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Gazis Romina - - 2011
The estimation of species diversity in fungal endophyte communities is based either on species counts or on the assignment of operational taxonomic units (OTUs). Consequently, the application of different species recognition criteria affects not only diversity estimates but also the ecological hypotheses that arise from those observations. The main objective ...
Hudson Irene L - - 2011
Self-Organising Map (SOM) clustering methods applied to the monthly and seasonal averaged flowering intensity records of eight Eucalypt species are shown to successfully quantify, visualise and model synchronisation of multivariate time series. The SOM algorithm converts complex, nonlinear relationships between high-dimensional data into simple networks and a map based on ...
Hoang Tham C - - 2011
Endosulfan is an insecticide which has been widely used in agriculture. The technical grade material consists of two isomers (alpha and beta). Under natural environmental conditions, endosulfan is metabolized through oxidation and the main metabolite in the environment is endosulfan sulfate. Most ecotoxicology research has been conducted with technical grade ...
Ubierna Nerea - - 2011
Conductance to CO(2) inside leaves, known as mesophyll conductance (g(m) ), imposes large limitations on photosynthesis. Because g(m) is difficult to quantify, it is often neglected in calculations of (13) C photosynthetic discrimination. The "soluble sugars method" estimates g(m) via differences between observed photosynthetic discrimination, calculated from the δ(13) C ...
Goldberg Emma E - - 2011
Geographic characters-traits describing the spatial distribution of a species-may both affect and be affected by processes associated with lineage birth and death. This is potentially confounding to comparative analyses of species distributions because current models do not allow reciprocal interactions between the evolution of ranges and the growth of phylogenetic ...
Petrin Zlatko - - 2011
Much recent ecological research has centred on the interrelations between species diversity and ecological processes. In the present study, I show how species traits may aid in comprehending ecology by studying the link between an environmental variable and functional traits. I examined the composition of species traits with a theoretically ...
Bray Rodney A - - 2011
Three species of bucephaline bucephalids are described from Sphyraena putnamae Jordan & Seale and distinguished from related forms using visual keys. Rhipidocotyle khalili Nagaty, 1937 is illustrated and measurements given. Rhipidocotyle bartolii n. sp. [syns R. longicirrus (Nagaty, 1937) of Bartoli & Bray (2005); and possibly Bucephalopsis arcuatus (Linton, 1900) ...
Stadler Tanja - - 2011
In this article, I develop a methodology for inferring the transmission rate and reproductive value of an epidemic on the basis of genotype data from a sample of infected hosts. The epidemic is modeled by a birth-death process describing the transmission dynamics in combination with an infinite-allele model describing the ...
Yakubu Abdul-Aziz - - 2011
Overfishing, pollution and other environmental factors have greatly reduced commercially valuable stocks of fish. In a 2006 Science article, a group of ecologists and economists warned that the world may run out of seafood from natural stocks if overfishing continues at current rates. In this paper, we explore the interaction ...
Hallgren Stefan - - 2011
Behaviour studies are used in toxicology research as they are excellent tools to measure physiological end-points caused by exogenous chemicals. In mammals both reproductive and non-reproductive behaviours have been used for a long period of time, whereas in teleost fishes non-reproductive behaviours have received little attention compared to reproductive behaviours. ...
Angert Amy L - - 2011
Ecology Letters (2011) ABSTRACT: Although some organisms have moved to higher elevations and latitudes in response to recent climate change, there is little consensus regarding the capacity of different species to track rapid climate change via range shifts. Understanding species' abilities to shift ranges has important implications for assessing extinction ...
Wiens John J - - 2011
Ecology Letters (2011) ABSTRACT: What explains the striking variation in local species richness across the globe and the remarkable diversity of rainforest sites in Amazonia? Here, we apply a novel phylogenetic approach to these questions, using treefrogs (Hylidae) as a model system. Hylids show dramatic variation in local richness globally ...
Alberto Filipe - - 2011
Ocean currents are expected to be the predominant environmental factor influencing the dispersal of planktonic larvae or spores; yet, their characterization as predictors of marine connectivity has been hindered by a lack of understanding of how best to use oceanographic data. We used a high-resolution oceanographic model output and Lagrangian ...
Sallan Lauren Cole - - 2011
Predator-prey interactions are thought by many researchers to define both modern ecosystems and past macroevolutionary events. In modern ecosystems, experimental removal or addition of taxa is often used to determine trophic relationships and predator identity. Both characteristics are notoriously difficult to infer in the fossil record, where evidence of predation ...
Mendyk Robert W - - 2011
Captivity provides many opportunities for studying the reproductive biology of varanid lizards (Family: Varanidae; genus: Varanus). This article presents reproductive data for 12 varanid species maintained in captivity at the Bronx Zoo between 1977 and 2010. Five species, V. prasinus, V. beccarii, V. melinus, V. mertensi, and V. ornatus have ...
Shinzawa Hideyuki - - 2011
An analytical technique based on kernel matrix representation is demonstrated to provide further chemically meaningful insight into partial least squares (PLS) regression models. The kernel matrix condenses essential information about scores derived from PLS or principal component analysis (PCA). Thus, it becomes possible to establish the proper interpretation of the ...
Merrill Richard M - - 2011
Premating behavioral isolation is increasingly recognized as an important part of ecological speciation, where divergent natural selection causes the evolution of reproductive barriers. A number of studies have now demonstrated that traits under divergent natural selection also affect mate preferences. However, studies of single species pairs only capture a snapshot ...
Réjou-Méchain Maxime - - 2011
Abstract Little is known about the combined impact of habitat filtering and dispersal limitation on species turnover patterns. To gain new insights, we constructed a spatially explicit community model wherein we controlled dispersal distances, the strength of habitat filtering, and the grain of habitat heterogeneity to study the distance decay ...
Ferguson Grant - - 2011
Temperature measurements have been used by a variety of researchers to gain insight into groundwater discharge patterns. However, much of this research has reduced the problem to heat and fluid flow in one dimension for ease of analysis. This approach is seemingly at odds with the goal of determining spatial ...
Jørgensen Christian - - 2011
Abstract Since Smith and Fretwell's seminal article in 1974 on the optimal offspring size, most theory has assumed a trade-off between offspring number and offspring fitness, where larger offspring have better survival or fitness, but with diminishing returns. In this article, we use two ubiquitous biological mechanisms to derive the ...
Miller Tom E X - - 2011
Abstract Population models that combine demography and dispersal are important tools for forecasting the spatial spread of biological invasions. Current models describe the dynamics of only one sex (typically females). Such models cannot account for the sex-related biases in dispersal and mating behavior that are typical of many animal species. ...
Ohtaka Akifumi - - 2011
Based on new specimens, two freshwater papillate tubificines, Spirosperma apapillatus (Lastočkin in Lastočkin and Sokolskaja, 1953 ) and Embolocephalus nikolskyi (Lastočkin in Lastočkin and Sokolskaja, 1953 ) are redescribed, and geographic distributions are shown for these two species and E. yamaguchii ( Brinkhurst, 1971 ) in the Japanese archipelago. A ...
Liu Yonghuai - - 2011
For accurate registration of overlapping free form shapes, different points in one shape must select different points in another as their most sensible correspondents. To reach this ideal state, in this paper we develop a novel algorithm to penalize those points in one shape that select the same closest point ...
Salesa Manuel J - - 2011
In a recent paper, Eronen et al. (2010; hereafter EEFJ) observe differences in occlusal morphology, tooth crown height, and mesowear pattern between populations of the Miocene tridactyl equid Anchitherium from Spain and Germany, proposing that Spanish Anchitherium underwent adaptive evolution to local or regional arid conditions. However, these authors do ...
Gompert Zachariah - - 2011
Müllerian mimicry, where groups ofchemically defended species display a common warning color pattern and thereby share the cost of educating predators, is one of the most striking examples of ecological adaptation. Classic models of Müllerian mimicry predict that all unpalatable species of a similar size and form within a community ...
Ekram Azim M - - 2011
Dynamic linear modeling (DLM) analysis was performed to identify the long-term temporal trends of two toxic components of the technical chlordane pesticide, α- and γ-chlordane, in skinless-boneless muscle tissues of a number of sport fish species in Lake Erie. Our analysis considers the fish length as a covariate of the ...
Arroyave Jairo - - 2011
Phylogenetic relationships within the family Alestidae were investigated using parsimony, maximum likelihood, and Bayesian approaches based on a molecular dataset that included both nuclear and mitochondrial markers. Multiple representatives of all but two of the recognized alestid genera were included, which allowed for testing previous hypotheses of intergeneric relationships and ...
Maddin Hillary C - - 2011
High levels of morphological homoplasy have hindered progress in understanding morphological evolution within gymnophione lissamphibians. Stemming from the hypothesis that the braincase has the potential to yield phylogenetic information, the braincases of 27 species (23 genera) of gymnophione amphibians were examined using high-resolution micro-computed tomography and histologically prepared specimens. Morphology ...
Branch Trevor A - - 2011
There are differences in perception of the status of fisheries around the world that may partly stem from how data on trends in catches over time have been used. On the basis of catch trends, it has been suggested that about 70% of all stocks are overexploited due to unsustainable ...
Waxman D - - 2011
The fixation probability is determined when population size and selection change over time and differs from Kimura's result, with long-term implications for a population. It is found that changes in population size are not equivalent to the corresponding changes in selection and can result in less drift than anticipated.
Rémy Alice - - 2011
1. Individuals should benefit from settling in high-quality habitats, but dispersers born under favourable conditions have a better physical condition and should therefore be more successful at settling in high-quality habitats. 2. We tested these predictions with root voles (Microtus oeconomus) by a manipulation of individual condition through litter-size enlargement and reduction ...
Chan Caroline - - 2011
A dynamic model was developed to project mercury concentrations in common biomarkers of exposure in response to changes in mercury concentrations in predatory fish from local waters. The model predicts biomarkers in susceptible populations for intake rates representing the mean, 90(th) , 95(th) , and 99(th) percentiles of populations of ...
Miller T L - - 2011
SUMMARYThe taxonomy of trematodes of Great Barrier Reef (GBR) fishes has been studied in some detail for over 20 years. Understanding of the fauna has been informed iteratively by approaches to sampling, understanding of morphology, the advent of molecular methodology and a feed-back loop from the emergent understanding of host ...
Ellner Stephen P - - 2011
Rapid contemporary evolution due to natural selection is common in the wild, but it remains uncertain whether its effects are an essential component of community and ecosystem structure and function. Previously we showed how to partition change in a population, community or ecosystem property into contributions from environmental and trait ...
Zeng Ming - - 2011
In this study, a total of 40 tests of the toxicity of 8 halogenated benzenes to five algal species were performed. The result demonstrated that the toxicity of halogenated benzenes to five algal species was directly related to the hydrophobicity of the chemicals and the lipid content of the algae. ...
Kristensen Esben Astrup - - 2011
Increasing human impact on stream ecosystems has resulted in a growing need for tools helping managers to develop conservations strategies, and environmental monitoring is crucial for this development. This paper describes the development of models predicting the presence of fish assemblages in lowland streams using solely cost-effective GIS-derived land use ...
Coste Sabrina - - 2011
The maintenance in the long run of a positive carbon balance under very low irradiance is a prerequisite for survival of tree seedlings below the canopy or in small gaps in a tropical rainforest. To provide a quantitative basis for this assumption, experiments were carried out to determine whether construction ...
Li Feng F Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City 66160, United - - 2011
A predominant pathway of xenobiotic-induced toxicity is initiated by bioactivation. Characterizing reactive intermediates will provide information on the structure of reactive species, thereby defining a potential bioactivation mechanism. Because most reactive metabolites are not stable, it is difficult to detect them directly. Reactive metabolites can form adducts with trapping reagents, ...
Chaudhuri Abhishek - - 2011
We present a simple two-state model to understand the size-dependent endocytosis of nanoparticles. Using this model, we elucidate the relevant energy terms required to understand the size-dependent uptake mechanism and verify it by correctly predicting the behavior at large and small particle sizes. In the absence of interactions between the ...
Moore S M - - 2011
Many generalist pathogens are influenced by the spatial distributions and relative abundances of susceptible host species. The spatial structure of host populations can influence patterns of infection incidence (or disease outbreaks), and the effects of a generalist pathogen on host community dynamics in a spatially heterogeneous community may differ from ...
Lou P - - 2011
The circadian clock serves to coordinate physiology and behavior with the diurnal cycles derived from the daily rotation of the earth. In plants, circadian rhythms contribute to growth and yield and, hence, to both agricultural productivity and evolutionary fitness. Arabidopsis thaliana has served as a tractable model species in which ...
Johnston Matthew W - - 2011
Pterois volitans and Pterois miles, two sub-species of lionfish, have become the first non-native, invasive marine fish established along the United States Atlantic coast and Caribbean. The route and timing of the invasion is poorly understood, however historical sightings and captures have been robustly documented since their introduction. Herein we ...
Schimak Mario P - - 2012
Traditional morphological identification of invertebrate marine species is limited in early life history stages for many taxa. In this study, we demonstrate, by example of Vestimentiferan tubeworms (Siboglinidae, Polychaeta), that the simultaneous fluorescence in situ hybridization (FISH) of both eukaryotic host and bacterial symbiont cells is possible on a single ...
Silva Alexander M - - 2011
Computational investigations in catalysis frequently use model clusters to represent realistically the catalyst and its reaction sites. Detailed knowledge of the molecular charge, thus electronic density, of a cluster would then allow physical and chemical insights of properties and can provide a procedure to establish their optimum size for catalyst ...
Bonner Simon J - - 2011
Summary Petersen-type mark-recapture experiments are often used to estimate the number of fish or other animals in a population moving along a set migration route. A first sample of individuals is captured at one location, marked, and returned to the population. A second sample is then captured farther along the ...
Packard Gary C - - 2011
Three data sets from the recent literature were submitted to new analyses to illustrate the rotational distortion that commonly accompanies traditional allometric analyses and that often causes allometric equations to be inaccurate and misleading. The first investigation focused on the scaling of evaporative water loss to body mass in passerine ...
Tsai Jeng-Wei - - 2011
Long-term metal exposure risk assessment for aquatic organism is a challenge because the chronic toxicity of chemical is not only determined by the amount of accumulated chemical but also affected by the ability of biological regulation or detoxification of biota. We quantified the arsenic (As) detoxification ability of tilapia and ...
Aze Tracy - - 2011
We present a complete phylogeny of macroperforate planktonic foraminifer species of the Cenozoic Era (∼65 million years ago to present). The phylogeny is developed from a large body of palaeontological work that details the evolutionary relationships and stratigraphic (time) distributions of species-level taxa identified from morphology ('morphospecies'). Morphospecies are assigned ...
Herrel Anthony - - 2011
Fish swimming is probably one of the most studied and best understood locomotor behaviors in vertebrates. However, many fish also actively exploit sediments. Because of their elongate body shape, anguilliform fishes are not only efficient swimmers but also very maneuverable. Consequently, many species live in complexly structured environments near the ...
Britton Kate - - 2011
In order to understand the behaviours and subsistence choices of Palaeolithic hunter-gatherers, it is essential to understand the behavioural ecology of their prey. Here, we present strontium isotope data from sequentially-sampled enamel from three reindeer (Rangifer tarandus ssp.) and a single bison (Bison cf. priscus) from the late Middle Palaeolithic ...
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