difficult for plants seeing that the mitochondrial genome is not variable enough on the species level. During the Second International Barcode of Life Conference in Tapei (September 2007), different plastid regions were proposed as potential plant DNA barcodes, such as _atpF-atpH_ and _psbK-psbI_, but no consensus on which region to use was reached during the meeting. The largest plant DNA barcoding study to date proposed _matK_ as the best candidate and suggested that in combination with... |
Tipo: Manuscript |
Palavras-chave: Ecology; Plant Biology. |
Ano: 2008 |
URL: http://precedings.nature.com/documents/1896/version/1 |
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Lev V. Kalmykov; Vyacheslav L. Kalmykov. |
The origin of species richness is one of the most widely discussed questions in ecology. The absence of unified mechanistic model of competition makes difficult our deep understanding of this subject. Here we show such a two-species competition model that unifies (i) a mechanistic niche model, (ii) a mechanistic neutral (null) model and (iii) a mechanistic violation of the competitive exclusion principle. Our model is an individual-based cellular automaton. We demonstrate how two trophically identical and aggressively propagating species can stably coexist in one stable homogeneous habitat without any trade-offs in spite of their 10% difference in fitness. Competitive exclusion occurs if the fitness difference is significant (approximately more than 30%).... |
Tipo: Manuscript |
Palavras-chave: Ecology; Bioinformatics; Plant Biology; Evolutionary Biology. |
Ano: 2012 |
URL: http://precedings.nature.com/documents/7089/version/1 |
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Eduardo Moreno. |
Of the tribal hunter gatherers still in existence today, some lead lives of great violence, whereas other groups live in societies with no warfare and very little murder^1,2,3,4,5^. Here I find that hunter gatherers that belong to mitochondrial haplotypes L0, L1 and L2 do not have a culture of ritualized fights. In contrast to this, almost all L3 derived hunter gatherers have a more belligerent culture that includes ritualized fights such as wrestling, stick fights or headhunting expeditions. This appears to be independent of their environment, because ritualized fights occur in all climates, from the tropics to the arctic. There is also a correlation between mitochondrial haplotypes and warfare propensity or the use of murder and suicide to resolve... |
Tipo: Manuscript |
Palavras-chave: Ecology; Genetics & Genomics; Earth & Environment; Evolutionary Biology. |
Ano: 2010 |
URL: http://precedings.nature.com/documents/4303/version/1 |
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Geoffroy, Benjamain; Alfonso, Sebastien; Sadoul, Bastien; Blumstein, Daniel T. |
Humans currently occupy all continents and by doing so, modify the environment and create novel threats to many species; a phenomenon known as human-induced rapid environmental changes (HIREC). These growing anthropogenic disturbances represent major and relatively new environmental challenges for many animals, and invariably alter selection on traits adapted to previous environments. Those species that survive often have moved from their original habitat or modified their phenotype through plasticity or genetic evolution. Based on the most recent advances in this research area, we predict that wild individuals with highly plastic capacities, relatively high basal stress level, and that are generally shy—in other words, individuals displaying a reactive... |
Tipo: Text |
Palavras-chave: Coping style; Antipredator behavior; Evolution; Stress physiology; Ecology; Predation; Urbanization; Pollution. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00664/77564/79528.pdf |
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Silvanus G. Otieno; Jesse T. Njoka; Truman P. Young; Stephen M. Mureithi; Robinson K. Ngugi. |
The controversy that has surrounded herbivory studies in the last few decades prompted our investigation to establish the extent to which herbivore optimisation hypothesis or compensatory growth evidence is real. We used the traditional movable cage method to collect primary productivity data on herbage, functional groups and key individual grass species in various controlled large herbivore treatments in an east African savanna. The herbivore treatments in triplicate blocks included cattle, wild herbivores with and without mega herbivores and combinations of cattle and wild herbivores also with and without mega herbivores. The findings revealed that at herbage level, most grazed treatments (four out of five) had higher productivity than the ungrazed... |
Tipo: Manuscript |
Palavras-chave: Ecology. |
Ano: 2009 |
URL: http://precedings.nature.com/documents/3452/version/1 |
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Rey Donne Papa; Roberto Pagulayan; Alicia Ely Pagulayan. |
Zooplankton are considered to be important members of the lake ecosystem. The abundance and composition of which are due to several factors, for example, the impact of intensive size-selective predation by planktivorous fishes residing in the lake. In this study, the abundance and composition of zooplankton found in the vicinity of Isla Napayun - a known fishing ground of the freshwater sardine, Sardinella tawilis (Herre 1927) was analyzed using samples taken from vertical plankton tows from the 10 and 20 m depths in 2 sampling sites from the said area. These were then compared with the stomach contents of S. tawilis taken during the same period. Results show that there were 4 genera of Copepoda, 4 genera of Cladocera and 2 genera of Rotifera found in... |
Tipo: Presentation |
Palavras-chave: Ecology; Earth & Environment. |
Ano: 2007 |
URL: http://precedings.nature.com/documents/684/version/1 |
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Elisabeth Jüschke; Bernd Marschner. |
The reuse of reclaimed wastewater for irrigation of agricultural fields greatly influences the activity of soil microorganisms through the input of organic compounds. Due to the production of exoenzymes by microorganisms for the decomposition of substrates it can be assumed that the irrigation with treated wastewater (TWW) has a strong influence on the soil enzyme pool. In this study the activity of ten exoenzymes, which catalyses processes in C, N and P nutrient cycles, were determined in 3 different soils in 0-10, 10-20, 20-30, 30-50, 50-70 and 70-100 cm soil depth. The soils were used for agriculture and irrigated with reclaimed wastewater reused after a secondary treatment step. Additionally a control after freshwater irrigation was studied. Due to the... |
Tipo: Presentation |
Palavras-chave: Ecology; Microbiology; Earth & Environment. |
Ano: 2011 |
URL: http://precedings.nature.com/documents/6278/version/1 |
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Lazhar Mhadhbi; Sara Pérez Fernandez; Diego Real Conde; Moncef Boumaiza; Ricardo Beiras. |
Perfluorooctane sulfonate (PFOS) is a persistent organic pollutant whose potential toxicity is causing great concern. In the present study, we used two crustaceans (_Daphnia magna_, _Siriella armata_), echinoid embryos (_Paracentrotus lividus_) and turbot (_Scophthalmus maximus L._) embryos and larvae to investigate the acute toxicity of this compound. The marine species _S. armata_ exhibited greater sensitivity than the freshwater species _D. magna_. In the 48-h acute toxicity test the median lethal concentration was 10.96 mg/L for _S. armata_ and 87.46 mg/L for _D. magna_. In the 96h toxicity test, turbot showed the lowest EC50 (0.155 mgL-1), whilst the EC50 for _S. armata_ was 7.92 mgL-1 which was approximately three times lower than that for sea urchin... |
Tipo: Poster |
Palavras-chave: Biotechnology; Chemistry; Ecology; Earth & Environment. |
Ano: 2010 |
URL: http://precedings.nature.com/documents/4657/version/1 |
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Jessica Halofsky; David L. Peterson. |
Climate change presents a major challenge to natural resource managers both because of the magnitude of potential effects of climate change on ecosystem structure, process, and function, and because of the uncertainty associated with those potential ecological effects. Concrete ways to adapt to climate change are needed to help natural resource managers take the first steps to incorporate climate change into management and take advantage of opportunities to balance the negative effects of climate change. We initiated a climate change adaptation case study at Olympic National Forest and Olympic National Park to determine how to adapt management of federal lands on the Olympic Peninsula to climate change. As a part of the case study process, we conducted a... |
Tipo: Poster |
Palavras-chave: Ecology. |
Ano: 2010 |
URL: http://precedings.nature.com/documents/5239/version/1 |
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Richard Svanbäck; Mario Pineda-Krch; Michael Doebeli. |
Traits determining ecological interactions and dynamics are generally subject to natural selection. That genetically based individual variation in ecological traits can influence population dynamics has interested population biologist from various perspectives. Population ecologists recognized the need to incorporate individual variation in models of population regulation, while evolutionary biologists wish to understand genetic and evolutionary dynamics, e.g. of life history traits, in density-regulated populations. But how does adaptation in ecological traits affect population dynamics? In this project we investigated how ecological dynamics changes as a consequence of adaptive evolution in ecological traits using an individual-based predator-prey model. |
Tipo: Poster |
Palavras-chave: Ecology; Evolutionary Biology. |
Ano: 2007 |
URL: http://precedings.nature.com/documents/57/version/1 |
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Wilfred O. Odadi; Moses Karachi; Shaukat Abdulrazak; Truman Young. |
Savanna ecosystems are vital for both economic and biodiversity values. In savannas worldwide, management decisions are based on the concept that wildlife and livestock compete for grassland resources[1-4], yet there are virtually no experimental data to support this assumption[1]. Specifically, the critical assessment of whether or not wild ungulates alter livestock performance (e.g., weight gain, reproduction or survival) has rarely been carried out, although diminished performance is an essential prerequisite for inferring competition[1]. Here we use a large-scale experiment in a semi-arid savanna in Kenya to show that wild ungulates do depress cattle performance (weight gain) during the dry season, indicating a competitive effect, but enhance cattle... |
Tipo: Manuscript |
Palavras-chave: Ecology. |
Ano: 2010 |
URL: http://precedings.nature.com/documents/4828/version/1 |
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Steven J. Wagstaff; Ilse Breitwieser; Christopher Quinn; Motomi Ito. |
Biogeographic relationships in the southern hemisphere have puzzled biologists for the last two centuries. Once joined to form the supercontinent Gondwana, Africa, Antarctica, Australia, New Zealand and South America are widely separated by the Pacific and Indian oceans. Sir Joseph Hooker was the first to suggest that Antarctica served as a corridor for plant migration not unlike the land-bridges in the northern hemisphere. While the Antarctic flora was largely erased by glaciation during the Pleistocene, at least some of these Antarctic plant communities found refuge on the subantarctic islands. Here we provide support for the hypothesis that giant herbs persisted in the subantactic islands prior to the onset of Pleistocene glaciation, then dispersed... |
Tipo: Manuscript |
Palavras-chave: Ecology; Plant Biology; Evolutionary Biology. |
Ano: 2007 |
URL: http://precedings.nature.com/documents/1272/version/1 |
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Siddhartha Sankar Mukhopadhyay. |
Natural agricultural production functions in open system, where energy and matter are exchanged freely between geosphere (especially pedosphere), biosphere, and atmosphere. The self regulation of biophysical processes in these spheres is crucial for global sustainability. However, modern farming practices have stressed the system to the extent that damaged C, N, and P cycles are threatening catastrophic consequences. High food-wastage coupled with high food price, high soil fertility zones but low crop productivity, and highly productive irrigated farming marred with ecological disasters are examples of global paradoxes associated with modern farming. High incidence of pesticide residues in soil and water bodies, low use efficiency of agricultural inputs,... |
Tipo: Presentation |
Palavras-chave: Chemistry; Ecology; Earth & Environment. |
Ano: 2012 |
URL: http://precedings.nature.com/documents/6900/version/1 |
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Registros recuperados: 900 | |
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