Quantitative assessment of the relationships among ecological, morphological and aesthetic values in a river rehabilitation initiative.

Science.gov (United States)

McCormick, Ashlee; Fisher, Karen; Brierley, Gary

2015-04-15

Promoting community support in rehabilitation efforts through incorporation of aesthetic considerations is an important component of environmental management. This research utilised a small-scale survey methodology to explore relationships among the ecological and morphological goals of scientists and the aesthetic goals of the public using the Twin Streams Catchment, Auckland, New Zealand, as a case study. Analyses using a linear model and a generalised linear mixed model showed statistically significant relationships between perceived naturalness of landscapes and their aesthetic ratings, and among ratings of perceived naturalness and ecological integrity and morphological condition. Expert measures of health and the aesthetic evaluations of the public were well aligned, indicating public preferences for landscapes of high ecological integrity with good morphological condition. Further analysis revealed participants used 'cues to care' to rate naturalness. This suggests that environmental education endeavours could further align values with these cues in efforts to enhance approaches to landscape sustainability. Copyright © 2014 Elsevier Ltd. All rights reserved.

Ecological and morphological patterns in communities of land snails of the genus Mandarina from the Bonin Islands.

Science.gov (United States)

Chiba, Satoshi

2004-01-01

The land snail genus Mandarina has undergone extensive radiation within the Bonin Islands in the west Pacific. The preferred above-ground vegetation heights of sympatric species were clearly different. They separated into arboreal, semi-arboreal, exposed ground and sheltered ground ecotypes. Shells of species with different ecotypes differ markedly, but shells of species with the same ecotype are very similar to each other. Shell morphologies of some phylogenetically distantly related species with the same ecotype were indistinguishable. Character evolution estimated parsimoniously using a phylogenetic tree suggests that the speciation among sympatric species is accompanied by ecological and morphological diversification. In addition, species coexistence of Mandarina is related to niche differentiation. The above findings suggest that ecological interactions among species contribute to the ecological and morphological diversification and radiation of these land snails in this depauperate environment.

Quantifying chaos for ecological stoichiometry.

Science.gov (United States)

Duarte, Jorge; Januário, Cristina; Martins, Nuno; Sardanyés, Josep

2010-09-01

The theory of ecological stoichiometry considers ecological interactions among species with different chemical compositions. Both experimental and theoretical investigations have shown the importance of species composition in the outcome of the population dynamics. A recent study of a theoretical three-species food chain model considering stoichiometry [B. Deng and I. Loladze, Chaos 17, 033108 (2007)] shows that coexistence between two consumers predating on the same prey is possible via chaos. In this work we study the topological and dynamical measures of the chaotic attractors found in such a model under ecological relevant parameters. By using the theory of symbolic dynamics, we first compute the topological entropy associated with unimodal Poincaré return maps obtained by Deng and Loladze from a dimension reduction. With this measure we numerically prove chaotic competitive coexistence, which is characterized by positive topological entropy and positive Lyapunov exponents, achieved when the first predator reduces its maximum growth rate, as happens at increasing δ1. However, for higher values of δ1 the dynamics become again stable due to an asymmetric bubble-like bifurcation scenario. We also show that a decrease in the efficiency of the predator sensitive to prey's quality (increasing parameter ζ) stabilizes the dynamics. Finally, we estimate the fractal dimension of the chaotic attractors for the stoichiometric ecological model.

Evolutionary conservatism and convergence both lead to striking similarity in ecology, morphology and performance across continents in frogs.

Science.gov (United States)

Moen, Daniel S; Irschick, Duncan J; Wiens, John J

2013-12-22

Many clades contain ecologically and phenotypically similar species across continents, yet the processes generating this similarity are largely unstudied, leaving fundamental questions unanswered. Is similarity in morphology and performance across assemblages caused by evolutionary convergence or by biogeographic dispersal of evolutionarily conserved ecotypes? Does convergence to new ecological conditions erase evidence of past adaptation? Here, we analyse ecology, morphology and performance in frog assemblages from three continents (Asia, Australia and South America), assessing the importance of dispersal and convergent evolution in explaining similarity across regions. We find three striking results. First, species using the same microhabitat type are highly similar in morphology and performance across both clades and continents. Second, some species on different continents owe their similarity to dispersal and evolutionary conservatism (rather than evolutionary convergence), even over vast temporal and spatial scales. Third, in one case, an ecologically specialized ancestor radiated into diverse ecotypes that have converged with those on other continents, largely erasing traces of past adaptation to their ancestral ecology. Overall, our study highlights the roles of both evolutionary conservatism and convergence in explaining similarity in species traits over large spatial and temporal scales and demonstrates a statistical framework for addressing these questions in other systems.

Morphology, ecology and phylogeny of cyanobacteria belonging to genera Nostoc and Desmonostoc in Lithuania

OpenAIRE

Špakaitė, Ina

2014-01-01

The aim of the study was to investigate the morphology, ecology and phylogeny of cyanobacteria belonging to genera Nostoc and Desmonostoc in Lithuania. The detailed research of freshwater and terrestrial Nostoc and Desmonostoc species provided new data on taxonomy, biology and ecology of these cyanobacteria and the overall diversity of algae in Lithuania. 20 Nostoc species and two intraspecific taxa, and 18 taxa to the Nostoc genus level were identified. Twelve Nostoc species and intraspecifi...

Morphological diversity in tenrecs (Afrosoricida, Tenrecidae: comparing tenrec skull diversity to their closest relatives

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Sive Finlay

2015-04-01

Full Text Available It is important to quantify patterns of morphological diversity to enhance our understanding of variation in ecological and evolutionary traits. Here, we present a quantitative analysis of morphological diversity in a family of small mammals, the tenrecs (Afrosoricida, Tenrecidae. Tenrecs are often cited as an example of an exceptionally morphologically diverse group. However, this assumption has not been tested quantitatively. We use geometric morphometric analyses of skull shape to test whether tenrecs are more morphologically diverse than their closest relatives, the golden moles (Afrosoricida, Chrysochloridae. Tenrecs occupy a wider range of ecological niches than golden moles so we predict that they will be more morphologically diverse. Contrary to our expectations, we find that tenrec skulls are only more morphologically diverse than golden moles when measured in lateral view. Furthermore, similarities among the species-rich Microgale tenrec genus appear to mask higher morphological diversity in the rest of the family. These results reveal new insights into the morphological diversity of tenrecs and highlight the importance of using quantitative methods to test qualitative assumptions about patterns of morphological diversity.

Morphology and Ecological Notes on the Larvae and Pupae of Simulium (Simulium from Korea

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Sam-Kyu Kim

2015-10-01

Full Text Available Morphological features of larvae and pupae of twelve species of Simulium (Simulium from Korea are investigated and redescribed. Detailed descriptions of immature stages of each species are provided with photographs. For the Korean members of subgenus Simulium, combinations of the following characteristics can be used to separate them from other Korean subgenera: larval abdomen without a pair of conical-shaped ventral tubercles; postgenal cleft variously shaped, viz., miter shaped, spearhead, bullet shaped or triangular; rectal papillae 3 simple lobe or compound lobes; pupal gill of 6-16 filaments; cocoon shoe, boot or slipper shaped; and head trichomes 3 pairs (1 facial+2 frontal. Habitat information and other ecological aspects of each species are provided. Updated keys to larvae and pupae of the Korean species of the subgenus Simulium are also provided to facilitate species identification. Taxonomic treatment based on external morphologies of larvae and pupae of Korean species of the subgenus Simulium are focused and included in this study. To understand their interspecific relationships, phylogenetic analyses using multiple data from molecule, morphology, and ecology are warranted in future research. Also continued exploration for new character systems is needed to establish more stable boundaries for subgenus and species delimitations.

Anatomy, functional morphology, evolutionary ecology and systematics of the invasive gastropod Cipangopaludina japonica (Viviparidae: Bellamyinae)

NARCIS (Netherlands)

Bocxlaer, Van B.; Strong, E.E.

2016-01-01

The anatomy, functional morphology and evolutionary ecology of the Viviparidae, and the subfamily Bellamyinae in particular, are incompletely known. Partly as a result, genealogical relationships within the family remain poorly understood. Because of this lack in knowledge, few informed hypotheses

Triatominae as a model of morphological plasticity under ecological pressure

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Dujardin JP

1999-01-01

Full Text Available The use of biochemical and genetic characters to explore species or population relationships has been applied to taxonomic questions since the 60s. In responding to the central question of the evolutionary history of Triatominae, i.e. their monophyletic or polyphyletic origin, two important questions arise (i to what extent is the morphologically-based classification valid for assessing phylogenetic relationships? and (ii what are the main mechanisms underlying speciation in Triatominae? Phenetic and genetic studies so far developed suggest that speciation in Triatominae may be a rapid process mainly driven by ecological factors.

Impacts of channel morphology on residues and ecological risks of polychlorinated biphenyls in water and sediment in Chahe River

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Zhen-hua Zhao

2016-10-01

Full Text Available The impacts of channel morphology on the residues and ecological risks of 14 polychlorinated biphenyl (PCB congeners in water and sediment were investigated in summer (July and autumn (September in the Chahe River, in Nanjing, China. The residual concentrations of tri-chlorobiphenyls (tri-CBs, PCB 18 and tetra-CBs (PCB 52 in water were significantly higher than those of penta-CBs to deca-CBs, and the average residual concentration of ∑PCBs (sum of 14 PCB congeners in summer was about six times higher than in autumn. However, the residues in sediment did not change significantly. Redundancy analysis (RDA indicated that channel morphology and the corresponding environmental indices had significant impacts on PCB residues and their composition profiles in water and sediment. The overflow weir and lake-type watercourse may remarkably reduce the residual concentration and ecological risks of PCBs in water. The highest reduction percentages of the residual concentration and ecological risks of ∑PCBs induced by an overflow weir were 78% and 67%, respectively, and those induced by a lake-type watercourse were 36% and 70%, respectively. The watercourses with different channel morphologies were ranked by residual ∑PCBs concentrations in the following descending order: the natural ecological watercourse, vertical concrete watercourse, and vegetation-type riprap watercourse. However, they were ranked by residual ∑PCBs concentrations in sediment in the following descending order: the vertical concrete watercourse, vegetation-type riprap watercourse, and natural ecological watercourse.

Influence of morphology and amphibious lifestyle on the feeding ecology of the mudskipper Periophthalmus argentilineatus

NARCIS (Netherlands)

Kruitwagen, G.; Nagelkerken, I.; Lugendo, B.R.; Pratap, H.B.; Wendelaar Bonga, S.E.

2007-01-01

The potential feeding advantages that are offered to the barred mudskipper Periophthalmus argentilineatus by its amphibious life-style were investigated. To this end the feeding ecology of these fish, the position they occupy in the mangrove food web and the importance of different morphological

Morphological and ecological complexity in early eukaryotic ecosystems.

Science.gov (United States)

Javaux, E J; Knoll, A H; Walter, M R

2001-07-05

Molecular phylogeny and biogeochemistry indicate that eukaryotes differentiated early in Earth history. Sequence comparisons of small-subunit ribosomal RNA genes suggest a deep evolutionary divergence of Eukarya and Archaea; C27-C29 steranes (derived from sterols synthesized by eukaryotes) and strong depletion of 13C (a biogeochemical signature of methanogenic Archaea) in 2,700 Myr old kerogens independently place a minimum age on this split. Steranes, large spheroidal microfossils, and rare macrofossils of possible eukaryotic origin occur in Palaeoproterozoic rocks. Until now, however, evidence for morphological and taxonomic diversification within the domain has generally been restricted to very late Mesoproterozoic and Neoproterozoic successions. Here we show that the cytoskeletal and ecological prerequisites for eukaryotic diversification were already established in eukaryotic microorganisms fossilized nearly 1,500 Myr ago in shales of the early Mesoproterozoic Roper Group in northern Australia.

Genetic, Ecological and Morphological Distinctness of the Blue Mussels Mytilus trossulus Gould and M. edulis L. in the White Sea.

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Marina Katolikova

Full Text Available Two blue mussel lineages of Pliocene origin, Mytilus edulis (ME and M. trossulus (MT, co-occur and hybridize in several regions on the shores of the North Atlantic. The two species were distinguished from each other by molecular methods in the 1980s, and a large amount of comparative data on them has been accumulated since that time. However, while ME and MT are now routinely distinguished by various genetic markers, they tend to be overlooked in ecological studies since morphological characters for taxonomic identification have been lacking, and no consistent habitat differences between lineages have been reported. Surveying a recently discovered area of ME and MT co-occurrence in the White Sea and employing a set of allozyme markers for identification, we address the issue whether ME and MT are true biological species with distinct ecological characteristics or just virtual genetic entities with no matching morphological and ecological identities. We find that: (1 in the White Sea, the occurrence of MT is largely concentrated in harbors, in line with observations from other subarctic regions of Europe; (2 mixed populations of ME and MT are always dominated by purebred individuals, animals classified as hybrids constituting only ca. 18%; (3 in terms of shell morphology, 80% of MT bear a distinct uninterrupted dark prismatic strip under the ligament while 97% of ME lack this character; (4 at sites of sympatry MT is more common on algal substrates while ME mostly lives directly on the bottom. This segregation by the substrate may contribute to maintaining reproductive isolation and decreasing competition between taxa. We conclude that while ME and MT are not fully reproductively isolated, they do represent clearly distinguishable biological, ecological and morphological entities in the White Sea. It remains to be documented whether the observed morphological and ecological differences are of a local character, or whether they have simply been

Ecological divergence and medial cuneiform morphology in gorillas.

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Tocheri, Matthew W; Solhan, Christyna R; Orr, Caley M; Femiani, John; Frohlich, Bruno; Groves, Colin P; Harcourt-Smith, William E; Richmond, Brian G; Shoelson, Brett; Jungers, William L

2011-02-01

Gorillas are more closely related to each other than to any other extant primate and are all terrestrial knuckle-walkers, but taxa differ along a gradient of dietary strategies and the frequency of arboreality in their behavioral repertoire. In this study, we test the hypothesis that medial cuneiform morphology falls on a morphocline in gorillas that tracks function related to hallucial abduction ability and relative frequency of arboreality. This morphocline predicts that western gorillas, being the most arboreal, should display a medial cuneiform anatomy that reflects the greatest hallucial abduction ability, followed by grauer gorillas, and then by mountain gorillas. Using a three-dimensional methodology to measure angles between articular surfaces, relative articular and nonarticular areas, and the curvatures of the hallucial articular surface, the functional predictions are partially confirmed in separating western gorillas from both eastern gorillas. Western gorillas are characterized by a more medially oriented, proportionately larger, and more mediolaterally curved hallucial facet than are eastern gorillas. These characteristics follow the predictions for a more prehensile hallux in western gorillas relative to a more stable, plantigrade hallux in eastern gorillas. The characteristics that distinguish eastern gorilla taxa from one another appear unrelated to hallucial abduction ability or frequency of arboreality. In total, this reexamination of medial cuneiform morphology suggests differentiation between eastern and western gorillas due to a longstanding ecological divergence and more recent and possibly non-adaptive differences between eastern taxa. Published by Elsevier Ltd.

Micro morphological and Chemical Approaches to Understand Changes in Ecological Functions of Metal-Impacted Soils under Various Land Uses

International Nuclear Information System (INIS)

Acosta, J.A; Martinez, S.M; Faz, A; Van Mourik, J.M; Arocena, J.M

2011-01-01

We investigated the changes in faunal activities as measures of the ecological functions of soils impacted by potentially toxic metals (PTMs) under urban, industrial, agricultural, and natural uses. Concentrations and distributions of Zn, Cd, Pb, Cu, Mn, and Fe were estimated by sequential chemical extractions, while relicts and present faunal activities were studied by micro morphological analyses. Urban and natural lands were contaminated with Pb, Cd, and Zn. Micro arthropods and fungi are observed to be active in the litter decomposition in natural, agricultural and urban lands which indicates that total concentration of PTMs in soils is not a good indicator to evaluate the limitations of PTMs to fauna activity. Metals immobilization on carbonates and Fe/Mn oxides, and fertilizations reduced the negative effects of metals on faunal activity. Micro morphological analyses showed the impacts of metal on soil ecological functions in industrial site, where the surface soils are devoid of any evidence of faunal activity; likely due to high proportion of Pb and Zn in organic components. Therefore, the impacts of metals in soil fauna activities, hence ecological functions of soils, are best evaluated by the knowledge of metal partitioning on solid phases in combination with observations of fauna activities using micro morphological techniques.

Low ecological disparity in Early Cretaceous birds

Science.gov (United States)

Mitchell, Jonathan S.; Makovicky, Peter J.

2014-01-01

Ecological divergence is thought to be coupled with evolutionary radiations, yet the strength of this coupling is unclear. When birds diversified ecologically has received much less attention than their hotly debated crown divergence time. Here, we quantify how accurately skeletal morphology can predict ecology in living and extinct birds, and show that the earliest known assemblage of birds (= pygostylians) from the Jehol Biota (≈ 125 Ma) was substantially impoverished ecologically. The Jehol avifauna has few representatives of highly preservable ecomorphs (e.g. aquatic forms) and a notable lack of ecomorphological overlap with the pterosaur assemblage (e.g. no large or aerially foraging pygostylians). Comparisons of the Jehol functional diversity with modern and subfossil avian assemblages show that taphonomic bias alone cannot explain the ecomorphological impoverishment. However, evolutionary simulations suggest that the constrained ecological diversity of the Early Cretaceous pygostylians is consistent with what is expected from a relatively young radiation. Regardless of the proximate biological explanation, the anomalously low functional diversity of the Jehol birds is evidence both for ecological vacancies in Cretaceous ecosystems, which were subsequently filled by the radiation of crown Aves, and for discordance between taxonomic richness and ecological diversity in the best-known Mesozoic ecosystem. PMID:24870044

A policy-driven large scale ecological restoration: quantifying ecosystem services changes in the Loess Plateau of China.

Science.gov (United States)

Lü, Yihe; Fu, Bojie; Feng, Xiaoming; Zeng, Yuan; Liu, Yu; Chang, Ruiying; Sun, Ge; Wu, Bingfang

2012-01-01

As one of the key tools for regulating human-ecosystem relations, environmental conservation policies can promote ecological rehabilitation across a variety of spatiotemporal scales. However, quantifying the ecological effects of such policies at the regional level is difficult. A case study was conducted at the regional level in the ecologically vulnerable region of the Loess Plateau, China, through the use of several methods including the Universal Soil Loss Equation (USLE), hydrological modeling and multivariate analysis. An assessment of the changes over the period of 2000-2008 in four key ecosystem services was undertaken to determine the effects of the Chinese government's ecological rehabilitation initiatives implemented in 1999. These ecosystem services included water regulation, soil conservation, carbon sequestration and grain production. Significant conversions of farmland to woodland and grassland were found to have resulted in enhanced soil conservation and carbon sequestration, but decreased regional water yield under a warming and drying climate trend. The total grain production increased in spite of a significant decline in farmland acreage. These trends have been attributed to the strong socioeconomic incentives embedded in the ecological rehabilitation policy. Although some positive policy results have been achieved over the last decade, large uncertainty remains regarding long-term policy effects on the sustainability of ecological rehabilitation performance and ecosystem service enhancement. To reduce such uncertainty, this study calls for an adaptive management approach to regional ecological rehabilitation policy to be adopted, with a focus on the dynamic interactions between people and their environments in a changing world.

Quantifying temporal bone morphology of great apes and humans: an approach using geometric morphometrics

Science.gov (United States)

Lockwood, Charles A; Lynch, John M; Kimbel, William H

2002-01-01

The hominid temporal bone offers a complex array of morphology that is linked to several different functional systems. Its frequent preservation in the fossil record gives the temporal bone added significance in the study of human evolution, but its morphology has proven difficult to quantify. In this study we use techniques of 3D geometric morphometrics to quantify differences among humans and great apes and discuss the results in a phylogenetic context. Twenty-three landmarks on the ectocranial surface of the temporal bone provide a high level of anatomical detail. Generalized Procrustes analysis (GPA) is used to register (adjust for position, orientation and scale) landmark data from 405 adults representing Homo, Pan, Gorilla and Pongo. Principal components analysis of residuals from the GPA shows that the major source of variation is between humans and apes. Human characteristics such as a coronally orientated petrous axis, a deep mandibular fossa, a projecting mastoid process, and reduced lateral extension of the tympanic element strongly impact the analysis. In phenetic cluster analyses, gorillas and orangutans group together with respect to chimpanzees, and all apes group together with respect to humans. Thus, the analysis contradicts depictions of African apes as a single morphotype. Gorillas and orangutans lack the extensive preglenoid surface of chimpanzees, and their mastoid processes are less medially inflected. These and other characters shared by gorillas and orangutans are probably primitive for the African hominid clade. PMID:12489757

Morphology and ecology of sibon snakes (Squamata: Dipsadidae) from two forests in Central America

OpenAIRE

Todd R. Lewis; Rowland K. Griffin; Paul B. C. Grant; Alex Figueroa; Julie M. Ray; Kirsty E. Graham; Gabriel David

2013-01-01

Physical measurements, abundance, and ecological observations were recorded for Sibon annulatus,S. argus, S. longifrens, and S. nebulatus at two Neotropical habitats: a lowland swamp forest in Costa Rica and a montane cloud forest in Panama. Fourty-four and 58 adult snakes were recorded from Costa Rica and Panama, respectively. Differences in morphology and body condition showed minimal significant differences among species from both geographical locations. Observations of feeding, reproducti...

Evolutionary dynamics of ecological niche in three Rhinogobio fishes from the upper Yangtze River inferred from morphological traits

Science.gov (United States)

Wang, Meirong; Liu, Fei; Lin, Pengcheng; Yang, Shaorong; Liu, Huanzhang

2015-01-01

In the past decades, it has been debated whether ecological niche should be conserved among closely related species (phylogenetic niche conservatism, PNC) or largely divergent (traditional ecological niche theory and ecological speciation) and whether niche specialist and generalist might remain in equilibrium or niche generalist could not appear. In this study, we employed morphological traits to describe ecological niche and test whether different niche dimensions exhibit disparate evolutionary patterns. We conducted our analysis on three Rhinogobio fish species (R. typus,R. cylindricus, and R. ventralis) from the upper Yangtze River, China. Among the 32 measured morphological traits except body length, PCA extracted the first four principal components with their loading scores >1.000. To find the PNC among species, Mantel tests were conducted with the Euclidean distances calculated from the four principal components (representing different niche dimensions) against the pairwise distances calculated from mitochondrial cytochrome b sequence variations. The results showed that the second and the third niche dimension, both related to swimming ability and behavior, exhibited phylogenetic conservatism. Further comparison on niche breadth among these three species revealed that the fourth dimension of R. typus showed the greatest width, indicating that this dimension exhibited niche generalism. In conclusion, our results suggested that different niche dimensions could show different evolutionary dynamic patterns: they may exhibit PNC or not, and some dimensions may evolve generalism. PMID:25691981

Bedform morphology of salmon spawning areas in a large gravel-bed river

Energy Technology Data Exchange (ETDEWEB)

Hanrahan, Timothy P.

2007-05-01

While the importance of river channel morphology to salmon spawning habitat is increasingly recognized, quantitative measures of the relationships between channel morphology and habitat use are lacking. Such quantitative measures are necessary as management and regulatory agencies within the Pacific Northwestern region of the USA, and elsewhere, seek to quantify potential spawning habitat and develop recovery goals for declining salmon populations. The objective of this study was to determine if fall Chinook salmon (Oncorhynchus tshawytscha) spawning areas in the Snake River, Idaho, USA, were correlated with specific bed form types at the pool-riffle scale. A bed form differencing technique was used to objectively quantify the longitudinal riverbed profile into four distinct pool-riffle units that were independent of discharge. The vertical location of thalweg points within these units was quantified with a riffle proximity index. Chinook salmon spawning areas were mapped and correlated with the pool-riffle units through the use of cross-tabulation tables. The results indicate that 84% of fall Chinook salmon spawning areas were correlated with riffles (Chi-square=152.1, df=3, p<0.001), with 53% of those areas located on the upstream side of riffle crests. The majority of Snake River fall Chinook salmon spawning occurred at a vertical location within 80% of the nearest riffle crest elevation. The analyses of bed form morphology will assist regional fish mangers in quantifying existing and potential fall Chinook salmon spawning habitat, and will provide a quantitative framework for evaluating general ecological implications of channel morphology in large gravel-bed rivers.

Morphology captures diet and locomotor types in rodents.

Science.gov (United States)

Verde Arregoitia, Luis D; Fisher, Diana O; Schweizer, Manuel

2017-01-01

To understand the functional meaning of morphological features, we need to relate what we know about morphology and ecology in a meaningful, quantitative framework. Closely related species usually share more phenotypic features than distant ones, but close relatives do not necessarily have the same ecologies. Rodents are the most diverse group of living mammals, with impressive ecomorphological diversification. We used museum collections and ecological literature to gather data on morphology, diet and locomotion for 208 species of rodents from different bioregions to investigate how morphological similarity and phylogenetic relatedness are associated with ecology. After considering differences in body size and shared evolutionary history, we find that unrelated species with similar ecologies can be characterized by a well-defined suite of morphological features. Our results validate the hypothesized ecological relevance of the chosen traits. These cranial, dental and external (e.g. ears) characters predicted diet and locomotion and showed consistent differences among species with different feeding and substrate use strategies. We conclude that when ecological characters do not show strong phylogenetic patterns, we cannot simply assume that close relatives are ecologically similar. Museum specimens are valuable records of species' phenotypes and with the characters proposed here, morphology can reflect functional similarity, an important component of community ecology and macroevolution.

Process-morphology scaling relations quantify self-organization in capillary densified nanofiber arrays.

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Kaiser, Ashley L; Stein, Itai Y; Cui, Kehang; Wardle, Brian L

2018-02-07

Capillary-mediated densification is an inexpensive and versatile approach to tune the application-specific properties and packing morphology of bulk nanofiber (NF) arrays, such as aligned carbon nanotubes. While NF length governs elasto-capillary self-assembly, the geometry of cellular patterns formed by capillary densified NFs cannot be precisely predicted by existing theories. This originates from the recently quantified orders of magnitude lower than expected NF array effective axial elastic modulus (E), and here we show via parametric experimentation and modeling that E determines the width, area, and wall thickness of the resulting cellular pattern. Both experiments and models show that further tuning of the cellular pattern is possible by altering the NF-substrate adhesion strength, which could enable the broad use of this facile approach to predictably pattern NF arrays for high value applications.

Quantifying Ecology: Constructing Life History Tables

Science.gov (United States)

Balgopal, Meena M.; Ode, Paul J.

2009-01-01

In the biology community there has been a call for integrating lessons on population growth rate and the human population crisis into biology classrooms. Ecologists fear that students do not understand the relationship between the magnitude of the human population growth and Earth's carrying capacity, as well as some basic ecological concepts. The…

Two-dimensional hydrodynamic modeling to quantify effects of peak-flow management on channel morphology and salmon-spawning habitat in the Cedar River, Washington

Science.gov (United States)

Czuba, Christiana; Czuba, Jonathan A.; Gendaszek, Andrew S.; Magirl, Christopher S.

2010-01-01

The Cedar River in Washington State originates on the western slope of the Cascade Range and provides the City of Seattle with most of its drinking water, while also supporting a productive salmon habitat. Water-resource managers require detailed information on how best to manage high-flow releases from Chester Morse Lake, a large reservoir on the Cedar River, during periods of heavy precipitation to minimize flooding, while mitigating negative effects on fish populations. Instream flow-management practices include provisions for adaptive management to promote and maintain healthy aquatic habitat in the river system. The current study is designed to understand the linkages between peak flow characteristics, geomorphic processes, riverine habitat, and biological responses. Specifically, two-dimensional hydrodynamic modeling is used to simulate and quantify the effects of the peak-flow magnitude, duration, and frequency on the channel morphology and salmon-spawning habitat. Two study reaches, representative of the typical geomorphic and ecologic characteristics of the Cedar River, were selected for the modeling. Detailed bathymetric data, collected with a real-time kinematic global positioning system and an acoustic Doppler current profiler, were combined with a LiDAR-derived digital elevation model in the overbank area to develop a computational mesh. The model is used to simulate water velocity, benthic shear stress, flood inundation, and morphologic changes in the gravel-bedded river under the current and alternative flood-release strategies. Simulations of morphologic change and salmon-redd scour by floods of differing magnitude and duration enable water-resource managers to incorporate model simulation results into adaptive management of peak flows in the Cedar River. PDF version of a presentation on hydrodynamic modelling in the Cedar River in Washington state. Presented at the American Geophysical Union Fall Meeting 2010.

Morphology and ecology of Daphnia middendorffiana, Fisher 1851 (Crustacea, Daphniidae from four new populations in the Alps

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Rocco TIBERTI

2011-08-01

Full Text Available Daphnia middendorffiana has an arctic, circumpolar distribution, with some isolated southerly populations restricted to mountainous areas, including the Alps. In this paper, new records of Daphnia middendorffiana on the Alps are reported. The species was regularly recorded in several samples collected from 2006 to 2009 in four high altitude lakes in the Gran Paradiso National Park (GPNP during the ice free period. This is the third finding for the Alps and the described populations are the largest. Chemical and morphometric features of the lakes are provided, the morphology of the Daphnia middendorffiana from GPNP is described as well as some aspects concerning its ecology. The studied lakes are small, oligotrophic (total phosphorus ranged from 0 to 7 μg L-1 and well preserved from acidification risk (pH ranged from 6.45 to 8.14. D. middendorffiana is the largest zooplanktonic crustacean inhabiting the Alpine lakes in GPNP reaching 3.43 mm in length; the morphological analysis noted some differences within the studied populations; however there is a clear resemblance to the only Alpine population previously described (from Central Alps, Bognanco Valley, Lake Campo IV and to the arctic populations. D. middendorffiana in GPNP lives at low density levels, reaching higher densities in late August and early September. No males have been found during the sample campaign confirming its ability to produce asexual viable diapauses eggs. This study confirms the attitude of this species for cold and oligotrophic waters and increases the current knowledge on the geographical distribution, morphology and ecology of this species in Alpine environments. The finding of D. middendordorffiana in the GPNP poses interesting issues concerning the phylogeography of Alpine Daphnia middendorffiana, as well as raising need for conservation efforts aimed at keeping the populations safe from several global and local threats, such as climate warming and the ecological

A three-dimensional morphometric analysis of upper forelimb morphology in the enigmatic tapir (Perissodactyla: Tapirus) hints at subtle variations in locomotor ecology.

Science.gov (United States)

MacLaren, Jamie A; Nauwelaerts, Sandra

2016-11-01

Forelimb morphology is an indicator for terrestrial locomotor ecology. The limb morphology of the enigmatic tapir (Perissodactyla: Tapirus) has often been compared to that of basal perissodactyls, despite the lack of quantitative studies comparing forelimb variation in modern tapirs. Here, we present a quantitative assessment of tapir upper forelimb osteology using three-dimensional geometric morphometrics to test whether the four modern tapir species are monomorphic in their forelimb skeleton. The shape of the upper forelimb bones across four species (T. indicus; T. bairdii; T. terrestris; T. pinchaque) was investigated. Bones were laser scanned to capture surface morphology and 3D landmark analysis was used to quantify shape. Discriminant function analyses were performed to reveal features which could be used for interspecific discrimination. Overall our results show that the appendicular skeleton contains notable interspecific differences. We demonstrate that upper forelimb bones can be used to discriminate between species (>91% accuracy), with the scapula proving the most diagnostic bone (100% accuracy). Features that most successfully discriminate between the four species include the placement of the cranial angle of the scapula, depth of the humeral condyle, and the caudal deflection of the olecranon. Previous studies comparing the limbs of T. indicus and T. terrestris are corroborated by our quantitative findings. Moreover, the mountain tapir T. pinchaque consistently exhibited the greatest divergence in morphology from the other three species. Despite previous studies describing tapirs as functionally mediportal in their locomotor style, we find osteological evidence suggesting a spectrum of locomotor adaptations in the tapirs. We conclude that modern tapir forelimbs are neither monomorphic nor are tapirs as conserved in their locomotor habits as previously described. J. Morphol. 277:1469-1485, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals

Ecological niche modelling and nDNA sequencing support a new, morphologically cryptic beetle species unveiled by DNA barcoding.

Science.gov (United States)

Hawlitschek, Oliver; Porch, Nick; Hendrich, Lars; Balke, Michael

2011-02-09

DNA sequencing techniques used to estimate biodiversity, such as DNA barcoding, may reveal cryptic species. However, disagreements between barcoding and morphological data have already led to controversy. Species delimitation should therefore not be based on mtDNA alone. Here, we explore the use of nDNA and bioclimatic modelling in a new species of aquatic beetle revealed by mtDNA sequence data. The aquatic beetle fauna of Australia is characterised by high degrees of endemism, including local radiations such as the genus Antiporus. Antiporus femoralis was previously considered to exist in two disjunct, but morphologically indistinguishable populations in south-western and south-eastern Australia. We constructed a phylogeny of Antiporus and detected a deep split between these populations. Diagnostic characters from the highly variable nuclear protein encoding arginine kinase gene confirmed the presence of two isolated populations. We then used ecological niche modelling to examine the climatic niche characteristics of the two populations. All results support the status of the two populations as distinct species. We describe the south-western species as Antiporus occidentalis sp.n. In addition to nDNA sequence data and extended use of mitochondrial sequences, ecological niche modelling has great potential for delineating morphologically cryptic species.

Morphological, hydrological, biogeochemical and ecological changes and challenges in river restoration - the Thur River case study

Science.gov (United States)

Schirmer, M.; Luster, J.; Linde, N.; Perona, P.; Mitchell, E. A. D.; Barry, D. A.; Hollender, J.; Cirpka, O. A.; Schneider, P.; Vogt, T.; Radny, D.; Durisch-Kaiser, E.

2014-06-01

River restoration can enhance river dynamics, environmental heterogeneity and biodiversity, but the underlying processes governing the dynamic changes need to be understood to ensure that restoration projects meet their goals, and adverse effects are prevented. In particular, we need to comprehend how hydromorphological variability quantitatively relates to ecosystem functioning and services, biodiversity as well as ground- and surface water quality in restored river corridors. This involves (i) physical processes and structural properties, determining erosion and sedimentation, as well as solute and heat transport behavior in surface water and within the subsurface; (ii) biogeochemical processes and characteristics, including the turnover of nutrients and natural water constituents; and (iii) ecological processes and indicators related to biodiversity and ecological functioning. All these aspects are interlinked, requiring an interdisciplinary investigation approach. Here, we present an overview of the recently completed RECORD (REstored CORridor Dynamics) project in which we combined physical, chemical, and biological observations with modeling at a restored river corridor of the perialpine Thur River in Switzerland. Our results show that river restoration, beyond inducing morphologic changes that reshape the river bed and banks, triggered complex spatial patterns of bank infiltration, and affected habitat type, biotic communities and biogeochemical processes. We adopted an interdisciplinary approach of monitoring the continuing changes due to restoration measures to address the following questions: How stable is the morphological variability established by restoration? Does morphological variability guarantee an improvement in biodiversity? How does morphological variability affect biogeochemical transformations in the river corridor? What are some potential adverse effects of river restoration? How is river restoration influenced by catchment-scale hydraulics

Morphology and ecology of sibon snakes (Squamata: Dipsadidae from two forests in Central America

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Todd R. Lewis

2013-06-01

Full Text Available Physical measurements, abundance, and ecological observations were recorded for Sibon annulatus,S. argus, S. longifrens, and S. nebulatus at two Neotropical habitats: a lowland swamp forest in Costa Rica and a montane cloud forest in Panama. Fourty-four and 58 adult snakes were recorded from Costa Rica and Panama, respectively. Differences in morphology and body condition showed minimal significant differences among species from both geographical locations. Observations of feeding, reproduction, abundance, distribution and a new size record for S. annulatus are discussed.

Blind to morphology: Genetics identifies several widespread ecologically common species and few endemics among Indo-Pacific cauliflower corals (Pocillopora, Scleractinia)

KAUST Repository

Pinzón, Jorge H C

2013-04-05

Aim: Using high-resolution genetic markers on samples gathered from across their wide distributional range, we endeavoured to delimit species diversity in reef-building Pocillopora corals. They are common, ecologically important, and widespread throughout the Indo-Pacific, but their phenotypic plasticity in response to environmental conditions and their nearly featureless microskeletal structures confound taxonomic assignments and limit an understanding of their ecology and evolution. Location: Indo-Pacific, Red Sea, Arabian/Persian Gulf. Methods: Sequence analysis of nuclear ribosomal (internal transcribed spacer 2, ITS2) and mitochondrial (open reading frame) loci were combined with population genetic data (seven microsatellite loci) for Pocillopora samples collected throughout the Indo-Pacific, Red Sea and Arabian Gulf, in order to assess the evolutionary divergence, reproductive isolation, frequency of hybridization and geographical distributions of the genus. Results: Between five and eight genetically distinct lineages comparable to species were identified with minimal or no hybridization between them. Colony morphology was generally incongruent with genetics across the full range of sampling, and the total number of species is apparently consistent with lower estimates from competing morphologically based hypotheses (about seven or eight taxa). The most commonly occurring genetic lineages were widely distributed and exhibited high dispersal and gene flow, factors that have probably minimized allopatric speciation. Uniquely among scleractinian genera, this genus contains a monophyletic group of broadcast spawners that evolved recently from an ancestral brooder. Main conclusions: The delineation of species diversity guided by genetics fundamentally advances our understanding of Pocillopora geographical distributions, ecology and evolution. Because traditional diagnostic features of colony and branch morphology are proving to be of limited utility, the

Blind to morphology: Genetics identifies several widespread ecologically common species and few endemics among Indo-Pacific cauliflower corals (Pocillopora, Scleractinia)

KAUST Repository

Pinzó n, Jorge H C; Sampayo, Eugenia M.; Cox, Evelyn F.; Chauka, Leonard J.; Chen, Chaolun Allen; Voolstra, Christian R.; LaJeunesse, Todd C.

2013-01-01

Aim: Using high-resolution genetic markers on samples gathered from across their wide distributional range, we endeavoured to delimit species diversity in reef-building Pocillopora corals. They are common, ecologically important, and widespread throughout the Indo-Pacific, but their phenotypic plasticity in response to environmental conditions and their nearly featureless microskeletal structures confound taxonomic assignments and limit an understanding of their ecology and evolution. Location: Indo-Pacific, Red Sea, Arabian/Persian Gulf. Methods: Sequence analysis of nuclear ribosomal (internal transcribed spacer 2, ITS2) and mitochondrial (open reading frame) loci were combined with population genetic data (seven microsatellite loci) for Pocillopora samples collected throughout the Indo-Pacific, Red Sea and Arabian Gulf, in order to assess the evolutionary divergence, reproductive isolation, frequency of hybridization and geographical distributions of the genus. Results: Between five and eight genetically distinct lineages comparable to species were identified with minimal or no hybridization between them. Colony morphology was generally incongruent with genetics across the full range of sampling, and the total number of species is apparently consistent with lower estimates from competing morphologically based hypotheses (about seven or eight taxa). The most commonly occurring genetic lineages were widely distributed and exhibited high dispersal and gene flow, factors that have probably minimized allopatric speciation. Uniquely among scleractinian genera, this genus contains a monophyletic group of broadcast spawners that evolved recently from an ancestral brooder. Main conclusions: The delineation of species diversity guided by genetics fundamentally advances our understanding of Pocillopora geographical distributions, ecology and evolution. Because traditional diagnostic features of colony and branch morphology are proving to be of limited utility, the

Morphological and ecological preadaptations as the basis of bird synanthropization under transformed environment conditions

Science.gov (United States)

Rakhimov, I. I.; Ibragimova, K. K.

2018-01-01

Bird synanthropization is connected with a thorough and serious reconstruction of their biology and is a demonstration of changes currently occurring in the biosphere due to human influence. Nutritional and nesting conditions as well as protection due to urban characteristics are advantage factors that affect their populations. Under these conditions, the adaptive potential of species can be realized. Adaptations to a new and in-distinctive environment appear due to preadaptations. The synanthropization process of species happens without speciation by expression of existing genetic variation of morphological and ecological characteristics.

Identification of major and minor QTL for ecologically important morphological traits in three-spined sticklebacks (Gasterosteus aculeatus).

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Liu, Jun; Shikano, Takahito; Leinonen, Tuomas; Cano, José Manuel; Li, Meng-Hua; Merilä, Juha

2014-04-16

Quantitative trait locus (QTL) mapping studies of Pacific three-spined sticklebacks (Gasterosteus aculeatus) have uncovered several genomic regions controlling variability in different morphological traits, but QTL studies of Atlantic sticklebacks are lacking. We mapped QTL for 40 morphological traits, including body size, body shape, and body armor, in a F2 full-sib cross between northern European marine and freshwater three-spined sticklebacks. A total of 52 significant QTL were identified at the 5% genome-wide level. One major QTL explaining 74.4% of the total variance in lateral plate number was detected on LG4, whereas several major QTL for centroid size (a proxy for body size), and the lengths of two dorsal spines, pelvic spine, and pelvic girdle were mapped on LG21 with the explained variance ranging from 27.9% to 57.6%. Major QTL for landmark coordinates defining body shape variation also were identified on LG21, with each explaining ≥15% of variance in body shape. Multiple QTL for different traits mapped on LG21 overlapped each other, implying pleiotropy and/or tight linkage. Thus, apart from providing confirmatory data to support conclusions born out of earlier QTL studies of Pacific sticklebacks, this study also describes several novel QTL of both major and smaller effect for ecologically important traits. The finding that many major QTL mapped on LG21 suggests that this linkage group might be a hotspot for genetic determinants of ecologically important morphological traits in three-spined sticklebacks.

Estimating the magnitude of morphoscapes: how to measure the morphological component of biodiversity in relation to habitats using geometric morphometrics

Science.gov (United States)

Fontaneto, Diego; Panisi, Martina; Mandrioli, Mauro; Montardi, Dario; Pavesi, Maurizio; Cardini, Andrea

2017-08-01

Ecological indicators are currently developed to account for the different facets of loss of biological diversity due to direct or indirect effects of human activities. Most ecological indicators include species richness as a metric. Others, such as functional traits and phylogenetic diversity, account for differences in species, even when species richness is the same. Here, we describe and apply a different indicator, called morphoscape dimension, accounting for morphological variability across habitats in a geographical region. We use the case of ground beetles (Coleoptera: Carabidae) in four different habitats in the Po Plain in Northern Italy to exemplify how to quantify the magnitude of the morphological space (i.e. the dimension of the morphoscape) occupied by the species in each habitat using geometric morphometrics. To this aim, we employed a variety of metrics of morphological disparity related to univariate size, and more complex multivariate shape and form. Our `proof of concept' suggests that metrics assessing size and form might largely tend to simply mirror the information provided by species richness, whereas shape morphoscape disparity may be able to account for non-trivial differences in species traits amongst habitats. This is indicated by the woodland morphoscape being on average bigger than that of crops, the most species-rich habitat, despite having almost 20% less species. We conclude suggesting that the analysis of morphoscape dimension has the potential to become a new additional and complimentary tool in the hands of conservation biologists and ecologists to explore and quantify habitat complexity and inform decisions on management and conservation based on a wide set of ecological indicators.

A Framework to Quantify the Strength of the Ecological Links ...

Science.gov (United States)

Anthropogenic stressors such as climate change, fire, and pollution are driving shifts in ecosystem function and resilience. Scientists generally rely on biological indicators of these stressors to signal that ecosystem conditions have been altered beyond an acceptable amount. However, these biological indicators are not always capable of being directly related to ecosystem services that allow scientists to communicate the importance of the change to land managers and policy makers. Therefore, we developed the STEPS (STressor – Ecological Production function – final ecosystem goods and Services) Framework to link changes in a biological indicator of a stressor to Final Ecosystem Goods and Services (FEGS). The STEPS framework produces “chains” of ecological components that connect the change in a biological indicator to the Final Ecosystem Goods and Services Classification System (FEGS-CS). The series of ecological components is an ecological production functions (EPF) which links a biological indicator of a stressor to an ecological endpoint (i.e., FEGS) that is directly used, appreciated, or valued by humans. The framework uses a qualitative score (High, Medium, Low) for the Strength of Science (SOS) for the relationship between each of the components in the EPF to identify research gaps and prioritize decision making based on what research has been completed. The ecological endpoint of the EPF is a FEGS to which discrete Beneficiaries, or direct users

Studies on geo-morphology, ecology and fish production of the 92 rivers of Rajshahi Division, Bangladesh

OpenAIRE

Rahman, M.K.; Akhter, J.N.; Nima, A.; Ahmed, S.U.; Mazid, M.A.

2003-01-01

Geo-morphology, ecology and fish production of the 92 rivers of Rajshahi division have been presented in this paper. Fifteen rivers are dead and 11 rivers have severe erosion problem. Siltation has increased in 66 rivers and depth has decreased in 11 rivers. Sixty nine rivers are suffering from low flow conditions. Fish diversity has decreased in 20 rivers while fish production has declined in 75 rivers. A total of 31 fish species have extinct, 25 species are under threat of extinction and 43...

New data on distribution, morphology and ecology of Oedogonium capillare Kützing ex Hirn (Oedogoniales, Chlorophyta in Poland

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Marta Pikosz

2015-12-01

Full Text Available Algological investigations were focused on taxonomy, chorology and ecology of threatened filamentous green alga species in Poland. Studies on Oedogonium capillare Kützing ex Hirn growing in large quantities in association with Cladophora rivularis (Linnaeus Hoek in pond were conducted. The aim of these studies was to describe the distribution, ecology and morphology of O. capillare as part of a more comprehensive study of this filamentous green alga. It is the eighth record in Poland for O. capillare. Filaments of O. capillare were grown over a wide pH range (7.3-9.6 and in high variability of nutrients. Vegetative cells, oogonia and antheridia were observed, which allowed taxonomic identification. O. capillare occurs in eutrophic waters which requires protection of its habitat.

Drag forces of common plant species in temperate streams: consequences of morphology, velocity and biomass

DEFF Research Database (Denmark)

Jensen, Kaj Sand

2008-01-01

Swift flow in streams may physically influence the morphology and distribution of plants. I quantified drag as a function of velocity, biomass and their interaction on the trailing canopy of seven European stream species in an experimental flume and evaluated its importance for species distributi...... than an uneven distribution with the same biomass confined to dense patches surrounded by open flow channels. Thus, management strategies to ensure a patchy plants distribution should be suitable for combining agricultural drainage and ecological stream quality....

Functional constraints on tooth morphology in carnivorous mammals

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Smits Peter D

2012-08-01

Full Text Available Abstract Background The range of potential morphologies resulting from evolution is limited by complex interacting processes, ranging from development to function. Quantifying these interactions is important for understanding adaptation and convergent evolution. Using three-dimensional reconstructions of carnivoran and dasyuromorph tooth rows, we compared statistical models of the relationship between tooth row shape and the opposing tooth row, a static feature, as well as measures of mandibular motion during chewing (occlusion, which are kinetic features. This is a new approach to quantifying functional integration because we use measures of movement and displacement, such as the amount the mandible translates laterally during occlusion, as opposed to conventional morphological measures, such as mandible length and geometric landmarks. By sampling two distantly related groups of ecologically similar mammals, we study carnivorous mammals in general rather than a specific group of mammals. Results Statistical model comparisons demonstrate that the best performing models always include some measure of mandibular motion, indicating that functional and statistical models of tooth shape as purely a function of the opposing tooth row are too simple and that increased model complexity provides a better understanding of tooth form. The predictors of the best performing models always included the opposing tooth row shape and a relative linear measure of mandibular motion. Conclusions Our results provide quantitative support of long-standing hypotheses of tooth row shape as being influenced by mandibular motion in addition to the opposing tooth row. Additionally, this study illustrates the utility and necessity of including kinetic features in analyses of morphological integration.

Managing for No Net Loss of Ecological Services: An Approach for Quantifying Loss of Coastal Wetlands due to Sea Level Rise.

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Kassakian, Jennifer; Jones, Ann; Martinich, Jeremy; Hudgens, Daniel

2017-05-01

Sea level rise has the potential to substantially alter the extent and nature of coastal wetlands and the critical ecological services they provide. In making choices about how to respond to rising sea level, planners are challenged with weighing easily quantified risks (e.g., loss of property value due to inundation) against those that are more difficult to quantify (e.g., loss of primary production or carbon sequestration services provided by wetlands due to inundation). Our goal was to develop a cost-effective, appropriately-scaled, model-based approach that allows planners to predict, under various sea level rise and response scenarios, the economic cost of wetland loss-with the estimates proxied by the costs of future restoration required to maintain the existing level of wetland habitat services. Our approach applies the Sea Level Affecting Marshes Model to predict changes in wetland habitats over the next century, and then applies Habitat Equivalency Analysis to predict the cost of restoration projects required to maintain ecological services at their present, pre-sea level rise level. We demonstrate the application of this approach in the Delaware Bay estuary and in the Indian River Lagoon (Florida), and discuss how this approach can support future coastal decision-making.

Trophic specialization drives morphological evolution in sea snakes.

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Sherratt, Emma; Rasmussen, Arne R; Sanders, Kate L

2018-03-01

Viviparous sea snakes are the most rapidly speciating reptiles known, yet the ecological factors underlying this radiation are poorly understood. Here, we reconstructed dated trees for 75% of sea snake species and quantified body shape (forebody relative to hindbody girth), maximum body length and trophic diversity to examine how dietary specialization has influenced morphological diversification in this rapid radiation. We show that sea snake body shape and size are strongly correlated with the proportion of burrowing prey in the diet. Specialist predators of burrowing eels have convergently evolved a 'microcephalic' morphotype with dramatically reduced forebody relative to hindbody girth and intermediate body length. By comparison, snakes that predominantly feed on burrowing gobies are generally short-bodied and small-headed, but there is no evidence of convergent evolution. The eel specialists also exhibit faster rates of size and shape evolution compared to all other sea snakes, including those that feed on gobies. Our results suggest that trophic specialization to particular burrowing prey (eels) has invoked strong selective pressures that manifest as predictable and rapid morphological changes. Further studies are needed to examine the genetic and developmental mechanisms underlying these dramatic morphological changes and assess their role in sea snake speciation.

Does the Morphology of the Forelimb Flexor Muscles Differ Between Lizards Using Different Habitats?

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Lowie, Aurélien; Herrel, Anthony; Abdala, Virginia; Manzano, Adriana S; Fabre, Anne-Claire

2018-03-01

Lizards are an interesting group to study how habitat use impacts the morphology of the forelimb because they occupy a great diversity of ecological niches. In this study, we specifically investigated whether habitat use impacts the morphology of the forelimb flexor muscles in lizards. To do so, we performed dissections and quantified the physiological cross sectional area (PCSA), the fiber length, and the mass of four flexor muscles in 21 different species of lizards. Our results show that only the PCSA of the m. flexor carpi radialis is different among lizards with different ecologies (arboreal versus non-arboreal). This difference disappeared, however, when taking phylogeny into account. Arboreal species have a higher m. flexor carpi radialis cross sectional area likely allowing them to flex the wrist more forcefully which may allow them climb and hold on to branches better. In contrast, other muscles are not different between arboreal and non-arboreal species. Further studies focusing on additional anatomical features of the lizard forelimb as well as studies documenting how lizards use the arboreal niche are needed to fully understand how an arboreal life style may constrain limb morphology in lizards. Anat Rec, 301:424-433, 2018. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

The chimpanzee nest quantified: morphology and ecology of arboreal sleeping platforms within the dry habitat site of Toro-Semliki Wildlife Reserve, Uganda.

Science.gov (United States)

Samson, David R

2012-10-01

The nightly construction of a sleeping platform (SP) or "nest" is widely regarded as a universal behavior among great apes, yet SP structural morphology has been incompletely quantified to date. This is in part due to the inherent difficulties of gathering empirical data on arboreally sited SPs. I gathered quantitative structural data on SPs (n = 65) at the Toro-Semliki Wildlife Reserve from May to June 2008 and from August 2010 to January 2011. I measured SP length (semi-major axis length), width (semi-minor axis length), radii (length from the surface center to the rim edge 45° from the axis), depth (width of the concavity from the surface center to the parallel rim), and thickness (ventral center to the dorsal underside of the SP). SP complexity was defined with a scored index. SP complexity was found to be correlated with SP circumference, surface area, mass, proportion of soft leafy material to hard woody material, number of frame support branches used in its construction, and other measures that are argued to index "comfort." In addition, the height of the tree canopy above the SP was negatively correlated with SP complexity. Greater complexity (and therefore stability) is argued to maintain SP integrity, stability and restraint in the face of greater wind speeds, thereby reducing the probability of falls. Given the observation that males site SPs lower than females (Fruth and Hohmann, Ethology 94:113-126, 1994; Brownlow et al., Am J Primatol 55:49-55, 2001), and that SP diameters were greater for SPs sited low in the canopy at Semliki, it is inferred that more massive males benefit from lower climbing expenses and greater stability. These data support Baldwin and colleagues' (Primates 22:474-486, 1981) hypothesis that the principal advantage of SPs over open-branch sleeping sites is the greater stability required by large-bodied great apes.

Quantifying Risk in Epidemiological and Ecological Contexts

OpenAIRE

Sellman, Stefan

2018-01-01

The rates of globalization and growth of the human population puts ever increasing pressure on the agricultural sector to intensify and grow more complex, and with this intensification comes an increased risk of outbreaks of infectious livestock diseases. At the same time, and for the same reasons, the detrimental effect that humans have on other species with which we share the environment has never been more apparent, as the current rates of species loss from ecological communities rival tho...

What is dental ecology?

Science.gov (United States)

Cuozzo, Frank P; Sauther, Michelle L

2012-06-01

Teeth have long been used as indicators of primate ecology. Early work focused on the links between dental morphology, diet, and behavior, with more recent years emphasizing dental wear, microstructure, development, and biogeochemistry, to understand primate ecology. Our study of Lemur catta at the Beza Mahafaly Special Reserve, Madagascar, has revealed an unusual pattern of severe tooth wear and frequent tooth loss, primarily the result of consuming a fallback food for which these primates are not dentally adapted. Interpreting these data was only possible by combining our areas of expertise (dental anatomy [FC] and primate ecology [MS]). By integrating theoretical, methodological, and applied aspects of both areas of research, we adopted the term "dental ecology"-defined as the broad study of how teeth respond to the environment. Specifically, we view dental ecology as an interpretive framework using teeth as a vehicle for understanding an organism's ecology, which builds upon earlier work, but creates a new synthesis of anatomy and ecology that is only possible with detailed knowledge of living primates. This framework includes (1) identifying patterns of dental pathology and tooth use-wear, within the context of feeding ecology, behavior, habitat variation, and anthropogenic change, (2) assessing ways in which dental development and biogeochemical signals can reflect habitat, environmental change and/or stress, and (3) how dental microstructure and macro-morphology are adapted to, and reflect feeding ecology. Here we define dental ecology, provide a short summary of the development of this perspective, and place our new work into this context. Copyright © 2012 Wiley Periodicals, Inc.

Quantifying Forest Ecosystem Services Tradeoff—Coupled Ecological and Economic Models

Science.gov (United States)

Haff, P. K.; Ling, P. Y.

2015-12-01

Quantification of the effect of carbon-related forestland management activities on ecosystem services is difficult, because knowledge about the dynamics of coupled social-ecological systems is lacking. Different forestland management activities, such as various amount, timing, and methods of harvesting, and natural disturbances events, such as wind and fires, create shocks and uncertainties to the forest carbon dynamics. A spatially explicit model, Landis-ii, was used to model the forest succession for different harvest management scenarios at the Grandfather District, North Carolina. In addition to harvest, the model takes into account of the impact of natural disturbances, such as fire and insects, and species competition. The result shows the storage of carbon in standing biomass and in wood product for each species for each scenario. In this study, optimization is used to analyze the maximum profit and the number of tree species that each forest landowner can gain at different prices of carbon, roundwood, and interest rates for different harvest management scenarios. Time series of roundwood production of different types were estimated using remote sensing data. Econometric analysis is done to understand the possible interaction and relations between the production of different types of roundwood and roundwood prices, which can indicate the possible planting scheme that a forest owner may make. This study quantifies the tradeoffs between carbon sequestration, roundwood production, and forest species diversity not only from an economic perspective, but also takes into account of the forest succession mechanism in a species-diverse region. The resulting economic impact on the forest landowners is likely to influence their future planting decision, which in turn, will influence the species composition and future revenue of the landowners.

Cranial morphological variation in Peromyscus maniculatus over nearly a century of environmental change in three areas of California.

Science.gov (United States)

Holmes, Michael W; Boykins, Genevieve K R; Bowie, Rauri C K; Lacey, Eileen A

2016-01-01

Determining how species respond to prolonged environmental change is critical to understanding both their evolutionary biology and their conservation needs. In general, organisms can respond to changing environmental conditions by moving, by adapting in situ, or by going locally or globally extinct. Morphological changes, whether plastic or adaptive, are one way that species may respond in situ to local environmental change. Because cranial morphology is influenced by selective pressures arising from an organism's abiotic and biotic environments, including aspects of thermal physiology, diet, and sensory ecology, studies of cranial morphology may generate important insights into how species are responding to environmental change. To assess potential response of deer mice (Peromyscus maniculatus) to changing conditions in the Sierra Nevada Mountains of California, we quantified cranial variation in museum specimens of this species collected approximately 100 years apart. Specifically, we examined how cranial morphology varies in three populations of this geographically widespread, ecological generalist over elevation and time. Our analyses indicate that cranial morphology does not differ with elevation within either modern or historical samples but does vary between time periods, suggesting that in situ responses to environmental change have occurred. Contrary to predictions based on Bergmann's rule, we found no consistent relationship between body size and either elevation or time, suggesting that morphological differences detected between historic and modern specimens are specific to factors influencing cranial structure. Collectively, these analyses demonstrate the potential importance of in situ changes in morphology as a response to changing environmental conditions. © 2015 Wiley Periodicals, Inc.

Worker morphology of the ant Gnamptogenys striatula Mayr (Formicidae, Ectatomminae in different landscapes from the Atlantic Forest domain

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Roseli F. Oliveira

2015-03-01

Full Text Available Morphological traits, such as size and shape, may reflect a combination of ecological and evolutionary responses by organisms. Ants have been used to evaluate the relationship between the environment and species coexistence and morphology. In the present study, we analyzed the morphology of workers of Gnamptogenys striatula Mayr in different landscapes from the Atlantic Domain in southeastern Brazil, focusing on the variation in the morphological attributes of these populations compared to those from a dense ombrophilous forest. Eighteen morphological traits of functional importance for interactions between workers and the environment were measured to characterize the size and shape of the workers. In general, the results show that ants of urban areas possess some morphological attributes of smaller size, with highly overlapped morphological space between the populations in forested ecosystems. Further, some of the traits related to predation were relatively smaller in modified land areas than in the populations from preserved areas of dense ombrophilous forest. These results help broaden the knowledge regarding morphological diversity in G. striatula, suggesting that the characterization of the morphology may be important to quantify the effects of land use on morphological diversity, and presumably, to facilitate the use of ants as biological indicators.

Aspects of the morphology and the ecology of a Paradiplozoon species from Barbus aeneus in the Vaal Dam, South Africa

OpenAIRE

2014-01-01

M.Sc. Zoology Only a few species of the family Diplozoidae have previously been described from Africa, from various Labeo and Barbus species. An investigation was undertaken respectively in the Vaal Dam and Vaal River Barrage in the Vaal River system, South Africa to determine aspects of the morphology, taxonomy and ecology of specimens of this family collected from the gills of Barbus aeneus. Various fish species, namely B. aeneus, Barbus kimberleyensis, Labeo capensis, Labeo umbratus, Cy...

Trophic convergence drives morphological convergence in marine tetrapods.

Science.gov (United States)

Kelley, Neil P; Motani, Ryosuke

2015-01-01

Marine tetrapod clades (e.g. seals, whales) independently adapted to marine life through the Mesozoic and Caenozoic, and provide iconic examples of convergent evolution. Apparent morphological convergence is often explained as the result of adaptation to similar ecological niches. However, quantitative tests of this hypothesis are uncommon. We use dietary data to classify the feeding ecology of extant marine tetrapods and identify patterns in skull and tooth morphology that discriminate trophic groups across clades. Mapping these patterns onto phylogeny reveals coordinated evolutionary shifts in diet and morphology in different marine tetrapod lineages. Similarities in morphology between species with similar diets-even across large phylogenetic distances-are consistent with previous hypotheses that shared functional constraints drive convergent evolution in marine tetrapods.

Economic and hydraulic divergences underpin ecological differentiation in the Bromeliaceae.

Science.gov (United States)

Males, Jamie; Griffiths, Howard

2018-01-01

Leaf economic and hydraulic theories have rarely been applied to the ecological differentiation of speciose herbaceous plant radiations. The role of character trait divergences and network reorganization in the differentiation of the functional types in the megadiverse Neotropical Bromeliaceae was explored by quantifying a range of leaf economic and hydraulic traits in 50 diverse species. Functional types, which are defined by combinations of C 3 or Crassulacean acid metabolism (CAM) photosynthesis, terrestrial or epiphytic habits, and non-specialized, tank-forming or atmospheric morphologies, segregated clearly in trait space. Most classical leaf economic relationships were supported, but they were weakened by the presence of succulence. Functional types differed in trait-network architecture, suggesting that rewiring of trait-networks caused by innovations in habit and photosynthetic pathway is an important aspect of ecological differentiation. The hydraulic data supported the coupling of leaf hydraulics and gas exchange, but not the hydraulic safety versus efficiency hypothesis, and hinted at an important role for the extra-xylary compartment in the control of bromeliad leaf hydraulics. Overall, our findings highlight the fundamental importance of structure-function relationships in the generation and maintenance of ecological diversity. © 2017 The Authors Plant, Cell & Environment Published by John Wiley & Sons Ltd.

Niche divergence facilitated by fine-scale ecological partitioning in a recent cichlid fish adaptive radiation.

Science.gov (United States)

Ford, Antonia G P; Rüber, Lukas; Newton, Jason; Dasmahapatra, Kanchon K; Balarin, John D; Bruun, Kristoffer; Day, Julia J

2016-12-01

Ecomorphological differentiation is a key feature of adaptive radiations, with a general trend for specialization and niche expansion following divergence. Ecological opportunity afforded by invasion of a new habitat is thought to act as an ecological release, facilitating divergence, and speciation. Here, we investigate trophic adaptive morphology and ecology of an endemic clade of oreochromine cichlid fishes (Alcolapia) that radiated along a herbivorous trophic axis following colonization of an isolated lacustrine environment, and demonstrate phenotype-environment correlation. Ecological and morphological divergence of the Alcolapia species flock are examined in a phylogenomic context, to infer ecological niche occupation within the radiation. Species divergence is observed in both ecology and morphology, supporting the importance of ecological speciation within the radiation. Comparison with an outgroup taxon reveals large-scale ecomorphological divergence but shallow genomic differentiation within the Alcolapia adaptive radiation. Ancestral morphological reconstruction suggests lake colonization by a generalist oreochromine phenotype that diverged in Lake Natron to varied herbivorous morphologies akin to specialist herbivores in Lakes Tanganyika and Malawi. © 2016 The Author(s). Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.

Pitfalls in quantifying species turnover: the residency effect

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Kevin Chase Burns

2014-03-01

Full Text Available The composition of ecological communities changes continuously through time and space. Understanding this turnover in species composition is a central goal in biogeography, but quantifying species turnover can be problematic. Here, I describe an underappreciated source of bias in quantifying species turnover, namely ‘the residency effect’, which occurs when the contiguous distributions of species across sampling domains are small relative to census intervals. I present the results of a simulation model that illustrates the problem theoretically and then I demonstrate the problem empirically using a long-term dataset of plant species turnover on islands. Results from both exercises indicate that empirical estimates of species turnover may be susceptible to significant observer bias, which may potentially cloud a better understanding of how the composition of ecological communities changes through time.

Using ecological production functions to link ecological ...

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Ecological production functions (EPFs) link ecosystems, stressors, and management actions to ecosystem services (ES) production. Although EPFs are acknowledged as being essential to improve environmental management, their use in ecological risk assessment has received relatively little attention. Ecological production functions may be defined as usable expressions (i.e., models) of the processes by which ecosystems produce ES, often including external influences on those processes. We identify key attributes of EPFs and discuss both actual and idealized examples of their use to inform decision making. Whenever possible, EPFs should estimate final, rather than intermediate, ES. Although various types of EPFs have been developed, we suggest that EPFs are more useful for decision making if they quantify ES outcomes, respond to ecosystem condition, respond to stressor levels or management scenarios, reflect ecological complexity, rely on data with broad coverage, have performed well previously, are practical to use, and are open and transparent. In an example using pesticides, we illustrate how EPFs with these attributes could enable the inclusion of ES in ecological risk assessment. The biggest challenges to ES inclusion are limited data sets that are easily adapted for use in modeling EPFs and generally poor understanding of linkages among ecological components and the processes that ultimately deliver the ES. We conclude by advocating for the incorporation into E

Ecology of Meimuna mongolica (Hemiptera: Cicadidae) Nymphs: Instars, Morphological Variation, Vertical Distribution and Population Density, Host-Plant Selection, and Emergence Phenology

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Li, Qinglong; Yang, Mingsheng; Liu, Yunxiang; Wei, Cong

2015-01-01

The cicada Meimuna mongolica (Distant) (Hemiptera: Cicadidae) is one of the most important pests of economic forest in Guanzhong Plain of Shaanxi Province, China. Information about ecological characteristics and some sustainable control measures of this species is urgently required for its control. In this study, nymphal instars, morphological variation, vertical distribution, and population density in soil, and emergence phenology of nymphs of M. mongolica on three main host plants (Pinus tabuliformis Carr., Populus tomentosa Carr., and Pyrus xerophila Yü) were studied, based on combined morphological and molecular identification, investigation of the first-instar nymphs hatched from eggs and others excavated from soil, and investigation of exuviae in the adult emergence period. Five nymphal instars of M. mongolica were redetermined according to the distribution plots of the head capsule widths of the nymphs. Nymphs of third and fourth instars showed morphological variation, which is closely related to host-plant association. The mean densities of nymphs in soil under the three host plants were significantly different, indicating a distinct host preference. The nymphs could extend their distribution from the 0–10 cm soil layer to the 51–60 cm soil layer underground but not beyond 60 cm soil layer under all the three host plants. The 21–30 cm soil layer under all the three host plants has the highest nymphal population density. The sex ratio of the entire population was nearly 50:50, but males dominated in the early half of the duration of the emergence. These ecological characteristics of M. mongolica could provide important information for sustainable control measures.

The role of habitat shift in the evolution of lizard morphology: evidence from tropical Tropidurus

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Vitt, Laurie J.; Caldwell, Janalee P.; Zani, Peter A.; Titus, Tom A.

1997-01-01

We compared morphology of two geographically close populations of the tropical lizard Tropidurus hispidus to test the hypothesis that habitat structure influences the evolution of morphology and ecology at the population level. T. hispidus isolated on a rock outcrop surrounded by tropical forest use rock crevices for refuge and appear dorsoventrally compressed compared with those in open savanna. A principal components analysis revealed that the populations were differentially distributed along an axis representing primarily three components of shape: body width, body height, and hind-leg length. Morphological divergence was supported by a principal components analysis of size-free morphological variables. Mitochondrial DNA sequences of ATPase 6 indicate that these populations are closely related relative to other T. hispidus, the rock outcrop morphology and ecology are derived within T. hispidus, and morphological and ecological divergence has occurred more rapidly than genetic divergence. This suggests that natural selection can rapidly adjust morphology and ecology in response to a recent history of exposure to habitats differing in structure, a result heretofore implied from comparative studies among lizard species. PMID:9108063

The role of habitat shift in the evolution of lizard morphology: evidence from tropical Tropidurus.

Science.gov (United States)

Vitt, L J; Caldwell, J P; Zani, P A; Titus, T A

1997-04-15

We compared morphology of two geographically close populations of the tropical lizard Tropidurus hispidus to test the hypothesis that habitat structure influences the evolution of morphology and ecology at the population level. T. hispidus isolated on a rock outcrop surrounded by tropical forest use rock crevices for refuge and appear dorsoventrally compressed compared with those in open savanna. A principal components analysis revealed that the populations were differentially distributed along an axis representing primarily three components of shape: body width, body height, and hind-leg length. Morphological divergence was supported by a principal components analysis of size-free morphological variables. Mitochondrial DNA sequences of ATPase 6 indicate that these populations are closely related relative to other T. hispidus, the rock outcrop morphology and ecology are derived within T. hispidus, and morphological and ecological divergence has occurred more rapidly than genetic divergence. This suggests that natural selection can rapidly adjust morphology and ecology in response to a recent history of exposure to habitats differing in structure, a result heretofore implied from comparative studies among lizard species.

Life on the rocks: habitat use drives morphological and performance evolution in lizards.

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Goodman, Brett A; Miles, Donald B; Schwarzkopf, Lin

2008-12-01

As a group, lizards occupy a vast array of habitats worldwide, yet there remain relatively few cases where habitat use (ecology), morphology, and thus, performance, are clearly related. The best known examples include: increased limb length in response to increased arboreal perch diameter in anoles and increased limb length in response to increased habitat openness for some skinks. Rocky habitats impose strong natural selection on specific morphological characteristics, which differs from that imposed on terrestrial species, because moving about on inclined substrates of irregular sizes and shapes constrains locomotor performance in predictable ways. We quantified habitat use, morphology, and performance of 19 species of lizards (family Scincidae, subfamily Lygosominae) from 23 populations in tropical Australia. These species use habitats with considerable variation in rock availability. Comparative phylogenetic analyses revealed that occupation of rock-dominated habitats correlated with the evolution of increased limb length, compared to species from forest habitats that predominantly occupied leaf litter. Moreover, increased limb length directly affected performance, with species from rocky habitats having greater sprinting, climbing, and clinging ability than their relatives from less rocky habitats. Thus, we found that the degree of rock use is correlated with both morphological and performance evolution in this group of tropical lizards.

Genetics, morphology and ecology reveal a cryptic pika lineage in the Sikkim Himalaya.

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Dahal, Nishma; Lissovsky, Andrey A; Lin, Zhenzhen; Solari, Katherine; Hadly, Elizabeth A; Zhan, Xiangjiang; Ramakrishnan, Uma

2017-01-01

Asian pika species are morphologically ∼similar and have overlapping ranges. This leads to uncertainty and species misidentification in the field. Phylogenetic analyses of such misidentified samples leads to taxonomic ambiguity. The ecology of many pika species remains understudied, particularly in the Himalaya, where sympatric species could be separated by elevation and/or substrate. We sampled, measured, and acquired genetic data from pikas in the Sikkim Himalaya. Our analyses revealed a cryptic lineage, Ochotona sikimaria, previously reported as a subspecies of O. thibetana. The results support the elevation of this lineage to the species level, as it is genetically divergent from O. thibetana, as well as sister species, O. cansus (endemic to central China) and O. curzoniae (endemic to the Tibetan plateau). The Sikkim lineage diverged from its sister species' about 1.7-0.8myrago, coincident with uplift events in the Himalaya. Our results add to the recent spate of cryptic diversity identified from the eastern Himalaya and highlight the need for further study within the Ochotonidae. Copyright © 2016 Elsevier Inc. All rights reserved.

The Bird Community Resilience Index: a novel remote sensing-based biodiversity variable for quantifying ecological integrity

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Michel, N. L.; Wilsey, C.; Burkhalter, C.; Trusty, B.; Langham, G.

2017-12-01

Scalable indicators of biodiversity change are critical to reporting overall progress towards national and global targets for biodiversity conservation (e.g. Aichi Targets) and sustainable development (SDGs). These essential biodiversity variables capitalize on new remote sensing technologies and growth of community science participation. Here we present a novel biodiversity metric quantifying resilience of bird communities and, by extension, of their associated ecological communities. This metric adds breadth to the community composition class of essential biodiversity variables that track trends in condition and vulnerability of ecological communities. We developed this index for use with North American grassland birds, a guild that has experienced stronger population declines than any other avian guild, in order to evaluate gains from the implementation of best management practices on private lands. The Bird Community Resilience Index was designed to incorporate the full suite of species-specific responses to management actions, and be flexible enough to work across broad climatic, land cover, and bird community gradients (i.e., grasslands from northern Mexico through Canada). The Bird Community Resilience Index consists of four components: density estimates of grassland and arid land birds; weighting based on conservation need; a functional diversity metric to incorporate resiliency of bird communities and their ecosystems; and a standardized scoring system to control for interannual variation caused by extrinsic factors (e.g., climate). We present an analysis of bird community resilience across ranches in the Northern Great Plains region of the United States. As predicted, Bird Community Resilience was higher in lands implementing best management practices than elsewhere. While developed for grassland birds, this metric holds great potential for use as an Essential Biodiversity Variable for community composition in a variety of habitat.

Quantifying anthropogenically driven morphologic changes on a barrier island: Fire Island National Seashore, New York

Science.gov (United States)

Kratzmann, Meredith G.; Hapke, Cheryl J.

2012-01-01

Beach scraping, beach replenishment, and the presence of moderate development have altered the morphology of the dune–beach system at Fire Island National Seashore, located on a barrier island on the south coast of Long Island, New York. Seventeen communities are interspersed with sections of natural, nonmodified land within the park boundary. Beach width, dune elevation change, volume change, and shoreline change were calculated from light detection and ranging (LIDAR), real-time kinematic global positioning system (RTK GPS), and beach profile data sets at two ∼4 km long study sites. Each site contains both modified (developed, replenished, and/or scraped) and nonmodified (natural) areas. The analysis spans 9 years, from 1998 to 2007, which encompasses both scraping and replenishment events at Fire Island. The objectives of this study were to quantify and compare morphological changes in modified and nonmodified zones, and to identify erosional areas within the study sites.Areas of increased volume and shoreline accretion were observed at both sites and at the western site are consistent with sand replenishment activities. The results indicate that from 1998 to 2007 locations backed by development and that employed beach scraping and/or replenishment as erosion control measures experienced more loss of volume, width, and dune elevation as compared with adjacent nonmodified areas. A detailed analysis of one specific modification, beach scraping, shows distinct morphological differences in scraped areas relative to nonscraped areas of the beach. In general, scraped areas where there is development on the dunes showed decreases in all measured parameters and are more likely to experience overwash during storm events. Furthermore, the rapid mobilization of material from the anthropogenic (scraped) dune results in increased beach accretion downcoast.National park lands are immediately adjacent to developed areas on Fire Island, and even relatively small human

Scale Morphology and Micro-Structure of Monitor Lizards (Squamata: Varanidae: Varanus spp.) and their Allies: Implications for Systematics, Ecology, and Conservation.

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Bucklitsch, Yannick; Böhme, Wolfgang; Koch, André

2016-08-17

We analysed scale morphology and micro-structure from five different body regions using scanning electron microscopy (SEM) across all nine recognized subgenera of the monitor lizard genus Varanus including 41 different species investigated. As far as we are aware, this qualitative visual technique was applied by us for the first time to most monitor lizard species and probably also to the primary outgroup and sister species Lanthanotus borneensis. A comprehensive list of 20 scalation characters each with up to seven corresponding character states was established and defined for the five body regions sampled. For the phylogenetic approach, parsimony analyses of the resulting morphological data matrix as well as Bremer and bootstrap support calculations were performed with the software TNT. Our results demonstrate that a variety of micro-ornamentations (i.e., ultra- or micro-dermatoglyphics) as seen in various squamate groups is hardly present in monitor lizards. In several species from six out of nine subgenera, however, we found a honeycomb-shaped micro-structure of foveate polygons. Two further samples of Euprepiosaurus Fitzinger, 1843 exhibit each another unique microscopic structure on the scale surface. Notably, the majority of species showing the honeycombed ultra-structure inhabit arid habitats in Australia, Africa and the Middle East. Therefore, it can be inferred that this microscopic scalation feature, which has also been identified in other desert dwelling lizard species, is taxonomically and ecologically correlated with a xeric habitat type in varanids, too. In addition, the systematic affiliation of V. spinulosus, an endemic monitor lizard species from the Solomon Islands with an extraordinary scale shape, is discussed in the light of current hypotheses about its phylogenetic position within the Varanidae. Due to its unique scalation characteristics, in combination with other morphological evidence, a new monotypic subgenus, Solomonsaurus subgen. nov

Morphological Variation and Ecological Structure of Iroko (Milicia excelsa Welw. C.C. Berg) Populations across Different Bio geographical Zones in Benin

International Nuclear Information System (INIS)

Ouinsavi, C.; Sokpon, N.

2010-01-01

Iroko (Milicia excelsa) is a commercially important timber tree species formerly known by local people in Benin. Because of the highly attractive technological properties of its wood and its multipurpose uses, the species was subjected to intensive human pressure. Apart from strong climate oscillation during the Pleistocene, human caused habitat fragmentation through continuous land clearing for agriculture, extensive forests exploitation and urbanization induced the occurrence of many isolated forest plots and trees species among which Milicia excelsa trees. As fragmentation was proved to have deleterious effects on genetic diversity within a species and its morphological structure, it was of interest to investigate the current demographic, morphological and genetic structure of M. excelsa before coming up with conservation strategies. In the current study, morphological variation and ecological structure of M. excelsa populations were assessed in Benin using transect sampling method and multivariate analyses including principal component, cluster and canonical discriminant analyses. On the basis of morphological parameters, M. excelsa individuals and populations were clustered into four and discrimination of groups indicated that most of variations were highly related to edaphic factors and annual rainfall. Erratic diameter distribution was found for many populations although most of them showed bell shaped diameter distribution.

Ecological associations of autopodial osteology in Neotropical geckos.

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Rothier, Priscila S; Brandt, Renata; Kohlsdorf, Tiana

2017-03-01

Coevolution of form and function inspires investigation of associations between morphological variation and the exploitation of specific ecological settings. Such relationships, based mostly on traits of external morphology, have been extensively described for vertebrates, and especially so for squamates. External features are, however, composed by both soft tissues and bones, and these likely play different biomechanical roles during locomotion, such as in the autopodia. Therefore, ecological trends identified on the basis of external morphological measurements may not be directly correlated with equivalent variation in osteology. Here, we investigate how refined parameters of autopodial osteology relate to ecology, by contrasting climbing and nonclimbing geckos. Our first step consisted of inferring how external and osteological morphometric traits coevolved in the group. Our results corroborate the hypothesis of coevolution between external and osteological elements in the autopodia of geckos, and provides evidence for associations between specific osteological traits and preferred locomotor habit. Specifically, nonclimbers exhibit longer ultimate and penultimate phalanges of Digit V in the manus and pes and also a longer fifth metatarsal in comparison with climbers, a pattern discussed here in the context of the differential demands made upon locomotion in specific ecological contexts. Our study highlights the relevance of osteological information for discussing the evolution of ecological associations of the tetrapod autopodium. J. Morphol. 278:290-299, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Continental cichlid radiations: functional diversity reveals the role of changing ecological opportunity in the Neotropics.

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Arbour, Jessica Hilary; López-Fernández, Hernán

2016-08-17

Adaptive radiations have been hypothesized to contribute broadly to the diversity of organisms. Models of adaptive radiation predict that ecological opportunity and ecological release, the availability of empty ecological niches and the response by adapting lineages to occupy them, respectively, drive patterns of phenotypic and lineage diversification. Adaptive radiations driven by 'ecological opportunity' are well established in island systems; it is less clear if ecological opportunity influences continent-wide diversification. We use Neotropical cichlid fishes to test if variation in rates of functional evolution is consistent with changing ecological opportunity. Across a functional morphological axis associated with ram-suction feeding traits, evolutionary rates declined through time as lineages diversified in South America. Evolutionary rates of ram-suction functional morphology also appear to have accelerated as cichlids colonized Central America and encountered renewed opportunity. Our results suggest that ecological opportunity may play an important role in shaping patterns of morphological diversity of even broadly distributed lineages like Neotropical cichlids. © 2016 The Author(s).

Tracing early stages of species differentiation: Ecological, morphological and genetic divergence of Galápagos sea lion populations

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Brunner Sylvia

2008-05-01

Full Text Available Abstract Background Oceans are high gene flow environments that are traditionally believed to hamper the build-up of genetic divergence. Despite this, divergence appears to occur occasionally at surprisingly small scales. The Galápagos archipelago provides an ideal opportunity to examine the evolutionary processes of local divergence in an isolated marine environment. Galápagos sea lions (Zalophus wollebaeki are top predators in this unique setting and have an essentially unlimited dispersal capacity across the entire species range. In theory, this should oppose any genetic differentiation. Results We find significant ecological, morphological and genetic divergence between the western colonies and colonies from the central region of the archipelago that are exposed to different ecological conditions. Stable isotope analyses indicate that western animals use different food sources than those from the central area. This is likely due to niche partitioning with the second Galápagos eared seal species, the Galápagos fur seal (Arctocephalus galapagoensis that exclusively dwells in the west. Stable isotope patterns correlate with significant differences in foraging-related skull morphology. Analyses of mitochondrial sequences as well as microsatellites reveal signs of initial genetic differentiation. Conclusion Our results suggest a key role of intra- as well as inter-specific niche segregation in the evolution of genetic structure among populations of a highly mobile species under conditions of free movement. Given the monophyletic arrival of the sea lions on the archipelago, our study challenges the view that geographical barriers are strictly needed for the build-up of genetic divergence. The study further raises the interesting prospect that in social, colonially breeding mammals additional forces, such as social structure or feeding traditions, might bear on the genetic partitioning of populations.

Ecological release in lizard assemblages of neotropical savannas.

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Mesquita, Daniel Oliveira; Colli, Guarino Rinaldi; Vitt, Laurie J

2007-08-01

We compare lizard assemblages of Cerrado and Amazonian savannas to test the ecological release hypothesis, which predicts that niche dimensions and abundance should be greater in species inhabiting isolated habitat patches with low species richness (Amazonian savannas and isolated Cerrado patches) when compared with nonisolated areas in central Cerrado with greater species richness. We calculated microhabitat and diet niche breadths with data from 14 isolated Cerrado patches and Amazon savanna areas and six central Cerrado populations. Morphological data were compared using average Euclidean distances, and lizard abundance was estimated using the number of lizards captured in pitfall traps over an extended time period. We found no evidence of ecological release with respect to microhabitat use, suggesting that historical factors are better microhabitat predictors than ecological factors. However, data from individual stomachs indicate that ecological release occurs in these areas for one species (Tropidurus) but not others (Ameiva ameiva, Anolis, Cnemidophorus, and Micrablepharus), suggesting that evolutionary lineages respond differently to environmental pressures, with tropidurids being more affected by ecological factors than polychrotids, teiids, and gymnophthalmids. We found no evidence that ecological release occurs in these areas using morphological data. Based on abundance data, our results indicate that the ecological release (density compensation) hypothesis is not supported: lizard species are not more abundant in isolated areas than in nonisolated areas. The ecology of species is highly conservative, varying little from assemblage to assemblage. Nevertheless, increases in niche breadth for some species indicate that ecological release occurs as well.

Inferring local ecological processes amid species pool influences

DEFF Research Database (Denmark)

Lessard, Jean-Philippe; Belmaker, Jonathan; Myers, Jonathan A.

2012-01-01

studies, null models of community structure, and ecologically explicit definitions of the species pool as a means to compare predominant ecological processes among regions. By uniting concepts and tools from community ecology and macroecology, this approach might facilitate synthesis and resolve many......Resolving contingencies in community ecology requires comparative studies of local communities along broad-scale environmental gradients and in different biogeographic regions. However, comparisons of local ecological processes among regions require a synthetic understanding of how the species pool...... of potential community members influences the structure of ecological communities. Here, we outline an integrative approach for quantifying local ecological processes while explicitly accounting for species pool influences. Specifically, we highlight the utility of combining geographically replicated local...

Mobilifilum chasei: morphology and ecology of a spirochete from an intertidal stratified microbial mat community

Science.gov (United States)

Margulis, L.; Hinkle, G.; Stolz, J.; Craft, F.; Esteve, I.; Guerrero, R.

1990-01-01

Spirochetes were found in the lower anoxiphototrophic layer of a stratified microbial mat (North Pond, Laguna Figueroa, Baja California, Mexico). Ultra-structural analysis of thin sections of field samples revealed spirochetes approximately 0.25 micrometer in diameter with 10 or more periplasmic flagella, leading to the interpretation that these spirochetes bear 10 flagellar insertions on each end. Morphometric study showed these free-living spirochetes greatly resemble certain symbiotic ones, i.e., Borrelia and certain termite spirochetes, the transverse sections of which are presented here. The ultrastructure of this spirochete also resembles Hollandina and Diplocalyx (spirochetes symbiotic in arthropods) more than it does Spirochaeta, the well known genus of mud-dwelling spirochetes. The new spirochete was detected in mat material collected both in 1985 and in 1987. Unique morphology (i.e., conspicuous outer coat of inner membrane, large number of periplasmic flagella) and ecology prompt us to name a new free-living spirochete.

CONTRIBUTIONS TO THE FUNCTIONAL MORPHOLOGY OF ...

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CONTRIBUTIONS TO THE FUNCTIONAL MORPHOLOGY OF FISHES ... The exact phylogeny of the chimaeroids is obscure due to difficulties encountered in ...... species was obtained from the University of Cape Town Ecological Records;.

Quantifying accelerated soil erosion through ecological site-based assessments of wind and water erosion

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This work explores how organising soil erosion assessments using established groupings of similar soils (ecological sites) can inform systems for managing accelerated soil erosion. We evaluated aeolian sediment transport and fluvial erosion rates for five ecological sites in southern New Mexico, USA...

Distribution, morphological variability, ecology and the present state of Nitella from Lake Ohrid and its surroundings

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Trajanovska Sonja

2012-01-01

Full Text Available Our research into 52 profiles of the littoral zone of the Macedonian part of Lake Ohrid and numerous samples taken from its surroundings has resulted in a detailed picture of the composition of the Charophyta vegetation in the lake. The results of the research also include data regarding the species composition and present state of Nitella. The dominant species of Nitella is Nitella opaca, which is characterized by a specific distribution, morphological variability and ecology. The present state of Nitella is not steady, especially in the watershed of the lake, since in this area there are some permanent changes in the hydrology of the terrain. Therefore, there is a need to establish long-term and complex monitoring which will result in the prompt detection of risk factors and influences, thereby enabling a rapid reaction to a possible newly emerged negative state.

THE DISTRIBUTION, MORPHOLOGY, AND ECOLOGY OF THREE INTRODUCED ASIATIC SPECIES OF PORPHYRA (BANGIALES, RHODOPHYTA) IN THE NORTHWESTERN ATLANTIC(1).

Science.gov (United States)

Neefus, Christopher D; Mathieson, Arthur C; Bray, Troy L; Yarish, Charles

2008-12-01

Distributions of three Asiatic Porphyra species, Porphyra yezoensis Ueda, Porphyra katadae A. Miura, and Porphyra suborbiculata Kjellm., are reported from New England, USA. Species identifications were confirmed by rbcL and nuclear ribosomal DNA internal transcribed spacer-1 (ITS1) sequence comparisons with herbarium specimens, cultures, and GenBank accessions. Two distinct genotypes of P. yezoensis were detected: forma narawaensis A. Miura and f. yezoensis. Forma narawaensis occurs south of Cape Cod, Massachusetts, and has ITS1 sequences identical to cultivars widely grown in Japan. Forma yezoensis occurs in western Long Island Sound and from Cape Cod northward to midcoastal Maine; its ITS1 sequence is identical to a wild specimen from Hokkaido, Japan. P. katadae has been collected from five locations near Cape Cod; its ITS1 sequence is identical to a cultured specimen from Qingdao, China. P. suborbiculata has been collected at several locations south of Cape Cod; its presence in North Carolina and Delaware during the mid-1960s was confirmed from herbarium specimens. Morphological and ecological characteristics for New England populations of the three Asiatic species were compared to original descriptions. New England P. yezoensis f. yezoensis is similar to Ueda's original description of Japanese specimens, but there are morphological differences for P. yezoensis f. narawaensis. In New England, f. narawaensis typically does not attain the length reported in Japan (max. 19 cm versus 100 cm). New England P. katadae is similar to Miura's original description, except for slight differences in thallus thickness and reproductive patterns. By contrast, New England, Japanese, and other populations of P. suborbiculata exhibit pronounced differences in blade coloration, shape and dimensions, reproductive patterns, seasonal occurrence, and general ecology. © 2008 Phycological Society of America.

Investigating ecological speciation in non-model organisms

DEFF Research Database (Denmark)

Foote, Andrew David

2012-01-01

Background: Studies of ecological speciation tend to focus on a few model biological systems. In contrast, few studies on non-model organisms have been able to infer ecological speciation as the underlying mechanism of evolutionary divergence. Questions: What are the pitfalls in studying ecological...... speciation in non-model organisms that lead to this bias? What alternative approaches might redress the balance? Organism: Genetically differentiated types of the killer whale (Orcinus orca) exhibiting differences in prey preference, habitat use, morphology, and behaviour. Methods: Review of the literature...... on killer whale evolutionary ecology in search of any difficulty in demonstrating causal links between variation in phenotype, ecology, and reproductive isolation in this non-model organism. Results: At present, we do not have enough evidence to conclude that adaptive phenotype traits linked to ecological...

Quantifying levels of animal activity using camera trap data

NARCIS (Netherlands)

Rowcliffe, J.M.; Kays, R.; Kranstauber, B.; Carbone, C.; Jansen, P.A.

2014-01-01

1.Activity level (the proportion of time that animals spend active) is a behavioural and ecological metric that can provide an indicator of energetics, foraging effort and exposure to risk. However, activity level is poorly known for free-living animals because it is difficult to quantify activity

Rates of ecological divergence and body size evolution are correlated with species diversification in scaly tree ferns

Science.gov (United States)

Ramírez-Barahona, Santiago; Barrera-Redondo, Josué; Eguiarte, Luis E.

2016-01-01

Variation in species richness across regions and between different groups of organisms is a major feature of evolution. Several factors have been proposed to explain these differences, including heterogeneity in the rates of species diversification and the age of clades. It has been frequently assumed that rapid rates of diversification are coupled to high rates of ecological and morphological evolution, leading to a prediction that remains poorly explored for most species: the positive association between ecological niche divergence, morphological evolution and species diversification. We combined a time-calibrated phylogeny with distribution, ecological and body size data for scaly tree ferns (Cyatheaceae) to test whether rates of species diversification are predicted by the rates at which clades have evolved distinct ecological niches and body sizes. We found that rates of species diversification are positively correlated with rates of ecological and morphological evolution, with rapidly diversifying clades also showing rapidly evolving ecological niches and body sizes. Our results show that rapid diversification of scaly tree ferns is associated with the evolution of species with comparable morphologies that diversified into similar, yet distinct, environments. This suggests parallel evolutionary pathways opening in different tropical regions whenever ecological and geographical opportunities arise. Accordingly, rates of ecological niche and body size evolution are relevant to explain the current patterns of species richness in this ‘ancient’ fern lineage across the tropics. PMID:27412279

Rates of ecological divergence and body size evolution are correlated with species diversification in scaly tree ferns.

Science.gov (United States)

Ramírez-Barahona, Santiago; Barrera-Redondo, Josué; Eguiarte, Luis E

2016-07-13

Variation in species richness across regions and between different groups of organisms is a major feature of evolution. Several factors have been proposed to explain these differences, including heterogeneity in the rates of species diversification and the age of clades. It has been frequently assumed that rapid rates of diversification are coupled to high rates of ecological and morphological evolution, leading to a prediction that remains poorly explored for most species: the positive association between ecological niche divergence, morphological evolution and species diversification. We combined a time-calibrated phylogeny with distribution, ecological and body size data for scaly tree ferns (Cyatheaceae) to test whether rates of species diversification are predicted by the rates at which clades have evolved distinct ecological niches and body sizes. We found that rates of species diversification are positively correlated with rates of ecological and morphological evolution, with rapidly diversifying clades also showing rapidly evolving ecological niches and body sizes. Our results show that rapid diversification of scaly tree ferns is associated with the evolution of species with comparable morphologies that diversified into similar, yet distinct, environments. This suggests parallel evolutionary pathways opening in different tropical regions whenever ecological and geographical opportunities arise. Accordingly, rates of ecological niche and body size evolution are relevant to explain the current patterns of species richness in this 'ancient' fern lineage across the tropics. © 2016 The Author(s).

Quantifying the Adaptive Cycle.

Directory of Open Access Journals (Sweden)

David G Angeler

Full Text Available The adaptive cycle was proposed as a conceptual model to portray patterns of change in complex systems. Despite the model having potential for elucidating change across systems, it has been used mainly as a metaphor, describing system dynamics qualitatively. We use a quantitative approach for testing premises (reorganisation, conservatism, adaptation in the adaptive cycle, using Baltic Sea phytoplankton communities as an example of such complex system dynamics. Phytoplankton organizes in recurring spring and summer blooms, a well-established paradigm in planktology and succession theory, with characteristic temporal trajectories during blooms that may be consistent with adaptive cycle phases. We used long-term (1994-2011 data and multivariate analysis of community structure to assess key components of the adaptive cycle. Specifically, we tested predictions about: reorganisation: spring and summer blooms comprise distinct community states; conservatism: community trajectories during individual adaptive cycles are conservative; and adaptation: phytoplankton species during blooms change in the long term. All predictions were supported by our analyses. Results suggest that traditional ecological paradigms such as phytoplankton successional models have potential for moving the adaptive cycle from a metaphor to a framework that can improve our understanding how complex systems organize and reorganize following collapse. Quantifying reorganization, conservatism and adaptation provides opportunities to cope with the intricacies and uncertainties associated with fast ecological change, driven by shifting system controls. Ultimately, combining traditional ecological paradigms with heuristics of complex system dynamics using quantitative approaches may help refine ecological theory and improve our understanding of the resilience of ecosystems.

Squamation and ecology of thelodonts.

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Humberto G Ferrón

Full Text Available Thelodonts are an enigmatic group of Paleozoic jawless vertebrates that have been well studied from taxonomical, biostratigraphic and paleogeographic points of view, although our knowledge of their ecology and mode of life is still scant. Their bodies were covered by micrometric scales whose morphology, histology and the developmental process are extremely similar to those of extant sharks. Based on these similarities and on the well-recognized relationship between squamation and ecology in sharks, here we explore the ecological diversity and lifestyles of thelodonts. For this we use classic morphometrics and discriminant analysis to characterize the squamation patterns of a significant number of extant shark species whose ecology is well known. Multivariate analyses have defined a characteristic squamation pattern for each ecological group, thus establishing a comparative framework for inferring lifestyles in thelodonts. We then use this information to study the squamation of the currently described 147 species of thelodonts, known from both articulated and disarticulated remains. Discriminant analysis has allowed recognizing squamation patterns comparable to those of sharks and links them to specific ecological groups. Our results suggest a remarkable ecological diversity in thelodonts. A large number of them were probably demersal species inhabiting hard substrates, within caves and crevices in rocky environments or reefs, taking advantage of the flexibility provided by their micromeric squamations. Contrary to classical interpretations, only few thelodonts were placed among demersal species inhabiting sandy and muddy substrates. Schooling species with defensive scales against ectoparasites could be also abundant suggesting that social interactions and pressure of ectoparasites were present in vertebrates as early the Silurian. The presence of species showing scales suggestive of low to moderate speed and a lifestyle presumably associated

Phenotypic disparity in Iberian short-horned grasshoppers (Acrididae): the role of ecology and phylogeny.

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García-Navas, Vicente; Noguerales, Víctor; Cordero, Pedro J; Ortego, Joaquín

2017-05-04

The combination of model-based comparative techniques, disparity analyses and ecomorphological correlations constitutes a powerful method to gain insight into the evolutionary mechanisms that shape morphological variation and speciation processes. In this study, we used a time-calibrated phylogeny of 70 Iberian species of short-horned grasshoppers (Acrididae) to test for patterns of morphological disparity in relation to their ecology and phylogenetic history. Specifically, we examined the role of substrate type and level of ecological specialization in driving different aspects of morphological evolution (locomotory traits, chemosensitive organs and cranial morphology) in this recent radiation. We found a bimodal distribution of locomotory attributes corresponding to the two main substrate type guilds (plant vs. ground); plant-perching species tend to exhibit larger wings and thicker femora than those that remain on the ground. This suggests that life form (i.e., substrate type) is an important driving force in the evolution of morphological traits in short-horned grasshoppers, irrespective of ancestry. Substrate type and ecological specialization had no significant influence on head shape, a trait that showed a strong phylogenetic conservatism. Finally, we also found a marginal significant association between the length of antennae and the level of ecological specialization, suggesting that the development of sensory organs may be favored in specialist species. Our results provide evidence that even in taxonomic groups showing limited morphological and ecological disparity, natural selection seems to play a more important role than genetic drift in driving the speciation process. Overall, this study suggests that morphostatic radiations should not necessarily be considered as "non-adaptive" and that the speciation process can bind both adaptive divergence mechanisms and neutral speciation processes related with allopatric and/or reproductive isolation.

Data Assimilation at FLUXNET to Improve Models towards Ecological Forecasting (Invited)

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Luo, Y.

2009-12-01

Dramatically increased volumes of data from observational and experimental networks such as FLUXNET call for transformation of ecological research to increase its emphasis on quantitative forecasting. Ecological forecasting will also meet the societal need to develop better strategies for natural resource management in a world of ongoing global change. Traditionally, ecological forecasting has been based on process-based models, informed by data in largely ad hoc ways. Although most ecological models incorporate some representation of mechanistic processes, today’s ecological models are generally not adequate to quantify real-world dynamics and provide reliable forecasts with accompanying estimates of uncertainty. A key tool to improve ecological forecasting is data assimilation, which uses data to inform initial conditions and to help constrain a model during simulation to yield results that approximate reality as closely as possible. In an era with dramatically increased availability of data from observational and experimental networks, data assimilation is a key technique that helps convert the raw data into ecologically meaningful products so as to accelerate our understanding of ecological processes, test ecological theory, forecast changes in ecological services, and better serve the society. This talk will use examples to illustrate how data from FLUXNET have been assimilated with process-based models to improve estimates of model parameters and state variables; to quantify uncertainties in ecological forecasting arising from observations, models and their interactions; and to evaluate information contributions of data and model toward short- and long-term forecasting of ecosystem responses to global change.

Morphological divergence in a continental adaptive radiation: South American ovenbirds of the genus Cinclodes

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Rader, Jonathan A.; Dillon, Michael E.; Chesser, R. Terry; Sabat, Pablo; Martinez del Rio, Carlos

2015-01-01

Cinclodes is an ecologically diverse genus of South American passerine birds and represents a case of continental adaptive radiation along multiple axes. We investigated morphological diversification in Cinclodes using a comprehensive set of morphometric measurements of study skins. Principal component analysis identified 2 primary axes of morphological variation: one describing body size and a second capturing differences in wing-tip shape and toe length. Phylogenetic analyses of the first principal component suggest an early divergence ofCinclodes into 2 main clades characterized by large and small body sizes. We suggest that 2 morphological outliers within these main clades (C. antarcticus and C. palliatus) may be cases of island gigantism and that a third (C. patagonicus) may reflect ecological character displacement. Despite its ecological and physiological diversity, the genus Cinclodes does not appear to show morphological diversity beyond what is typical of other avian genera.

Trophic divergence despite morphological convergence in a continental radiation of snakes.

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Grundler, Michael C; Rabosky, Daniel L

2014-07-22

Ecological and phenotypic convergence is a potential outcome of adaptive radiation in response to ecological opportunity. However, a number of factors may limit convergence during evolutionary radiations, including interregional differences in biogeographic history and clade-specific constraints on form and function. Here, we demonstrate that a single clade of terrestrial snakes from Australia--the oxyuranine elapids--exhibits widespread morphological convergence with a phylogenetically diverse and distantly related assemblage of snakes from North America. Australian elapids have evolved nearly the full spectrum of phenotypic modalities that occurs among North American snakes. Much of the convergence appears to involve the recurrent evolution of stereotyped morphologies associated with foraging mode, locomotion and habitat use. By contrast, analysis of snake diets indicates striking divergence in feeding ecology between these faunas, partially reflecting regional differences in ecological allometry between Australia and North America. Widespread phenotypic convergence with the North American snake fauna coupled with divergence in feeding ecology are clear examples of how independent continental radiations may converge along some ecological axes yet differ profoundly along others. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

The logic of ecological patchiness.

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Grünbaum, Daniel

2012-04-06

Most ecological interactions occur in environments that are spatially and temporally heterogeneous-'patchy'-across a wide range of scales. In contrast, most theoretical models of ecological interactions, especially large-scale models applied to societal issues such as climate change, resource management and human health, are based on 'mean field' approaches in which the underlying patchiness of interacting consumers and resources is intentionally averaged out. Mean field ecological models typically have the advantages of tractability, few parameters and clear interpretation; more technically complex spatially explicit models, which resolve ecological patchiness at some (or all relevant) scales, generally lack these advantages. This report presents a heuristic analysis that incorporates important elements of consumer-resource patchiness with minimal technical complexity. The analysis uses scaling arguments to establish conditions under which key mechanisms-movement, reproduction and consumption-strongly affect consumer-resource interactions in patchy environments. By very general arguments, the relative magnitudes of these three mechanisms are quantified by three non-dimensional ecological indices: the Frost, Strathmann and Lessard numbers. Qualitative analysis based on these ecological indices provides a basis for conjectures concerning the expected characteristics of organisms, species interactions and ecosystems in patchy environments.

Ecological and phylogenetic influences on maxillary dentition in snakes

Directory of Open Access Journals (Sweden)

Kate Jackson

2010-12-01

Full Text Available The maxillary dentition of snakes was used as a system with which to investigate the relative importance of the interacting forces of ecological selective pressures and phylogenetic constraints indetermining morphology. The maxillary morphology of three groups of snakes having different diets, with each group comprising two distinct lineages — boids and colubroids — was examined. Our results suggest that dietary selective pressures may be more significantthan phylogenetic history in shaping maxillary morphology.

Evolution of asynchronous motor activity in paired muscles: effects of ecology, morphology, and phylogeny.

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Gerry, Shannon P; Ramsay, Jason B; Dean, Mason N; Wilga, Cheryl D

2008-08-01

Many studies of feeding behavior have implanted electrodes unilaterally (in muscles on only one side of the head) to determine the basic motor patterns of muscles controlling the jaws. However, bilateral implantation has the potential to achieve a more comprehensive understanding of modification of the motor activity that may be occurring between the left and right sides of the head. In particular, complex processing of prey is often characterized by bilaterally asynchronous and even unilateral activation of the jaw musculature. In this study, we bilaterally implant feeding muscles in species from four orders of elasmobranchs (Squaliformes, Orectolobiformes, Carcharhiniformes, Rajoidea) in order to characterize the effects of type of prey, feeding behavior, and phylogeny on the degree of asynchronous muscle activation. Electrodes were implanted in three of the jaw adductors, two divisions of the quadratomandibularis and the preorbitalis, as well as in a cranial elevator in sharks, the epaxialis. The asynchrony of feeding events (measured as the degree to which activity of members of a muscle pair is out of phase) was compared across species for capture versus processing and simple versus complex prey, then interpreted in the contexts of phylogeny, morphology, and ecology to clarify determinants of asynchronous activity. Whereas capture and processing of prey were characterized by statistically similar degrees of asynchrony for data pooled across species, events involving complex prey were more asynchronous than were those involving simple prey. The two trophic generalists, Squalus acanthias and Leucoraja erinacea, modulated the degree of asynchrony according to type of prey, whereas the two behavioral specialists, Chiloscyllium plagiosum and Mustelus canis, activated the cranial muscles synchronously regardless of type of prey. These differences in jaw muscle activity would not have been detected with unilateral implantation. Therefore, we advocate bilateral

An approach to unraveling the coexistence of snappers (Lutjanidae using otolith morphology

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Zahra Sadighzadeh

2014-09-01

Full Text Available The sagittae otolith morphology of marine fishes has been used in many ecomorphological studies to explain certain ecological adaptations of species to habitat. Our study compares the sagittal otolith shapes of ten species of snappers (Family Lutjanidae inhabiting the Persian Gulf. We used a morphometric analysis of the otolith measurements (length, height, perimeter, area and weight and of the ratio between the area of the sulcus acusticus and the area of the otolith (S:O. The otolith contour was also analysed using wavelets as a mathematical descriptor. Morphological variations in the otoliths were associated with the morphology and external colouration of snappers as well as ecological traits. An analysis of the interspecific S:O ratio suggested that the highest ratios occurred in snappers inhabiting shallower waters. A categorical multivariate analysis, including morphological, ecological and otolith size factors, showed that the species adapted to dim light conditions had a greater otolith perimeter. An analysis of variance of the otolith contour revealed zones with a higher interspecific variability, although only the antero-dorsal zone showed differing patterns. Although the otolith patterns appear to have a phylogenetic component, they might also be related to diel activity rhythms or to the light conditions in the habitat. The results of the study showed that variation in otolith morphology can be used to explain the coexistence of sympatric species.

Can they dig it? Functional morphology and semifossoriality among small-eared shrews, genus Cryptotis (Mammalia, Soricidae)

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Woodman, Neal; Gaffney, Sarah A.

2014-01-01

Small-eared shrews (Mammalia: Soricidae: Cryptotis), exhibit modifications of the forelimb skeleton that have been interpreted as adaptations for semifossoriality. Most species inhabit remote regions, however, and their locomotory and foraging behaviors remain mostly speculative. To better understand the morphological modifications in the absence of direct observations, we quantified variation in these species by measuring 151 individuals representing 18 species and populations of Cryptotis and two species of moles (Talpidae) for comparison. From our measurements, we calculated 22 indices, most of which have been used previously to characterize substrate use among rodents and other taxa. We analyzed the indices using 1) average percentile ranks, 2) principal components analysis, and 3) cluster analysis. From these analyses, we determined that three basic modes of substrate adaptation are present within Cryptotis: 1) a primarily terrestrial mode, with species that are capable of burrowing, but lack adaptations to increase digging efficiency, 2) a semifossorial mode, with species whose forelimbs bones show strong muscle attachment areas and increased mechanical advantage, and 3) an intermediate mode. In addition to identifying new morphological characters and contributing to our understanding of the functional morphology of soricids, these analyses provide additional insight into the ecology of the species of interest.

Modelling dendritic ecological networks in space: An integrated network perspective

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Erin E. Peterson; Jay M. Ver Hoef; Dan J. Isaak; Jeffrey A. Falke; Marie-Josee Fortin; Chris E. Jordan; Kristina McNyset; Pascal Monestiez; Aaron S. Ruesch; Aritra Sengupta; Nicholas Som; E. Ashley Steel; David M. Theobald; Christian E. Torgersen; Seth J. Wenger

2013-01-01

Dendritic ecological networks (DENs) are a unique form of ecological networks that exhibit a dendritic network topology (e.g. stream and cave networks or plant architecture). DENs have a dual spatial representation; as points within the network and as points in geographical space. Consequently, some analytical methods used to quantify relationships in other types of...

Quantifying and Mapping Habitat-Based Biodiversity Metrics Within an Ecosystem Services Framework

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Ecosystem services have become a key issue of this century in resource management, conservation planning, human well-being, and environmental decision analysis. Mapping and quantifying ecosystem services have become strategic national interests for integrating ecology with econom...

Exergy method technical and ecological applications

CERN Document Server

Szargut, J

2005-01-01

The exergy method makes it possible to detect and quantify the possibilities of improving thermal and chemical processes and systems. The introduction of the concept ""thermo-ecological cost"" (cumulative consumption of non-renewable natural exergy resources) generated large application possibilities of exergy in ecology. This book contains a short presentation on the basic principles of exergy analysis and discusses new achievements in the field over the last 15 years. One of the most important issues considered by the distinguished author is the economy of non-renewable natural exergy.

Beach morphology monitoring in the Elwha River Littoral Cell, 2004-2009

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Warrick, Jonathon A.; George, Douglas A.; Stevens, Andrew W.; Eshleman, Jodi; Gelfenbaum, Guy; Kaminsky, George M.; Schwartz, Andrew K.; Bierne, Matt

2007-01-01

This report describes the methods used, data collected, and results of the Beach Morphology Monitoring Program in the Elwha River Littoral Cell, starting in 2004. The U.S. Geological Survey and the Washington State Department of Ecology collaborated in the data collection with the support of the local Lower Elwha Klallam Tribe. Beach monitoring efforts consisted of collecting topographic and bathymetric horizontal and vertical position data by using a Real Time Kinematic Differential Global Positioning System (RTK-DGPS). The monitoring program was designed to characterize the littoral system of the Elwha River before the scheduled removal of two large dams in 2012. A primary objective of this work is to quantitatively describe the topography and bathymetry of the Elwha River littoral system so that the effects of dam removal may be quantified. Sediment inputs following dam removal are hypothesized to result in (A) larger amounts of fine sediment grain-sizes entering the littoral system and, (B) a reduction or reversal of coastal erosion.

Nanoscale Morphology of Doctor Bladed versus Spin-Coated Organic Photovoltaic Films

KAUST Repository

Pokuri, Balaji Sesha Sarath; Sit, Joseph; Wodo, Olga; Baran, Derya; Ameri, Tayebeh; Brabec, Christoph J.; Moule, Adam J.; Ganapathysubramanian, Baskar

2017-01-01

Recent advances in efficiency of organic photovoltaics are driven by judicious selection of processing conditions that result in a “desired” morphology. An important theme of morphology research is quantifying the effect of processing conditions

Modelling dendritic ecological networks in space: anintegrated network perspective

Science.gov (United States)

Peterson, Erin E.; Ver Hoef, Jay M.; Isaak, Dan J.; Falke, Jeffrey A.; Fortin, Marie-Josée; Jordon, Chris E.; McNyset, Kristina; Monestiez, Pascal; Ruesch, Aaron S.; Sengupta, Aritra; Som, Nicholas; Steel, E. Ashley; Theobald, David M.; Torgersen, Christian E.; Wenger, Seth J.

2013-01-01

Dendritic ecological networks (DENs) are a unique form of ecological networks that exhibit a dendritic network topology (e.g. stream and cave networks or plant architecture). DENs have a dual spatial representation; as points within the network and as points in geographical space. Consequently, some analytical methods used to quantify relationships in other types of ecological networks, or in 2-D space, may be inadequate for studying the influence of structure and connectivity on ecological processes within DENs. We propose a conceptual taxonomy of network analysis methods that account for DEN characteristics to varying degrees and provide a synthesis of the different approaches within

The Allometry of Bee Proboscis Length and Its Uses in Ecology.

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Daniel P Cariveau

Full Text Available Allometric relationships among morphological traits underlie important patterns in ecology. These relationships are often phylogenetically shared; thus quantifying allometric relationships may allow for estimating difficult-to-measure traits across species. One such trait, proboscis length in bees, is assumed to be important in structuring bee communities and plant-pollinator networks. However, it is difficult to measure and thus rarely included in ecological analyses. We measured intertegular distance (as a measure of body size and proboscis length (glossa and prementum, both individually and combined of 786 individual bees of 100 species across 5 of the 7 extant bee families (Hymenoptera: Apoidea: Anthophila. Using linear models and model selection, we determined which parameters provided the best estimate of proboscis length. We then used coefficients to estimate the relationship between intertegular distance and proboscis length, while also considering family. Using allometric equations with an estimation for a scaling coefficient between intertegular distance and proboscis length and coefficients for each family, we explain 91% of the variance in species-level means for bee proboscis length among bee species. However, within species, individual-level intertegular distance was a poor predictor of individual proboscis length. To make our findings easy to use, we created an R package that allows estimation of proboscis length for individual bee species by inputting only family and intertegular distance. The R package also calculates foraging distance and body mass based on previously published equations. Thus by considering both taxonomy and intertegular distance we enable accurate estimation of an ecologically and evolutionarily important trait.

Retention and failure morphology of prefabricated posts

DEFF Research Database (Denmark)

Sahafi, Alireza; Peutzfeldt, Anne; Asmussen, Erik

2004-01-01

PURPOSE: This study evaluated the effect of cement, post material, surface treatment, and shape (1) on the retention of posts luted in the root canals of extracted human teeth and (2) on the failure morphology. MATERIALS AND METHODS: Posts of titanium alloy (ParaPost XH), glass fiber (Para...... at 37 degrees C for 7 days, retention was determined by extraction of the posts. Failure morphology of extracted posts was analyzed and quantified stereomicroscopically. RESULTS: Type of luting cement, post material, and shape of post influenced the retention and failure morphology of the posts. Because...

Nanoscale Morphology of Doctor Bladed versus Spin-Coated Organic Photovoltaic Films

KAUST Repository

Pokuri, Balaji Sesha Sarath

2017-08-17

Recent advances in efficiency of organic photovoltaics are driven by judicious selection of processing conditions that result in a “desired” morphology. An important theme of morphology research is quantifying the effect of processing conditions on morphology and relating it to device efficiency. State-of-the-art morphology quantification methods provide film-averaged or 2D-projected features that only indirectly correlate with performance, making causal reasoning nontrivial. Accessing the 3D distribution of material, however, provides a means of directly mapping processing to performance. In this paper, two recently developed techniques are integrated—reconstruction of 3D morphology and subsequent conversion into intuitive morphology descriptors —to comprehensively image and quantify morphology. These techniques are applied on films generated by doctor blading and spin coating, additionally investigating the effect of thermal annealing. It is found that morphology of all samples exhibits very high connectivity to electrodes. Not surprisingly, thermal annealing consistently increases the average domain size in the samples, aiding exciton generation. Furthermore, annealing also improves the balance of interfaces, enhancing exciton dissociation. A comparison of morphology descriptors impacting each stage of photophysics (exciton generation, dissociation, and charge transport) reveals that spin-annealed sample exhibits superior morphology-based performance indicators. This suggests substantial room for improvement of blade-based methods (process optimization) for morphology tuning to enhance performance of large area devices.

The ecological importance of intraspecific variation.

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Des Roches, Simone; Post, David M; Turley, Nash E; Bailey, Joseph K; Hendry, Andrew P; Kinnison, Michael T; Schweitzer, Jennifer A; Palkovacs, Eric P

2018-01-01

Human activity is causing wild populations to experience rapid trait change and local extirpation. The resulting effects on intraspecific variation could have substantial consequences for ecological processes and ecosystem services. Although researchers have long acknowledged that variation among species influences the surrounding environment, only recently has evidence accumulated for the ecological importance of variation within species. We conducted a meta-analysis comparing the ecological effects of variation within a species (intraspecific effects) with the effects of replacement or removal of that species (species effects). We evaluated direct and indirect ecological responses, including changes in abundance (or biomass), rates of ecological processes and changes in community composition. Our results show that intraspecific effects are often comparable to, and sometimes stronger than, species effects. Species effects tend to be larger for direct ecological responses (for example, through consumption), whereas intraspecific effects and species effects tend to be similar for indirect responses (for example, through trophic cascades). Intraspecific effects are especially strong when indirect interactions alter community composition. Our results summarize data from the first generation of studies examining the relative ecological effects of intraspecific variation. Our conclusions can help inform the design of future experiments and the formulation of strategies to quantify and conserve biodiversity.

Morphology and ecological characteristics of Sparganium × longifolium (Typhaceae in the Central part of European Russia

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E. A. Belyakov

2017-05-01

Full Text Available The increasing impact of anthropogenic factors and climate change affect the growth of a number of taxa of hybrid nature. These taxa are widespread among various taxonomic groups of aquatic and semi-aquatic plants. The genus Sparganium L. В is not an exception. In that regard, the aim of this study is to conduct biomorphological investigation of Sparganium × longifolium Turcz. ex Ledeb., evaluate qualitative and quantitative criteria for the hybrid similarities and differences with its parental species, as well as to analyze data on its habitat characteristics. Samples were collected in 2014–2016 from waterbodies in European Russia (Tver and Yaroslavl oblasts. In the study on biomorphology of S. × longifolium we used live and fixed materials, as well as herbarium funds of IBIW, MXA and MW. To establish and specify taxonomic features of the hybrid under study, indicating to its similarity with a certain ancestral species, our data on the morphology and ecology of S. emersum Rehm. and S. gramineum Georgi. are used. During field studies, the type of water object where the hybrid was detected, ecological characteristics of its habitat (type of soil, depth, water temperature and pH are determined; the list of taxa which enter into the cenosis composition is compiled. The biomorphological investigation of S. × longifolium shows that by life form this hybrid, as well as its parental species, is a vegetative-mobile evidently-polycentric annual or biennial plant of vegetative origin with a racemose root system. The following should be attributed to the characteristic features justifying the hybrid origin of S. × longifolium: 1 a wider, slightly carinated lamina (as in S. emersum; 2 a branched inflorescence (as in S. gramineum; 3 the lower covering leaf of inflorescence, often exceeding the total length of the latter; 4 fruits with a straight (as in S. emersum as well as bent (as in S. gramineum style. Interestingly, some populations of S. �

Nematode taxonomy: from morphology to metabarcoding

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Ahmed, M.; Sapp, M.; Prior, T.; Karssen, G.; Back, M.

2015-11-01

Nematodes represent a species rich and morphologically diverse group of metazoans inhabiting both aquatic and terrestrial environments. Their role as biological indicators and as key players in nutrient cycling has been well documented. Some groups of nematodes are also known to cause significant losses to crop production. In spite of this, knowledge of their diversity is still limited due to the difficulty in achieving species identification using morphological characters. Molecular methodology has provided very useful means of circumventing the numerous limitations associated with classical morphology based identification. We discuss herein the history and the progress made within the field of nematode systematics, the limitations of classical taxonomy and how the advent of high throughput sequencing is facilitating advanced ecological and molecular studies.

Quantifying uncertainty and trade-offs in resilience assessments

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Craig R. Allen

2018-03-01

Full Text Available Several frameworks have been developed to assess the resilience of social-ecological systems, but most require substantial data inputs, time, and technical expertise. Stakeholders and practitioners often lack the resources for such intensive efforts. Furthermore, most end with problem framing and fail to explicitly address trade-offs and uncertainty. To remedy this gap, we developed a rapid survey assessment that compares the relative resilience of social-ecological systems with respect to a number of resilience properties. This approach generates large amounts of information relative to stakeholder inputs. We targeted four stakeholder categories: government (policy, regulation, management, end users (farmers, ranchers, landowners, industry, agency/public science (research, university, extension, and NGOs (environmental, citizen, social justice in four North American watersheds, to assess social-ecological resilience through surveys. Conceptually, social-ecological systems are comprised of components ranging from strictly human to strictly ecological, but that relate directly or indirectly to one another. They have soft boundaries and several important dimensions or axes that together describe the nature of social-ecological interactions, e.g., variability, diversity, modularity, slow variables, feedbacks, capital, innovation, redundancy, and ecosystem services. There is no absolute measure of resilience, so our design takes advantage of cross-watershed comparisons and therefore focuses on relative resilience. Our approach quantifies and compares the relative resilience across watershed systems and potential trade-offs among different aspects of the social-ecological system, e.g., between social, economic, and ecological contributions. This approach permits explicit assessment of several types of uncertainty (e.g., self-assigned uncertainty for stakeholders; uncertainty across respondents, watersheds, and subsystems, and subjectivity in

Quantifying the Impacts of Outlet Control Structures on Lake Hydrology and Ecology

Science.gov (United States)

Budd, B. M.; Kendall, A. D.; Martin, S. L.; Hyndman, D. W.

2012-12-01

There have been limited studies of the impacts of lake level control structures on stream ecology and lake property erosion. We examine the influence of historical lake level management strategies on Higgins Lake in Michigan, which is regionally known for recreation, fisheries, and scenery. Lake control structures have potentially increased shoreline erosion and seasonally-reduced flow through the outlets, likely impacting fish habitat. Concerns over these issues spurred local land owners to seek a study on the possible hydrologic and ecological impacts of the removal or modification of the control structure. Bathymetry maps are fundamental to understanding and managing lake ecosystems. From the 1930's through the 1950's, these maps were developed for thousands of Michigan inland lakes using soundings lowered through holes cut in winter lake ice. Increased land use change and alterations of lake outlets have likely modified erosion and sedimentation rates of these lake systems. Our research includes bathymetry surveys of Higgins Lake using an Acoustic Doppler Current Profiler (ADCP) and side-scan sonar. The new higher-resolution bathymetry serves as the basis for simulating impacts of potential changes in lake management, on a verity of inpoint including shoreline position and fish habitat.

Quantifying carbon stores and decomposition in dead wood: A review

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Matthew B. Russell; Shawn Fraver; Tuomas Aakala; Jeffrey H. Gove; Christopher W. Woodall; Anthony W. D’Amato; Mark J. Ducey

2015-01-01

The amount and dynamics of forest dead wood (both standing and downed) has been quantified by a variety of approaches throughout the forest science and ecology literature. Differences in the sampling and quantification of dead wood can lead to differences in our understanding of forests and their role in the sequestration and emissions of CO2, as...

Ecological, morphological, and histological studies on Blaps polycresta (Coleoptera: Tenebrionidae) as biomonitors of cadmium soil pollution.

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Osman, Wafaa; El-Samad, Lamia M; Mokhamer, El-Hassan; El-Touhamy, Aya; Shonouda, Mourad

2015-09-01

Soil pollution in Egypt became far more serious than before due to either the heavy usage of different toxic pesticides or aerosol deposition of industrial pollutants. The present mentioned ground beetle, Blaps polycresta Tschinkel 1975 (Coleoptera: Tenebrionidae), showed ecological, morphological, and histological alterations in adult insects as biomonitors. Two cultivated sites (reference and polluted) were chosen for sampling the insects. The results indicated a significant increase in soil cadmium concentration of the polluted site leading to sex-specific difference in cadmium accumulation in gonads and alimentary canal of insects that being higher in males than females. The cadmium pollution leads significantly to a decrease in population density, a reduction in body weight, an increase in mortality rate, and an increase in sex ratio of the insects. The results also revealed a striking decrease in body length of the polluted insects with a marked increase in the percentage of deformed gonads and alimentary canal of both sexes. Some histopathological alterations were also recorded in testis, ovary, and midgut of the polluted insects. Our results confirmed that beetles are a good bioindicator for soil pollution, and the different studied parameters could be easily employed as sensitive monitors for cadmium soil pollution.

Quantifying Physiological, Behavioral and Ecological Consequences of Hypoxic Events in Kelp Forest

Science.gov (United States)

Litvin, S. Y.; Beers, J. M.; Woodson, C. B.; Leary, P.; Fringer, O. B.; Goldbogen, J. A.; Micheli, F.; Monismith, S. G.; Somero, G. N.

2016-02-01

Rocky reef kelp forests that extend along the coast of central California, like many habitats in upwelling systems, often experience inundations of low dissolved oxygen (DO) or hypoxic waters. These events have the potential to influence the structure and function of coastal ecosystems. The ecological consequences of hypoxia for these systems will be mediated by physiological thresholds and behavioral responses of resident organisms in the context of the spatial and temporal variability of DO, and other potential stressors. Our research focuses on Sebastes (i.e. rockfish) because of their commercial, recreational and ecological importance, high abundance across near shore habitats and the potentially severe impacts of physiological stress due to hypoxia. In the lab, to investigate how hypoxic events physiologically effect rockfish, we exposed young of the year (YOY) of 5 species and two life stages of blue rockfish, S. mystinus (YOY and 1+), to DO concentrations representative of upwelling conditions and measured a suite of whole organisms and tissue level responses including metabolic rate, ventilation, tissue-level metabolism, and blood biochemistry. Results demonstrate species and life stage specific differences in physiological stress under upwelling driven hypoxic conditions and suggest YOY rockfishes may currently be living near their physiological limits. In the laboratory we further explored if physiological impacts result in behavioral consequences by examining the startle response of YOY rockfish, a relative measure of predator avoidance ability, under a range of DO concentrations and exposure durations. To further explore behavioral responses of rockfish to low in DO within the kelp forest we are using two approaches, monitoring the vertical distribution of fish communities across the water column using an acoustic imaging camera (ARIS 3000, Soundmetrics Inc.) and acoustic tagging, with 3-D positioning ability (VPS, VEMCO Inc.), of larger blue rockfish

Beyond neutral and forbidden links: morphological matches and the assembly of mutualistic hawkmoth-plant networks.

Science.gov (United States)

Sazatornil, Federico D; Moré, Marcela; Benitez-Vieyra, Santiago; Cocucci, Andrea A; Kitching, Ian J; Schlumpberger, Boris O; Oliveira, Paulo E; Sazima, Marlies; Amorim, Felipe W

2016-11-01

A major challenge in evolutionary ecology is to understand how co-evolutionary processes shape patterns of interactions between species at community level. Pollination of flowers with long corolla tubes by long-tongued hawkmoths has been invoked as a showcase model of co-evolution. Recently, optimal foraging models have predicted that there might be a close association between mouthparts' length and the corolla depth of the visited flowers, thus favouring trait convergence and specialization at community level. Here, we assessed whether hawkmoths more frequently pollinate plants with floral tube lengths similar to their proboscis lengths (morphological match hypothesis) against abundance-based processes (neutral hypothesis) and ecological trait mismatches constraints (forbidden links hypothesis), and how these processes structure hawkmoth-plant mutualistic networks from five communities in four biogeographical regions of South America. We found convergence in morphological traits across the five communities and that the distribution of morphological differences between hawkmoths and plants is consistent with expectations under the morphological match hypothesis in three of the five communities. In the two remaining communities, which are ecotones between two distinct biogeographical areas, interactions are better predicted by the neutral hypothesis. Our findings are consistent with the idea that diffuse co-evolution drives the evolution of extremely long proboscises and flower tubes, and highlight the importance of morphological traits, beyond the forbidden links hypothesis, in structuring interactions between mutualistic partners, revealing that the role of niche-based processes can be much more complex than previously known. © 2016 The Authors. Journal of Animal Ecology © 2016 British Ecological Society.

An inventory of continental U.S. terrestrial candidate ecological restoration areas based on landscape context

Science.gov (United States)

James Wickham; Kurt Riitters; Peter Vogt; Jennifer Costanza; Anne Neale

2017-01-01

Landscape context is an important factor in restoration ecology, but the use of landscape context for site prioritization has not been as fully developed.We used morphological image processing to identify candidate ecological restoration areas based on their proximity to existing natural vegetation. We identified 1,102,720 candidate ecological restoration areas across...

Habitat-specific morphological variation among threespine sticklebacks (Gasterosteus aculeatus within a drainage basin.

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Mike M Webster

Full Text Available Habitat-specific morphological variation, often corresponding to resource specialization, is well documented in freshwater fishes. In this study we used landmark based morphometric analyses to investigate morphological variation among threespine sticklebacks (Gasterosteus aculeatus L. from four interconnected habitat types within a single lowland drainage basin in eastern England. These included the upper and lower reaches of the river, the estuary, a connected ditch network and a coastal salt marsh. We found significant habitat-specific differences in morphology, with three axes of variation describing differences in orbit diameter, body depth, caudal peduncle shape and pectoral fin positioning as well as variation in relative dorsal and pelvic spine size. Interestingly, the ditch system, an artificial and heavily managed habitat, is populated by sticklebacks with a characteristic morphology, suggesting that human management of habitats can in some circumstances lead to morphological variation among the animals that inhabit them. We discuss the mechanisms that conceivably underlie the observed morphological variation and the further work necessary to identify them. Finally, we consider the implications of habitat-specific body shape variation for the behavioural ecology of this ecologically generalist species.

Habitat-Specific Morphological Variation among Threespine Sticklebacks (Gasterosteus aculeatus) within a Drainage Basin

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Webster, Mike M.; Atton, Nicola; Hart, Paul J. B.; Ward, Ashley J. W.

2011-01-01

Habitat-specific morphological variation, often corresponding to resource specialization, is well documented in freshwater fishes. In this study we used landmark based morphometric analyses to investigate morphological variation among threespine sticklebacks (Gasterosteus aculeatus L.) from four interconnected habitat types within a single lowland drainage basin in eastern England. These included the upper and lower reaches of the river, the estuary, a connected ditch network and a coastal salt marsh. We found significant habitat-specific differences in morphology, with three axes of variation describing differences in orbit diameter, body depth, caudal peduncle shape and pectoral fin positioning as well as variation in relative dorsal and pelvic spine size. Interestingly, the ditch system, an artificial and heavily managed habitat, is populated by sticklebacks with a characteristic morphology, suggesting that human management of habitats can in some circumstances lead to morphological variation among the animals that inhabit them. We discuss the mechanisms that conceivably underlie the observed morphological variation and the further work necessary to identify them. Finally, we consider the implications of habitat-specific body shape variation for the behavioural ecology of this ecologically generalist species. PMID:21698269

Parallel ecological networks in ecosystems

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Olff, Han; Alonso, David; Berg, Matty P.; Eriksson, B. Klemens; Loreau, Michel; Piersma, Theunis; Rooney, Neil

2009-01-01

In ecosystems, species interact with other species directly and through abiotic factors in multiple ways, often forming complex networks of various types of ecological interaction. Out of this suite of interactions, predator–prey interactions have received most attention. The resulting food webs, however, will always operate simultaneously with networks based on other types of ecological interaction, such as through the activities of ecosystem engineers or mutualistic interactions. Little is known about how to classify, organize and quantify these other ecological networks and their mutual interplay. The aim of this paper is to provide new and testable ideas on how to understand and model ecosystems in which many different types of ecological interaction operate simultaneously. We approach this problem by first identifying six main types of interaction that operate within ecosystems, of which food web interactions are one. Then, we propose that food webs are structured among two main axes of organization: a vertical (classic) axis representing trophic position and a new horizontal ‘ecological stoichiometry’ axis representing decreasing palatability of plant parts and detritus for herbivores and detrivores and slower turnover times. The usefulness of these new ideas is then explored with three very different ecosystems as test cases: temperate intertidal mudflats; temperate short grass prairie; and tropical savannah. PMID:19451126

Extreme morphologies of mantis shrimp larvae

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Carolin Haug

Full Text Available ABSTRACT Larvae of stomatopods (mantis shrimps are generally categorized into four larval types: antizoea, pseudozoea (both representing early larval stages, alima and erichthus (the latter two representing later larval stages. These categories, however, do not reflect the existing morphological diversity of stomatopod larvae, which is largely unstudied. We describe here four previously unknown larval types with extreme morphologies. All specimens were found in the collections of the Zoological Museum, University of Copenhagen and were collected during the Danish Dana Expedition round the world 1928-30. These new larval types all represent erichthus-type larvae, especially differing in their shield morphologies. The shield morphology ranges from almost spherical to rather disc-like, with sometimes extremely elongated spines, but only a general systematic assignment of the larvae was possible. Further investigations of these larvae are crucial to understand their life habits and ecological impact, especially as stomatopod and other crustacean larvae might have a much more important position in the marine ecosystems than their corresponding adults.

Ecology and Education in Landscape Architecture

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James Miller

2004-06-01

Full Text Available Landscape architects engage in a wide range of projects relating to environmental quality. Indeed, the goals of preserving biodiversity and maintaining the integrity of ecological function is implicit in the charters of several of the discipline's professional organisations. Nonetheless, there is widespread opinion that much of the potential of design to contribute to environmental solutions goes unrealised. There are numerous explanations that purport to account for this situation; in this paper, we focus on one, the assertion that degree programmes in landscape architecture generally do a poor job of preparing students for practice grounded in ecological awareness. We examined the validity of this assertion by quantifying the amount and form of ecology-based coursework required of landscape architecture students. We surveyed the curricula of all 63 accredited, first-professional degree programmes in North America (28 offering a BLA, 17 offering an MLA and 18 offering both. We focused on required courses that could be categorised as emphasising information-based ecology, ecology/design integration, or plant identification and ecology. We recorded the level (introductory or advanced and number of credit hours for each course, and the total number of credits required for graduation in each programme. Thirty-seven undergraduate programmes required an introductory information-based ecology course. Only 13 required an advanced class in ecology and, of these, only three required coursework in landscape ecology. All of the undergraduate programmes except one required a plant class. Ten of the graduate programmes required an information-based class, an advanced, except one. Six required a course in landscape ecology. Eight required at least one ecology-design integration course, yet had no requirements regarding information-based courses. Thirty graduate programmes required at least one plant course. We discuss the implications of these results and

Patterns of cranial ontogeny in lacertid lizards: morphological and allometric disparity.

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Urošević, A; Ljubisavljević, K; Ivanović, A

2013-02-01

We explored the ontogenetic dynamics of the morphological and allometric disparity in the cranium shapes of twelve lacertid lizard species. The analysed species (Darevskia praticola, Dinarolacerta mosorensis, Iberolacerta horvathi, Lacerta agilis, L. trilineata, L. viridis, Podarcis erhardii, P. melisellensis, P. muralis, P. sicula, P. taurica and Zootoca vivipara) can be classified into different ecomorphs: terrestrial lizards that inhabit vegetated habitats (habitats with lush or sparse vegetation), saxicolous and shrub-climbing lizards. We observed that there was an overall increase in the morphological disparity (MD) during the ontogeny of the lacertid lizards. The ventral cranium, which is involved in the mechanics of jaw movement and feeding, showed higher levels of MD, an ontogenetic shift in the morphospace planes and more variable allometric patterns than more conserved dorsal crania. With respect to ecology, the allometric trajectories of the shrub-climbing species tended to cluster together, whereas the allometric trajectories of the saxicolous species were highly dispersed. Our results indicate that the ontogenetic patterns of morphological and allometric disparity in the lacertid lizards are modified by ecology and functional constraints and that the identical mechanisms that lead to intraspecific morphological variation also produce morphological divergence at higher taxonomic levels. © 2012 The Authors. Journal of Evolutionary Biology © 2012 European Society For Evolutionary Biology.

The morphology of the inner ear of squamate reptiles and its bearing on the origin of snakes

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Palci, Alessandro; Hutchinson, Mark N.; Caldwell, Michael W.; Lee, Michael S. Y.

2017-08-01

The inner ear morphology of 80 snake and lizard species, representative of a range of ecologies, is here analysed and compared to that of the fossil stem snake Dinilysia patagonica, using three-dimensional geometric morphometrics. Inner ear morphology is linked to phylogeny (we find here a strong phylogenetic signal in the data that can complicate ecological correlations), but also correlated with ecology, with Dinilysia resembling certain semi-fossorial forms (Xenopeltis and Cylindrophis), consistent with previous reports. We here also find striking resemblances between Dinilysia and some semi-aquatic snakes, such as Myron (Caenophidia, Homalopsidae). Therefore, the inner ear morphology of Dinilysia is consistent with semi-aquatic as well as semi-fossorial habits: the most similar forms are either semi-fossorial burrowers with a strong affinity to water (Xenopeltis and Cylindrophis) or amphibious, intertidal forms which shelter in burrows (Myron). Notably, Dinilysia does not cluster as closely with snakes with exclusively terrestrial or obligate burrowing habits (e.g. scolecophidians and uropeltids). Moreover, despite the above similarities, Dinilysia also occupies a totally unique morphospace, raising issues with linking it with any particular ecological category.

Ecological approach in constructing residential areas

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Bogdanović Ružica

2004-01-01

Full Text Available As a concept sustainable development has evolved over the past two decades from a concept closely associated with the biophysical environment to become much more complex, embracing social, cultural, economic political and esthetic phenomenon, which are invariably in mutual interaction, so they influence sustainability of natural environment. The very notion of "sustainable" we are meeting today in almost all significance areas of human activities. Contemporary planning, projecting and building techniques undoubtedly implied integration of goals of environmental prevention with goals of socio-economic development, all with respecting the esthetic standards. This paper represents experience from foreign praxis. Project defines and resolves objectives from social, economical, morphological and ecological aspects. Most important is aspect of Ecological Optimisation, which consists of main components: energy use optimization, water concept, exemplary waste management concept and ecological soil management.

Imbalance in individual researcher's peer review activities quantified for four British Ecological Society journals, 2003-2010.

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Petchey, Owen L; Fox, Jeremy W; Haddon, Lindsay

2014-01-01

Researchers contribute to the scientific peer review system by providing reviews, and "withdraw" from it by submitting manuscripts that are subsequently reviewed. So far as we are aware, there has been no quantification of the balance of individual's contributions and withdrawals. We compared the number of reviews provided by individual researchers (i.e., their contribution) to the number required by their submissions (i.e. their withdrawals) in a large and anonymised database provided by the British Ecological Society. The database covered the Journal of Ecology, Journal of Animal Ecology, Journal of Applied Ecology, and Functional Ecology from 2003-2010. The majority of researchers (64%) did not have balanced contributions and withdrawals. Depending on assumptions, 12% to 44% contributed more than twice as much as required; 20% to 52% contributed less than half as much as required. Balance, or lack thereof, varied little in relation to the number of years a researcher had been active (reviewing or submitting). Researchers who contributed less than required did not lack the opportunity to review. Researchers who submitted more were more likely to accept invitations to review. These finding suggest overall that peer review of the four analysed journals is not in crisis, but only due to the favourable balance of over- and under-contributing researchers. These findings are limited to the four journals analysed, and therefore cannot include researcher's other peer review activities, which if included might change the proportions reported. Relatively low effort was required to assemble, check, and analyse the data. Broader analyses of individual researcher's peer review activities would contribute to greater quality, efficiency, and fairness in the peer review system.

Why do morphological phylogenies vary in quality? An investigation based on the comparative history of lizard clades.

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Arnold, E N

1990-05-22

Phylogenies based on morphology vary considerably in their quality: some are robust and explicit with little conflict in the data set, whereas others are far more tenuous, with much conflict and many possible alternatives. The main primary reasons for untrue or inexplicit morphological phylogenies are: not enough characters developed between branching points, uncertain character polarity, poorly differentiated character states, homoplasy caused by parallelism or reversal, and extinction, which may remove species entirely from consideration and can make originally conflicting data sets misleadingly compatible, increasing congruence at the expense of truth. Extinction differs from other confounding factors in not being apparent either in the data set or in subsequent analysis. One possibility is that variation in the quality of morphological phylogenies has resulted from exposure to different ecological situations. To investigate this, it is necessary to compare the histories of the clades concerned. In the case of explicit morphological phylogenies, ecological and behavioural data can be integrated with them and it may then be possible to decide whether morphological characters are likely to have been elicited by the environments through which the clade has passed. The credibility of such results depends not only on the phylogeny being robust but also on its detailed topology: a pectinate phylogeny will often allow more certain and more explicit statements to be made about historical events. In the case of poor phylogenies, it is not possible to produce detailed histories, but they can be compared with robust phylogenies in the range of ecological situations occupied, and whether they occupy novel situations in comparison with their outgroups. LeQuesne testing can give information about niche homoplasy, and it may also be possible to see if morphological features are functionally associated with ecological parameters, even if the direction of change is unknown

Where to restore ecological connectivity? Detecting barriers and quantifying restoration benefits.

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Brad H McRae

Full Text Available Landscape connectivity is crucial for many ecological processes, including dispersal, gene flow, demographic rescue, and movement in response to climate change. As a result, governmental and non-governmental organizations are focusing efforts to map and conserve areas that facilitate movement to maintain population connectivity and promote climate adaptation. In contrast, little focus has been placed on identifying barriers-landscape features which impede movement between ecologically important areas-where restoration could most improve connectivity. Yet knowing where barriers most strongly reduce connectivity can complement traditional analyses aimed at mapping best movement routes. We introduce a novel method to detect important barriers and provide example applications. Our method uses GIS neighborhood analyses in conjunction with effective distance analyses to detect barriers that, if removed, would significantly improve connectivity. Applicable in least-cost, circuit-theoretic, and simulation modeling frameworks, the method detects both complete (impermeable barriers and those that impede but do not completely block movement. Barrier mapping complements corridor mapping by broadening the range of connectivity conservation alternatives available to practitioners. The method can help practitioners move beyond maintaining currently important areas to restoring and enhancing connectivity through active barrier removal. It can inform decisions on trade-offs between restoration and protection; for example, purchasing an intact corridor may be substantially more costly than restoring a barrier that blocks an alternative corridor. And it extends the concept of centrality to barriers, highlighting areas that most diminish connectivity across broad networks. Identifying which modeled barriers have the greatest impact can also help prioritize error checking of land cover data and collection of field data to improve connectivity maps. Barrier detection

Cloning nanocrystal morphology with soft templates

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Thapa, Dev Kumar; Pandey, Anshu

2016-08-01

In most template directed preparative methods, while the template decides the nanostructure morphology, the structure of the template itself is a non-general outcome of its peculiar chemistry. Here we demonstrate a template mediated synthesis that overcomes this deficiency. This synthesis involves overgrowth of silica template onto a sacrificial nanocrystal. Such templates are used to copy the morphologies of gold nanorods. After template overgrowth, gold is removed and silver is regrown in the template cavity to produce a single crystal silver nanorod. This technique allows for duplicating existing nanocrystals, while also providing a quantifiable breakdown of the structure - shape interdependence.

Baseline ecological footprint of Sandia National Laboratories, New Mexico.

Energy Technology Data Exchange (ETDEWEB)

Coplen, Amy K.; Mizner, Jack Harry,; Ubechel, Norion M.

2009-01-01

The Ecological Footprint Model is a mechanism for measuring the environmental effects of operations at Sandia National Laboratories in Albuquerque, New Mexico (SNL/NM). This analysis quantifies environmental impact associated with energy use, transportation, waste, land use, and water consumption at SNL/NM for fiscal year 2005 (FY05). Since SNL/NMs total ecological footprint (96,434 gha) is greater than the waste absorption capacity of its landholdings (338 gha), it created an ecological deficit of 96,096 gha. This deficit is equal to 886,470lha, or about 3,423 square miles of Pinyon-Juniper woodlands and desert grassland. 89% of the ecological footprint can be attributed to energy use, indicating that in order to mitigate environmental impact, efforts should be focused on energy efficiency, energy reduction, and the incorporation of additional renewable energy alternatives at SNL/NM.

A fully automated cell segmentation and morphometric parameter system for quantifying corneal endothelial cell morphology.

Science.gov (United States)

Al-Fahdawi, Shumoos; Qahwaji, Rami; Al-Waisy, Alaa S; Ipson, Stanley; Ferdousi, Maryam; Malik, Rayaz A; Brahma, Arun

2018-07-01

Corneal endothelial cell abnormalities may be associated with a number of corneal and systemic diseases. Damage to the endothelial cells can significantly affect corneal transparency by altering hydration of the corneal stroma, which can lead to irreversible endothelial cell pathology requiring corneal transplantation. To date, quantitative analysis of endothelial cell abnormalities has been manually performed by ophthalmologists using time consuming and highly subjective semi-automatic tools, which require an operator interaction. We developed and applied a fully-automated and real-time system, termed the Corneal Endothelium Analysis System (CEAS) for the segmentation and computation of endothelial cells in images of the human cornea obtained by in vivo corneal confocal microscopy. First, a Fast Fourier Transform (FFT) Band-pass filter is applied to reduce noise and enhance the image quality to make the cells more visible. Secondly, endothelial cell boundaries are detected using watershed transformations and Voronoi tessellations to accurately quantify the morphological parameters of the human corneal endothelial cells. The performance of the automated segmentation system was tested against manually traced ground-truth images based on a database consisting of 40 corneal confocal endothelial cell images in terms of segmentation accuracy and obtained clinical features. In addition, the robustness and efficiency of the proposed CEAS system were compared with manually obtained cell densities using a separate database of 40 images from controls (n = 11), obese subjects (n = 16) and patients with diabetes (n = 13). The Pearson correlation coefficient between automated and manual endothelial cell densities is 0.9 (p system, and the possibility of utilizing it in a real world clinical setting to enable rapid diagnosis and for patient follow-up, with an execution time of only 6 seconds per image. Copyright © 2018 Elsevier B.V. All rights reserved.

On the methodology of feeding ecology in fish

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Saikia Surjya Kumar

2016-06-01

Full Text Available Feeding ecology explains predator’s preference to some preys over others in their habitat and their competitions thereof. The subject, as a functional and applied biology, is highly neglected, and in case of fish, a uniform and consistent methodology is absent. The currently practiced methods are largely centred on mathematical indices and highly erroneous because of non-uniform outcomes. Therefore, it requires a relook into the subject to elucidate functional contributions and to make it more comparable and comprehensive science. In this article, approachable methodological strategies have been forwarded in three hierarchical steps, namely, food occurrence, feeding biology and interpretative ecology. All these steps involve wide ranges of techniques, within the scope of ecology but not limited to, and traverse from narrative to functional evolutionary ecology. The first step is an assumption-observation practice to assess food of fish, followed by feeding biology that links morphological, histological, cytological, bacteriological or enzymological correlations to preferred food in the environment. Interpretative ecology is the higher level of analysis in which the outcomes are tested and discussed against evolutionary theories. A description of possible pedagogics on the methods of feeding ecological studies has also been forwarded.

The ecological - Societal underpinnings of Everglades restoration

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Sklar, Fred H.; Chimney, M.J.; Newman, S.; McCormick, P.; Gawlik, D.; Miao, S.; McVoy, C.; Said, W.; Newman, J.; Coronado, C.; Crozier, G.; Korvela, M.; Rutchey, K.

2005-01-01

The biotic integrity of the Florida Everglades, a wetland of immense international importance, is threatened as a result of decades of human manipulation for drainage and development. Past management of the system only exacerbated the problems associated with nutrient enrichment and disruption of regional hydrology. The Comprehensive Everglades Restoration Plan (CERP) now being implemented by Federal and State governments is an attempt to strike a balance between the needs of the environment with the complex management of water and the seemingly unbridled economic growth of southern Florida. CERP is expected to reverse negative environmental trends by "getting the water right", but successful Everglades restoration will require both geochemical and hydrologic intervention on a massive scale. This will produce ecological trade-offs and will require new and innovative scientific measures to (1) reduce total phosphorus concentrations within the remaining marsh to 10 ??g/L or lower; (2) quantify and link ecological benefits to the restoration of depths, hydroperiods, and flow velocities; and (3) compensate for ecological, economic, and hydrologic uncertainties in the CERP through adaptive management. ?? The Ecological Society of America.

Exploring dust emission responses to land cover change using an ecological land classification

Science.gov (United States)

Galloza, Magda S.; Webb, Nicholas P.; Bleiweiss, Max P.; Winters, Craig; Herrick, Jeffrey E.; Ayers, Eldon

2018-06-01

Despite efforts to quantify the impacts of land cover change on wind erosion, assessment uncertainty remains large. We address this uncertainty by evaluating the application of ecological site concepts and state-and-transition models (STMs) for detecting and quantitatively describing the impacts of land cover change on wind erosion. We apply a dust emission model over a rangeland study area in the northern Chihuahuan Desert, New Mexico, USA, and evaluate spatiotemporal patterns of modelled horizontal sediment mass flux and dust emission in the context of ecological sites and their vegetation states; representing a diversity of land cover types. Our results demonstrate how the impacts of land cover change on dust emission can be quantified, compared across land cover classes, and interpreted in the context of an ecological model that encapsulates land management intensity and change. Results also reveal the importance of established weaknesses in the dust model soil characterisation and drag partition scheme, which appeared generally insensitive to the impacts of land cover change. New models that address these weaknesses, coupled with ecological site concepts and field measurements across land cover types, could significantly reduce assessment uncertainties and provide opportunities for identifying land management options.

Quantifying spatially derived carrying capacity occupation: Framework for characterisation modelling and application to terrestrial acidification

DEFF Research Database (Denmark)

Bjørn, Anders; Margni, M.; Bulle, C.

*year. This metric resembles that of the ecological footprint method and may be compared to the availability of land or water. The framework was applied to the terrestrial acidification impact category. The geochemical steady-state model PROFILE was used to quantify carrying capacities as deposition levels......The popularity of the ecological footprint method and the planetary boundaries concept shows an increasing interest among decision makers in comparing environmental impacts to carrying capacities of natural systems. Recently carrying capacity-based normalisation references were developed for impact...

Relationships between morphology, diet and spatial distribution: testing the effects of intra and interspecific morphological variations on the patterns of resource use in two Neotropical Cichlids

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Ana Lúcia A. Sampaio

Full Text Available Considering th e morphology, diet and spatial distribution of Satanoperca pappaterraand Crenicichla britskii (Perciformes: Cichlidae in the Upper Paraná River floodplain (Brazil, the following questions were investigated: (1 Could the body shape predict the use of trophic resources and habitat by C. britskiiand S. pappaterra? (2 Could the relationship between morphology and use of trophic resources and habitat be also extended to the intraspecific scale? (3 What are the most important morphological traits used to predict the variation on diet and habitat occupation within and between species? We hypothesized that intra and interspecific differences in morphological patterns imply in different forms of resource exploitation and that the ecomorphological analysis enables the identification of trophic and spatial niche segregation. Fish samplings were performed in different types of habitats (rivers, secondary channels, connected and disconnected lagoons in the Upper Paraná River floodplain. Analyses of the stomach content was conducted to characterize the feeding patterns and twenty-two ecomorphological indices were calculated from linear morphological measurements and areas. A principal component analysis (PCA run with these indices evidenced the formation of two significant axes, revealing in the axis 1 an ecomorphological ordination according to the type of habitat, regardless the species. The individuals of both species exploiting lotic habitats tended to have morphological traits that enable rapid progressive and retrograde movements, braking and continuous swimming, whereas individuals found in lentic and semi-lotic habitats presented morphology adapted to a greater maneuverability and stabilization in deflections. On the other hand the axis 2 evidenced a segregation related to the feeding ecology, between S. pappaterra and C. britskii. The relationship between morphology and use of spatial and feeding resource was corroborated by the

Morphological and ecological variation of Gremmeniella abietina var. abietina in Pinus sylvestris, Pinus contorta and Picea abies sapling stands in northern Finland and the Kola Peninsula

Energy Technology Data Exchange (ETDEWEB)

Kaitera, Juha; Seitamaeki, Leena; Jalkanen, Risto [Finnish Forest Research Inst., Rovaniemi (Finland). Rovaniemi Research Station

2000-07-01

The morphological and ecological variation of two types of Gremmeniella abietina var. abietina causing scleroderris canker on conifers was investigated in Pinus spp. and Picea sp. sapling stands in northern Finland and the Kola Peninsula. Small-tree type (STT or B type) of G. abietina was detected alone in 13 Scots pine, three lodgepole pine and two Norway spruce sapling stands out of 26 stands investigated, both STT and large-tree type (LTT or A type) were observed in six Scots pine stands, and LTT was detected alone in two Scots pine stands. For the first time, G. abietina was found to injure Norway spruce saplings in a respective plantation in northern Fennoscandia. STT isolates produced statistically significantly more conidia in vitro than LTT isolates. Morphological variation in conidia septation revealed that STT produced conidia with more than five septa more frequently than did LTT. There was a greater range in variation in septation in STT than in LTT, with overlapping between the types. Isolates of both types were equally associated with cankers, coloured wood, pycnidia or apothecia in the infected saplings.

Using expert informed GIS to locate important marine social-ecological hotspots.

Science.gov (United States)

Mahboubi, Pouyan; Parkes, Margot; Stephen, Craig; Chan, Hing Man

2015-09-01

The marine environment provides significant benefits to many local communities. Pressure to develop coastal waterways worldwide creates an urgent need for tools to locate marine spaces that have important social or ecological values, and to quantify their relative importance. The primary objective of this study was to develop, apply and critically assess a tool to identify important social-ecological hotspots in the marine environment. The study was conducted in a typical coastal community in northern British Columbia, Canada. This expert-informed GIS, or xGIS, tool used a survey instrument to draw on the knowledge of local experts from a range of backgrounds with respect to a series of 12 social-ecological value attributes, such as biodiversity, cultural and economic values. We identified approximately 1500 polygons on marine maps and assigned relative values to them using a token distribution exercise. A series of spatial statistical analyses were performed to locate and quantify the relative social-ecological importance of marine spaces and the results were ultimately summarized in a single hotspot map of the entire study area. This study demonstrates the utility of xGIS as a useful tool for stakeholders and environmental managers engaged in the planning and management of marine resources at the local and regional levels. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Genus Cladophora Kützing (Ulvophyceae) as a Globally Distributed Ecological Engineer.

Science.gov (United States)

Zulkifly, Shahrizim B; Graham, James M; Young, Erica B; Mayer, Robert J; Piotrowski, Michael J; Smith, Izak; Graham, Linda E

2013-02-01

The green algal genus Cladophora forms conspicuous nearshore populations in marine and freshwaters worldwide, commonly dominating peri-phyton communities. As the result of human activities, including the nutrient pollution of nearshore waters, Cladophora-dominated periphyton can form nuisance blooms. On the other hand, Cladophora has ecological functions that are beneficial, but less well appreciated. For example, Cladophora has previously been characterized as an ecological engineer because its complex structure fosters functional and taxonomic diversity of benthic microfauna. Here, we review classic and recent literature concerning taxonomy, cell biology, morphology, reproductive biology, and ecology of the genus Cladophora, to examine how this alga functions to modify habitats and influence littoral biogeochemistry. We review the evidence that Cladophora supports large, diverse populations of microalgal and bacterial epiphytes that influence the cycling of carbon and other key elements, and that the high production of cellulose and hydrocarbons by Cladophora-dominated periphyton has the potential for diverse technological applications, including wastewater remediation coupled to renewable biofuel production. We postulate that well-known aspects of Cladophora morphology, hydrodynamically stable and perennial holdfasts, distinctively branched architecture, unusually large cell and sporangial size and robust cell wall construction, are major factors contributing to the multiple roles of this organism as an ecological engineer. © 2013 Phycological Society of America.

Bioinformatic and Biometric Methods in Plant Morphology

Directory of Open Access Journals (Sweden)

Surangi W. Punyasena

2014-08-01

Full Text Available Recent advances in microscopy, imaging, and data analyses have permitted both the greater application of quantitative methods and the collection of large data sets that can be used to investigate plant morphology. This special issue, the first for Applications in Plant Sciences, presents a collection of papers highlighting recent methods in the quantitative study of plant form. These emerging biometric and bioinformatic approaches to plant sciences are critical for better understanding how morphology relates to ecology, physiology, genotype, and evolutionary and phylogenetic history. From microscopic pollen grains and charcoal particles, to macroscopic leaves and whole root systems, the methods presented include automated classification and identification, geometric morphometrics, and skeleton networks, as well as tests of the limits of human assessment. All demonstrate a clear need for these computational and morphometric approaches in order to increase the consistency, objectivity, and throughput of plant morphological studies.

Ecological diversification associated with the benthic-to-pelagic transition by North American minnows.

Science.gov (United States)

Burress, E D; Holcomb, J M; Tan, M; Armbruster, J W

2017-03-01

Ecological opportunity is often regarded as a key factor that explains why diversity is unevenly distributed across life. Colonization of novel environments or adaptive zones may promote diversification. North American minnows exhibit an ancestral benthic-to-pelagic habitat shift that coincided with a burst in diversification. Here, we evaluate the phenotypic and ecological implications of this habitat shift by assessing craniofacial and dietary traits among 34 species and testing for morphology-diet covariation, convergence and adaptive optima. There were several instances of morphology-diet covariation such as correlations between mouth angle and the consumption of terrestrial insects and between relative gut length and the consumption of algae. After accounting for size and phylogenetic nonindependence, benthic species had longer heads, longer snouts, eyes positioned higher on their head, smaller mouth angles and longer digestive tracts than pelagic minnows. Benthic minnows also consumed more algae but less terrestrial insects, by volume, than pelagic minnows. Lastly, there were three distinct evolutionary regimes and more convergence in morphology and dietary characteristics than expected under a Brownian motion model of evolution. These findings indicate that colonization of the pelagic zone by minnows involved myriad phenotypic and dietary changes associated with exploitation of terrestrial subsidies. Thus, minnows exhibit phenotype-dietary covariation, an expansion of ecological roles and a burst in diversification rates in response to the ecological opportunity afforded by the colonization of a novel habitat. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

[Ecology and ecologies].

Science.gov (United States)

Valera, Luca

2011-01-01

Ecology (from the Greek words οιχοσ, "house" and λογια "study of") is the science of the "house", since it studies the environments where we live. There are three main ways of thinking about Ecology: Ecology as the study of interactions (between humans and the environment, between humans and living beings, between all living beings, etc.), Ecology as the statistical study of interactions, Ecology as a faith, or rather as a science that requires a metaphysical view. The history of Ecology shows us how this view was released by the label of "folk sense" to gain the epistemological status of science, a science that strives to be interdisciplinary. So, the aim of Ecology is to study, through a scientific methodology, the whole natural world, answering to very different questions, that arise from several fields (Economics, Biology, Sociology, Philosophy, etc.). The plurality of issues that Ecology has to face led, during the Twentieth-century, to branch off in several different "ecologies". As a result, each one of these new approaches chose as its own field a more limited and specific portion of reality.

MRI and MRS on preserved samples as a tool in fish ecology.

Science.gov (United States)

Bock, Christian; Wermter, Felizitas C; Mintenbeck, Katja

2017-05-01

Magnetic Resonance Imaging (MRI) and Magnetic Resonance Spectroscopy (MRS) gain increasing attention and importance as a tool in marine ecology. So far, studies were largely limited to morphological studies, e.g. for the creation of digital libraries. Here, the utility of MRI and MRS for ecologists is tested and exemplified using formalin preserved samples of the Antarctic silverfish, Pleuragramma antarctica. As this species lacks a swim bladder, buoyancy is attained by the deposition of large amounts of lipids that are mainly stored in subcutaneous and intermuscular lipid sacs. In this study MRI and MRS are not only used to study internal morphology, but additionally to investigate functional morphology and to measure parameters of high ecological interest. The data are compared with literature data obtained by means of traditional ecological methods. The results from this study show that MR scans are not only an alternative to histological sections (as shown before), but even allow the visualization of particular features in delicate soft tissues, such as Pleuragramma's lipid sacs. 3D rendering techniques proved to be a useful tool to study organ volumes and lipid content, which usually requires laborious chemical lipid extraction and analysis. Moreover, the application of MRS even allows for an analysis of lipids and fatty acids within lipid sacs, which wouldn't be possible using destructive methods. MRI and MRS, in particular when used in combination, have the capacity to provide useful data on parameters of high ecological relevance and thus have proven to be a highly valuable addition, if not alternative, to the classical methods. Copyright © 2016 Elsevier Inc. All rights reserved.

Shape up or ship out: migratory behaviour predicts morphology across spatial scale in a freshwater fish.

Science.gov (United States)

Chapman, Ben B; Hulthén, Kaj; Brönmark, Christer; Nilsson, P Anders; Skov, Christian; Hansson, Lars-Anders; Brodersen, Jakob

2015-09-01

1. Migration is a widespread phenomenon, with powerful ecological and evolutionary consequences. Morphological adaptations to reduce the energetic costs associated with migratory transport are commonly documented for migratory species. However, few studies have investigated whether variation in body morphology can be explained by variation in migratory strategy within a species. 2. We address this question in roach Rutilus rutilus, a partially migratory freshwater fish that migrates from lakes into streams during winter. We both compare body shape between populations that differ in migratory opportunity (open vs. closed lakes), and between individuals from a single population that vary in migratory propensity (migrants and residents from a partially migratory population). Following hydrodynamic theory, we posit that migrants should have a more shallow body depth, to reduce the costs associated with migrating into streams with higher flow conditions than the lakes the residents occupy all year round. 3. We find evidence both across and within populations to support our prediction, with individuals from open lakes and migrants from the partially migratory population having a more slender, shallow-bodied morphology than fish from closed lakes and all-year residents. 4. Our data suggest that a shallow body morphology is beneficial to migratory individuals and our study is one of the first to link migratory strategy and intraspecific variation in body shape. © 2015 The Authors. Journal of Animal Ecology © 2015 British Ecological Society.

A guideline to improve qualitative social science publishing in ecology and conservation journals

OpenAIRE

Katie Moon; Tom D. Brewer; Stephanie R. Januchowski-Hartley; Vanessa M. Adams; Deborah A. Blackman

2016-01-01

A rise in qualitative social science manuscripts published in ecology and conservation journals speaks to the growing awareness of the importance of the human dimension in maintaining and improving Earth's ecosystems. Given the rise in the quantity of qualitative social science research published in ecology and conservation journals, it is worthwhile quantifying the extent to which this research is meeting established criteria for research design, conduct, and interpretation. Through a compre...

Land-use history and contemporary management inform an ecological reference model for longleaf pine woodland understory plant communities

Science.gov (United States)

Lars A. Brudvig; John L. Orrock; Ellen I. Damschen; Cathy D. Collins; Philip G. Hahn; W. Brett Mattingly; Joseph W. Veldman; Joan L. Walker

2014-01-01

Ecological restoration is frequently guided by reference conditions describing a successfully restored ecosystem; however, the causes and magnitude of ecosystem degradation vary, making simple knowledge of reference conditions insufficient for prioritizing and guiding restoration. Ecological reference models provide further guidance by quantifying reference conditions...

Bayesian Inference of Ecological Interactions from Spatial Data

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Christopher R. Stephens

2017-11-01

Full Text Available The characterization and quantification of ecological interactions and the construction of species’ distributions and their associated ecological niches are of fundamental theoretical and practical importance. In this paper, we discuss a Bayesian inference framework, which, using spatial data, offers a general formalism within which ecological interactions may be characterized and quantified. Interactions are identified through deviations of the spatial distribution of co-occurrences of spatial variables relative to a benchmark for the non-interacting system and based on a statistical ensemble of spatial cells. The formalism allows for the integration of both biotic and abiotic factors of arbitrary resolution. We concentrate on the conceptual and mathematical underpinnings of the formalism, showing how, using the naive Bayes approximation, it can be used to not only compare and contrast the relative contribution from each variable, but also to construct species’ distributions and ecological niches based on an arbitrary variable type. We also show how non-linear interactions between distinct niche variables can be identified and the degree of confounding between variables accounted for.

Quantitative assessment of morphology, T_1_ρ, and T_2 of shoulder cartilage using MRI

International Nuclear Information System (INIS)

Nardo, Lorenzo; Carballido-Gamio, Julio; Tang, Solomon; Lai, Andrew; Krug, Roland

2016-01-01

The aim of this study was to assess the feasibility of quantifying shoulder cartilage morphology and relaxometry in a clinically feasible scan time comparing different pulse sequences and assessing their reproducibility at 3 Tesla. Three pulse sequences were compared for morphological assessments of shoulder cartilage thickness and volume (SPGR, MERGE, FIESTA), while a combined T1ρ-T2 sequence was optimized for relaxometry measurements. The shoulders of six healthy subjects were scanned twice with repositioning, and the cartilage was segmented and quantified. The degree of agreement between the three morphological sequences was assessed using Bland-Altman plots, while the morphological and relaxometry reproducibility were assessed with root-mean-square coefficients of variation (RMS-CVs) Bland-Altman plots indicated good levels of agreement between the morphological assessments of the three sequences. The reproducibility of morphological assessments yielded RMS-CVs between 4.0 and 17.7 %. All sequences correlated highly (R > 0.9) for morphologic assessments with no statistically significant differences. For relaxometry assessments of humeral cartilage, RMS-CVs of 6.4 and 10.6 % were found for T1ρ and T2, respectively. The assessment of both cartilage morphology and relaxometry is feasible in the shoulder with SPGR, humeral head, and T1ρ being the more reproducible morphological sequence, anatomic region, and quantitative sequence, respectively. (orig.)

Pelvic morphology in ischiofemoral impingement

Energy Technology Data Exchange (ETDEWEB)

Bredella, Miriam A.; Azevedo, Debora C.; Oliveira, Adriana L.; Simeone, Frank J.; Chang, Connie Y.; Torriani, Martin [Massachusetts General Hospital, Department of Radiology, Musculoskeletal Imaging and Intervention, Boston, MA (United States); Stubbs, Allston J. [Wake Forest University School of Medicine, Department of Orthopedic Surgery, Division of Sports Medicine, Winston-Salem, NC (United States)

2014-11-06

To assess MRI measures to quantify pelvic morphology that may predispose to ischiofemoral impingement (IFI). We hypothesized that patients with IFI have a wider interischial distance and an increased femoral neck angle compared with normal controls. The study was IRB-approved and complied with HIPAA guidelines. IFI was diagnosed based on clinical findings (hip or buttock pain) and ipsilateral edema of the quadratus femoris muscle on MRI. Control subjects did not report isolated hip/buttock pain and underwent MRI for surveillance of neoplasms or to exclude pelvic fractures. Two MSK radiologists measured the ischiofemoral (IF) and quadratus femoris (QF) distance, the ischial angle as a measure of inter-ischial distance, and the femoral neck angle. The quadratus femoris muscle was evaluated for edema. Groups were compared using ANOVA. Multivariate standard least-squares regression modeling was used to control for age and gender. The study group comprised 84 patients with IFI (53 ± 16 years, 73 female, 11 male) and 51 controls (52 ± 16 years, 33 female, 18 male). Thirteen out of 84 patients (15 %) had bilateral IFI. Patients with IFI had decreased IF and QF distance (p < 0.0001), increased ischial angle (p = 0.004), and increased femoral neck angle (p = 0.02) compared with controls, independent of age and gender. Patients with IFI have increased ischial and femoral neck angles compared with controls. These anatomical variations in pelvic morphology may predispose to IFI. MRI is a useful method of not only assessing the osseous and soft-tissue abnormalities associated with IFI, but also of quantifying anatomical variations in pelvic morphology that can predispose to IFI. (orig.)

Pelvic morphology in ischiofemoral impingement

International Nuclear Information System (INIS)

Bredella, Miriam A.; Azevedo, Debora C.; Oliveira, Adriana L.; Simeone, Frank J.; Chang, Connie Y.; Torriani, Martin; Stubbs, Allston J.

2015-01-01

To assess MRI measures to quantify pelvic morphology that may predispose to ischiofemoral impingement (IFI). We hypothesized that patients with IFI have a wider interischial distance and an increased femoral neck angle compared with normal controls. The study was IRB-approved and complied with HIPAA guidelines. IFI was diagnosed based on clinical findings (hip or buttock pain) and ipsilateral edema of the quadratus femoris muscle on MRI. Control subjects did not report isolated hip/buttock pain and underwent MRI for surveillance of neoplasms or to exclude pelvic fractures. Two MSK radiologists measured the ischiofemoral (IF) and quadratus femoris (QF) distance, the ischial angle as a measure of inter-ischial distance, and the femoral neck angle. The quadratus femoris muscle was evaluated for edema. Groups were compared using ANOVA. Multivariate standard least-squares regression modeling was used to control for age and gender. The study group comprised 84 patients with IFI (53 ± 16 years, 73 female, 11 male) and 51 controls (52 ± 16 years, 33 female, 18 male). Thirteen out of 84 patients (15 %) had bilateral IFI. Patients with IFI had decreased IF and QF distance (p < 0.0001), increased ischial angle (p = 0.004), and increased femoral neck angle (p = 0.02) compared with controls, independent of age and gender. Patients with IFI have increased ischial and femoral neck angles compared with controls. These anatomical variations in pelvic morphology may predispose to IFI. MRI is a useful method of not only assessing the osseous and soft-tissue abnormalities associated with IFI, but also of quantifying anatomical variations in pelvic morphology that can predispose to IFI. (orig.)

Ecological genetics of freshwater fish: a short review of the genotype–phenotype connection

Directory of Open Access Journals (Sweden)

Vidal, O.

2011-12-01

Full Text Available Molecular ecology or ecological genetics is an expanding application of population genetics which has flourished in the last two decades but it is dominated by systematic and phylogeographic studies, with relatively little emphasis on the study of the genetic basis of the process of adaptation to different ecological conditions. The relationship between genotype and adaptive phenotypes is weak because populations are often difficult to quantify and experiments are logistically challenging or unfeasible. Interestingly, in freshwater fish, studies to characterize the genetic architecture of adaptive traits are not as rare as in other vertebrate groups. In this review, we summarize the few cases where the relationship between the ecology and genetics of freshwater fish is more developed, namely the relationship between genetic markers and ecological phenotypes.

Determining patterns of variability in ecological communities: time lag analysis revisited

NARCIS (Netherlands)

Kampichler, C.; Van der Jeugd, H.P.

2013-01-01

All ecological communities experience change over time. One method to quantify temporal variation in the patterns of relative abundance of communities is time lag analysis (TLA). It uses a distance-based approach to study temporal community dynamics by regressing community dissimilarity over

Pollinators, pests, and predators: Recognizing ecological trade-offs in agroecosystems.

Science.gov (United States)

Saunders, Manu E; Peisley, Rebecca K; Rader, Romina; Luck, Gary W

2016-02-01

Ecological interactions between crops and wild animals frequently result in increases or declines in crop yield. Yet, positive and negative interactions have mostly been treated independently, owing partly to disciplinary silos in ecological and agricultural sciences. We advocate a new integrated research paradigm that explicitly recognizes cost-benefit trade-offs among animal activities and acknowledges that these activities occur within social-ecological contexts. Support for this paradigm is presented in an evidence-based conceptual model structured around five evidence statements highlighting emerging trends applicable to sustainable agriculture. The full range of benefits and costs associated with animal activities in agroecosystems cannot be quantified by focusing on single species groups, crops, or systems. Management of productive agroecosystems should sustain cycles of ecological interactions between crops and wild animals, not isolate these cycles from the system. Advancing this paradigm will therefore require integrated studies that determine net returns of animal activity in agroecosystems.

Quantifying the morphodynamics of river restoration schemes using Unmanned Aerial Vehicles (UAVs)

Science.gov (United States)

Williams, Richard; Byrne, Patrick; Gilles, Eric; Hart, John; Hoey, Trevor; Maniatis, George; Moir, Hamish; Reid, Helen; Ves, Nikolas

2017-04-01

River restoration schemes are particularly sensitive to morphological adjustment during the first set of high-flow events that they are subjected to. Quantifying elevation change associated with morphological adjustment can contribute to improved adaptive decision making to ensure river restoration scheme objectives are achieved. To date the relatively high cost, technical demands and challenging logistics associated with acquiring repeat, high-resolution topographic surveys has resulted in a significant barrier to monitoring the three-dimensional morphodynamics of river restoration schemes. The availability of low-cost, consumer grade Unmanned Aerial Vehicles that are capable of acquiring imagery for processing using Structure-from-Motion Multi-View Stereo (SfM MVS) photogrammetry has the potential to transform the survey the morphodynamics of river restoration schemes. Application guidance does, however, need to be developed to fully exploit the advances of UAV technology and SfM MVS processing techniques. In particular, there is a need to quantify the effect of the number and spatial distribution of ground targets on vertical error. This is particularly significant because vertical errors propagate when mapping morphological change, and thus determine the evidence that is available for decision making. This presentation presents results from a study that investigated how the number and spatial distribution of targets influenced vertical error, and then used the findings to determine survey protocols for a monitoring campaign that has quantified morphological change across a number of restoration schemes. At the Swindale river restoration scheme, Cumbria, England, 31 targets were distributed across a 700 m long reach and the centre of each target was surveyed using RTK-GPS. Using the targets as General Control Points (GCPs) or checkpoints, they were divided into three different spatial patterns (centre, edge and random) and used for processing images acquired

Quantifying Anthropogenic Dust Emissions

Science.gov (United States)

Webb, Nicholas P.; Pierre, Caroline

2018-02-01

Anthropogenic land use and land cover change, including local environmental disturbances, moderate rates of wind-driven soil erosion and dust emission. These human-dust cycle interactions impact ecosystems and agricultural production, air quality, human health, biogeochemical cycles, and climate. While the impacts of land use activities and land management on aeolian processes can be profound, the interactions are often complex and assessments of anthropogenic dust loads at all scales remain highly uncertain. Here, we critically review the drivers of anthropogenic dust emission and current evaluation approaches. We then identify and describe opportunities to: (1) develop new conceptual frameworks and interdisciplinary approaches that draw on ecological state-and-transition models to improve the accuracy and relevance of assessments of anthropogenic dust emissions; (2) improve model fidelity and capacity for change detection to quantify anthropogenic impacts on aeolian processes; and (3) enhance field research and monitoring networks to support dust model applications to evaluate the impacts of disturbance processes on local to global-scale wind erosion and dust emissions.

Morphology, Reproduction and Diet in Australian and Papuan Death Adders (Acanthophis, Elapidae)

OpenAIRE

Shine, Richard; Spencer, Carol L.; Keogh, J. Scott

2014-01-01

Death adders (genus Acanthophis) differ from most other elapid snakes, and resemble many viperid snakes, in their thickset morphology and ambush foraging mode. Although these snakes are widely distributed through Australia and Papua New Guinea, their basic biology remains poorly known. We report morphological and ecological data based upon dissection of >750 museum specimens drawn from most of the range of the genus. Female death adders grow larger than conspecific males, to about the same ex...

Genetic Determinism vs. Phenotypic Plasticity in Protist Morphology.

Science.gov (United States)

Mulot, Matthieu; Marcisz, Katarzyna; Grandgirard, Lara; Lara, Enrique; Kosakyan, Anush; Robroek, Bjorn J M; Lamentowicz, Mariusz; Payne, Richard J; Mitchell, Edward A D

2017-11-01

Untangling the relationships between morphology and phylogeny is key to building a reliable taxonomy, but is especially challenging for protists, where the existence of cryptic or pseudocryptic species makes finding relevant discriminant traits difficult. Here we use Hyalosphenia papilio (a testate amoeba) as a model species to investigate the contribution of phylogeny and phenotypic plasticity in its morphology. We study the response of H. papilio morphology (shape and pores number) to environmental variables in (i) a manipulative experiment with controlled conditions (water level), (ii) an observational study of a within-site natural ecological gradient (water level), and (iii) an observational study across 37 European peatlands (climate). We showed that H. papilio morphology is correlated to environmental conditions (climate and water depth) as well as geography, while no relationship between morphology and phylogeny was brought to light. The relative contribution of genetic inheritance and phenotypic plasticity in shaping morphology varies depending on the taxonomic group and the trait under consideration. Thus, our data call for a reassessment of taxonomy based on morphology alone. This clearly calls for a substantial increase in taxonomic research on these globally still under-studied organisms leading to a reassessment of estimates of global microbial eukaryotic diversity. © 2017 The Author(s) Journal of Eukaryotic Microbiology © 2017 International Society of Protistologists.

Sustainability of utility-scale solar energy – critical ecological concepts

Science.gov (United States)

Moore-O'Leary, Kara A.; Hernandez, Rebecca R.; Johnston, Dave S.; Abella, Scott R.; Tanner, Karen E.; Swanson, Amanda C.; Kreitler, Jason R.; Lovich, Jeffrey E.

2017-01-01

Renewable energy development is an arena where ecological, political, and socioeconomic values collide. Advances in renewable energy will incur steep environmental costs to landscapes in which facilities are constructed and operated. Scientists – including those from academia, industry, and government agencies – have only recently begun to quantify trade-offs in this arena, often using ground-mounted, utility-scale solar energy facilities (USSE, ≥1 megawatt) as a model. Here, we discuss five critical ecological concepts applicable to the development of more sustainable USSE with benefits over fossil-fuel-generated energy: (1) more sustainable USSE development requires careful evaluation of trade-offs between land, energy, and ecology; (2) species responses to habitat modification by USSE vary; (3) cumulative and large-scale ecological impacts are complex and challenging to mitigate; (4) USSE development affects different types of ecosystems and requires customized design and management strategies; and (5) long-term ecological consequences associated with USSE sites must be carefully considered. These critical concepts provide a framework for reducing adverse environmental impacts, informing policy to establish and address conservation priorities, and improving energy production sustainability.

Quantifying predation pressure along an urbanisation gradient in Denmark using artificial caterpillars

DEFF Research Database (Denmark)

Ferrante, Marco; Lo Cacciato, Alessandro; Lövei, Gabor L

2014-01-01

Urbanisation results in a marked modification of habitats and influences several ecological processes, some of which give rise to beneficial ecological services. Natural pest control, the effect of predators on prey is one of such services. We quantified changes in the incidence of predation...... an urbanisation gradient (rural-suburban-urban). Artificial caterpillars were placed on the ground in order to obtain an estimate of the incidence of predation at ground level. Half (50%) of the 1398 caterpillars were "attacked" and 28.8% of the bites were those of chewing insects. We attributed the majority.......3% in suburban and 16.4% in urban forest fragments. Mammals exerted the highest predation pressure in suburban habitats (22.2% vs. 4.9% in forest, and 8.1% in urban forest fragments)....

Overlap and partitioning of the ecological and isotopic niches

Science.gov (United States)

Elizabeth A. Flaherty; Merav Ben-David

2010-01-01

Recently, it was proposed that stable isotope patterns can be used to quantify the width of the ecological niche of animals. However, the potential effects of habitat use on isotopic patterns of consumers have not been fully explored and consequently isotopic patterns may yield deceptive estimates of niche width. Here, we simulated four different scenarios of a...

Integrating the statistical analysis of spatial data in ecology

Science.gov (United States)

A. M. Liebhold; J. Gurevitch

2002-01-01

In many areas of ecology there is an increasing emphasis on spatial relationships. Often ecologists are interested in new ways of analyzing data with the objective of quantifying spatial patterns, and in designing surveys and experiments in light of the recognition that there may be underlying spatial pattern in biotic responses. In doing so, ecologists have adopted a...

Ecological traits influence the phylogenetic structure of bird species co-occurrences worldwide

NARCIS (Netherlands)

Barnagaud, J.-Y.; Kissling, W.D.; Sandel, B.; Eiserhardt, W.L.; Şekercioğlu, Ç.H.; Enquist, B.J.; Tsirogiannis, C.; Svenning, J.-C.

2014-01-01

The extent to which species’ ecological and phylogenetic relatedness shape their co-occurrence patterns at large spatial scales remains poorly understood. By quantifying phylogenetic assemblage structure within geographic ranges of >8000 bird species, we show that global co-occurrence patterns are

Evaluating the morphological completeness of a training image.

Science.gov (United States)

Gao, Mingliang; Teng, Qizhi; He, Xiaohai; Feng, Junxi; Han, Xue

2017-05-01

Understanding the three-dimensional (3D) stochastic structure of a porous medium is helpful for studying its physical properties. A 3D stochastic structure can be reconstructed from a two-dimensional (2D) training image (TI) using mathematical modeling. In order to predict what specific morphology belonging to a TI can be reconstructed at the 3D orthogonal slices by the method of 3D reconstruction, this paper begins by introducing the concept of orthogonal chords. After analyzing the relationship among TI morphology, orthogonal chords, and the 3D morphology of orthogonal slices, a theory for evaluating the morphological completeness of a TI is proposed for the cases of three orthogonal slices and of two orthogonal slices. The proposed theory is evaluated using four TIs of porous media that represent typical but distinct morphological types. The significance of this theoretical evaluation lies in two aspects: It allows special morphologies, for which the attributes of a TI can be reconstructed at a special orthogonal slice of a 3D structure, to be located and quantified, and it can guide the selection of an appropriate reconstruction method for a special TI.

Ecological footprint accounting for energy and resource in China

International Nuclear Information System (INIS)

Chen, B.; Chen, G.Q.; Yang, Z.F.; Jiang, M.M.

2007-01-01

Resource consumption of the Chinese society from 1981 to 2001 is represented by ecological footprint (EF) as an aggregate indicator. The debate, advances and implications of EF are investigated in detail. EF intensity is also provided to depict the resource consumption level corresponding to unit economic output. The results show that the EF per capita always exceeded the biocapacity and the EF intensity increased steadily over the study period. In addition, sectoral analysis for each EF component is also conducted. The appropriation in the global ecological sense of Chinese society with the second largest energy consumption in the world is therefore quantified and evaluated

Disentangling the phylogenetic and ecological components of spider phenotypic variation.

Science.gov (United States)

Gonçalves-Souza, Thiago; Diniz-Filho, José Alexandre Felizola; Romero, Gustavo Quevedo

2014-01-01

An understanding of how the degree of phylogenetic relatedness influences the ecological similarity among species is crucial to inferring the mechanisms governing the assembly of communities. We evaluated the relative importance of spider phylogenetic relationships and ecological niche (plant morphological variables) to the variation in spider body size and shape by comparing spiders at different scales: (i) between bromeliads and dicot plants (i.e., habitat scale) and (ii) among bromeliads with distinct architectural features (i.e., microhabitat scale). We partitioned the interspecific variation in body size and shape into phylogenetic (that express trait values as expected by phylogenetic relationships among species) and ecological components (that express trait values independent of phylogenetic relationships). At the habitat scale, bromeliad spiders were larger and flatter than spiders associated with the surrounding dicots. At this scale, plant morphology sorted out close related spiders. Our results showed that spider flatness is phylogenetically clustered at the habitat scale, whereas it is phylogenetically overdispersed at the microhabitat scale, although phylogenic signal is present in both scales. Taken together, these results suggest that whereas at the habitat scale selective colonization affect spider body size and shape, at fine scales both selective colonization and adaptive evolution determine spider body shape. By partitioning the phylogenetic and ecological components of phenotypic variation, we were able to disentangle the evolutionary history of distinct spider traits and show that plant architecture plays a role in the evolution of spider body size and shape. We also discussed the relevance in considering multiple scales when studying phylogenetic community structure.

Ecological stability of landscape - ecological infrastructure - ecological management

International Nuclear Information System (INIS)

1992-01-01

The Field Workshop 'Ecological Stability of Landscape - Ecological Infrastructure - Ecological Management' was held within a State Environmental Programme financed by the Federal Committee for the Environment. The objectives of the workshop were to present Czech and Slovak approaches to the ecological stability of the landscape by means of examples of some case studies in the field, and to exchange ideas, theoretical knowledge and practical experience on implementing the concept of ecological infrastructure in landscape management. Out of 19 papers contained in the proceedings, 3 items were inputted to the INIS system. (Z.S.)

Quantifying the invasiveness of species

Directory of Open Access Journals (Sweden)

Robert Colautti

2014-04-01

Full Text Available The success of invasive species has been explained by two contrasting but non-exclusive views: (i intrinsic factors make some species inherently good invaders; (ii species become invasive as a result of extrinsic ecological and genetic influences such as release from natural enemies, hybridization or other novel ecological and evolutionary interactions. These viewpoints are rarely distinguished but hinge on distinct mechanisms leading to different management scenarios. To improve tests of these hypotheses of invasion success we introduce a simple mathematical framework to quantify the invasiveness of species along two axes: (i interspecific differences in performance among native and introduced species within a region, and (ii intraspecific differences between populations of a species in its native and introduced ranges. Applying these equations to a sample dataset of occurrences of 1,416 plant species across Europe, Argentina, and South Africa, we found that many species are common in their native range but become rare following introduction; only a few introduced species become more common. Biogeographical factors limiting spread (e.g. biotic resistance, time of invasion therefore appear more common than those promoting invasion (e.g. enemy release. Invasiveness, as measured by occurrence data, is better explained by inter-specific variation in invasion potential than biogeographical changes in performance. We discuss how applying these comparisons to more detailed performance data would improve hypothesis testing in invasion biology and potentially lead to more efficient management strategies.

[Research advances in heavy metals pollution ecology of diatom].

Science.gov (United States)

Ding, Teng-Da; Ni, Wan-Min; Zhang, Jian-Ying

2012-03-01

Diatom, due to its high sensitivity to environmental change, is one of the bio-indicators of aquatic ecosystem health, and some typical diatom species have been applied to indicate the heavy metals pollution of water body. With the focus on the surface water heavy metals pollution, this paper reviewed the research advances in the toxic effect of heavy metals pollution on diatom, biosorption and bioaccumulation of heavy metals by diatom, ecological adaptation mechanisms of diatom to heavy metals pollution, and roles of diatom as bio-indicator and in ecological restoration of heavy metals pollution. The growth tendency of diatom and the morphological change of frustule under heavy metals pollution as well as the differences in heavy metals biosorption and bioaccumulation by diatom, the ecological adaptation mechanisms of diatom on heavy metals surface complexation and ion exchange, and the roles of diatom as bio-indicator and in ecological restoration of heavy metals polluted water body were also discussed. This review could provide scientific evidences for the prevention of aquatic ecosystems heavy metals pollution and related early warning techniques.

How will climate novelty influence ecological forecasts? Using the Quaternary to assess future reliability.

Science.gov (United States)

Fitzpatrick, Matthew C; Blois, Jessica L; Williams, John W; Nieto-Lugilde, Diego; Maguire, Kaitlin C; Lorenz, David J

2018-03-23

Future climates are projected to be highly novel relative to recent climates. Climate novelty challenges models that correlate ecological patterns to climate variables and then use these relationships to forecast ecological responses to future climate change. Here, we quantify the magnitude and ecological significance of future climate novelty by comparing it to novel climates over the past 21,000 years in North America. We then use relationships between model performance and climate novelty derived from the fossil pollen record from eastern North America to estimate the expected decrease in predictive skill of ecological forecasting models as future climate novelty increases. We show that, in the high emissions scenario (RCP 8.5) and by late 21st century, future climate novelty is similar to or higher than peak levels of climate novelty over the last 21,000 years. The accuracy of ecological forecasting models is projected to decline steadily over the coming decades in response to increasing climate novelty, although models that incorporate co-occurrences among species may retain somewhat higher predictive skill. In addition to quantifying future climate novelty in the context of late Quaternary climate change, this work underscores the challenges of making reliable forecasts to an increasingly novel future, while highlighting the need to assess potential avenues for improvement, such as increased reliance on geological analogs for future novel climates and improving existing models by pooling data through time and incorporating assemblage-level information. © 2018 John Wiley & Sons Ltd.

Quantifying the abnormal hemodynamics of sickle cell anemia

Science.gov (United States)

Lei, Huan; Karniadakis, George

2012-02-01

Sickle red blood cells (SS-RBC) exhibit heterogeneous morphologies and abnormal hemodynamics in deoxygenated states. A multi-scale model for SS-RBC is developed based on the Dissipative Particle Dynamics (DPD) method. Different cell morphologies (sickle, granular, elongated shapes) typically observed in deoxygenated states are constructed and quantified by the Asphericity and Elliptical shape factors. The hemodynamics of SS-RBC suspensions is studied in both shear and pipe flow systems. The flow resistance obtained from both systems exhibits a larger value than the healthy blood flow due to the abnormal cell properties. Moreover, SS-RBCs exhibit abnormal adhesive interactions with both the vessel endothelium cells and the leukocytes. The effect of the abnormal adhesive interactions on the hemodynamics of sickle blood is investigated using the current model. It is found that both the SS-RBC - endothelium and the SS-RBC - leukocytes interactions, can potentially trigger the vicious ``sickling and entrapment'' cycles, resulting in vaso-occlusion phenomena widely observed in micro-circulation experiments.

Quantitative assessment of morphology, T{sub 1ρ}, and T{sub 2} of shoulder cartilage using MRI

Energy Technology Data Exchange (ETDEWEB)

Nardo, Lorenzo; Carballido-Gamio, Julio; Tang, Solomon; Lai, Andrew; Krug, Roland [University of California, San Francisco, Musculoskeletal Quantitative Imaging Research Group, Department of Radiology and Biomedical Imaging, San Francisco, CA (United States)

2016-12-15

The aim of this study was to assess the feasibility of quantifying shoulder cartilage morphology and relaxometry in a clinically feasible scan time comparing different pulse sequences and assessing their reproducibility at 3 Tesla. Three pulse sequences were compared for morphological assessments of shoulder cartilage thickness and volume (SPGR, MERGE, FIESTA), while a combined T1ρ-T2 sequence was optimized for relaxometry measurements. The shoulders of six healthy subjects were scanned twice with repositioning, and the cartilage was segmented and quantified. The degree of agreement between the three morphological sequences was assessed using Bland-Altman plots, while the morphological and relaxometry reproducibility were assessed with root-mean-square coefficients of variation (RMS-CVs) Bland-Altman plots indicated good levels of agreement between the morphological assessments of the three sequences. The reproducibility of morphological assessments yielded RMS-CVs between 4.0 and 17.7 %. All sequences correlated highly (R > 0.9) for morphologic assessments with no statistically significant differences. For relaxometry assessments of humeral cartilage, RMS-CVs of 6.4 and 10.6 % were found for T1ρ and T2, respectively. The assessment of both cartilage morphology and relaxometry is feasible in the shoulder with SPGR, humeral head, and T1ρ being the more reproducible morphological sequence, anatomic region, and quantitative sequence, respectively. (orig.)

Examination of High Resolution Channel Topography to Determine Suitable Metrics to Characterize Morphological Complexity

Science.gov (United States)

Stewart, R. L.; Gaeuman, D.

2015-12-01

Complex bed morphology is deemed necessary to restore salmonid habitats, yet quantifiable metrics that capture channel complexity have remained elusive. This work utilizes high resolution topographic data from the 40 miles of the Trinity River of northern California to determine a suitable metric for characterizing morphological complexity at the reach scale. The study area is segregated into reaches defined by individual riffle pool units or aggregates of several consecutive units. Potential measures of complexity include rugosity and depth statistics such as standard deviation and interquartile range, yet previous research has shown these metrics are scale dependent and subject to sampling density-based bias. The effect of sampling density on the present analysis has been reduced by underrepresenting the high resolution topographic data as a 3'x 3' raster so that all areas are equally sampled. Standard rugosity, defined as the three-dimensional surface area divided by projected area, has been shown to be dependent on average depth. We therefore define R*, a empirically depth-corrected rugosity metric in which rugosity is corrected using an empirical relationship based on linear regression between the standard rugosity metric and average depth. By removing the dependence on depth using a regression based on the study reach, R* provides a measure reach scale complexity relative to the entire study area. The interquartile range of depths is also depth-dependent, so we defined a non-dimensional metric (IQR*) as the interquartile range dividing by median depth. These are calculated to develop rankings of channel complexity which, are found to closely agree with perceived channel complexity observed in the field. Current efforts combine these measures of morphological complexity with salmonid habitat suitability to evaluate the effects of channel complexity on the various life stages of salmonids. Future work will investigate the downstream sequencing of channel

Advantages and limitations of quantitative PCR (Q-PCR)-based approaches in microbial ecology.

Science.gov (United States)

Smith, Cindy J; Osborn, A Mark

2009-01-01

Quantitative PCR (Q-PCR or real-time PCR) approaches are now widely applied in microbial ecology to quantify the abundance and expression of taxonomic and functional gene markers within the environment. Q-PCR-based analyses combine 'traditional' end-point detection PCR with fluorescent detection technologies to record the accumulation of amplicons in 'real time' during each cycle of the PCR amplification. By detection of amplicons during the early exponential phase of the PCR, this enables the quantification of gene (or transcript) numbers when these are proportional to the starting template concentration. When Q-PCR is coupled with a preceding reverse transcription reaction, it can be used to quantify gene expression (RT-Q-PCR). This review firstly addresses the theoretical and practical implementation of Q-PCR and RT-Q-PCR protocols in microbial ecology, highlighting key experimental considerations. Secondly, we review the applications of (RT)-Q-PCR analyses in environmental microbiology and evaluate the contribution and advances gained from such approaches. Finally, we conclude by offering future perspectives on the application of (RT)-Q-PCR in furthering understanding in microbial ecology, in particular, when coupled with other molecular approaches and more traditional investigations of environmental systems.

Primate dental ecology: How teeth respond to the environment.

Science.gov (United States)

Cuozzo, Frank P; Ungar, Peter S; Sauther, Michelle L

2012-06-01

Teeth are central for the study of ecology, as teeth are at the direct interface between an organism and its environment. Recent years have witnessed a rapid growth in the use of teeth to understand a broad range of topics in living and fossil primate biology. This in part reflects new techniques for assessing ways in which teeth respond to, and interact with, an organism's environment. Long-term studies of wild primate populations that integrate dental analyses have also provided a new context for understanding primate interactions with their environments. These new techniques and long-term field studies have allowed the development of a new perspective-dental ecology. We define dental ecology as the broad study of how teeth respond to, or interact with, the environment. This includes identifying patterns of dental pathology and tooth use-wear, as they reflect feeding ecology, behavior, and habitat variation, including areas impacted by anthropogenic disturbance, and how dental development can reflect environmental change and/or stress. The dental ecology approach, built on collaboration between dental experts and ecologists, holds the potential to provide an important theoretical and practical framework for inferring ecology and behavior of fossil forms, for assessing environmental change in living populations, and for understanding ways in which habitat impacts primate growth and development. This symposium issue brings together experts on dental morphology, growth and development, tooth wear and health, primate ecology, and paleontology, to explore the broad application of dental ecology to questions of how living and fossil primates interact with their environments. Copyright © 2012 Wiley Periodicals, Inc.

Morphological quantification of hierarchical geomaterials by X-ray nano-CT bridges the gap from nano to micro length scales

KAUST Repository

Brisard, S.; Chae, R. S.; Bihannic, I.; Michot, L.; Guttmann, P.; Thieme, J.; Schneider, G.; Monteiro, P. J. M.; Levitz, P.

2012-01-01

Morphological quantification of the complex structure of hierarchical geomaterials is of great relevance for Earth science and environmental engineering, among others. To date, methods that quantify the 3D morphology on length scales ranging from a

Tendinous framework of anurans reveals an all-purpose morphology.

Science.gov (United States)

Fratani, Jéssica; Ponssa, María Laura; Abdala, Virginia

2018-02-01

Tendons are directly associated with movement, amplifying power and reducing muscular work. Taking into account habitat and locomotor challenges faced by anurans, we identify the more conspicuous superficial tendons of a neotropical anuran group and investigate their relation to the former factors. We show that tendons can be visualized as an anatomical framework connected through muscles and/or fascia, and describe the most superficial tendinous layer of the postcranium of Leptodactylus latinasus. To analyze the relation between tendon morphology and ecological characters, we test the relative length ratio of 10 tendon-muscle (t-m) elements in 45 leptodactylid species while taking phylogeny into account. We identify the evolutionary model that best explains our variables. Additionally, we optimize t-m ratio values, and the shape of the longissimus dorsi insertion onto a selected phylogeny of the species. Our data show the existence of an all-purpose morphology that seems to have evolved independently of ecology and functional requirements. This is indicated by no significant relation between morphometric data of the analyzed tendons and habitat use or locomotion, a strong phylogenetic component to most of the analyzed variables, and a generalized pattern of intermediate values for ancestral states. Ornstein-Uhlenbeck is the model that best explains most t-m variables, indicating that stabilizing selection or selective optima might be driving shifts in tendon length within Leptodactylidae. Herein, we show the substantial influence that phylogeny has on tendon morphology, demonstrating that a generalized and stable morphological configuration of tendons is adequate to enable versatile locomotor modes and habitat use. This is an attempt to present the tendinous system as a framework to body support in vertebrates, and can be considered a starting point for further ecomorphological research of this anatomical system in anurans. Copyright © 2017 Elsevier GmbH. All

The role of habitat shift in the evolution of lizard morphology: evidence from tropical Tropidurus

OpenAIRE

Vitt, Laurie J.; Caldwell, Janalee P.; Zani, Peter A.; Titus, Tom A.

1997-01-01

We compared morphology of two geographically close populations of the tropical lizard Tropidurus hispidus to test the hypothesis that habitat structure influences the evolution of morphology and ecology at the population level. T. hispidus isolated on a rock outcrop surrounded by tropical forest use rock crevices for refuge and appear dorsoventrally compressed compared with those in open savanna. A principal components analysis revealed that the populations were differentially distributed alo...

Bariatric surgery, gut morphology and enteroendocrine cells

DEFF Research Database (Denmark)

Hansen, Carl Frederik

40 hormones. In this PhD study, gut morphology and the population of endocrine cells have been examined in three rodent animal models using stereological techniques. First, in a rodent model of type-2 diabetes (T2DM), the Zucker diabetic fatty rat (ZDF), the population of endocrine L-cells...... to contribute to the positive effects of bariatic surgery but the mechanisms remain largely unknown. The endocrine cells of the gastrointestinal tract that produce and secrete hormones are difficult to examine as they are distributed as single cells. Several types of endocrine cells together produce more than...... and the gut morphology were quantified. The number of Lcells was 4.8 million in the normal rat and the L-cells were found to double in number in the diabetic ZDF rat model. Second, the L-cell population, gut morphology and endocrine cell gene expression were examined in a rodent model of Roux-en-Y gastric...

Morphology, taxonomy and ecology of Thraustochytrids and Labyrinthulids, the marine counterparts of zoosporic fungi

Digital Repository Service at National Institute of Oceanography (India)

RaghuKumar, S.

ecology and the fact that mycologists have traditionally studied these unique organisms, their inclusion in the discipline of mycology is well justified. In this, followed are the arguments put forth by Barr (1992) for including the Chytridiomycota...

The Iberian genus Paraphaenops Jeannel, 1916 (Coleoptera: Carabidae: Trechini): Morphology, phylogeny and geographical distribution

DEFF Research Database (Denmark)

Ortuño, Vicente M.; Sendra, Alberto; P. S. Reboleira, Ana Sofia

2017-01-01

) and one nuclear (LSU) gene fragments evidenced a strong divergence for all markers considered between P. breuilianus and the new species P. fadriquei sp. nov. The strong genetic differences between the two taxa contrast singularly with the extreme morphological homogeneity of the genus. The ecological......The species Paraphaenops breuilianus (Jeannel, 1916) is an Iberian iconic cave beetle with “aphaenopsian” facies, monospecific until now. An extensive field work over the last years allowed the revision of this peculiar genus using the combinations of morphological, molecular and ecological...... approaches and led to the description of new taxa Paraphaenops fadriquei Ortuño and Faille sp. nov., Paraphaenops breuilianus espanoli Ortuño and Faille ssp. nov. and the full larval diagnosis of the third larval instar of the type species. The sequencing of two mitochondrial (cox1, rrnl + tRNA-Leu + nad1...

Sexual dimorphism in bite performance drives morphological variation in chameleons.

Science.gov (United States)

da Silva, Jessica M; Herrel, Anthony; Measey, G John; Tolley, Krystal A

2014-01-01

Phenotypic performance in different environments is central to understanding the evolutionary and ecological processes that drive adaptive divergence and, ultimately, speciation. Because habitat structure can affect an animal's foraging behaviour, anti-predator defences, and communication behaviour, it can influence both natural and sexual selection pressures. These selective pressures, in turn, act upon morphological traits to maximize an animal's performance. For performance traits involved in both social and ecological activities, such as bite force, natural and sexual selection often interact in complex ways, providing an opportunity to understand the adaptive significance of morphological variation with respect to habitat. Dwarf chameleons within the Bradypodion melanocephalum-Bradypodion thamnobates species complex have multiple phenotypic forms, each with a specific head morphology that could reflect its use of either open- or closed-canopy habitats. To determine whether these morphological differences represent adaptations to their habitats, we tested for differences in both absolute and relative bite performance. Only absolute differences were found between forms, with the closed-canopy forms biting harder than their open-canopy counterparts. In contrast, sexual dimorphism was found for both absolute and relative bite force, but the relative differences were limited to the closed-canopy forms. These results indicate that both natural and sexual selection are acting within both habitat types, but to varying degrees. Sexual selection seems to be the predominant force within the closed-canopy habitats, which are more protected from aerial predators, enabling chameleons to invest more in ornamentation for communication. In contrast, natural selection is likely to be the predominant force in the open-canopy habitats, inhibiting the development of conspicuous secondary sexual characteristics and, ultimately, enforcing their overall diminutive body size and

Analysis of airborne LiDAR surveys to quantify the characteristic morphologies of northern forested wetlands

Science.gov (United States)

Murray C. Richardson; Carl P. J. Mitchell; Brian A. Branfireun; Randall K. Kolka

2010-01-01

A new technique for quantifying the geomorphic form of northern forested wetlands from airborne LiDAR surveys is introduced, demonstrating the unprecedented ability to characterize the geomorphic form of northern forested wetlands using high-resolution digital topography. Two quantitative indices are presented, including the lagg width index (LWI) which objectively...

Ecological, morphological and genetic divergence of sympatric North Atlantic killer whale populations

DEFF Research Database (Denmark)

Foote, Andrew D; Newton, Jason; Piertney, Stuart B

2009-01-01

promoting divergence. Here we use morphological traits, nitrogen stable isotope ratios and tooth wear to characterize two disparate types of North Atlantic killer whale. We find a highly specialist type, which reaches up to 8.5 m in length and a generalist type which reaches up to 6.6 m in length...

Ecological divergence and evolutionary transition of resprouting types in Banksia attenuata.

Science.gov (United States)

He, Tianhua

2014-08-01

Resprouting is a key functional trait that allows plants to survive diverse disturbances. The fitness benefits associated with resprouting include a rapid return to adult growth, early flowering, and setting seed. The resprouting responses observed following fire are varied, as are the ecological outcomes. Understanding the ecological divergence and evolutionary pathways of different resprouting types and how the environment and genetics interact to drive such morphological evolution represents an important, but under-studied, topic. In the present study, microsatellite markers and microevolutionary approaches were used to better understand: (1) whether genetic differentiation is related to morphological divergence among resprouting types and if so, whether there are any specific genetic variations associated with morphological divergence and (2) the evolutionary pathway of the transitions between two resprouting types in Banksia attenuata (epicormic resprouting from aerial stems or branch; resprouting from a underground lignotuber). The results revealed an association between population genetic differentiation and the morphological divergence of postfire resprouting types in B. attenuata. A microsatellite allele has been shown to be associated with epicormic populations. Approximate Bayesian Computation analysis revealed a likely evolutionary transition from epicormic to lignotuberous resprouting in B. attenuata. It is concluded that the postfire resprouting type in B. attenuata is likely determined by the fire's characteristics. The differentiated expression of postfire resprouting types in different environments is likely a consequence of local genetic adaptation. The capacity to shift the postfire resprouting type to adapt to diverse fire regimes is most likely the key factor explaining why B. attenuata is the most widespread member of the Banksia genus.

Ecological response of a multi-purpose river development project using macro-invertebrates richness and fish habitat value

International Nuclear Information System (INIS)

Pellaud, M.

2007-05-01

It has been acknowledged that river morphology and hydrology have been intensively altered due to the anthropic demands in floodplain land use and management, flood protection, promotion of navigability or energy production. Rivers were transformed in water highways, having lost contact with their surrounding floodplain as well as the plethora of ecological processes and occupants once thriving in these ecotonal zones. The identification of this emerging threat of morphological and hydrological alteration on ecological integrity adds further complexity in the exploitation of hydrosystem resources. These resources are heavily coveted and guarded by different lobbies each having strategic views on future project development. Stakeholders may want to promote hydro-electricity, ecologists a natural reserve, communes may wish to have an increased flood protection and leisure promoters a nautical center. As a result, the proposition of a river development project is certain to face opposition of one party or the other. The motivations of this dissertation are anchored in this context, where various and sometimes conflicting potentials for hydrosystem exploitation remain. This works aims at contributing scientifically to an innovative approach at the conception phase of a multi-purpose river development project by developing the ecological module to be implemented in the general project's optimizer. The SYNERGIE project hypothesis is that it should be possible to identify a synergetic pattern joining the interests of ecological integrity, flood safety, energy production and leisure development. Such a multi-objective river development project would stand more chance of acceptance. This dissertation focuses on the ecological aspects of such a river development project and an application on the regulated Swiss Upper Rhone River. Is expected an ecological answer to a river development project design / management which has to be compatible with Heller's Heller (2007) general

Integrating a DNA barcoding project with an ecological survey: a case study on temperate intertidal polychaete communities in Qingdao, China

Science.gov (United States)

Zhou, Hong; Zhang, Zhinan; Chen, Haiyan; Sun, Renhua; Wang, Hui; Guo, Lei; Pan, Haijian

2010-07-01

In this study, we integrated a DNA barcoding project with an ecological survey on intertidal polychaete communities and investigated the utility of CO1 gene sequence as a DNA barcode for the classification of the intertidal polychaetes. Using 16S rDNA as a complementary marker and combining morphological and ecological characterization, some of dominant and common polychaete species from Chinese coasts were assessed for their taxonomic status. We obtained 22 haplotype gene sequences of 13 taxa, including 10 CO1 sequences and 12 16S rDNA sequences. Based on intra- and inter-specific distances, we built phylogenetic trees using the neighbor-joining method. Our study suggested that the mitochondrial CO1 gene was a valid DNA barcoding marker for species identification in polychaetes, but other genes, such as 16S rDNA, could be used as a complementary genetic marker. For more accurate species identification and effective testing of species hypothesis, DNA barcoding should be incorporated with morphological, ecological, biogeographical, and phylogenetic information. The application of DNA barcoding and molecular identification in the ecological survey on the intertidal polychaete communities demonstrated the feasibility of integrating DNA taxonomy and ecology.

Three-dimensional geometric morphometric analysis of talar morphology in extant gorilla taxa from highland and lowland habitats.

Science.gov (United States)

Knigge, Ryan P; Tocheri, Matthew W; Orr, Caley M; Mcnulty, Kieran P

2015-01-01

Western gorillas (Gorilla gorilla) are known to climb significantly more often than eastern gorillas (Gorilla beringei), a behavioral distinction attributable to major differences in their respective habitats (i.e., highland vs. lowland). Genetic evidence suggests that the lineages leading to these taxa began diverging from one another between approximately 1 and 3 million years ago. Thus, gorillas offer a special opportunity to examine the degree to which morphology of recently diverged taxa may be "fine-tuned" to differing ecological requirements. Using three-dimensional (3D) geometric morphometrics, we compared talar morphology in a sample of 87 specimens including western (lowland), mountain (highland), and grauer gorillas (lowland and highland populations). Talar shape was captured with a series of landmarks and semilandmarks superimposed by generalized Procrustes analysis. A between-group principal components analysis of overall talar shape separates gorillas by ecological habitat and by taxon. An analysis of only the trochlea and lateral malleolar facet identifies subtle variations in trochlear shape between western lowland and lowland grauer gorillas, potentially indicative of convergent evolution of arboreal adaptations in the talus. Lastly, talar shape scales differently with centroid size for highland and lowland gorillas, suggesting that ankle morphology may track body-size mediated variation in arboreal behaviors differently depending on ecological setting. Several of the observed shape differences are linked biomechanically to the facilitation of climbing in lowland gorillas and to stability and load-bearing on terrestrial substrates in the highland taxa, providing an important comparative model for studying morphological variation in groups known only from fossils (e.g., early hominins). © 2014 Wiley Periodicals, Inc.

Depth-related trends in morphological and functional diversity of demersal fish assemblages in the western Mediterranean Sea

Science.gov (United States)

Farré, Marc; Tuset, Víctor M.; Cartes, Joan E.; Massutí, Enric; Lombarte, Antoni

2016-09-01

The morphological and functional traits of fishes are key factors defining the ecological and biological habits of species within ecosystems. However, little is known about how the depth gradient affects these factors. In the present study, several demersal fish assemblages from the Balearic Islands (western Mediterranean Sea) along a wide depth range (40-2200 m) were morphologically, functionally and ecologically described. The morphological characterization of communities was performed using geometric morphometric methods, while the functional structures were obtained by the functional categorization of species and the application of principal coordinates analysis (PCoA). The results revealed that morphospaces presented less richness of body forms as depth increases, although they showed a progressive spreading of species toward the periphery, with a proliferation of more extreme body traits, demonstrating lower morphological redundancy. In addition, a trend toward the elongation of body shape was also observed with depth. Moreover, functional diversity increased with bathymetry up to 1400 m, where it sharply decreased downwards. This decrease was parallel to a progressive fall of H‧ (ecological diversity) up to 2200 m. Functional redundancy progressively decreased until the deepest assemblage (more constantly in the deeper levels), which was almost exclusively dominated by benthopelagic wandering species feeding on suprabenthos. Redundancy analysis (RDA) demonstrated that both morphological and functional spaces showed high variation along the bathymetric range. Mantel test indicated that the majority of species presented similar spatial distribution within the morphospace and functional space, although in the functional space the more abundant species were always located at the periphery. These results demonstrate that the assessment of the morpho-functional variation between marine communities helps to understand the processes that affect the structure and

Morphogenesis in bat wings: linking development, evolution and ecology.

Science.gov (United States)

Adams, Rick A

2008-01-01

The evolution of powered flight in mammals required specific developmental shifts from an ancestral limb morphology to one adapted for flight. Through studies of comparative morphogenesis, investigators have quantified points and rates of divergence providing important insights into how wings evolved in mammals. Herein I compare growth,development and skeletogenesis of forelimbs between bats and the more ancestral state provided by the rat (Rattus norvegicus)and quantify growth trajectories that illustrate morphological divergence both developmentally and evolutionarily. In addition, I discuss how wing shape is controlled during morphogenesis by applying multivariate analyses of wing bones and wing membranes and discuss how flight dynamics are stabilized during flight ontogeny. Further, I discuss the development of flight in bats in relation to the ontogenetic niche and how juveniles effect populational foraging patterns. In addition, I provide a hypothetical ontogenetic landscape model that predicts how and when selection is most intense during juvenile morphogenesis and test this model with data from a population of the little brown bat, Myotis lucifugus. (c) 2007 S. Karger AG, Basel

Middle ear cavity morphology is consistent with an aquatic origin for testudines

DEFF Research Database (Denmark)

Willis, Katie L; Christensen-Dalsgaard, Jakob; Ketten, Darlene R

2013-01-01

The position of testudines in vertebrate phylogeny is being re-evaluated. At present, testudine morphological and molecular data conflict when reconstructing phylogenetic relationships. Complicating matters, the ecological niche of stem testudines is ambiguous. To understand how turtles have...... evolved to hear in different environments, we examined middle ear morphology and scaling in most extant families, as well as some extinct species, using 3-dimensional reconstructions from micro magnetic resonance (MR) and submillimeter computed tomography (CT) scans. All families of testudines exhibited...... volume resonating in an underwater sound field, the calculated resonances for the volumes of the middle ear cavities largely fell within testudine hearing ranges. Although there were some differences in morphology, there were no statistically significant differences in the scaling of the volume...

Phylogeographic concordance factors quantify phylogeographic congruence among co-distributed species in the Sarracenia alata pitcher plant system.

Science.gov (United States)

Satler, Jordan D; Carstens, Bryan C

2016-05-01

Comparative phylogeographic investigations have identified congruent phylogeographic breaks in co-distributed species in nearly every region of the world. The qualitative assessments of phylogeographic patterns traditionally used to identify such breaks, however, are limited because they rely on identifying monophyletic groups across species and do not account for coalescent stochasticity. Only long-standing phylogeographic breaks are likely to be obvious; many species could have had a concerted response to more recent landscape events, yet possess subtle signs of phylogeographic congruence because ancestral polymorphism has not completely sorted. Here, we introduce Phylogeographic Concordance Factors (PCFs), a novel method for quantifying phylogeographic congruence across species. We apply this method to the Sarracenia alata pitcher plant system, a carnivorous plant with a diverse array of commensal organisms. We explore whether a group of ecologically associated arthropods have co-diversified with the host pitcher plant, and identify if there is a positive correlation between ecological interaction and PCFs. Results demonstrate that multiple arthropods share congruent phylogeographic breaks with S. alata, and provide evidence that the level of ecological association can be used to predict the degree of similarity in the phylogeographic pattern. This study outlines an approach for quantifying phylogeographic congruence, a central concept in biogeographic research. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

Inter-hemispheric comparison of CO2 signals in leaf cuticle morphology

NARCIS (Netherlands)

Hincke, A.J.C.

2016-01-01

Despite on-going efforts to understand the effects of the complex CO2-vegetation relationship on plant morphology, a clear picture has not yet been established. In order to better understand and quantify past CO2 dynamics as they relate to hydrological processes and ecosystem interactions, intensive

Ecological community traits and traditional knowledge shape palm ecosystem services in northwestern South America

DEFF Research Database (Denmark)

Cámara-Leret, Rodrigo; Paniagua-Zambrana, Narel; Balslev, Henrik

2014-01-01

Tropical rainforest ecosystems support the maximum expression of biocultural diversity on Earth and preserving them requires understanding and working with the needs of their inhabitants. Here, we com- bine traditional knowledge with ecological data to quantify cross-scale variation in the ecosys...

Fractal Dimension Analysis of MDCT Images for Quantifying the Morphological Changes of the Pulmonary Artery Tree in Patients with Pulmonary Hypertension

Energy Technology Data Exchange (ETDEWEB)

Sun, Haitao; Li, Ning; Guo, Lijun; Gao, Fei; Liu, Cheng [Shandong University, Shandong Medical Imaging Research Institute, Shandong (Korea, Republic of)

2011-06-15

The aim of this study was to use fractal dimension (FD) analysis on multidetector CT (MDCT) images for quantifying the morphological changes of the pulmonary artery tree in patients with pulmonary hypertension (PH). Fourteen patients with PH and 17 patients without PH as controls were studied. All of the patients underwent contrast-enhanced helical CT and transthoracic echocardiography. The pulmonary artery trees were generated using post-processing software, and the FD and projected image area of the pulmonary artery trees were determined with Image J software in a personal computer. The FD, the projected image area and the pulmonary artery pressure (PAP) were statistically evaluated in the two groups. The FD, the projected image area and the PAP of the patients with PH were higher than those values of the patients without PH (p < 0.05, t-test). There was a high correlation of FD with the PAP (r = 0.82, p < 0.05, partial correlation analysis). There was a moderate correlation of FD with the projected image area (r = 0.49, p < 0.05, partial correlation analysis). There was a correlation of the PAP with the projected image area (r = 0.65, p < 0.05, Pearson correlation analysis). The FD of the pulmonary arteries in the PH patients was significantly higher than that of the controls. There is a high correlation of FD with the PAP.

Fractal Dimension Analysis of MDCT Images for Quantifying the Morphological Changes of the Pulmonary Artery Tree in Patients with Pulmonary Hypertension

International Nuclear Information System (INIS)

Sun, Haitao; Li, Ning; Guo, Lijun; Gao, Fei; Liu, Cheng

2011-01-01

The aim of this study was to use fractal dimension (FD) analysis on multidetector CT (MDCT) images for quantifying the morphological changes of the pulmonary artery tree in patients with pulmonary hypertension (PH). Fourteen patients with PH and 17 patients without PH as controls were studied. All of the patients underwent contrast-enhanced helical CT and transthoracic echocardiography. The pulmonary artery trees were generated using post-processing software, and the FD and projected image area of the pulmonary artery trees were determined with Image J software in a personal computer. The FD, the projected image area and the pulmonary artery pressure (PAP) were statistically evaluated in the two groups. The FD, the projected image area and the PAP of the patients with PH were higher than those values of the patients without PH (p < 0.05, t-test). There was a high correlation of FD with the PAP (r = 0.82, p < 0.05, partial correlation analysis). There was a moderate correlation of FD with the projected image area (r = 0.49, p < 0.05, partial correlation analysis). There was a correlation of the PAP with the projected image area (r = 0.65, p < 0.05, Pearson correlation analysis). The FD of the pulmonary arteries in the PH patients was significantly higher than that of the controls. There is a high correlation of FD with the PAP.

The Impact of Organismal Innovation on Functional and Ecological Diversification.

Science.gov (United States)

Wainwright, Peter C; Price, Samantha A

2016-09-01

Innovations in organismal functional morphology are thought to be a major force in shaping evolutionary patterns, with the potential to drive adaptive radiation and influence the evolutionary prospects for lineages. But the evolutionary consequences of innovation are diverse and usually do not result in adaptive radiation. What factors shape the macroevolutionary impact of innovations? We assert that little is known in general about the macroevolutionary outcomes associated with functional innovations and we discuss a framework for studying biological innovations in an evolutionary context. Innovations are novel functional mechanisms that enhance organismal performance. The ubiquity of trade-offs in functional systems means that enhanced performance on one axis often occurs at the expense of performance on another axis, such that many innovations result in an exchange of performance capabilities, rather than an expansion. Innovations may open up new resources for exploitation but their consequences for functional and ecological diversification depend heavily on the adaptive landscape around these novel resources. As an example of a broader program that we imagine, we survey five feeding innovations in labrid fishes, an exceptionally successful and ecologically diverse group of reef fishes, and explore their impact on the rate of evolution of jaw functional morphology. All of the innovations provide performance enhancements and result in changes in patterns of resource use, but most are not associated with subsequent functional diversification or substantial ecological diversification. Because selection acts on a specific performance enhancement and not on the evolutionary potential of an innovation, the enhancement of diversity may be highly serendipitous. The macroevolutionary potential of innovations depends critically on the interaction between the performance enhancement and the ecological opportunity that is exposed. © The Author 2016. Published by Oxford

Delineating ecological boundaries of Hanuman langur species complex in peninsular India using MaxEnt modeling approach.

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Nag, Chetan; Chetan, Nag; Karanth, K Praveen; Praveen, Karanth K; Gururaja, Kotambylu Vasudeva; Vasudeva, Gururaja Kotambylu

2014-01-01

Hanuman langur is one of the widely distributed and extensively studied non-human diurnal primates in India. Until recently it was believed to be a single species - Semnopithecus entellus. Recent molecular and morphological studies suggest that the Hanuman langurs consists of at least three species S. entellus, S. hypoleucos and S. priam. Furthermore, morphological studies suggested that both S. hypoleucos and S. priam have at least three subspecies in each. We explored the use of ecological niche modeling (ENM) to confirm the validity of these seven taxa and an additional taxon S. johnii belonging to the same genus. MaxEnt modeling tool was used with 19 bioclimatic, 12 vegetation and 6 hydrological environmental layers. We reduced total environmental variables to 14 layers after testing for collinearity and an independent test for model prediction was done using ENMTools. A total of 196 non-overlapping data points from primary and secondary sources were used as inputs for ENM. Results showed eight distinct ecological boundaries, corroborating the eight taxa mentioned above thereby confirming validity of these eight taxa. The study, for the first time provided ecological variables that determined the ecological requirements and distribution of members of the Hanuman langur species complex in the Indian peninsula.

Effects of shell morphology on mechanics of zebra and quagga mussel locomotion.

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Peyer, Suzanne M; Hermanson, John C; Lee, Carol Eunmi

2011-07-01

Although zebra mussels (Dreissena polymorpha) initially colonized shallow habitats within the North American Great Lakes, quagga mussels (Dreissena bugensis) are becoming dominant in both shallow- and deep-water habitats. Shell morphology differs among zebra, shallow quagga and deep quagga mussels but functional consequences of such differences are unknown. We examined effects of shell morphology on locomotion for the three morphotypes on hard (typical of shallow habitats) and soft (characteristic of deep habitats) sedimentary substrates. We quantified morphology using the polar moment of inertia, a parameter used in calculating kinetic energy that describes shell area distribution and resistance to rotation. We quantified mussel locomotion by determining the ratio of rotational (K(rot)) to translational kinetic energy (K(trans)). On hard substrate, K(rot):K(trans) of deep quagga mussels was fourfold greater than for the other morphotypes, indicating greater energy expenditure in rotation relative to translation. On soft substrate, K(rot):K(trans) of deep quagga mussels was approximately one-third of that on hard substrate, indicating lower energy expenditure in rotation on soft substrate. Overall, our study demonstrates that shell morphology correlates with differences in locomotion (i.e. K(rot):K(trans)) among morphotypes. Although deep quagga mussels were similar to zebra and shallow quagga mussels in terms of energy expenditure on sedimentary substrate, their morphology was energetically maladaptive for linear movement on hard substrate. As quagga mussels can possess two distinct morphotypes (i.e. shallow and deep morphs), they might more effectively utilize a broader range of substrates than zebra mussels, potentially enhancing their ability to colonize a wider range of habitats.

Sexual Dimorphism in Bite Performance Drives Morphological Variation in Chameleons

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da Silva, Jessica M.; Herrel, Anthony; Measey, G. John; Tolley, Krystal A.

2014-01-01

Phenotypic performance in different environments is central to understanding the evolutionary and ecological processes that drive adaptive divergence and, ultimately, speciation. Because habitat structure can affect an animal’s foraging behaviour, anti-predator defences, and communication behaviour, it can influence both natural and sexual selection pressures. These selective pressures, in turn, act upon morphological traits to maximize an animal’s performance. For performance traits involved in both social and ecological activities, such as bite force, natural and sexual selection often interact in complex ways, providing an opportunity to understand the adaptive significance of morphological variation with respect to habitat. Dwarf chameleons within the Bradypodion melanocephalum-Bradypodion thamnobates species complex have multiple phenotypic forms, each with a specific head morphology that could reflect its use of either open- or closed-canopy habitats. To determine whether these morphological differences represent adaptations to their habitats, we tested for differences in both absolute and relative bite performance. Only absolute differences were found between forms, with the closed-canopy forms biting harder than their open-canopy counterparts. In contrast, sexual dimorphism was found for both absolute and relative bite force, but the relative differences were limited to the closed-canopy forms. These results indicate that both natural and sexual selection are acting within both habitat types, but to varying degrees. Sexual selection seems to be the predominant force within the closed-canopy habitats, which are more protected from aerial predators, enabling chameleons to invest more in ornamentation for communication. In contrast, natural selection is likely to be the predominant force in the open-canopy habitats, inhibiting the development of conspicuous secondary sexual characteristics and, ultimately, enforcing their overall diminutive body size and

Sexual dimorphism in bite performance drives morphological variation in chameleons.

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Jessica M da Silva

Full Text Available Phenotypic performance in different environments is central to understanding the evolutionary and ecological processes that drive adaptive divergence and, ultimately, speciation. Because habitat structure can affect an animal's foraging behaviour, anti-predator defences, and communication behaviour, it can influence both natural and sexual selection pressures. These selective pressures, in turn, act upon morphological traits to maximize an animal's performance. For performance traits involved in both social and ecological activities, such as bite force, natural and sexual selection often interact in complex ways, providing an opportunity to understand the adaptive significance of morphological variation with respect to habitat. Dwarf chameleons within the Bradypodion melanocephalum-Bradypodion thamnobates species complex have multiple phenotypic forms, each with a specific head morphology that could reflect its use of either open- or closed-canopy habitats. To determine whether these morphological differences represent adaptations to their habitats, we tested for differences in both absolute and relative bite performance. Only absolute differences were found between forms, with the closed-canopy forms biting harder than their open-canopy counterparts. In contrast, sexual dimorphism was found for both absolute and relative bite force, but the relative differences were limited to the closed-canopy forms. These results indicate that both natural and sexual selection are acting within both habitat types, but to varying degrees. Sexual selection seems to be the predominant force within the closed-canopy habitats, which are more protected from aerial predators, enabling chameleons to invest more in ornamentation for communication. In contrast, natural selection is likely to be the predominant force in the open-canopy habitats, inhibiting the development of conspicuous secondary sexual characteristics and, ultimately, enforcing their overall diminutive

MORPHOLOGICAL ANALYSIS OF THE LEAVES OF Anacardium occidentale L.

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Glenda Quaresma Ramos

2016-03-01

Full Text Available In morphological studies are analyzed various parameters, ranging from macro scale through the micro scale to the nanometer scale, which contribute to the study of taxonomy, pharmacognosy, ecology, among others. Among the structures found in plants, the leaves are most organs analyzed. This study aimed to analyze morphological features of the leaves of the cashew tree, which is a plant of great commercial importance in Brazil. In this work we observed sinuous epidermal cells in the adaxial and abaxial, characterize their stomata in paracytic surrounded subsidiaries cells. On the abaxial surface the presence of glandular trichomes was observed; and cross-sectional analysis showed a single-layered epidermis with compact mesophyll and several layers of parenchyma cells. Keywords: leaf anatomy; cashew tree; optical microscopy.

Functional morphology of the bovid astragalus in relation to habitat: controlling phylogenetic signal in ecomorphology.

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Barr, W Andrew

2014-11-01

Bovid astragali are one of the most commonly preserved bones in the fossil record. Accordingly, astragali are an important target for studies seeking to predict the habitat preferences of fossil bovids based on bony anatomy. However, previous work has not tested functional hypotheses linking astragalar morphology with habitat while controlling for body size and phylogenetic signal. This article presents a functional framework relating the morphology of the bovid astragalus to habitat-specific locomotor ecology and tests four hypotheses emanating from this framework. Highly cursorial bovids living in structurally open habitats are hypothesized to differ from their less cursorial closed-habitat dwelling relatives in having (1) relatively short astragali to maintain rotational speed throughout the camming motion of the rotating astragalus, (2) a greater range of angular excursion at the hock, (3) relatively larger joint surface areas, and (4) a more pronounced "spline-and-groove" morphology promoting lateral joint stability. A diverse sample of 181 astragali from 50 extant species was scanned using a Next Engine laser scanner. Species were assigned to one of four habitat categories based on the published ecological literature. A series of 11 linear measurements and three joint surface areas were measured on each astragalus. A geometric mean body size proxy was used to size-correct the measurement data. Phylogenetic generalized least squares (PGLS) was used to test for differences between habitat categories while controlling for body size differences and phylogenetic signal. Statistically significant PGLS results support Hypotheses 1 and 2 (which are not mutually exclusive) as well as Hypothesis 3. No support was found for Hypothesis 4. These findings confirm that the morphology of the bovid astragalus is related to habitat-specific locomotor ecology, and that this relationship is statistically significant after controlling for body size and phylogeny. Thus, this study

Quantifying biopsychosocial aspects in everyday contexts: an integrative methodological approach from the behavioral sciences

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Portell, Mariona; Anguera, M Teresa; Hernández-Mendo, Antonio; Jonsson, Gudberg K

2015-01-01

Contextual factors are crucial for evaluative research in psychology, as they provide insights into what works, for whom, in what circumstances, in what respects, and why. Studying behavior in context, however, poses numerous methodological challenges. Although a comprehensive framework for classifying methods seeking to quantify biopsychosocial aspects in everyday contexts was recently proposed, this framework does not contemplate contributions from observational methodology. The aim of this paper is to justify and propose a more general framework that includes observational methodology approaches. Our analysis is rooted in two general concepts: ecological validity and methodological complementarity. We performed a narrative review of the literature on research methods and techniques for studying daily life and describe their shared properties and requirements (collection of data in real time, on repeated occasions, and in natural settings) and classification criteria (eg, variables of interest and level of participant involvement in the data collection process). We provide several examples that illustrate why, despite their higher costs, studies of behavior and experience in everyday contexts offer insights that complement findings provided by other methodological approaches. We urge that observational methodology be included in classifications of research methods and techniques for studying everyday behavior and advocate a renewed commitment to prioritizing ecological validity in behavioral research seeking to quantify biopsychosocial aspects. PMID:26089708

Functional Morphology of Eunicidan (Polychaeta) Jaws

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Clemo, W. C.; Dorgan, K. M.

2016-02-01

Polychaetes exhibit diverse feeding strategies and diets, with some species possessing hardened teeth or jaws of varying complexity. Species in the order Eunicida have complex, rigidly articulated jaws consisting of multiple pairs of maxillae and a pair of mandibles. While all Eunicida possess this general jaw structure, a number of characteristics of the jaw parts vary considerably among families. These differences, described for fossilized and extant species' jaws, were used to infer evolutionary relationships, but current phylogeny shows that jaw structures that are similar among several families are convergent. Little has been done, however, to relate jaw functional morphology and feeding behavior to diet. To explore these relationships, we compared the jaw kinematics of two taxa with similar but evolutionarily convergent jaw structures: Diopatra (Onuphidae) and Lumbrineris (Lumbrineridae). Diopatra species are tube-dwelling and predominantly herbivorous, whereas Lumbrineris species are burrowing carnivores. Jaw kinematics were observed and analyzed by filming individuals biting or feeding and tracking tooth movements in videos. Differences in jaw structure and kinematics between Diopatra and Lumbrineris can be interpreted to be consistent with their differences in diet. Relating jaw morphology to diet would provide insight into early annelid communities by linking fossil teeth (scolecodonts) to the ecological roles of extant species with similar morphologies.

Quantifying resilience

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Allen, Craig R.; Angeler, David G.

2016-01-01

The biosphere is under unprecedented pressure, reflected in rapid changes in our global ecological, social, technological and economic systems. In many cases, ecological and social systems can adapt to these changes over time, but when a critical threshold is surpassed, a system under stress can undergo catastrophic change and reorganize into a different state. The concept of resilience, introduced more than 40 years ago in the ecological sciences, captures the behaviour of systems that can occur in alternative states. The original definition of resilience forwarded by Holling (1973) is still the most useful. It defines resilience as the amount of disturbance that a system can withstand before it shifts into an alternative stable state. The idea of alternative stable states has clear and profound implications for ecological management. Coral reefs, for example, are high-diversity systems that provide key ecosystem services such as fisheries and coastal protection. Human impacts are causing significant, ongoing reef degradation, and many reefs have shifted from coral- to algal-dominated states in response to anthropogenic pressures such as elevated water temperatures and overfishing. Understanding and differentiating between the factors that help maintain reefs in coral-dominated states vs. those that facilitate a shift to an undesired algal-dominated state is a critical step towards sound management and conservation of these, and other, important social–ecological systems.

A method for quantifying and comparing the costs and benefits of alternative riparian zone buffer widths

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Chris B. LeDoux; Ethel Wilkerson

2008-01-01

We developed a method that can be used to quantify the opportunity costs and ecological benefits of implementing alternative streamside management zones/buffer zone widths. The opportunity costs are computed based on the net value of the timber left behind in the buffer zone, the stump-to-mill logging costs for the logging technology that would have been used to...

Surface Morphology Diagram for Cylinder-Forming Block Copolymer Thin Films

International Nuclear Information System (INIS)

Zhang, Xiaohua; Berry, Brian C.; Yager, Kevin G.; Kim, Sangcheol; Jones, Ronald L.; Satija, Sushil; Pickel, Deanna L.; Douglas, Jack F.; Karim, Alamgir

2008-01-01

We investigate the effect of annealing temperature (T), film thickness (hf) on the surface morphology of flow coated films of a cylinder forming block copolymer, poly (styrene-block-methyl methacrylate) (PS-b-PMMA). Surface morphology transitions from a perpendicular to a parallel cylinder orientation with respect to the substrate with increasing hf are observed in these model 'frustrated-interaction' films where the substrate interaction is preferential for one of the blocks (PMMA) and nearly neutral for the other interface (polymer-air). In these films a transition occurs from cylinders oriented parallel to the substrate to a mixed or 'hybrid' state where the two orientations coexist followed by a transition to cylinders oriented perpendicularly to the polymer-air interface for larger hf. The characteristic values of hf defining these surface morphological transitions depend on T and we construct a surface morphology diagram as a function of hf and T. The surface morphology diagram is found to depend on the method of film formation (flow coated versus spun cast films) so non-equilibrium effects evidently have a large effect on the surface pattern morphology. In particular, the residual solvent within the film (quantified by neutron reflectivity measurements) in the context of physics of glass-formation can have a large effect on the surface morphology diagram

Diversity Of Mandibular Morphology In Some Carnivorans

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Rahmat S. J.

2015-06-01

Full Text Available Comparison of mandibular morphology of some aquatic (seals, walruses, and sea otters and terrestrial (hyenas and pandas carnivorans demonstrates a rather general pattern correlating size of condyloid angle, size of gape, and diet. Structural differences of carnivoran jaws reveal morphological and ecological adaptations that are directly correlated with availability of prey, diving depth, feeding competition and specialized feeding methods. Specifically, the inclination of the condyloid process relative to the axis of the alveolar row (= condyloid angle can be used to determine dietary preferences, including size of prey. Generally, carnivorans with a large condyloid angle feed on larger prey, while a low condyloid angle suggests feeding on small prey or can be an advantageous feeding mechanism. Mirounga angustirostris (Northern elephant seal displays sex-specific characters in cranial and postcranial elements. Likewise, significant sexually dimorphic differences in the size of condyloid angle imply that deeper-diving male Northern elephant seals have a feeding niche dissimilar to that of females. Morphological assessment of male M. angustirostris suggests they are bottom-feeding seals that utilize a suction-feeding mechanism to capture small prey and crush shells with their teeth, which become weaker as they age.

Multiscale influence of woody riparian vegetation on fluvial topography quantified with ground-based and airborne lidar

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Bywater-Reyes, Sharon; Wilcox, Andrew C.; Diehl, Rebecca M.

2017-06-01

Coupling between riparian vegetation and river processes can result in the coevolution of plant communities and channel morphology. Quantifying biotic-abiotic interactions remains difficult because of the challenges in making and analyzing appropriately scaled observations. We measure the influence of woody vegetation on channel topography at the patch and reach scales in a sand bed, dryland river system (Santa Maria River, Arizona) with native Populus and invasive Tamarix. At the patch scale, we use ground-based lidar to relate plant morphology to "tail bars" formed in the lee of vegetation. We find vegetation roughness density (λf) to most influence tail-bar shape and size, suggesting coherent flow structures associated with roughness density are responsible for sediment deposition at this scale. Using airborne lidar, we test whether relationships between topography and vegetation morphology observed at the patch scale are persistent at the reach scale. We find that elevation of the channel (relative to the local mean) covaries with a metric of vegetation density, indicating analogous influences of vegetation density on topography across spatial scales. While these results are expected, our approach provides insight regarding interactions between woody riparian vegetation and channel topography at multiple scales, and a means to quantify such interactions for use in other field settings.

Missing ecology: integrating ecological perspectives with the social-ecological system framework

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Graham Epstein

2013-08-01

Full Text Available The social-ecological systems framework was designed to provide a common research tool for interdisciplinary investigations of social-ecological systems. However, its origin in institutional studies of the commons belies its interdisciplinary ambitions and highlights its relatively limited attention to ecology and natural scientific knowledge. This paper considers the biophysical components of the framework and its epistemological foundations as it relates to the incorporation of knowledge from the natural sciences. It finds that the mixture of inductive and deductive reasoning associated with socially-oriented investigations of these systems is lacking on the ecological side, which relies upon induction alone. As a result the paper proposes the addition of a seventh core sub-system to the social-ecological systems framework, ecological rules, which would allow scholars to explicitly incorporate knowledge from the natural sciences for deductive reasoning. The paper shows, through an instructive case study, how the addition of ecological rules can provide a more nuanced description of the factors that contribute to outcomes in social-ecological systems.

Nutritional ecology of insect-plant interactions: persistent handicaps and the need for innovative approaches

NARCIS (Netherlands)

Loon, van J.J.A.; Casas, J.; Pincebourde, S.

2005-01-01

Quantifying the flow of matter and energy in food webs is indispensable when assessing the effects of increases in atmospheric carbon dioxide, ozone level and temperature as a result of global climate change. In insect nutritional ecology, quantification of digestive and metabolic efficiency is

Measures of precision for dissimilarity-based multivariate analysis of ecological communities.

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Anderson, Marti J; Santana-Garcon, Julia

2015-01-01

Ecological studies require key decisions regarding the appropriate size and number of sampling units. No methods currently exist to measure precision for multivariate assemblage data when dissimilarity-based analyses are intended to follow. Here, we propose a pseudo multivariate dissimilarity-based standard error (MultSE) as a useful quantity for assessing sample-size adequacy in studies of ecological communities. Based on sums of squared dissimilarities, MultSE measures variability in the position of the centroid in the space of a chosen dissimilarity measure under repeated sampling for a given sample size. We describe a novel double resampling method to quantify uncertainty in MultSE values with increasing sample size. For more complex designs, values of MultSE can be calculated from the pseudo residual mean square of a permanova model, with the double resampling done within appropriate cells in the design. R code functions for implementing these techniques, along with ecological examples, are provided. © 2014 The Authors. Ecology Letters published by John Wiley & Sons Ltd and CNRS.

Morphological and ecological parallels between sublittoral and abyssal foraminiferal species in the NE Atlantic: a comparison of Stainforthia fusiformis and Stainforthia sp.

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Gooday, Andrew J.; Alve, Elisabeth

Dead specimens of a minute fusiform rotaliid foraminifer are common in the 28-63 μm fraction of multiple corer samples from a 4850 m-deep site on the Porcupine Abyssal Plain (PAP). Their test morphology is remarkably similar to small specimens of Stainforthia fusiformis ( Williamson, 1858), a species which is well known from coastal settings (intertidal to outer shelf) around NW Europe and North America. A detailed comparison of the PAP form with typical individuals of S. fusiformis from Norwegian waters (55-203 m depth), however, reveals slight but consistent morphological differences. The PAP specimens are smaller (test length 40-140 μm) than those from Norway (test length 80-380 μm), the chambers tend to be rather less elongate, the density of pores in the test wall is much lower, and there are differences in apertural features. We therefore conclude that the diminutive abyssal form is a distinct species, here referred to as Stainforthia sp. This interpretation is consistent with increasing evidence for genetic differentiation in deep-sea organisms, particularly along bathymetric gradients. Stainforthia sp. was previously illustrated by Pawlowski as Fursenkoina sp. and appears to be widespread and abundant in the abyssal North Atlantic (>4000 m depth). Stainforthia fusiformis, on the other hand, is most abundant in continental shelf and coastal settings. It extends onto the continental slope in the North Atlantic but has not been reported reliably from depths greater than about 2500 m. We suggest that the striking morphological convergence between these two species reflects the adoption of similar ecological strategies in widely separated habitats. Both are enrichment opportunists, a life-style which may explain the rather broad bathymetric range of Stainforthia fusiformis. This is a dominant species in organically-enriched and sometimes extremely oxygen-depleted environments on the continental shelf, and is a rapid coloniser of formerly azoic habitats. Live

Host Diet Affects the Morphology of Monarch Butterfly Parasites.

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Hoang, Kevin; Tao, Leiling; Hunter, Mark D; de Roode, Jacobus C

2017-06-01

Understanding host-parasite interactions is essential for ecological research, wildlife conservation, and health management. While most studies focus on numerical traits of parasite groups, such as changes in parasite load, less focus is placed on the traits of individual parasites such as parasite size and shape (parasite morphology). Parasite morphology has significant effects on parasite fitness such as initial colonization of hosts, avoidance of host immune defenses, and the availability of resources for parasite replication. As such, understanding factors that affect parasite morphology is important in predicting the consequences of host-parasite interactions. Here, we studied how host diet affected the spore morphology of a protozoan parasite ( Ophryocystis elektroscirrha ), a specialist parasite of the monarch butterfly ( Danaus plexippus ). We found that different host plant species (milkweeds; Asclepias spp.) significantly affected parasite spore size. Previous studies have found that cardenolides, secondary chemicals in host plants of monarchs, can reduce parasite loads and increase the lifespan of infected butterflies. Adding to this benefit of high cardenolide milkweeds, we found that infected monarchs reared on milkweeds of higher cardenolide concentrations yielded smaller parasites, a potentially hidden characteristic of cardenolides that may have important implications for monarch-parasite interactions.

Rapid sympatric ecological differentiation of crater lake cichlid fishes within historic times

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Harrod Chris

2010-05-01

Full Text Available Abstract Background After a volcano erupts, a lake may form in the cooled crater and become an isolated aquatic ecosystem. This makes fishes in crater lakes informative for understanding sympatric evolution and ecological diversification in barren environments. From a geological and limnological perspective, such research offers insight about the process of crater lake ecosystem establishment and speciation. In the present study we use genetic and coalescence approaches to infer the colonization history of Midas cichlid fishes (Amphilophus cf. citrinellus that inhabit a very young crater lake in Nicaragua-the ca. 1800 year-old Lake Apoyeque. This lake holds two sympatric, endemic morphs of Midas cichlid: one with large, hypertrophied lips (~20% of the total population and another with thin lips. Here we test the associated ecological, morphological and genetic diversification of these two morphs and their potential to represent incipient speciation. Results Gene coalescence analyses [11 microsatellite loci and mitochondrial DNA (mtDNA sequences] suggest that crater lake Apoyeque was colonized in a single event from the large neighbouring great lake Managua only about 100 years ago. This founding in historic times is also reflected in the extremely low nuclear and mitochondrial genetic diversity in Apoyeque. We found that sympatric adult thin- and thick-lipped fishes occupy distinct ecological trophic niches. Diet, body shape, head width, pharyngeal jaw size and shape and stable isotope values all differ significantly between the two lip-morphs. The eco-morphological features pharyngeal jaw shape, body shape, stomach contents and stable isotopes (δ15N all show a bimodal distribution of traits, which is compatible with the expectations of an initial stage of ecological speciation under disruptive selection. Genetic differentiation between the thin- and thick-lipped population is weak at mtDNA sequence (FST = 0.018 and absent at nuclear

Magadi tilapia ecological specialization: filling the early gap in the speciation continuum.

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Pinho, Catarina; Faria, Rui

2016-04-01

Cichlid fish are well known for their high speciation rates, which are usually accompanied by spectacular and rapid diversification in eco-morphological and secondary sexual traits. This is best illustrated by the famous repeated explosive radiations in the African Great Lakes Tanganyika, Malawi and Victoria, each lake harbouring several hundreds of mostly endemic species. Correspondingly, cichlids diversified very rapidly in many other lakes across their range. Although the larger radiations, unparalleled in vertebrates, are certainly the most intriguing, they are also the most intricate and difficult to address because of their complex nature. This is where smaller, simpler systems may prove to be the most useful. In this issue of Molecular Ecology, Kavembe et al. (2016) report very recent genetic diversification accompanied by ecological specialization in cichlids of the small and ecologically extreme Lake Magadi, in Kenya. Combining geometric morphometrics, stable isotope analysis, population genomics using RADSeq data and coalescent-based modelling techniques, the authors characterize the eco-morphological differences between genetically distinct populations of Magadi tilapia (Alcolapia grahami), which are consistent with the different environmental conditions they experience, and infer their history of divergence. The simplicity of the focal system and the use of a multidisciplinary approach make this work particularly important for our understanding of the early stages of speciation, in both cichlids and other organisms. © 2016 John Wiley & Sons Ltd.

Ecological and methodological drivers of species’ distribution and phenology responses to climate change

KAUST Repository

Brown, Christopher J.

2015-12-10

Climate change is shifting species’ distribution and phenology. Ecological traits, such as mobility or reproductive mode, explain variation in observed rates of shift for some taxa. However, estimates of relationships between traits and climate responses could be influenced by how responses are measured. We compiled a global dataset of 651 published marine species’ responses to climate change, from 47 papers on distribution shifts and 32 papers on phenology change. We assessed the relative importance of two classes of predictors of the rate of change, ecological traits of the responding taxa and methodological approaches for quantifying biological responses. Methodological differences explained 22% of the variation in range shifts, more than the 7.8% of the variation explained by ecological traits. For phenology change, methodological approaches accounted for 4% of the variation in measurements, whereas 8% of the variation was explained by ecological traits. Our ability to predict responses from traits was hindered by poor representation of species from the tropics, where temperature isotherms are moving most rapidly. Thus, the mean rate of distribution change may be underestimated by this and other global syntheses. Our analyses indicate that methodological approaches should be explicitly considered when designing, analysing and comparing results among studies. To improve climate impact studies, we recommend that: (1) re-analyses of existing time-series state how the existing datasets may limit the inferences about possible climate responses; (2) qualitative comparisons of species’ responses across different studies be limited to studies with similar methodological approaches; (3) meta-analyses of climate responses include methodological attributes as covariates and; (4) that new time series be designed to include detection of early warnings of change or ecologically relevant change. Greater consideration of methodological attributes will improve the

Least square method of estimation of ecological half-lives of radionuclides in sediments

International Nuclear Information System (INIS)

Ranade, A.K.; Pandey, M.; Datta, D.; Ravi, P.M.

2012-01-01

Long term behavior of radionuclides in the environment is an important issue for estimating probable radiological consequences and associated risks. It is also useful for evaluating potential use of contaminated areas and the possible effectiveness of remediation activities. The long term behavior is quantified by means of ecological half life, a parameter that aggregates all processes except radioactive decay which causes a decrease of activity in a specific medium. The process involved in ecological half life depends upon the environmental condition of the medium involved. A fitting model based on least square regression approach was used to evaluate the ecological half life. This least square method has to run several times to evaluate the number of ecological half lives present in the medium for the radionuclide. The case study data considered here is for 137 Cs in Mumbai Harbour Bay. The study shows the trend of 137 Cs over the years at a location in Mumbai Harbour Bay. First iteration model illustrate the ecological half life as 4.94 y and subsequently it passes through a number of runs for more number of ecological half-life present by goodness of fit test. The paper presents a methodology for evaluating ecological half life and exemplifies it with a case study of 137 Cs. (author)

Synergy between Allopatry and Ecology in Population Differentiation and Speciation

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Yann Surget-Groba

2012-01-01

Full Text Available The general diversity pattern of the Caribbean anole radiation has been described in detail; however, the actual mechanisms at the origin of their diversification remain controversial. In particular, the role of ecological speciation, and the relative importance of divergence in allopatry and in parapatry, is debated. We describe the genetic structure of anole populations across lineage contact zones and ecotones to investigate the effect of allopatric divergence, natural selection, and the combination of both factors on population differentiation. Allopatric divergence had no significant impact on differentiation across the lineage boundary, while a clear bimodality in genetic and morphological characters was observed across an ecotone within a single lineage. Critically, the strongest differentiation was observed when allopatry and ecology act together, leading to a sharp reduction in gene flow between two lineages inhabiting different habitats. We suggest that, for Caribbean anoles to reach full speciation, a synergistic combination of several historical and ecological factors may be requisite.

A National Approach to Quantify and Map Biodiversity ...

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Ecosystem services, i.e., "services provided to humans from natural systems," have become a key issue of this century in resource management, conservation planning, human well-being, and environmental decision analysis. Mapping and quantifying ecosystem services have become strategic national interests for integrating ecology with economics to help understand the effects of human policies and actions and their subsequent impacts on both ecosystem function and human welfare. The degradation of natural ecosystems and climate variation impact the environment and society by affecting ecological integrity and ecosystems’ capacity to provide critical services (i.e., the contributions of ecosystems to human well-being). These challenges will require complex management decisions that can often involve significant trade-offs between societal desires and environmental needs. Evaluating trade-offs in terms of ecosystem services and human well-being provides an intuitive and comprehensive way to assess the broad implications of our decisions and to help shape policies that enhance environmental and social sustainability. In answer to this challenge, the U.S. government has created a partnership among the U.S. Environmental Protection Agency, other Federal agencies, academic institutions, and, Non-Governmental Organizations to develop the EnviroAtlas, an online Decision Support Tool that allows users (e.g., planners, policy-makers, resource managers, NGOs, private indu

Insights from ecological niche modeling on the taxonomic distinction and niche differentiation between the black-spotted and red-spotted tokay geckoes (Gekko gecko).

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Zhang, Yueyun; Chen, Chongtao; Li, Li; Zhao, Chengjian; Chen, Weicai; Huang, Yong

2014-09-01

The black-spotted tokay and the red-spotted tokay are morphologically distinct and have largely allopatric distributions. The black-spotted tokay is characterized by a small body size and dark skin with sundry spots, while the red-spotted tokay has a relatively large body size and red spots. Based on morphological, karyotypic, genetic, and distribution differences, recent studies suggested their species status; however, their classifications remain controversial, and additional data such as ecological niches are necessary to establish firm hypotheses regarding their taxonomic status. We reconstructed their ecological niches models using climatic and geographic data. We then performed niche similarity tests (niche identity and background tests) and point-based analyses to explore whether ecological differentiation has occurred, and whether such differences are sufficient to explain the maintenance of their separate segments of environmental ranges. We found that both niche models of the black- and the red-spotted tokay had a good fit and a robust performance, as indicated by the high area under the curve (AUC) values ("black" = 0.982, SD = ± 0.002, "red" = 0.966 ± 0.02). Significant ecological differentiation across the entire geographic range was found, indicating that the involvement of ecological differentiation is important for species differentiation. Divergence along the environmental axes is highly associated with climatic conditions, with isothermality being important for the "black" form, while temperature seasonality, precipitation of warmest quarter, and annual temperature range together being important for the "red" form. These factors are likely important factors in niche differentiation between the two forms, which result in morphological replacement. Overall, beside morphological and genetic differentiation information, our results contribute to additional insights into taxonomic distinction and niche differentiation between the black- and the red

Genetic, ecological and morphological divergence between populations of the endangered Mexican Sheartail hummingbird (Doricha eliza.

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Yuyini Licona-Vera

Full Text Available The Mexican Sheartail (Doricha eliza, an endangered hummingbird, is endemic to Mexico where two populations have a disjunct distribution. One population is distributed along the northern tip of the Yucatan Peninsula whereas the other is mostly restricted to central Veracruz. Despite their disjunct distribution, previous work has failed to detect morphological or behavioral differences between these populations. Here we use variation in morphology, mtDNA and nuDNA sequences to determine the degree of morphological and molecular divergence between populations, their divergence time, and historical demography. We use species distribution modeling and niche divergence tests to infer the relative roles of vicariance and dispersal in driving divergence in the genus. Our Bayesian and maximum likelihood phylogenetic analyses revealed that Doricha eliza populations form a monophyletic clade and support their sister relationship with D. enicura. We found marked genetic differentiation, with reciprocal monophyly of haplotypes and highly restricted gene flow, supporting a history of isolation over the last 120,000 years. Genetic divergence between populations is consistent with the lack of overlap in environmental space and slight morphological differences between males. Our findings indicate that the divergence of the Veracruz and Yucatan populations is best explained by a combination of a short period of isolation exacerbated by subsequent divergence in climate conditions, and that rather than vicariance, the two isolated ranges of D. eliza are the product of recent colonization and divergence in isolation.

A Rapid Method to Score Stream Reaches Based on the Overall Performance of Their Main Ecological Functions

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Rowe, David K.; Parkyn, Stephanie; Quinn, John; Collier, Kevin; Hatton, Chris; Joy, Michael K.; Maxted, John; Moore, Stephen

2009-06-01

A method was developed to score the ecological condition of first- to third-order stream reaches in the Auckland region of New Zealand based on the performance of their key ecological functions. Such a method is required by consultants and resource managers to quantify the reduction in ecological condition of a modified stream reach relative to its unmodified state. This is a fundamental precursor for the determination of fair environmental compensation for achieving no-net-loss in overall stream ecological value. Field testing and subsequent use of the method indicated that it provides a useful measure of ecological condition related to the performance of stream ecological functions. It is relatively simple to apply compared to a full ecological study, is quick to use, and allows identification of the degree of impairment of each of the key ecological functions. The scoring system was designed so that future improvements in the measurement of stream functions can be incorporated into it. Although the methodology was specifically designed for Auckland streams, the principles can be readily adapted to other regions and stream types.

The Diatom Anorthoneis dulcis Hein from Southern Brazil: Morphology and Ecology

International Nuclear Information System (INIS)

Marines, G.; Marciana, T.D.

2007-01-01

A new geographic locality for Anorthoneis dulcis is reported. The paper describes the distribution and relative abundance of A. dulcis in Lagoa dos Patos lagoon (a lagoon in Rio Grande do Sul state, Brazil) from samples collected between 2004 and 2005, and shows that this rare species is present all year round. This study extends the species distribution to South America indicating that the species can thrive on sand grains in lentic estuarine, and freshwater areas. It widens the range of tolerance to environmental parameters. The valve fine structure, morphology, and dimensions are in agreement with the original diagnosis.

Calibrating a numerical model's morphology using high-resolution spatial and temporal datasets from multithread channel flume experiments.

Science.gov (United States)

Javernick, L.; Bertoldi, W.; Redolfi, M.

2017-12-01

Accessing or acquiring high quality, low-cost topographic data has never been easier due to recent developments of the photogrammetric techniques of Structure-from-Motion (SfM). Researchers can acquire the necessary SfM imagery with various platforms, with the ability to capture millimetre resolution and accuracy, or large-scale areas with the help of unmanned platforms. Such datasets in combination with numerical modelling have opened up new opportunities to study river environments physical and ecological relationships. While numerical models overall predictive accuracy is most influenced by topography, proper model calibration requires hydraulic data and morphological data; however, rich hydraulic and morphological datasets remain scarce. This lack in field and laboratory data has limited model advancement through the inability to properly calibrate, assess sensitivity, and validate the models performance. However, new time-lapse imagery techniques have shown success in identifying instantaneous sediment transport in flume experiments and their ability to improve hydraulic model calibration. With new capabilities to capture high resolution spatial and temporal datasets of flume experiments, there is a need to further assess model performance. To address this demand, this research used braided river flume experiments and captured time-lapse observed sediment transport and repeat SfM elevation surveys to provide unprecedented spatial and temporal datasets. Through newly created metrics that quantified observed and modeled activation, deactivation, and bank erosion rates, the numerical model Delft3d was calibrated. This increased temporal data of both high-resolution time series and long-term temporal coverage provided significantly improved calibration routines that refined calibration parameterization. Model results show that there is a trade-off between achieving quantitative statistical and qualitative morphological representations. Specifically, statistical

Nuclear markers reveal that inter-lake cichlids' similar morphologies do not reflect similar genealogy.

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Kassam, Daud; Seki, Shingo; Horic, Michio; Yamaoka, Kosaku

2006-08-01

The apparent inter-lake morphological similarity among East African Great Lakes' cichlid species/genera has left evolutionary biologists asking whether such similarity is due to sharing of common ancestor or mere convergent evolution. In order to answer such question, we first used Geometric Morphometrics, GM, to quantify morphological similarity and then subsequently used Amplified Fragment Length Polymorphism, AFLP, to determine if similar morphologies imply shared ancestry or convergent evolution. GM revealed that not all presumed morphological similar pairs were indeed similar, and the dendrogram generated from AFLP data indicated distinct clusters corresponding to each lake and not inter-lake morphological similar pairs. Such results imply that the morphological similarity is due to convergent evolution and not shared ancestry. The congruency of GM and AFLP generated dendrograms imply that GM is capable of picking up phylogenetic signal, and thus GM can be potential tool in phylogenetic systematics.

Marine Ecological Footprint of Italian Mediterranean Fisheries

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Federica de Leo

2014-10-01

Full Text Available The capacity of marine and coastal ecosystems to sustain seafood production and consumption is seldom accounted for and is not included in the signals that guide economic development. In this article, we review estimates of marine and coastal areas aimed at sustaining catches for seafood consumption. The aim of this paper is the assessment of the interactions between the environment, intended as a set of ecological subsystems in natural equilibrium, including the marine ecosystem, and the process of fisheries systems. In particular we analyze fisheries in Italy, which is the third biggest economy and the greatest consumer of seafood in the Eurozone, conducting an in-depth analysis of the Marine Ecological Footprint (MEF that evaluates the marine ecosystem area exploited by human populations to supply seafood and other marine products and services. The positioning of Italian fisheries shows a level of sustainability next to the threshold value. The analysis in the present study highlights the importance of absolute indicators in providing rough estimates about human dependence on ecological systems and recognizes the importance of those indicators, such as the Marine Footprint (expressed in % of Primary Production Required/Primary Production, in ensuring a high level of precision and accuracy in quantifying human activity impact on the environment.

Ecological response of a multi-purpose river development project using macro-invertebrates richness and fish habitat value[Dissertation 3807

Energy Technology Data Exchange (ETDEWEB)

Pellaud, M.

2007-05-15

It has been acknowledged that river morphology and hydrology have been intensively altered due to the anthropic demands in floodplain land use and management, flood protection, promotion of navigability or energy production. Rivers were transformed in water highways, having lost contact with their surrounding floodplain as well as the plethora of ecological processes and occupants once thriving in these ecotonal zones. The identification of this emerging threat of morphological and hydrological alteration on ecological integrity adds further complexity in the exploitation of hydrosystem resources. These resources are heavily coveted and guarded by different lobbies each having strategic views on future project development. Stakeholders may want to promote hydro-electricity, ecologists a natural reserve, communes may wish to have an increased flood protection and leisure promoters a nautical center. As a result, the proposition of a river development project is certain to face opposition of one party or the other. The motivations of this dissertation are anchored in this context, where various and sometimes conflicting potentials for hydrosystem exploitation remain. This works aims at contributing scientifically to an innovative approach at the conception phase of a multi-purpose river development project by developing the ecological module to be implemented in the general project's optimizer. The SYNERGIE project hypothesis is that it should be possible to identify a synergetic pattern joining the interests of ecological integrity, flood safety, energy production and leisure development. Such a multi-objective river development project would stand more chance of acceptance. This dissertation focuses on the ecological aspects of such a river development project and an application on the regulated Swiss Upper Rhone River. Is expected an ecological answer to a river development project design / management which has to be compatible with Heller's Heller (2007

Integrating Economic and Ecological Benchmarking for a Sustainable Development of Hydropower

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Philipp Emanuel Hirsch

2016-08-01

Full Text Available Hydropower reservoirs play an increasingly important role for the global electricity supply. Reservoirs are anthropogenically-dominated ecosystems because hydropower operations induce artificial water level fluctuations (WLF that exceed natural fluctuations in frequency and amplitude. These WLF have detrimental ecological effects, which can be quantified as losses to ecosystem primary production due to lake bottoms that fall dry. To allow for a sustainable development of hydropower, these “ecological costs” of WLF need to be weighed against the “economic benefits” of hydropower that can balance and store intermittent renewable energy. We designed an economic hydropower operation model to derive WLF in large and small reservoirs for three different future energy market scenarios and quantified the according losses in ecosystem primary production in semi-natural outdoor experiments. Our results show that variations in market conditions affect WLF differently in small and large hydropower reservoirs and that increasing price volatility magnified WLF and reduced primary production. Our model allows an assessment of the trade-off between the objectives of preserving environmental resources and economic development, which lies at the core of emerging sustainability issues.

Neighborhood Variation of Sustainable Urban Morphological Characteristics

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Chen, Si; Stimson, Robert

2018-01-01

Compact cities and their urban forms have implications on sustainable city development because of high density urban settlement, increased accessibility, and a balanced land use mix. This paper uses quantitative means of understanding urban morphological characteristics with reference to the differing qualities of the urban form (i.e., street patterns, building volumes, land uses and greenery). The results, based on 89 neighborhood communities of Hong Kong, show varying degrees of regional differences in the urban built form supported by numerical statistics and graphical illustrations. This paper offers empirical evidence on some morphological characteristics that can be estimated objectively using modern geospatial technologies and applied universally to inform urban planning. However, more studies linking these quantifiable measures of the physical form with sustainable urban living are needed to account for human comfort in the totality of environmental, social, and economic responsibilities. PMID:29518956

Neighborhood Variation of Sustainable Urban Morphological Characteristics

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Poh-Chin Lai

2018-03-01

Full Text Available Compact cities and their urban forms have implications on sustainable city development because of high density urban settlement, increased accessibility, and a balanced land use mix. This paper uses quantitative means of understanding urban morphological characteristics with reference to the differing qualities of the urban form (i.e., street patterns, building volumes, land uses and greenery. The results, based on 89 neighborhood communities of Hong Kong, show varying degrees of regional differences in the urban built form supported by numerical statistics and graphical illustrations. This paper offers empirical evidence on some morphological characteristics that can be estimated objectively using modern geospatial technologies and applied universally to inform urban planning. However, more studies linking these quantifiable measures of the physical form with sustainable urban living are needed to account for human comfort in the totality of environmental, social, and economic responsibilities.

Neighborhood Variation of Sustainable Urban Morphological Characteristics.

Science.gov (United States)

Lai, Poh-Chin; Chen, Si; Low, Chien-Tat; Cerin, Ester; Stimson, Robert; Wong, Pui Yun Paulina

2018-03-07

Compact cities and their urban forms have implications on sustainable city development because of high density urban settlement, increased accessibility, and a balanced land use mix. This paper uses quantitative means of understanding urban morphological characteristics with reference to the differing qualities of the urban form (i.e., street patterns, building volumes, land uses and greenery). The results, based on 89 neighborhood communities of Hong Kong, show varying degrees of regional differences in the urban built form supported by numerical statistics and graphical illustrations. This paper offers empirical evidence on some morphological characteristics that can be estimated objectively using modern geospatial technologies and applied universally to inform urban planning. However, more studies linking these quantifiable measures of the physical form with sustainable urban living are needed to account for human comfort in the totality of environmental, social, and economic responsibilities.

In Vitro Morphological Characteristics of Pyrenophora tritici-repentis Isolates from Several Algerian Agro-Ecological Zones

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Hamida Benslimane

2017-04-01

Full Text Available Tan spot caused by the fungus Pyrenophora triticirepentis is a serious disease of wheat, which is on increase in recent years in Mediterranean region. In the field this fungus produces a diamond-shaped necrotic lesions with a yellow halo on wheat foliage. The objective of this study was to characterize and compare several monospore isolates of P. tritici-repentis collected from different infected wheat fields in various locations of Algeria, and find the morphological differences between them, if any. The results revealed wide morphologically variation among the isolates based on colony colors and texture, mycelial radial growth and conidial size.

Morphological appearance manifolds for group-wise morphometric analysis.

Science.gov (United States)

Lian, Nai-Xiang; Davatzikos, Christos

2011-12-01

Computational anatomy quantifies anatomical shape based on diffeomorphic transformations of a template. However, different templates warping algorithms, regularization parameters, or templates, lead to different representations of the same exact anatomy, raising a uniqueness issue: variations of these parameters are confounding factors as they give rise to non-unique representations. Recently, it has been shown that learning the equivalence class derived from the multitude of representations of a given anatomy can lead to improved and more stable morphological descriptors. Herein, we follow that approach, by approximating this equivalence class of morphological descriptors by a (nonlinear) morphological appearance manifold fitting to the data via a locally linear model. Our approach parallels work in the computer vision field, in which variations lighting, pose and other parameters lead to image appearance manifolds representing the exact same figure in different ways. The proposed framework is then used for group-wise registration and statistical analysis of biomedical images, by employing a minimum variance criterion to perform manifold-constrained optimization, i.e. to traverse each individual's morphological appearance manifold until group variance is minimal. The hypothesis is that this process is likely to reduce aforementioned confounding effects and potentially lead to morphological representations reflecting purely biological variations, instead of variations introduced by modeling assumptions and parameter settings. Copyright © 2011 Elsevier B.V. All rights reserved.

Ecological changes in Coyotes (Canis latrans in response to the ice age megafaunal extinctions.

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Julie A Meachen

Full Text Available Coyotes (Canis latrans are an important species in human-inhabited areas. They control pests and are the apex predators in many ecosystems. Because of their importance it is imperative to understand how environmental change will affect this species. The end of the Pleistocene Ice Age brought with it many ecological changes for coyotes and here we statistically determine the changes that occurred in coyotes, when these changes occurred, and what the ecological consequences were of these changes. We examined the mandibles of three coyote populations: Pleistocene Rancho La Brean (13-29 Ka, earliest Holocene Rancho La Brean (8-10 Ka, and Recent from North America, using 2D geometric morphometrics to determine the morphological differences among them. Our results show that these three populations were morphologically distinct. The Pleistocene coyotes had an overall robust mandible with an increased shearing arcade and a decreased grinding arcade, adapted for carnivory and killing larger prey; whereas the modern populations show a gracile morphology with a tendency toward omnivory or grinding. The earliest Holocene populations are intermediate in morphology and smallest in size. These findings indicate that a niche shift occurred in coyotes at the Pleistocene/Holocene boundary - from a hunter of large prey to a small prey/more omnivorous animal. Species interactions between Canis were the most likely cause of this transition. This study shows that the Pleistocene extinction event affected species that did not go extinct as well as those that did.

Ecology and evolution of mammalian biodiversity.

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Jones, Kate E; Safi, Kamran

2011-09-12

Mammals have incredible biological diversity, showing extreme flexibility in eco-morphology, physiology, life history and behaviour across their evolutionary history. Undoubtedly, mammals play an important role in ecosystems by providing essential services such as regulating insect populations, seed dispersal and pollination and act as indicators of general ecosystem health. However, the macroecological and macroevolutionary processes underpinning past and present biodiversity patterns are only beginning to be explored on a global scale. It is also particularly important, in the face of the global extinction crisis, to understand these processes in order to be able to use this knowledge to prevent future biodiversity loss and loss of ecosystem services. Unfortunately, efforts to understand mammalian biodiversity have been hampered by a lack of data. New data compilations on current species' distributions, ecologies and evolutionary histories now allow an integrated approach to understand this biodiversity. We review and synthesize these new studies, exploring the past and present ecology and evolution of mammalian biodiversity, and use these findings to speculate about the mammals of our future.

Ecology and evolution of mammalian biodiversity

Science.gov (United States)

Jones, Kate E.; Safi, Kamran

2011-01-01

Mammals have incredible biological diversity, showing extreme flexibility in eco-morphology, physiology, life history and behaviour across their evolutionary history. Undoubtedly, mammals play an important role in ecosystems by providing essential services such as regulating insect populations, seed dispersal and pollination and act as indicators of general ecosystem health. However, the macroecological and macroevolutionary processes underpinning past and present biodiversity patterns are only beginning to be explored on a global scale. It is also particularly important, in the face of the global extinction crisis, to understand these processes in order to be able to use this knowledge to prevent future biodiversity loss and loss of ecosystem services. Unfortunately, efforts to understand mammalian biodiversity have been hampered by a lack of data. New data compilations on current species' distributions, ecologies and evolutionary histories now allow an integrated approach to understand this biodiversity. We review and synthesize these new studies, exploring the past and present ecology and evolution of mammalian biodiversity, and use these findings to speculate about the mammals of our future. PMID:21807728

Scrambled eggs: mechanical forces as ecological factors in early development.

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Moore, Steven W

2003-01-01

Many ecological interactions involve, at some level, mechanical forces and the movements or structural deformations they produce. Although the most familiar examples involve the functional morphology of adult structures, all life history stages (not just the adults) are subject to the laws of physics. Moreover, the success of every lineage depends on the success of every life history stage (again, not just the adults). Therefore, insights gained by using mechanical engineering principles and techniques to study ecological interactions between gametes, embryos, larvae, and their environment are essential to a well-rounded understanding of development, ecology, and evolution. Here I draw on examples from the literature and my own research to illustrate ways in which mechanical forces in the environment shape development. These include mechanical forces acting as selective factors (e.g., when coral gamete size and shape interact with turbulent water flow to determine fertilization success) and as developmental cues (e.g., when plant growth responds to gravity or bone growth responds to mechanical loading). I also examine the opposite cause-and-effect relationship by considering examples in which the development of organisms impacts ecologically relevant mechanical forces. Finally, I discuss the potential for ecological pattern formation as a result of feedback loops created by such bidirectional interactions between developmental processes and mechanical forces in the environment.

Molecular Ecological Insights into Neotropical Bird-Tick Interactions.

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Matthew J Miller

Full Text Available In the tropics, ticks parasitize many classes of vertebrate hosts. However, because many tropical tick species are only identifiable in the adult stage, and these adults usually parasitize mammals, most attention on the ecology of tick-host interactions has focused on mammalian hosts. In contrast, immature Neotropical ticks are often found on wild birds, yet difficulties in identifying immatures hinder studies of birds' role in tropical tick ecology and tick-borne disease transmission. In Panama, we found immature ticks on 227 out of 3,498 individually-sampled birds representing 93 host species (24% of the bird species sampled, and 13% of the Panamanian land bird fauna. Tick parasitism rates did not vary with rainfall or temperature, but did vary significantly with several host ecological traits. Likewise, Neotropical-Nearctic migratory birds were significantly less likely to be infested than resident species. Using a molecular library developed from morphologically-identified adult ticks specifically for this study, we identified eleven tick species parasitizing birds, indicating that a substantial portion of the Panamanian avian species pool is parasitized by a diversity of tick species. Tick species that most commonly parasitized birds had the widest diversity of avian hosts, suggesting that immature tick species are opportunistic bird parasites. Although certain avian ecological traits are positively associated with parasitism, we found no evidence that individual tick species show specificity to particular avian host ecological traits. Finally, our data suggest that the four principal vectors of Rocky Mountain Spotted Fever in the Neotropics rarely, if ever, parasitize Panamanian birds. However, other tick species that harbor newly-discovered rickettsial parasites of unknown pathogenicity are frequently found on these birds. Given our discovery of broad interaction between Panamanian tick and avian biodiversity, future work on tick ecology

Molecular Ecological Insights into Neotropical Bird-Tick Interactions.

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Miller, Matthew J; Esser, Helen J; Loaiza, Jose R; Herre, Edward Allen; Aguilar, Celestino; Quintero, Diomedes; Alvarez, Eric; Bermingham, Eldredge

2016-01-01

In the tropics, ticks parasitize many classes of vertebrate hosts. However, because many tropical tick species are only identifiable in the adult stage, and these adults usually parasitize mammals, most attention on the ecology of tick-host interactions has focused on mammalian hosts. In contrast, immature Neotropical ticks are often found on wild birds, yet difficulties in identifying immatures hinder studies of birds' role in tropical tick ecology and tick-borne disease transmission. In Panama, we found immature ticks on 227 out of 3,498 individually-sampled birds representing 93 host species (24% of the bird species sampled, and 13% of the Panamanian land bird fauna). Tick parasitism rates did not vary with rainfall or temperature, but did vary significantly with several host ecological traits. Likewise, Neotropical-Nearctic migratory birds were significantly less likely to be infested than resident species. Using a molecular library developed from morphologically-identified adult ticks specifically for this study, we identified eleven tick species parasitizing birds, indicating that a substantial portion of the Panamanian avian species pool is parasitized by a diversity of tick species. Tick species that most commonly parasitized birds had the widest diversity of avian hosts, suggesting that immature tick species are opportunistic bird parasites. Although certain avian ecological traits are positively associated with parasitism, we found no evidence that individual tick species show specificity to particular avian host ecological traits. Finally, our data suggest that the four principal vectors of Rocky Mountain Spotted Fever in the Neotropics rarely, if ever, parasitize Panamanian birds. However, other tick species that harbor newly-discovered rickettsial parasites of unknown pathogenicity are frequently found on these birds. Given our discovery of broad interaction between Panamanian tick and avian biodiversity, future work on tick ecology and the dynamics of

Validating DNA barcodes: A non-destructive extraction protocol enables simultaneous vouchering of DNA and morphological vouchers

Science.gov (United States)

Morphology-based keys support accurate identification of many taxa. However, identification can be difficult for taxa that are not well studied, very small, members of cryptic species complexes, or represented by immature stages. For such cases, DNA barcodes may provide diagnostic characters. Ecolog...

Belowground competition from overstory trees influences Douglas-fir sapling morphology in thinned stands

Science.gov (United States)

Warren D. Devine; Timothy B. Harrington

2009-01-01

We evaluated effects of belowground competition on morphology of naturally established coast Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) saplings in 60- to 80-year-old thinned Douglas-fir stands in southwestern Washington. We separately quantified belowground competition from overstory and understory sources...

Ecologizing Our Cities: A Particular, Process-Function View of Southern California, from within Complexity

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Ashwani Vasishth

2015-08-01

Full Text Available Cities, as the quintessential socio-technological artifacts of human civilization, are seen to set us apart from nature. But an ecosystem view from nested scale-hierarchical process-function ecology shows us that cities are best seen as the emergent and nodal end points of interactive flows of matter, energy and information. From within such a view, a clear need emerges to ecologize our cities by better integrating them back with nature. Arguing from such an ecosystem approach to depicting reality, this paper proposes that tracing the processes and functions which constitute the morphology of the city leads us to articulate an urban ecology that incorporates heat island mitigations, urban forestry, and ecological landscape management (taken both as the introduction of native vegetation and the insertion of increased proportions of pervious paving, all considered within the framework of an integrative ecosystem approach to land use planning. More importantly, such an approach to urban ecology is useful because, as a mode of intervention, it rests on—indeed, requires—an acknowledgement in ecological planning of the often amorphous and usually only indirectly sensible atmospheric, biogeochemical and hydrological processes and functions.

Marine Ecological Environment Management Based on Ecological Compensation Mechanisms

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Qunzhen Qu

2016-12-01

Full Text Available The level of marine environmental management is a key factor in the successful implementation of marine power strategies. The improvement in management levels of marine environments requires innovation in marine management. In other words, the transformation of marine environmental management into marine ecological environment management must be done in order to achieve sustainable development of the marine economy. As an environmental economic policy that combines both administrative and market measures, ecological compensation mechanisms have significant advantages in marine ecological environment management. Based on the study of the current development of ecological compensation mechanisms in China, through the analysis of the connotation of marine ecological civilization, existing marine ecological protection practices and marine environmental management methods, this paper posits that the current marine ecological environment management in China should be established on the basis of ecological compensation mechanisms. At present, a lack of laws and regulations for overall marine ecological environment management is the key factor restricting the practice of marine ecological environment management. Therefore, it is necessary to explore the current path of marine ecological environment management in China from the perspective of the construction of legal system of ecological compensation law, the establishment of ecological compensation fees, ecological taxes and ecological compensation fund systems, and the clear status for a marine ecological management and supervision body.

Calculating background levels for ecological risk parameters in toxic harbor sediment

Science.gov (United States)

Leadon, C.J.; McDonnell, T.R.; Lear, J.; Barclift, D.

2007-01-01

Establishing background levels for biological parameters is necessary in assessing the ecological risks from harbor sediment contaminated with toxic chemicals. For chemicals in sediment, the term contaminated is defined as having concentrations above background and significant human health or ecological risk levels. For biological parameters, a site could be considered contaminated if levels of the parameter are either more or less than the background level, depending on the specific parameter. Biological parameters can include tissue chemical concentrations in ecological receptors, bioassay responses, bioaccumulation levels, and benthic community metrics. Chemical parameters can include sediment concentrations of a variety of potentially toxic chemicals. Indirectly, contaminated harbor sediment can impact shellfish, fish, birds, and marine mammals, and human populations. This paper summarizes the methods used to define background levels for chemical and biological parameters from a survey of ecological risk investigations of marine harbor sediment at California Navy bases. Background levels for regional biological indices used to quantify ecological risks for benthic communities are also described. Generally, background stations are positioned in relatively clean areas exhibiting the same physical and general chemical characteristics as nearby areas with contaminated harbor sediment. The number of background stations and the number of sample replicates per background station depend on the statistical design of the sediment ecological risk investigation, developed through the data quality objective (DQO) process. Biological data from the background stations can be compared to data from a contaminated site by using minimum or maximum background levels or comparative statistics. In Navy ecological risk assessments (ERA's), calculated background levels and appropriate ecological risk screening criteria are used to identify sampling stations and sites with contaminated

Quantifying Matter

CERN Document Server

Angelo, Joseph A

2011-01-01

Quantifying Matter explains how scientists learned to measure matter and quantify some of its most fascinating and useful properties. It presents many of the most important intellectual achievements and technical developments that led to the scientific interpretation of substance. Complete with full-color photographs, this exciting new volume describes the basic characteristics and properties of matter. Chapters include:. -Exploring the Nature of Matter. -The Origin of Matter. -The Search for Substance. -Quantifying Matter During the Scientific Revolution. -Understanding Matter's Electromagnet

Beyond positivist ecology: toward an integrated ecological ethics.

Science.gov (United States)

Norton, Bryan G

2008-12-01

A post-positivist understanding of ecological science and the call for an "ecological ethic" indicate the need for a radically new approach to evaluating environmental change. The positivist view of science cannot capture the essence of environmental sciences because the recent work of "reflexive" ecological modelers shows that this requires a reconceptualization of the way in which values and ecological models interact in scientific process. Reflexive modelers are ecological modelers who believe it is appropriate for ecologists to examine the motives for their choices in developing models; this self-reflexive approach opens the door to a new way of integrating values into public discourse and to a more comprehensive approach to evaluating ecological change. This reflexive building of ecological models is introduced through the transformative simile of Aldo Leopold, which shows that learning to "think like a mountain" involves a shift in both ecological modeling and in values and responsibility. An adequate, interdisciplinary approach to ecological valuation, requires a re-framing of the evaluation questions in entirely new ways, i.e., a review of the current status of interdisciplinary value theory with respect to ecological values reveals that neither of the widely accepted theories of environmental value-neither economic utilitarianism nor intrinsic value theory (environmental ethics)-provides a foundation for an ecologically sensitive evaluation process. Thus, a new, ecologically sensitive, and more comprehensive approach to evaluating ecological change would include an examination of the metaphors that motivate the models used to describe environmental change.

Middle ear cavity morphology is consistent with an aquatic origin for testudines.

Directory of Open Access Journals (Sweden)

Katie L Willis

Full Text Available The position of testudines in vertebrate phylogeny is being re-evaluated. At present, testudine morphological and molecular data conflict when reconstructing phylogenetic relationships. Complicating matters, the ecological niche of stem testudines is ambiguous. To understand how turtles have evolved to hear in different environments, we examined middle ear morphology and scaling in most extant families, as well as some extinct species, using 3-dimensional reconstructions from micro magnetic resonance (MR and submillimeter computed tomography (CT scans. All families of testudines exhibited a similar shape of the bony structure of the middle ear cavity, with the tympanic disk located on the rostrolateral edge of the cavity. Sea Turtles have additional soft tissue that fills the middle ear cavity to varying degrees. When the middle ear cavity is modeled as an air-filled sphere of the same volume resonating in an underwater sound field, the calculated resonances for the volumes of the middle ear cavities largely fell within testudine hearing ranges. Although there were some differences in morphology, there were no statistically significant differences in the scaling of the volume of the bony middle ear cavity with head size among groups when categorized by phylogeny and ecology. Because the cavity is predicted to resonate underwater within the testudine hearing range, the data support the hypothesis of an aquatic origin for testudines, and function of the middle ear cavity in underwater sound detection.

[Regional ecological construction and mission of landscape ecology].

Science.gov (United States)

Xiao, Duning; Xie, Fuju; Wei, Jianbing

2004-10-01

The eco-construction on regional and landscape scale is the one which can be used to specific landscape and intercrossing ecosystem in specific region including performing scientific administration of ecosystem and optimizing environmental function. Recently, the government has taken a series of significant projects into action, such as national forest protection item, partly forest restoration, and adjustment of water, etc. Enforcing regional eco-construction and maintaining the ecology security of the nation have become the strategic requisition. In various regions, different eco-construction should be applied, for example, performing ecological safeguard measure in ecological sensitive zone, accommodating the ecological load in ecological fragile zone, etc., which can control the activities of human being, so that, sustainable development can be reached. Facing opportunity and challenge in the development of landscape ecology, we have some key topics: landscape pattern of ecological security, land use and ecological process, landscape changes under human activity stress, quantitative evaluation of the influence on human being activities, evaluation of zonal ecological security and advance warning of ecological risk, and planning and optimizing of model in landscape eco-construction.

POPs, Fatty acids, lipid and Stable Isotopes data - The behavioral ecology of deep-diving odontocetes in the Bahamas

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National Oceanic and Atmospheric Administration, Department of Commerce — This project will use a unique set of individual-based data to quantify and model the behavioral ecology of six Department of Defense priority cetacean species in...

Integrating evo-devo with ecology for a better understanding of phenotypic evolution.

Science.gov (United States)

Santos, M Emília; Berger, Chloé S; Refki, Peter N; Khila, Abderrahman

2015-11-01

Evolutionary developmental biology (evo-devo) has provided invaluable contributions to our understanding of the mechanistic relationship between genotypic and phenotypic change. Similarly, evolutionary ecology has greatly advanced our understanding of the relationship between the phenotype and the environment. To fully understand the evolution of organismal diversity, a thorough integration of these two fields is required. This integration remains highly challenging because model systems offering a rich ecological and evolutionary background, together with the availability of developmental genetic tools and genomic resources, are scarce. In this review, we introduce the semi-aquatic bugs (Gerromorpha, Heteroptera) as original models well suited to study why and how organisms diversify. The Gerromorpha invaded water surfaces over 200 mya and diversified into a range of remarkable new forms within this new ecological habitat. We summarize the biology and evolutionary history of this group of insects and highlight a set of characters associated with the habitat change and the diversification that followed. We further discuss the morphological, behavioral, molecular and genomic tools available that together make semi-aquatic bugs a prime model for integration across disciplines. We present case studies showing how the implementation and combination of these approaches can advance our understanding of how the interaction between genotypes, phenotypes and the environment drives the evolution of distinct morphologies. Finally, we explain how the same set of experimental designs can be applied in other systems to address similar biological questions. © The Author 2015. Published by Oxford University Press.

THE MORPHOLOGICAL BASIS FOR OLFACTORY PERCEPTION OF STEROIDS DUING AGONISTIC BEHAVIOR IN LOBSTER: PRELIMINARY EXPERIMENTS

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The morphological basis for olfactory perception of steroids during agonistic behavior in lobsters: preliminary experiments. Borsay Horowitz, DJ1, Kass-Simon, G2, Coglianese, D2, Martin, L2, Boseman, M2, Cromarty, S3, Randall, K3, Fini, A.3 1US EPA, NHEERL, ORD, Atlantic Ecology...

Observations on the Morphology, Pollination and Cultivation of Coco de Mer (Lodoicea maldivica (J F Gmel.) Pers., Palmae)

OpenAIRE

Blackmore, Stephen; Chin, See-Chung; Chong Seng, Lindsay; Christie, Frieda; Inches, Fiona; Winda Utami, Putri; Watherston, Neil; Wortley, Alexandra H.

2012-01-01

We present a range of observations on the reproductive morphology, pollination biology and cultivation of Lodoicea maldivica (coco de mer), an endangered species with great ecological, economic and cultural importance. We review the history of study of this charismatic species. Morphological studies of the male inflorescence indicate its importance as a year-round food source to the Seychelles fauna. In situ observations suggest a number of potential biotic and abiotic pollination mechanisms ...

Combined ecological risks of nitrogen and phosphorus in European freshwaters

International Nuclear Information System (INIS)

Azevedo, Ligia B.; Zelm, Rosalie van; Leuven, Rob S.E.W.; Hendriks, A. Jan; Huijbregts, Mark A.J.

2015-01-01

Eutrophication is a key water quality issue triggered by increasing nitrogen (N) and phosphorus (P) levels and potentially posing risks to freshwater biota. We predicted the probability that an invertebrate species within a community assemblage becomes absent due to nutrient stress as the ecological risk (ER) for European lakes and streams subjected to N and P pollution from 1985 to 2011. The ER was calculated as a function of species-specific tolerances to NO 3 − and total P concentrations and water quality monitoring data. Lake and stream ER averaged 50% in the last monitored year (i.e. 2011) and we observed a decrease by 22% and 38% in lake and stream ER (respectively) of river basins since 1985. Additionally, the ER from N stress surpassed that of P in both freshwater systems. The ER can be applied to identify river basins most subjected to eutrophication risks and the main drivers of impacts. - Highlights: • Ecological risk was estimated as response additions of N and P. • The risk posed by N stress is higher than that by P in European freshwaters. • Ecological risks have remained unchanged in most European river basins. - Quantifying the ecological risk of invertebrate losses due to N and P pollution

Resource use and food self-sufficiency at farm scale within two agro-ecological zones of Rwanda

NARCIS (Netherlands)

Bucagu, C.; Vanlauwe, B.; Wijk, van M.T.; Giller, K.E.

2014-01-01

Resource use and management are major determinants of the food self-sufficiency of smallholder farmers in sub-Saharan Africa. A study was conducted in Rwanda in two contrasting agro-ecological zones (Central plateau and Buberuka) to characterise farms, quantify their resource flows, and evaluate the

Genetic signatures of ecological diversity along an urbanization gradient.

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Kelly, Ryan P; O'Donnell, James L; Lowell, Natalie C; Shelton, Andrew O; Samhouri, Jameal F; Hennessey, Shannon M; Feist, Blake E; Williams, Gregory D

2016-01-01

Despite decades of work in environmental science and ecology, estimating human influences on ecosystems remains challenging. This is partly due to complex chains of causation among ecosystem elements, exacerbated by the difficulty of collecting biological data at sufficient spatial, temporal, and taxonomic scales. Here, we demonstrate the utility of environmental DNA (eDNA) for quantifying associations between human land use and changes in an adjacent ecosystem. We analyze metazoan eDNA sequences from water sampled in nearshore marine eelgrass communities and assess the relationship between these ecological communities and the degree of urbanization in the surrounding watershed. Counter to conventional wisdom, we find strongly increasing richness and decreasing beta diversity with greater urbanization, and similar trends in the diversity of life histories with urbanization. We also find evidence that urbanization influences nearshore communities at local (hundreds of meters) rather than regional (tens of km) scales. Given that different survey methods sample different components of an ecosystem, we then discuss the advantages of eDNA-which we use here to detect hundreds of taxa simultaneously-as a complement to traditional ecological sampling, particularly in the context of broad ecological assessments where exhaustive manual sampling is impractical. Genetic data are a powerful means of uncovering human-ecosystem interactions that might otherwise remain hidden; nevertheless, no sampling method reveals the whole of a biological community.

Directional connectivity in hydrology and ecology

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Larsen, Laurel G.; Choi, Jungyill; Nungesser, Martha K.; Harvey, Judson W.

2012-01-01

Quantifying hydrologic and ecological connectivity has contributed to understanding transport and dispersal processes and assessing ecosystem degradation or restoration potential. However, there has been little synthesis across disciplines. The growing field of ecohydrology and recent recognition that loss of hydrologic connectivity is leading to a global decline in biodiversity underscore the need for a unified connectivity concept. One outstanding need is a way to quantify directional connectivity that is consistent, robust to variations in sampling, and transferable across scales or environmental settings. Understanding connectivity in a particular direction (e.g., streamwise, along or across gradient, between sources and sinks, along cardinal directions) provides critical information for predicting contaminant transport, planning conservation corridor design, and understanding how landscapes or hydroscapes respond to directional forces like wind or water flow. Here we synthesize progress on quantifying connectivity and develop a new strategy for evaluating directional connectivity that benefits from use of graph theory in ecology and percolation theory in hydrology. The directional connectivity index (DCI) is a graph-theory based, multiscale metric that is generalizable to a range of different structural and functional connectivity applications. It exhibits minimal sensitivity to image rotation or resolution within a given range and responds intuitively to progressive, unidirectional change. Further, it is linearly related to the integral connectivity scale length—a metric common in hydrology that correlates well with actual fluxes—but is less computationally challenging and more readily comparable across different landscapes. Connectivity-orientation curves (i.e., directional connectivity computed over a range of headings) provide a quantitative, information-dense representation of environmental structure that can be used for comparison or detection of

Directional connectivity in hydrology and ecology.

Science.gov (United States)

Larsen, Laurel G; Choi, Jungyill; Nungesser, Martha K; Harvey, Judson W

2012-12-01

Quantifying hydrologic and ecological connectivity has contributed to understanding transport and dispersal processes and assessing ecosystem degradation or restoration potential. However, there has been little synthesis across disciplines. The growing field of ecohydrology and recent recognition that loss of hydrologic connectivity is leading to a global decline in biodiversity underscore the need for a unified connectivity concept. One outstanding need is a way to quantify directional connectivity that is consistent, robust to variations in sampling, and transferable across scales or environmental settings. Understanding connectivity in a particular direction (e.g., streamwise, along or across gradient, between sources and sinks, along cardinal directions) provides critical information for predicting contaminant transport, planning conservation corridor design, and understanding how landscapes or hydroscapes respond to directional forces like wind or water flow. Here we synthesize progress on quantifying connectivity and develop a new strategy for evaluating directional connectivity that benefits from use of graph theory in ecology and percolation theory in hydrology. The directional connectivity index (DCI) is a graph-theory based, multiscale metric that is generalizable to a range of different structural and functional connectivity applications. It exhibits minimal sensitivity to image rotation or resolution within a given range and responds intuitively to progressive, unidirectional change. Further, it is linearly related to the integral connectivity scale length--a metric common in hydrology that correlates well with actual fluxes--but is less computationally challenging and more readily comparable across different landscapes. Connectivity-orientation curves (i.e., directional connectivity computed over a range of headings) provide a quantitative, information-dense representation of environmental structure that can be used for comparison or detection of

Do seedling functional groups reflect ecological strategies of woody plant species in Caatinga?

Directory of Open Access Journals (Sweden)

Tatiane Gomes Calaça Menezes

2017-11-01

Full Text Available ABSTRACT It is assumed that morphological traits of seedlings reflect different strategies in response to environmental conditions. The ecological significance of this has been widely documented in rainforests, where habitat structure and species interactions play an important role in community assembly. However, in seasonally dry ecosystems, where environmental filtering is expected to strongly influence community structure, this relationship is poorly understood. We investigated this relationship between functional groups of seedlings and life history traits and tested whether functional group predicts the ecological strategies employed by woody species to deal with the stressful conditions in seasonally dry ecosystems. Seedling functional groups, life history traits and traits that reflect ecological strategies for occupying seasonally dry environments were described for twenty-six plant species. Seedlings of species from the Caatinga vegetation exhibited a functional profile different from that observed in rainforests ecosystems. Phanerocotylar-epigeal seedlings were the most frequently observed groups, and had the largest range of ecological strategies related to dealing with seasonally dry environments, while phanerocotylar-hypogeal-reserve seedlings exhibited an increase in frequency with seasonality. We discuss these results in relation to those observed in other tropical forests and their ecological significance in seasonally dry environments.

Why should we investigate the morphological disparity of plant clades?

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Oyston, Jack W; Hughes, Martin; Gerber, Sylvain; Wills, Matthew A

2016-04-01

Disparity refers to the morphological variation in a sample of taxa, and is distinct from diversity or taxonomic richness. Diversity and disparity are fundamentally decoupled; many groups attain high levels of disparity early in their evolution, while diversity is still comparatively low. Diversity may subsequently increase even in the face of static or declining disparity by increasingly fine sub-division of morphological 'design' space (morphospace). Many animal clades reached high levels of disparity early in their evolution, but there have been few comparable studies of plant clades, despite their profound ecological and evolutionary importance. This study offers a prospective and some preliminary macroevolutionary analyses. Classical morphometric methods are most suitable when there is reasonable conservation of form, but lose traction where morphological differences become greater (e.g. in comparisons across higher taxa). Discrete character matrices offer one means to compare a greater diversity of forms. This study explores morphospaces derived from eight discrete data sets for major plant clades, and discusses their macroevolutionary implications. Most of the plant clades in this study show initial, high levels of disparity that approach or attain the maximum levels reached subsequently. These plant clades are characterized by an initial phase of evolution during which most regions of their empirical morphospaces are colonized. Angiosperms, palms, pines and ferns show remarkably little variation in disparity through time. Conifers furnish the most marked exception, appearing at relatively low disparity in the latest Carboniferous, before expanding incrementally with the radiation of successive, tightly clustered constituent sub-clades. Many cladistic data sets can be repurposed for investigating the morphological disparity of plant clades through time, and offer insights that are complementary to more focused morphometric studies. The unique structural and

Dynamic expression of ancient and novel molluscan shell genes during ecological transitions

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Wörheide Gert

2007-09-01

Full Text Available Abstract Background The Mollusca constitute one of the most morphologically and ecologically diverse metazoan phyla, occupying a wide range of marine, terrestrial and freshwater habitats. The evolutionary success of the molluscs can in part be attributed to the evolvability of the external shell. Typically, the shell first forms during embryonic and larval development, changing dramatically in shape, colour and mineralogical composition as development and maturation proceeds. Major developmental transitions in shell morphology often correlate with ecological transitions (e.g. from a planktonic to benthic existence at metamorphosis. While the genes involved in molluscan biomineralisation are beginning to be identified, there is little understanding of how these are developmentally regulated, or if the same genes are operational at different stages of the mollusc's life. Results Here we relate the developmental expression of nine genes in the tissue responsible for shell production – the mantle – to ecological transitions that occur during the lifetime of the tropical abalone Haliotis asinina (Vetigastropoda. Four of these genes encode evolutionarily ancient proteins, while four others encode secreted proteins with little or no identity to known proteins. Another gene has been previously described from the mantle of another haliotid vetigastropod. All nine genes display dynamic spatial and temporal expression profiles within the larval shell field and juvenile mantle. Conclusion These expression data reflect the regulatory complexity that underlies molluscan shell construction from larval stages to adulthood, and serves to highlight the different ecological demands placed on each stage. The use of both ancient and novel genes in all stages of shell construction also suggest that a core set of shell-making genes was provided by a shared metazoan ancestor, which has been elaborated upon to produce the range of molluscan shell types we see today.

Identifying Social-ecological Linkages to Develop a Community Fire Plan in Mexico

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Rachel A.S Sheridan

2015-01-01

Full Text Available Community forestry in rural Mexico presents a unique opportunity to study the linkages and feedback within coupled social-ecological systems due to the fact that agrarian or indigenous communities control approximately half of the national territory of Mexico. We used social and ecological diagnostic tools to develop a fire management strategy for a communal forest containing an endemic piñón pine species, Pinus cembroides subs. orizabensis, in the state of Tlaxcala, Mexico. The ecological diagnostic was done through fuel inventory, forest structure sampling, and fire behaviour modelling. The social assessment was conducted through household interviews, community workshops, and direct participant observation. The ecological fire hazard was quantified and coupled with the social assessment to develop a fire management plan. Vertical fuel continuity and flashy surface fuels created a high fire hazard. Modelled fire behaviour showed a rapid rate of spread and high flame lengths under multiple scenarios. Relative impunity for starting forest fires, poor community and inter-agency organisation, and lack of project continuity across organisational sectors appear to be the most significant social limiting factors for wildfire management. Combining both social and ecological diagnostic tools provides a comprehensive understanding of the actual risks to forests, and identifies realistic community-supported options for conservation on cooperatively managed lands.

Spatial structure of morphological and neutral genetic variation in Brook Trout

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Kazyak, David C.; Hilderbrand, Robert H.; Keller, Stephen R.; Colaw, Mark C.; Holloway, Amanda E.; Morgan, Raymond P.; King, Timothy L.

2015-01-01

Brook Trout Salvelinus fontinalis exhibit exceptional levels of life history variation, remarkable genetic variability, and fine-scale population structure. In many cases, neighboring populations may be highly differentiated from one another to an extent that is comparable with species-level distinctions in other taxa. Although genetic samples have been collected from hundreds of populations and tens of thousands of individuals, little is known about whether differentiation at neutral markers reflects phenotypic differences among Brook Trout populations. We compared differentiation in morphology and neutral molecular markers among populations from four geographically proximate locations (all within 24 km) to examine how genetic diversity covaries with morphology. We found significant differences among and/or within streams for all three morphological axes examined and identified the source stream of many individuals based on morphology (52.3% classification efficiency). Although molecular and morphological differentiation among streams ranged considerably (mean pairwise FST: 0.023–0.264; pairwise PST: 0.000–0.339), the two measures were not significantly correlated. While in some cases morphological characters appear to have diverged to a greater extent than expected by neutral genetic drift, many traits were conserved to a greater extent than were neutral genetic markers. Thus, while Brook Trout exhibit fine-scale spatial patterns in both morphology and neutral genetic diversity, these types of biological variabilities are being structured by different ecological and evolutionary processes. The relative influences of genetic drift versus selection and phenotypic plasticity in shaping morphology appear to vary among populations occupying nearby streams.

Validated methodology for quantifying infestation levels of dreissenid mussels in environmental DNA (eDNA) samples

OpenAIRE

Peñarrubia Lozano, Luis; Alcaraz Cazorla, Carles; Vaate, Abraham bij de; Sanz Ball-llosera, Núria; Pla Zanuy, Carles; Vidal Fàbrega, Oriol; Viñas de Puig, Jordi

2016-01-01

The zebra mussel (Dreissena polymorpha Pallas, 1771) and the quagga mussel (D. rostriformis Deshayes, 1838) are successful invasive bivalves with substantial ecological and economic impacts in freshwater systems once they become established. Since their eradication is extremely difficult, their detection at an early stage is crucial to prevent spread. In this study, we optimized and validated a qPCR detection method based on the histone H2B gene to quantify combined infestation levels of zebr...

A quantitative spatiotemporal analysis of microglia morphology during ischemic stroke and reperfusion

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Morrison Helena W

2013-01-01

Full Text Available Abstract Background Microglia cells continuously survey the healthy brain in a ramified morphology and, in response to injury, undergo progressive morphological and functional changes that encompass microglia activation. Although ideally positioned for immediate response to ischemic stroke (IS and reperfusion, their progressive morphological transformation into activated cells has not been quantified. In addition, it is not well understood if diverse microglia morphologies correlate to diverse microglia functions. As such, the dichotomous nature of these cells continues to confound our understanding of microglia-mediated injury after IS and reperfusion. The purpose of this study was to quantitatively characterize the spatiotemporal pattern of microglia morphology during the evolution of cerebral injury after IS and reperfusion. Methods Male C57Bl/6 mice were subjected to focal cerebral ischemia and periods of reperfusion (0, 8 and 24 h. The microglia process length/cell and number of endpoints/cell was quantified from immunofluorescent confocal images of brain regions using a skeleton analysis method developed for this study. Live cell morphology and process activity were measured from movies acquired in acute brain slices from GFP-CX3CR1 transgenic mice after IS and 24-h reperfusion. Regional CD11b and iNOS expressions were measured from confocal images and Western blot, respectively, to assess microglia proinflammatory function. Results Quantitative analysis reveals a significant spatiotemporal relationship between microglia morphology and evolving cerebral injury in the ipsilateral hemisphere after IS and reperfusion. Microglia were both hyper- and de-ramified in striatal and cortical brain regions (respectively after 60 min of focal cerebral ischemia. However, a de-ramified morphology was prominent when ischemia was coupled to reperfusion. Live microglia were de-ramified, and, in addition, process activity was severely blunted proximal to

Can terrestrial diversity be predicted from soil morphology?

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Fournier, Bertrand; Guenat, Claire; Mitchell, Edward

2010-05-01

Restoration ecology is a young discipline and, as a consequence, many concepts and methods are not yet mature. A good example of this is the case of floodplains which have been intensively embanked, dammed or otherwise engineered in industrialized countries, but are now increasingly being restored, often at high cost. There is however much confusion over the goals of floodplain restoration projects and the methods, criteria, and indicators to assess their success. Nature practitioners are interested in knowing how many and which variables are needed for an efficient monitoring and/or assessment. Although many restoration success assessment methods have been developed to meet this need, most indicators currently used are complicated and expensive or provide only spatially or temporally limited information on these complex systems. Perhaps as a result, no standard method has yet been defined and post-restoration monitoring is not systematically done. Optimizing indicators would help improve the credibility of restoration projects and would thus help to convince stakeholders and managers to support monitoring programs. As a result, defining the predictive power of restoration success indicators, as well as selecting the most pertinent variables among the ones currently used is of major importance for a sustainable and adaptive management of our river ecosystems. Soil characteristics determine key functions (e.g. decomposition) and ecosystem structure (e.g. vegetation) in terrestrial ecosystems. They therefore have a high potential information value that is, however, generally not considered in floodplain restoration assessment. In order to explore this potential, we recently developed a new synthetic indicator based on soil morphology for the evaluation of river restoration success. Following Hutchinson's ecological niche concept, we hypothesised that terrestrial biodiversity can be predicted based on soil characteristics, but that these characteristics do not perform

PCB Food Web Dynamics Quantify Nutrient and Energy Flow in Aquatic Ecosystems.

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McLeod, Anne M; Paterson, Gordon; Drouillard, Ken G; Haffner, G Douglas

2015-11-03

Measuring in situ nutrient and energy flows in spatially and temporally complex aquatic ecosystems represents a major ecological challenge. Food web structure, energy and nutrient budgets are difficult to measure, and it is becoming more important to quantify both energy and nutrient flow to determine how food web processes and structure are being modified by multiple stressors. We propose that polychlorinated biphenyl (PCB) congeners represent an ideal tracer to quantify in situ energy and nutrient flow between trophic levels. Here, we demonstrate how an understanding of PCB congener bioaccumulation dynamics provides multiple direct measurements of energy and nutrient flow in aquatic food webs. To demonstrate this novel approach, we quantified nitrogen (N), phosphorus (P) and caloric turnover rates for Lake Huron lake trout, and reveal how these processes are regulated by both growth rate and fish life history. Although minimal nutrient recycling was observed in young growing fish, slow growing, older lake trout (>5 yr) recycled an average of 482 Tonnes·yr(-1) of N, 45 Tonnes·yr(-1) of P and assimilated 22 TJ yr(-1) of energy. Compared to total P loading rates of 590 Tonnes·yr(-1), the recycling of primarily bioavailable nutrients by fish plays an important role regulating the nutrient states of oligotrophic lakes.

Morphology Dependent Assessment of Resilience for Urban Areas

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Kai Fischer

2018-05-01

Full Text Available The formation of new threats and the increasing complexity of urban built infrastructures underline the need for more robust and sustainable systems, which are able to cope with adverse events. Achieving sustainability requires the strengthening of resilience. Currently, a comprehensive approach for the quantification of resilience of urban infrastructure is missing. Within this paper, a new generalized mathematical framework is presented. A clear definition of terms and their interaction builds the basis of this resilience assessment scheme. Classical risk-based as well as additional components are aligned along the timeline before, during and after disruptive events, to quantify the susceptibility, the vulnerability and the response and recovery behavior of complex systems for multiple threat scenarios. The approach allows the evaluation of complete urban surroundings and enables a quantitative comparison with other development plans or cities. A comprehensive resilience framework should cover at least preparation, prevention, protection, response and recovery. The presented approach determines respective indicators and provides decision support, which enhancement measures are more effective. Hence, the framework quantifies for instance, if it is better to avoid a hazardous event or to tolerate an event with an increased robustness. An application example is given to assess different urban forms, i.e., morphologies, with consideration of multiple adverse events, like terrorist attacks or earthquakes, and multiple buildings. Each urban object includes a certain number of attributes, like the object use, the construction type, the time-dependent number of persons and the value, to derive different performance targets. The assessment results in the identification of weak spots with respect to single resilience indicators. Based on the generalized mathematical formulation and suitable combination of indicators, this approach can quantify the

Species delimitation and evolution in morphologically and chemically diverse communities of the lichen-forming genus Xanthoparmelia (Parmeliaceae, Ascomycota) in western North America.

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Leavitt, Steven D; Johnson, Leigh; St Clair, Larry L

2011-02-01

Accurate species delimitation is important for understanding the diversification of biota and has critical implications for ecological and conservation studies. However, a growing body of evidence indicates that morphology-based species circumspection in lichenized fungi misrepresents fungal diversity. The foliose lichen genus Xanthoparmelia includes over 800 species displaying a complex array of morphological and secondary metabolite diversity. We used a multifaceted approach, applying phylogenetic, population genetic, and genealogical analyses to delimit species in a single well-supported monophyletic clade containing 10 morphologically and chemically diverse Xanthoparmelia species in western North America. Sequence data from four ribosomal and two low-copy, protein-coding markers, along with chemical and morphological data were used to assess species diversity. We found that traditionally circumscribed species are not supported by molecular data. Rather, all sampled taxa were better represented by three polymorphic population clusters. Our results suggest that secondary metabolite variation may have limited utility in diagnosing lineages within this group, while identified populations clusters did not reflect major phylogeographic or ecological patterns. In contrast to studies revealing previously undiscovered fungal lineages masked within lichen species circumscribed by traditional morphological and chemical concepts, the present study suggests that species diversity has been overestimated in the species-rich genus Xanthoparmelia.

Landscape metrics application in ecological and visual landscape assessment

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Gavrilović Suzana

2017-01-01

Full Text Available The development of landscape-ecological approach application in spatial planning provides exact theoretical and empirical evidence for monitoring ecological consequences of natural and/or anthropogenic factors, particularly changes in spatial structures caused by them. Landscape pattern which feature diverse landscape values is the holder of the unique landscape character at different spatial levels and represents a perceptual domain for its users. Using the landscape metrics, the parameters of landscape composition and configuration are mathematical algorithms that quantify the specific spatial characteristics used for interpretation of landscape features and processes (physical and ecological aspect, as well as forms (visual aspect and the meaning (cognitive aspect of the landscape. Landscape metrics has been applied mostly in the ecological and biodiversity assessments as well as in the determination of the level of structural change of landscape, but more and more applied in the assessment of the visual character of the landscape. Based on a review of relevant literature, the aim of this work is to show the main trends of landscape metrics within the aspect of ecological and visual assessments. The research methodology is based on the analysis, classification and systematization of the research studies published from 2000 to 2016, where the landscape metrics is applied: (1 the analysis of landscape pattern and its changes, (2 the analysis of biodiversity and habitat function and (3 a visual landscape assessment. By selecting representative metric parameters for the landscape composition and configuration, for each category is formed the basis for further landscape metrics research and application for the integrated ecological and visual assessment of the landscape values. Contemporary conceptualization of the landscape is seen holistically, and the future research should be directed towards the development of integrated landscape assessment

Accounting for uncertainty in ecological analysis: the strengths and limitations of hierarchical statistical modeling.

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Cressie, Noel; Calder, Catherine A; Clark, James S; Ver Hoef, Jay M; Wikle, Christopher K

2009-04-01

Analyses of ecological data should account for the uncertainty in the process(es) that generated the data. However, accounting for these uncertainties is a difficult task, since ecology is known for its complexity. Measurement and/or process errors are often the only sources of uncertainty modeled when addressing complex ecological problems, yet analyses should also account for uncertainty in sampling design, in model specification, in parameters governing the specified model, and in initial and boundary conditions. Only then can we be confident in the scientific inferences and forecasts made from an analysis. Probability and statistics provide a framework that accounts for multiple sources of uncertainty. Given the complexities of ecological studies, the hierarchical statistical model is an invaluable tool. This approach is not new in ecology, and there are many examples (both Bayesian and non-Bayesian) in the literature illustrating the benefits of this approach. In this article, we provide a baseline for concepts, notation, and methods, from which discussion on hierarchical statistical modeling in ecology can proceed. We have also planted some seeds for discussion and tried to show where the practical difficulties lie. Our thesis is that hierarchical statistical modeling is a powerful way of approaching ecological analysis in the presence of inevitable but quantifiable uncertainties, even if practical issues sometimes require pragmatic compromises.

Potentials and limitations of adaptive plasticity in filtering screen morphology of Daphnia (Crustacea: Cladocera)

Czech Academy of Sciences Publication Activity Database

Macháček, Jiří; Seďa, Jaromír

2016-01-01

Roč. 38, č. 5 (2016), s. 1269-1280 ISSN 0142-7873 R&D Projects: GA ČR(CZ) GA206/09/1325; GA ČR(CZ) GA15-24309S Institutional support: RVO:60077344 Keywords : Daphnia * filtering screen morphology * transgenerational plasticity * ontogenetic plasticity * taxonspecific trait Subject RIV: EH - Ecology, Behaviour Impact factor: 1.983, year: 2016

Collective movement in ecology: from emerging technologies to conservation and management.

Science.gov (United States)

Westley, Peter A H; Berdahl, Andrew M; Torney, Colin J; Biro, Dora

2018-05-19

Recent advances in technology and quantitative methods have led to the emergence of a new field of study that stands to link insights of researchers from two closely related, but often disconnected disciplines: movement ecology and collective animal behaviour. To date, the field of movement ecology has focused on elucidating the internal and external drivers of animal movement and the influence of movement on broader ecological processes. Typically, tracking and/or remote sensing technology is employed to study individual animals in natural conditions. By contrast, the field of collective behaviour has quantified the significant role social interactions play in the decision-making of animals within groups and, to date, has predominantly relied on controlled laboratory-based studies and theoretical models owing to the constraints of studying interacting animals in the field. This themed issue is intended to formalize the burgeoning field of collective movement ecology which integrates research from both movement ecology and collective behaviour. In this introductory paper, we set the stage for the issue by briefly examining the approaches and current status of research in these areas. Next, we outline the structure of the theme issue and describe the obstacles collective movement researchers face, from data acquisition in the field to analysis and problems of scale, and highlight the key contributions of the assembled papers. We finish by presenting research that links individual and broad-scale ecological and evolutionary processes to collective movement, and finally relate these concepts to emerging challenges for the management and conservation of animals on the move in a world that is increasingly impacted by human activity.This article is part of the theme issue 'Collective movement ecology'. © 2018 The Author(s).

Bayesian Spatiotemporal Analysis of Socio-Ecologic Drivers of Ross River Virus Transmission in Queensland, Australia

Science.gov (United States)

Hu, Wenbiao; Clements, Archie; Williams, Gail; Tong, Shilu; Mengersen, Kerrie

2010-01-01

This study aims to examine the impact of socio-ecologic factors on the transmission of Ross River virus (RRV) infection and to identify areas prone to social and ecologic-driven epidemics in Queensland, Australia. We used a Bayesian spatiotemporal conditional autoregressive model to quantify the relationship between monthly variation of RRV incidence and socio-ecologic factors and to determine spatiotemporal patterns. Our results show that the average increase in monthly RRV incidence was 2.4% (95% credible interval (CrI): 0.1–4.5%) and 2.0% (95% CrI: 1.6–2.3%) for a 1°C increase in monthly average maximum temperature and a 10 mm increase in monthly average rainfall, respectively. A significant spatiotemporal variation and interactive effect between temperature and rainfall on RRV incidence were found. No association between Socio-economic Index for Areas (SEIFA) and RRV was observed. The transmission of RRV in Queensland, Australia appeared to be primarily driven by ecologic variables rather than social factors. PMID:20810846

Quantifiers and working memory

NARCIS (Netherlands)

Szymanik, J.; Zajenkowski, M.

2010-01-01

The paper presents a study examining the role of working memory in quantifier verification. We created situations similar to the span task to compare numerical quantifiers of low and high rank, parity quantifiers and proportional quantifiers. The results enrich and support the data obtained

Quantifiers and working memory

NARCIS (Netherlands)

Szymanik, J.; Zajenkowski, M.

2009-01-01

The paper presents a study examining the role of working memory in quantifier verification. We created situations similar to the span task to compare numerical quantifiers of low and high rank, parity quantifiers and proportional quantifiers. The results enrich and support the data obtained

Relationship between foveal cone specialization and pit morphology in albinism.

Science.gov (United States)

Wilk, Melissa A; McAllister, John T; Cooper, Robert F; Dubis, Adam M; Patitucci, Teresa N; Summerfelt, Phyllis; Anderson, Jennifer L; Stepien, Kimberly E; Costakos, Deborah M; Connor, Thomas B; Wirostko, William J; Chiang, Pei-Wen; Dubra, Alfredo; Curcio, Christine A; Brilliant, Murray H; Summers, C Gail; Carroll, Joseph

2014-05-20

Albinism is associated with disrupted foveal development, though intersubject variability is becoming appreciated. We sought to quantify this variability, and examine the relationship between foveal cone specialization and pit morphology in patients with a clinical diagnosis of albinism. We recruited 32 subjects with a clinical diagnosis of albinism. DNA was obtained from 25 subjects, and known albinism genes were analyzed for mutations. Relative inner and outer segment (IS and OS) lengthening (fovea-to-perifovea ratio) was determined from manually segmented spectral domain-optical coherence tomography (SD-OCT) B-scans. Foveal pit morphology was quantified for eight subjects from macular SD-OCT volumes. Ten subjects underwent imaging with adaptive optics scanning light ophthalmoscopy (AOSLO), and cone density was measured. We found mutations in 22 of 25 subjects, including five novel mutations. All subjects lacked complete excavation of inner retinal layers at the fovea, though four subjects had foveal pits with normal diameter and/or volume. Peak cone density and OS lengthening were variable and overlapped with that observed in normal controls. A fifth hyper-reflective band was observed in the outer retina on SD-OCT in the majority of the subjects with albinism. Foveal cone specialization and pit morphology vary greatly in albinism. Normal cone packing was observed in the absence of a foveal pit, suggesting a pit is not required for packing to occur. The degree to which retinal anatomy correlates with genotype or visual function remains unclear, and future examination of larger patient groups will provide important insight on this issue. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

GEOGRAPHIC AND ECOLOGICAL AMPLITUDE IN THE NECTARIVOROUS BAT ANOURA FISTULATA (PYHLLOSTOMIDAE: GLOSSOPHAGINAE

Directory of Open Access Journals (Sweden)

HUGO MANTILLA-MELUK

2014-12-01

Full Text Available The wide range of feeding habits among phyllostomid bats has resulted in the selection of unique and contrasting morphological attributes. It has been suggested that nectarivorous bat species co-evolve with the plants they use as primary source of food, and changes in morphology and behavior in the bat, are in some way directed by changes in morphology and phenological cycles of the plants. The nectarivorous bat Anoura fistulata (Pyhllostomidae: Glossophaginae has the longest tongue in proportion to body size among mammals; feature that apparently allows the species to take nectar from flowers with long corollas, some of them typical of highland ecosystems. In spite of this unique morphological adaptation, little is known on the ecological requirements of the species. Herein, Geographic Information System-based analyses and niche modeling techniques were applied to investigate the geographic and ecological niche breath of A. fistulata. We also introduce the first Bolivian record of the species collected at Hernando Siles, Department of Chuquisaca (20°10’0.0’’ S, 64°15’0.00’’ W, at 1,524 m, which represents a remarkable extension in the distribution of the species of more than 7°. Our analyses revealed that A. fistulata occurs in contrasting ecosystems, from Andean montane and pre-montane moist forest in Western Ecuador and Central Colombia, up to arid and semiarid environments in southern Colombia and Bolivia . Anoura fistulata occurs across a wide elevational range between 1,175 and 2,510 m, which is well represented along the geologic unit of the Batholith of Ecuador. A constriction of this elevational belt along the Peruvian Punas and Yungas was suggested as a natural barrier for the establishment of A. fistulata. The Peruvian Punas and Yungas isolate A. fistulata of Bolivia from records in the northern range of the distribution of the species.

A neural-fuzzy approach to classify the ecological status in surface waters

International Nuclear Information System (INIS)

Ocampo-Duque, William; Schuhmacher, Marta; Domingo, Jose L.

2007-01-01

A methodology based on a hybrid approach that combines fuzzy inference systems and artificial neural networks has been used to classify ecological status in surface waters. This methodology has been proposed to deal efficiently with the non-linearity and highly subjective nature of variables involved in this serious problem. Ecological status has been assessed with biological, hydro-morphological, and physicochemical indicators. A data set collected from 378 sampling sites in the Ebro river basin has been used to train and validate the hybrid model. Up to 97.6% of sampling sites have been correctly classified with neural-fuzzy models. Such performance resulted very competitive when compared with other classification algorithms. With non-parametric classification-regression trees and probabilistic neural networks, the predictive capacities were 90.7% and 97.0%, respectively. The proposed methodology can support decision-makers in evaluation and classification of ecological status, as required by the EU Water Framework Directive. - Fuzzy inference systems can be used as environmental classifiers

New Insights on the Morphology of Adult Mouse Penis1

Science.gov (United States)

Rodriguez, Esequiel; Weiss, Dana A.; Yang, Jennifer H.; Menshenina, Julia; Ferretti, Max; Cunha, Tristan J.; Barcellos, Dale; Chan, Lok Yun; Risbridger, Gail; Cunha, Gerald R.; Baskin, Laurence S.

2011-01-01

ABSTRACT The adult mouse penis represents the end point of masculine sex differentiation of the embryonic genital tubercle and contains bone, cartilage, the urethra, erectile bodies, several types of epithelium, and many individual cell types arrayed into specific anatomical structures. Using contemporary high-resolution imaging techniques, we sought to provide new insights to the current description of adult mouse penile morphology to enable understanding of penile abnormalities, including hypospadias. Examination of serial transverse and longitudinal sections, scanning electron microscopy, and three-dimensional (3D) reconstruction provided a new appreciation of the individual structures in the adult mouse penis and their 3D interrelationships. In so doing, we discovered novel paired erectile bodies, the male urogenital mating protuberance (MUMP), and more accurately described the urethral meatus. These morphological observations were quantified by morphometric analysis and now provide accurate morphological end points of sex differentiation of mouse penis that will be the foundation of future studies to identify normal and abnormal penile development. PMID:21918128

Notes on the Reproductive Ecology and Description of the Preimaginal Morphology of Elaphrus sugai Nakane, the Most Endangered Species of Elaphrus Fabricius (Coleoptera: Carabidae Ground Beetle Worldwide.

Directory of Open Access Journals (Sweden)

Kôji Sasakawa

Full Text Available Elucidating the basic life-history of endangered species is the first important step in the conservation of such species. This study examined the reproductive ecology and the preimaginal morphology of the endangered ground beetle Elaphrus sugai Nakane (Coleoptera: Carabidae; currently, the Watarase wetland of the central Kanto Plain, Japan is the only confirmed locality of this beetle species. Laboratory rearing of reproductive adults collected in early April revealed that females can lay more than 131 eggs. Eggs were laid in mud, without an egg chamber. Larvae reached adulthood when fed a diet of mealworms, indicating that E. sugai larvae are insect larvae feeders. An earthworm diet, the optimal diet for larvae of a congeneric species (E. punctatus Motschulsky, was lethal to E. sugai larvae. The egg stage was 3-4 days in duration under a 16L8D cycle (22°C. The duration from hatching to adult eclosion was 23-42 days at various temperatures simulating those of the reproductive period. Larval morphology was similar to that of consubgeneric species described previously. The pupa is unusual, in that the setae on the abdominal tergites are long (twice as long as those of the abdominal segment and have somewhat "coiled" apices. Finally, the current endangered status of E. sugai was compared to that of E. viridis Horn, which has been regarded as the most endangered species of the genus worldwide.

The relevance of morphology for habitat use and locomotion in two species of wall lizards

Science.gov (United States)

Gomes, Verónica; Carretero, Miguel A.; Kaliontzopoulou, Antigoni

2016-01-01

Understanding if morphological differences between organisms that occupy different environments are associated to differences in functional performance can suggest a functional link between environmental and morphological variation. In this study we examined three components of the ecomorphological paradigm - morphology, locomotor performance and habitat use - using two syntopic wall lizards endemic to the Iberian Peninsula as a case study to establish whether morphological variation is associated with habitat use and determine the potential relevance of locomotor performance for such an association. Differences in habitat use between both lizards matched patterns of morphological variation. Indeed, individuals of Podarcis guadarramae lusitanicus, which are more flattened, used more rocky environments, whereas Podarcis bocagei, which have higher heads, used more vegetation than rocks. These patterns translated into a significant association between morphology and habitat use. Nevertheless, the two species were only differentiated in some of the functional traits quantified, and locomotor performance did not exhibit an association with morphological traits. Our results suggest that the link between morphology and habitat use is mediated by refuge use, rather than locomotor performance, in this system, and advise caution when extrapolating morphology-performance-environment associations across organisms.

Indigenous Ecological Knowledge and Modern Western Ecological ...

African Journals Online (AJOL)

Indigenous knowledge is often dismissed as 'traditional and outdated', and hence irrelevant to modern ecological assessment. This theoretical paper critically examines the arguments advanced to elevate modern western ecological knowledge over indigenous ecological knowledge, as well as the sources and uses of ...

Forensic Entomology: Evaluating Uncertainty Associated With Postmortem Interval (PMI) Estimates With Ecological Models.

Science.gov (United States)

Faris, A M; Wang, H-H; Tarone, A M; Grant, W E

2016-05-31

Estimates of insect age can be informative in death investigations and, when certain assumptions are met, can be useful for estimating the postmortem interval (PMI). Currently, the accuracy and precision of PMI estimates is unknown, as error can arise from sources of variation such as measurement error, environmental variation, or genetic variation. Ecological models are an abstract, mathematical representation of an ecological system that can make predictions about the dynamics of the real system. To quantify the variation associated with the pre-appearance interval (PAI), we developed an ecological model that simulates the colonization of vertebrate remains by Cochliomyia macellaria (Fabricius) (Diptera: Calliphoridae), a primary colonizer in the southern United States. The model is based on a development data set derived from a local population and represents the uncertainty in local temperature variability to address PMI estimates at local sites. After a PMI estimate is calculated for each individual, the model calculates the maximum, minimum, and mean PMI, as well as the range and standard deviation for stadia collected. The model framework presented here is one manner by which errors in PMI estimates can be addressed in court when no empirical data are available for the parameter of interest. We show that PAI is a potential important source of error and that an ecological model is one way to evaluate its impact. Such models can be re-parameterized with any development data set, PAI function, temperature regime, assumption of interest, etc., to estimate PMI and quantify uncertainty that arises from specific prediction systems. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

BMD PREDICTION OF DEATH IS ENCAPSULATED BY THE MORPHOLOGICAL ATHEROSCLEROSIS CALCIFICATION DISTRIBUTION (MACD) INDEX

DEFF Research Database (Denmark)

Ganz, Melanie; Nielsen, Mads; Karsdal, Morten

2009-01-01

.3±0.3 years and of which CVD, cancer, and all cause deaths were recorded. The spine BMD and aortic calcification markers, AC24 and the recently proposed Morphological Atherosclerosis Calcification Distribution (MACD) index, were quantified from DXA scans and lateral X-rays respectively. The MACD...

Insights into Penicillium roqueforti Morphological and Genetic Diversity

Science.gov (United States)

Gillot, Guillaume; Jany, Jean-Luc; Coton, Monika; Le Floch, Gaétan; Debaets, Stella; Ropars, Jeanne; López-Villavicencio, Manuela; Dupont, Joëlle; Branca, Antoine; Giraud, Tatiana; Coton, Emmanuel

2015-01-01

Fungi exhibit substantial morphological and genetic diversity, often associated with cryptic species differing in ecological niches. Penicillium roqueforti is used as a starter culture for blue-veined cheeses, being responsible for their flavor and color, but is also a common spoilage organism in various foods. Different types of blue-veined cheeses are manufactured and consumed worldwide, displaying specific organoleptic properties. These features may be due to the different manufacturing methods and/or to the specific P. roqueforti strains used. Substantial morphological diversity exists within P. roqueforti and, although not taxonomically valid, several technological names have been used for strains on different cheeses (e.g., P. gorgonzolae, P. stilton). A worldwide P. roqueforti collection from 120 individual blue-veined cheeses and 21 other substrates was analyzed here to determine (i) whether P. roqueforti is a complex of cryptic species, by applying the Genealogical Concordance Phylogenetic Species Recognition criterion (GC-PSR), (ii) whether the population structure assessed using microsatellite markers correspond to blue cheese types, and (iii) whether the genetic clusters display different morphologies. GC-PSR multi-locus sequence analyses showed no evidence of cryptic species. The population structure analysis using microsatellites revealed the existence of highly differentiated populations, corresponding to blue cheese types and with contrasted morphologies. This suggests that the population structure has been shaped by different cheese-making processes or that different populations were recruited for different cheese types. Cheese-making fungi thus constitute good models for studying fungal diversification under recent selection. PMID:26091176

Nematode-associated microbial taxa do not correlate with host phylogeny, geographic region or feeding morphology in marine sediment habitats.

Science.gov (United States)

Schuelke, Taruna; Pereira, Tiago José; Hardy, Sarah M; Bik, Holly M

2018-04-01

Studies of host-associated microbes are critical for advancing our understanding of ecology and evolution across diverse taxa and ecosystems. Nematode worms are ubiquitous across most habitats on earth, yet little is known about host-associated microbial assemblages within the phylum. Free-living nematodes are globally abundant and diverse in marine sediments, with species exhibiting distinct buccal cavity (mouth) morphologies that are thought to play an important role in feeding ecology and life history strategies. Here, we investigated patterns in marine nematode microbiomes, by characterizing host-associated microbial taxa in 281 worms isolated from a range of habitat types (deep-sea, shallow water, methane seeps, Lophelia coral mounds, kelp holdfasts) across three distinct geographic regions (Arctic, Southern California and Gulf of Mexico). Microbiome profiles were generated from single worms spanning 33 distinct morphological genera, using a two-gene metabarcoding approach to amplify the V4 region of the 16S ribosomal RNA (rRNA) gene targeting bacteria/archaea and the V1-V2 region of the 18S rRNA gene targeting microbial eukaryotes. Contrary to our expectations, nematode microbiome profiles demonstrated no distinct patterns either globally (across depths and ocean basins) or locally (within site); prokaryotic and eukaryotic microbial assemblages did not correlate with nematode feeding morphology, host phylogeny or morphological identity, ocean region or marine habitat type. However, fine-scale analysis of nematode microbiomes revealed a variety of novel ecological interactions, including putative parasites and symbionts, and potential associations with bacterial/archaeal taxa involved in nitrogen and methane cycling. Our results suggest that in marine habitats, free-living nematodes may utilize diverse and generalist foraging strategies that are not correlated with host genotype or feeding morphology. Furthermore, some abiotic factors such as geographic region

Linking hydrology, morphodynamics and ecology to assess the restoration potential of the heavily regulated Sarca River, NE Italy

Science.gov (United States)

Carolli, Mauro; Zolezzi, Guido; Pellegrini, Stefano; Gelmini, Francesca; Deriu, Micaela

2017-04-01

We develop an integrated eco-hydro-morphological quantitative investigation of the upper course of the Alpine Sarca River (NE Italy), for the purpose of assessing its potential in terms of environmental restoration. The Sarca River has been subject to heavy exploitation for hydropower production since the 1950s through a complex infrastructural system. As for many regulated Alpine rivers, increasing local interest has recently been developing to design and implement river restoration measures to improve the environmental conditions and ecosystem services that the river can provide. The aim of the work is to develop and apply a quantitative approach for a preliminary assessment of the successful potential of different river restoration options in the light of the recent eco-hydro-morphological dynamics of the Sarca river system at the catchment scale. The proposed analysis consists of three main steps: (1) detection of the main drivers of flow and sediment supply regimes alteration and characterization of such alteration; (2) a quantification of the effects of those alterations on geomorphic processes and fish habitat conditions; (3) the analysis of the restoration potential in the light of the results of the previous assessment. The analysis is tailored to the existing data availability, which is relatively high as for most river systems of comparable size in Europe, but not as much as in the case of a targeted research project, thus providing a representative case for many other regulated river catchments. Hydrological alteration is quantified by comparing recent (20 years) streamflow time series with a reconstructed series of analogous length, using a hydrological model that has been run excluding any man-made water abstraction, release and artificial reservoirs. upstream and downstream a large dam in the middle course of the river. By choosing the adult marble trout as target (endemic) fish species, effects of the alterations on the temporal and spatial habitat

Surface morphology of amygdala is associated with trait anxiety.

Directory of Open Access Journals (Sweden)

Shuyu Li

Full Text Available Previous neuroimaging studies have suggested a role of amygdala in trait anxiety level, in which amygdala was typically treated as a whole. To date, it remains unknown whether the morphology of specific subregions of amygdala are associated with trait anxiety. Here, we employed a shape analysis approach to locate the association between its morphology and trait anxiety on the surface of amygdala. 24 healthy young participants were included. The boundary of amygdala for each subject was first manually outlined using high-resolution magnetic resonance (MR image, followed by 3D surface reconstruction and parameterization using spherical harmonic description. Two point-wise metrics, direct displacement between the individual surface and atlas surface and its normal projection, were used to quantify the surface morphology of amygdala. Statistical analysis revealed significant correlations between the two surface metrics and trait anxiety levels, which were located around the lateral and central nucleus of right amygdala. Our results provided localized information for the association between amygdala and trait anxiety, and suggested a central role of the lateral and central nucleus of right amygdala on trait anxiety.

Two species within Dedroctonus frontalis (Coleoptera: Curculionidae): evidence from morphological, karyological, molecular, and crossing studies.

Science.gov (United States)

Francisco Armendariz-Toledano; Alicia Nino; Brian Sullivan; Jorge Macias-Samano; Javier Victor; Stephen R. Clarke; Gerardo Zuniga

2014-01-01

Dendroctonus frontalis Zimmermann is considered one of the most important economic and ecological forest pests in the United States, Mexico, and Central America. Recently, two apparent morphological variants of this species were discovered occurring syntopically in Central America and southern Mexico. Morphotype A beetles lack a series of Þne parallel ridges on the...

Ecological Models to Predict and Test the Effects of Chemical Stressors: Integration across 2 EPA STAR cooperative agreements

Science.gov (United States)

Accessible tools to quantify adverse outcomes pathways (AOPs) that can predict the ecological effects of chemicals and other stressors are a major goal of Chemical Safety and Sustainability research within US EPA’s Office of Research and Development. To address this goal, w...

EcoPAD, an interactive platform for near real-time ecological forecasting by assimilating data into model

Science.gov (United States)

MA, S.; Huang, Y.; Stacy, M.; Jiang, J.; Sundi, N.; Ricciuto, D. M.; Hanson, P. J.; Luo, Y.; Saruta, V.

2017-12-01

Ecological forecasting is critical in various aspects of our coupled human-nature systems, such as disaster risk reduction, natural resource management and climate change mitigation. Novel advancements are in urgent need to deepen our understandings of ecosystem dynamics, boost the predictive capacity of ecology, and provide timely and effective information for decision-makers in a rapidly changing world. Our study presents a smart system - Ecological Platform for Assimilation of Data (EcoPAD) - which streamlines web request-response, data management, model execution, result storage and visualization. EcoPAD allows users to (i) estimate model parameters or state variables, (ii) quantify uncertainty of estimated parameters and projected states of ecosystems, (iii) evaluate model structures, (iv) assess sampling strategies, (v) conduct ecological forecasting, and (vi) detect ecosystem acclimation to climate change. One of the key innovations of the web-based EcoPAD is the automated near- or real-time forecasting of ecosystem dynamics with uncertainty fully quantified. The user friendly webpage enables non-modelers to explore their data for simulation and data assimilation. As a case study, we applied EcoPAD to the Spruce and Peatland Responses Under Climatic and Environmental Change Experiment (SPRUCE), a whole ecosystem warming and CO2 enrichment treatment project in the northern peatland, assimilated multiple data streams into a process based ecosystem model, enhanced timely feedback between modelers and experimenters, ultimately improved ecosystem forecasting and made better use of current knowledge. Built in a framework with flexible API, EcoPAD is easily portable and will benefit scientific communities, policy makers as well as the general public.

Correlates between calcaneal morphology and locomotion in extant and extinct carnivorous mammals.

Science.gov (United States)

Panciroli, Elsa; Janis, Christine; Stockdale, Maximilian; Martín-Serra, Alberto

2017-10-01

Locomotor mode is an important component of an animal's ecology, relating to both habitat and substrate choice (e.g., arboreal versus terrestrial) and in the case of carnivores, to mode of predation (e.g., ambush versus pursuit). Here, we examine how the morphology of the calcaneum, the 'heel bone' in the tarsus, correlates with locomotion in extant carnivores. Other studies have confirmed the correlation of calcaneal morphology with locomotion behaviour and habitat. The robust nature of the calcaneum means that it is frequently preserved in the fossil record. Here, we employ linear measurements and 2D-geometric morphometrics on a sample of calcanea from eighty-seven extant carnivorans and demonstrate a signal of correlation between calcaneal morphology and locomotor mode that overrides phylogeny. We used this correlation to determine the locomotor mode, and hence aspects of the palaeobiology of, 47 extinct carnivorous mammal taxa, including both Carnivora and Creodonta. We found ursids (bears), clustered together, separate from the other carnivorans. Our results support greater locomotor diversity for nimravids (the extinct 'false sabertooths', usually considered to be more arboreal), than previously expected. However, there are limitations to interpretation of extinct taxa because their robust morphology is not fully captured in the range of modern carnivoran morphology. © 2017 Wiley Periodicals, Inc.

Computer Simulations Support a Morphological Contribution to BDNF Enhancement of Action Potential Generation

Directory of Open Access Journals (Sweden)

Domenico F Galati

2016-09-01

Full Text Available Abstract Brain-derived neurotrophic factor (BDNF regulates both action potential (AP generation and neuron morphology. However, whether BDNF-induced changes in neuron morphology directly impact AP generation is unclear. We quantified BDNF’s effect on cultured cortical neuron morphological parameters and found that BDNF stimulates dendrite growth and addition of dendrites while increasing both excitatory and inhibitory presynaptic inputs in a spatially restricted manner. To gain insight into how these combined changes in neuron structure and synaptic input impact AP generation, we used the morphological parameters we gathered to generate computational models. Simulations suggest that BDNF-induced neuron morphologies generate more APs under a wide variety of conditions. Synapse and dendrite addition have the greatest impact on AP generation. However, subtle alterations in excitatory/inhibitory synapse ratio and strength have a significant impact on AP generation when synaptic activity is low. Consistent with these simulations, BDNF rapidly enhances spontaneous activity in cortical cultures. We propose that BDNF promotes neuron morphologies that are intrinsically more efficient at translating barrages of synaptic activity into APs, which is a previously unexplored aspect of BDNF’s function.

Hybridization at an ecotone: ecological and genetic barriers between three Iberian vipers.

Science.gov (United States)

Tarroso, Pedro; Pereira, Ricardo J; Martínez-Freiría, Fernando; Godinho, Raquel; Brito, José C

2014-03-01

The formation of stable genetic boundaries between emerging species is often diagnosed by reduced hybrid fitness relative to parental taxa. This reduced fitness can arise from endogenous and/or exogenous barriers to gene flow. Although detecting exogenous barriers in nature is difficult, we can estimate the role of ecological divergence in driving species boundaries by integrating molecular and ecological niche modelling tools. Here, we focus on a three-way secondary contact zone between three viper species (Vipera aspis, V. latastei and V. seoanei) to test for the contribution of ecological divergence to the development of reproductive barriers at several species traits (morphology, nuclear DNA and mitochondrial DNA). Both the nuclear and mitochondrial data show that all taxa are genetically distinct and that the sister species V. aspis and V. latastei hybridize frequently and backcross over several generations. We find that the three taxa have diverged ecologically and meet at a hybrid zone coincident with a steep ecotone between the Atlantic and Mediterranean biogeographical provinces. Integrating landscape and genetic approaches, we show that hybridization is spatially restricted to habitats that are suboptimal for parental taxa. Together, these results suggest that niche separation and adaptation to an ecological gradient confer an important barrier to gene flow among taxa that have not achieved complete reproductive isolation. © 2014 John Wiley & Sons Ltd.

Anthropogenic landforms of warfare origin and their ecological significance: the Verdun Forest, NE France

Science.gov (United States)

De Matos Machado, Rémi; Amat, Jean-Paul; Arnaud-Fassetta, Gilles; Bétard, François; Bilodeau, Clélia; Jacquemot, Stéphanie; Toumazet, Jean-Pierre

2017-04-01

By its unprecedented industrial character, the First World War marked landscapes like no other conflict in the world. As a result of artillery bombardment and building facilities, the relief suffered major disturbances giving rise to millions anthropogenic landforms of warfare origin on the Western front: shell craters, trenches, shelters and gun sites. This landscape made of bumps and holes that dominated the lands of West Flanders and North-eastern France during the four years of war took chaotic aspects on the great battle sites. In some areas, substrate crushing by repeated bombings resulted in a field lowering of several metres. Although these geomorphological legacies of war are still present on these scarred lands, their effects on local environment and on present-day biodiversity patterns are not fully understood. On the battlefield of Verdun, where a huge number and range of conflict-induced landforms may be observed, special attention is being paid to the ecological significance of these anthropogenic landforms in a current landscape matrix dominated by forest. In 2013, an airborne LiDAR mission conducted over the battlefield has brought to light the relief inherited from the fighting that was until now concealed by the Verdun forest planted in the 1930's. Through a digital terrain model (DTM) with centimetre level accuracy, it is now possible to observe the smallest traces of the fighting. A first programmatic mapping work allowed to inventory and to locate these reliefs on the whole 10,000 hectares covered by the DTM. Also, the calculation of their geometry enabled us to quantify the erosion rate due to the military activities on the battlefield. On the basis of these morphometric measurements, a typology was developed to better appreciate the morphological diversity of conflict-induced landforms. The results show that these anthropogenic landforms are generally hollow. Because of this particular morphology, the conflict-induced landforms provide

Ecological half-lives of 9Sr and 137Cs in terrestrial and aquatic ecosystems

International Nuclear Information System (INIS)

Proehl, G.; Ehlken, S.; Fiedler, I.; Kirchner, G.; Klemt, E.; Zibold, G.

2006-01-01

This paper describes the long-term behaviour of 9 Sr and 137 Cs in foods, feeds and a variety of environmental media. The long-term behaviour is quantified by means of the ecological half-life which integrates all processes that cause a decrease of activity in a given medium such as leaching, fixation and erosion. A large number of long-term time series of concentrations of radiocaesium and radiostrontium in these media have been identified and re-evaluated using a standardised statistical procedure to establish reference data sets of ecological half-lives. By example of undisturbed soils and marine water bodies it is shown that the ecological half-life concept is questionable if the distribution of the radionuclide of interest within the medium studied is non-uniform and if mixing and transport processes within this medium, therefore, are of considerable importance during the time period of observation

Morphological, molecular and ecological aspects of the South American hypogeous fungi Alpova austroalnicola sp. nov.

Science.gov (United States)

Eduardo R. Nouhra; Laura S. Domínguez; Alejandra G. Becerra; James M. Trappe

2005-01-01

Field studies in Argentina's Yunga District revealed Alpova austroalnicola sp. nov., a hypogeous fungus associated with Alnus acuminata ssp, acuminata. Morphological and molecular studies based on amplification and sequencing of the nuclear LSU rDNA gene showed its unique identity within ...

Interpreting locomotor biomechanics from the morphology of human footprints.

Science.gov (United States)

Hatala, Kevin G; Wunderlich, Roshna E; Dingwall, Heather L; Richmond, Brian G

2016-01-01

Fossil hominin footprints offer unique direct windows to the locomotor behaviors of our ancestors. These data could allow a clearer understanding of the evolution of human locomotion by circumventing issues associated with indirect interpretations of habitual locomotor patterns from fossil skeletal material. However, before we can use fossil hominin footprints to understand better the evolution of human locomotion, we must first develop an understanding of how locomotor biomechanics are preserved in, and can be inferred from, footprint morphologies. In this experimental study, 41 habitually barefoot modern humans created footprints under controlled conditions in which variables related to locomotor biomechanics could be quantified. Measurements of regional topography (depth) were taken from 3D models of those footprints, and principal components analysis was used to identify orthogonal axes that described the largest proportions of topographic variance within the human experimental sample. Linear mixed effects models were used to quantify the influences of biomechanical variables on the first five principal axes of footprint topographic variation, thus providing new information on the biomechanical variables most evidently expressed in the morphology of human footprints. The footprint's overall depth was considered as a confounding variable, since biomechanics may be linked to the extent to which a substrate deforms. Three of five axes showed statistically significant relationships with variables related to both locomotor biomechanics and substrate displacement; one axis was influenced only by biomechanics and another only by the overall depth of the footprint. Principal axes of footprint morphological variation were significantly related to gait type (walking or running), kinematics of the hip and ankle joints and the distribution of pressure beneath the foot. These results provide the first quantitative framework for developing hypotheses regarding the

The need for standardisation: Exemplified by a description of the diversity, community structure and ecological indices of soil nematodes

NARCIS (Netherlands)

Griffiths, B.S.; de Groot, G. Arjen; Laros, I.; Stone, D.; Geisen, S.

2018-01-01

Molecular approaches are offering a supplement to, or even the possibility of replacing morphological identification of soil fauna, because of advantages for throughput, coverage and objectivity. We determined ecological indices of nematode community data from four sets of duplicate soil cores,

Quantitative morphological and compositional evaluation of laboratory prepared aluminoborosilicate glass surfaces

Energy Technology Data Exchange (ETDEWEB)

Gong, Yuxuan, E-mail: yg4@alfred.edu; Wren, Anthony W.; Mellott, Nathan P.

2015-01-01

Graphical abstract: - Highlights: • Aluminoborosilicate glass surfaces were prepared through both melting and polishing/etching and the surface composition and morphology were quantified as a function of processing method. • Glass surface morphology was quantified using PSD analysis, followed by both fractal and ABC model fitting, resulting in a comprehensive description of the spatial distribution of roughness. • All melt surfaces showed a depletion in Na, Ca, and B with respect to the bulk composition. Polished/etched surfaces showed a depletion in Na, B, and Al with respect to the bulk composition. • It was found that increasing heat treatment temperature of melt surfaces lead to a decrease in equivalent roughness and an increased spatial homogeneity of roughness while etching of polished ISG glass surfaces decreases the roughness and spatial distribution homogeneity of roughness. - Abstract: Surface finishing techniques including polishing, etching and heat treatment can modify the topography and the surface chemical composition of glasses. It is widely acknowledged that atomic force microscopy (AFM) can be used to quantify the morphology of surfaces, providing various parameters including average, peak-to-valley, and apparent root-mean-square roughness. Furthermore advanced power spectral density (PSD) analysis of AFM-derived surface profiles offers quantification of the spatial homogeneity of roughness values along different wavelengths, resulting in parameters including equivalent RMS, Hurst exponent, and fractal dimension. Outermost surface (∼8 nm) chemical composition can be quantitatively measured by X-ray photoelectron spectroscopy. In this paper, we first developed a series of surface finishing methods for an aluminoborosilicate glass system by polishing, etching or heat treatment. The chemical composition and environment of prepared glass surfaces were quantified by XPS and topographical analysis was carried out by fractal and k

MorphoTester: An Open Source Application for Morphological Topographic Analysis.

Directory of Open Access Journals (Sweden)

Julia M Winchester

Full Text Available The increased prevalence and affordability of 3D scanning technology is beginning to have significant effects on the research questions and approaches available for studies of morphology. As the current trend of larger and more precise 3D datasets is unlikely to slow in the future, there is a need for efficient and capable tools for high-throughput quantitative analysis of biological shape. The promise and the challenge of implementing relatively automated methods for characterizing surface shape can be seen in the example of dental topographic analysis. Dental topographic analysis comprises a suite of techniques for quantifying tooth surfaces and component features. Topographic techniques have provided insight on mammalian molar form-function relationships and these methods could be applied to address other topics and questions. At the same time implementing multiple complementary topographic methods can have high time and labor costs, and comparability of data formats and approaches is difficult to predict. To address these challenges I present MorphoTester, an open source application for visualizing and quantifying topography from 3D triangulated polygon meshes. This application is Python-based and is free to use. MorphoTester implements three commonly used dental topographic metrics-Dirichlet normal energy, relief index, and orientation patch count rotated (OPCR. Previous OPCR algorithms have used raster-based grid data, which is not directly interchangeable with vector-based triangulated polygon meshes. A 3D-OPCR algorithm is provided here for quantifying complexity from polygon meshes. The efficacy of this metric is tested in a sample of mandibular second molars belonging to four species of cercopithecoid primates. Results suggest that 3D-OPCR is at least as effective for quantifying complexity as previous approaches, and may be more effective due to finer resolution of surface data considered here. MorphoTester represents an advancement

Social Ecology, Deep Ecology and the Future of Green Political Thought.

Science.gov (United States)

Tokar, Brian

1988-01-01

Describes the differences which divide the social ecology movement and the Deep Ecology Movement. Discusses how each views population ecology, politics, natural resources, and ecological living. Calls for a unified ecological movement. (CW)

Landscape Ecology

DEFF Research Database (Denmark)

Christensen, Andreas Aagaard; Brandt, Jesper; Svenningsen, Stig Roar

2017-01-01

Landscape ecology is an interdisciplinary field of research and practice that deals with the mutual association between the spatial configuration and ecological functioning of landscapes, exploring and describing processes involved in the differentiation of spaces within landscapes......, and the ecological significance of the patterns which are generated by such processes. In landscape ecology, perspectives drawn from existing academic disciplines are integrated based on a common, spatially explicit mode of analysis developed from classical holistic geography, emphasizing spatial and landscape...... pattern analysis and ecological interaction of land units. The landscape is seen as a holon: an assemblage of interrelated phenomena, both cultural and biophysical, that together form a complex whole. Enduring challenges to landscape ecology include the need to develop a systematic approach able...

Detecting cryptic speciation in the widespread and morphologically conservative carpet chameleon (Furcifer lateralis) of Madagascar.

Science.gov (United States)

Florio, A M; Ingram, C M; Rakotondravony, H A; Louis, E E; Raxworthy, C J

2012-07-01

Species delimitation within recently evolved groups can be challenging because species may be difficult to distinguish morphologically. Following the General Lineage Concept, we apply a multiple evidence approach to assess species limits within the carpet chameleon Furcifer lateralis, which is endemic to Madagascar and exported in large numbers for the pet trade. Cryptic speciation within F. lateralis was considered likely because this species (1) has a vast distribution, (2) occupies exceptionally diverse habitats and (3) exhibits subtle regional differences in morphology. Phylogenetic trees reconstructed using nuclear and mitochondrial genes recovered three well-supported clades corresponding with geography. Morphological results based on canonical variates analysis show that these clades exhibit subtle differences in head casque morphology. Ecological niche modelling results found that these phylogenetic groups also occupy unique environmental space and exhibit patterns of regional endemism typical of other endemic reptiles. Combined, our findings provide diverse yet consistent evidence for the existence of three species. Consequently, we elevate the subspecies F. lateralis major to species rank and name a new species distributed in northern and western Madagascar. Initial ecological divergence, associated with speciation of F. lateralis in humid eastern habitat, fits the Ecographic Constraint model for species diversification in Madagascar. By contrast, the second speciation event provides some support for the Riverine Barrier model, with the Mangoky River possibly causing initial isolation between species. These findings thus support two contrasting models of speciation within closely related species and demonstrate the utility of applying a combined-evidence approach for detecting cryptic speciation. © 2012 The Authors. Journal of Evolutionary Biology © 2012 European Society For Evolutionary Biology.

Neuron Morphology Influences Axon Initial Segment Plasticity.

Science.gov (United States)

Gulledge, Allan T; Bravo, Jaime J

2016-01-01

In most vertebrate neurons, action potentials are initiated in the axon initial segment (AIS), a specialized region of the axon containing a high density of voltage-gated sodium and potassium channels. It has recently been proposed that neurons use plasticity of AIS length and/or location to regulate their intrinsic excitability. Here we quantify the impact of neuron morphology on AIS plasticity using computational models of simplified and realistic somatodendritic morphologies. In small neurons (e.g., dentate granule neurons), excitability was highest when the AIS was of intermediate length and located adjacent to the soma. Conversely, neurons having larger dendritic trees (e.g., pyramidal neurons) were most excitable when the AIS was longer and/or located away from the soma. For any given somatodendritic morphology, increasing dendritic membrane capacitance and/or conductance favored a longer and more distally located AIS. Overall, changes to AIS length, with corresponding changes in total sodium conductance, were far more effective in regulating neuron excitability than were changes in AIS location, while dendritic capacitance had a larger impact on AIS performance than did dendritic conductance. The somatodendritic influence on AIS performance reflects modest soma-to-AIS voltage attenuation combined with neuron size-dependent changes in AIS input resistance, effective membrane time constant, and isolation from somatodendritic capacitance. We conclude that the impact of AIS plasticity on neuron excitability will depend largely on somatodendritic morphology, and that, in some neurons, a shorter or more distally located AIS may promote, rather than limit, action potential generation.

Tracing Mantle Plumes: Quantifying their Morphology and Behavior from Seismic Tomography

Science.gov (United States)

O'Farrell, K. A.; Eakin, C. M.; Jones, T. D.; Garcia, E.; Robson, A.; Mittal, T.; Lithgow-Bertelloni, C. R.; Jackson, M. G.; Lekic, V.; Rudolph, M. L.

2016-12-01

Hotspot volcanism provides a direct link between the deep mantle and the surface, but the location, depth and source of the mantle plumes that feed hotspots are highly controversial. In order to address this issue it is important to understand the journey along which plumes have travelled through the mantle. The general behavior of plumes in the mantle also has the potential to tell us about the vigor of mantle convection, net rotation of the mantle, the role of thermal versus chemical anomalies, and important bulk physical properties of the mantle such as the viscosity profile. To address these questions we developed an algorithm to trace plume-like features in shear-wave (Vs) seismic tomographic models based on picking local minima in velocity and searching for continuous features with depth. We apply this method to several of the latest tomographic models and can recover 30 or more continuous plume conduits that are >750 km long. Around half of these can be associated with a known hotspot at the surface. We study the morphology of these plume chains and find that the largest lateral deflections occur near the base of the lower mantle and in the upper mantle. We analyze the preferred orientation of the plume deflections and their gradient to infer large scale mantle flow patterns and the depth of viscosity contrasts in the mantle respectively. We also retrieve Vs profiles for our traced plumes and compare with velocity profiles predicted for different mantle adiabat temperatures. We use this to constrain the thermal anomaly associated with these plumes. This thermal anomaly is then converted to a density anomaly and an upwelling velocity is derived. We compare this to buoyancy fluxes calculated at the surface and use this in conjunction with our measured plume tilts/deflections to estimate the strength of the "mantle wind".

Environmental risk of climate change and groundwater abstraction on stream ecological conditions

DEFF Research Database (Denmark)

Seaby, Lauren Paige; Bøgh, Eva; Jensen, Niels H.

with DAISY, a one dimensional crop model describing soil water dynamics in the root zone, and MIKE SHE, a distributed groundwater-surface water model. The relative and combined impacts on low flows, groundwater levels, and nitrate leaching are quantified and compared to assess the water resource sensitivity...... and risk to stream ecological conditions. We find low flow and annual discharge to be most impacted by scenarios of climate change, with high variation across climate models (+/- 40% change). Doubling of current groundwater abstraction rates reduces annual discharge by approximately 20%, with higher...... flows and groundwater levels are of interest, as they relate to aquatic habitat and nitrate leaching, respectively. This study evaluates the risk to stream ecological conditions for a lowland Danish catchment under multiple scenarios of climate change and groundwater abstraction. Projections of future...

Economical and ecological comparison of granular activated carbon (GAC) adsorber refill strategies.

Science.gov (United States)

Bayer, Peter; Heuer, Edda; Karl, Ute; Finkel, Michael

2005-05-01

Technical constraints can leave a considerable freedom in the design of a technology, production or service strategy. Choosing between economical or ecological decision criteria then characteristically leads to controversial solutions of ideal systems. For the adaptation of granular-activated carbon (GAC) fixed beds, various technical factors determine the adsorber volume required to achieve a desired service life. In considering carbon replacement and recycling, a variety of refill strategies are available that differ in terms of refill interval, respective adsorber volume, and time-dependent use of virgin, as well as recycled GAC. Focusing on the treatment of contaminant groundwater, we compare cost-optimal reactor configurations and refill strategies to the ecologically best alternatives. Costs and consumption of GAC are quantified within a technical-economical framework. The emissions from GAC production out of hard coal, transport and recycling are equally derived through a life cycle impact assessment. It is shown how high discount rates lead to a preference of small fixed-bed volumes, and accordingly, a high number of refills. For fixed discount rates, the investigation reveals that both the economical as well as ecological assessment of refill strategies are especially sensitive to the relative valuation of virgin and recycled GAC. Since recycling results in economic and ecological benefits, optimized systems thus may differ only slightly.

Ecology

Science.gov (United States)

Ternjej, Ivancica; Mihaljevic, Zlatko

2017-10-01

Ecology is a science that studies the mutual interactions between organisms and their environment. The fundamental subject of interest in ecology is the individual. Topics of interest to ecologists include the diversity, distribution and number of particular organisms, as well as cooperation and competition between organisms, both within and among ecosystems. Today, ecology is a multidisciplinary science. This is particularly true when the subject of interest is the ecosystem or biosphere, which requires the knowledge and input of biologists, chemists, physicists, geologists, geographists, climatologists, hydrologists and many other experts. Ecology is applied in a science of restoration, repairing disturbed sites through human intervention, in natural resource management, and in environmental impact assessments.

Nutrition, ecology and nutritional ecology: towardan integrated framework

DEFF Research Database (Denmark)

Raubenheimer, David; Simpson, Steven J.; Mayntz, David

2009-01-01

requirements: it should be nutritionally explicit, organismally explicit, and ecologically explicit. 4. We evaluate against these criteria four existing frameworks (Optimal Foraging Theory, Classical Insect Nutritional Ecology, the Geometric Framework for nutrition, and Ecological Stoichiometry), and conclude...... in its own right? 2. We suggest that the distinctive feature of nutritional ecology is its integrative nature, and that the field would benefit from more attention to formalizing a theoretical and quantitative framework for developing this. 3. Such a framework, we propose, should satisfy three minimal...

[Dynamic changes of ecological footprint and ecological capacity in Fujian Province].

Science.gov (United States)

Weng, Boqi; Wang, Yixiang; Huang, Yibin; Ying, Zhaoyang; Huang, Qinlou

2006-11-01

The analysis on the dynamic changes of ecological footprint and ecological capacity in Fujian Province showed that in 1999-2003, the ecological footprint per capita in the Province increased from 1.428 hm2 to 1.658 hm2, while the ecological capacity per capita decreased from 0.683 hm2 to 0.607 hm2, with an increased ecological deficit year after year. The contradiction between the ecological footprint and ecological capacity pricked up gradually, and the ecological environment was at risk. There existed a severe imbalance in the supply and demand of ecological footprint per capita. The main body of the demands was grassland and fossil fuel, accouting for 55.74% - 63.43% of the total, while their supply only occupied 0.77% - 0.82% and next to nothing of the ecological capacity per capita, respectively. As a whole, the ecological footprint per ten thousand yuan GDP declined in the five years, indicating that the resources use efficiency in the Province was improved gradually. Based on the analysis of the present situation of the economic development and resources distribution in the Province, the strategies on reducing ecological deficit were put forward.

Morphospaces of functionally analogous traits show ecological separation between birds and pterosaurs.

Science.gov (United States)

Chan, Nicholas R

2017-10-25

Birds originated and radiated in the presence of another group of flying vertebrates, the pterosaurs. Opinion is divided as to whether birds competitively displaced pterosaurs from small-body size niches or whether the two groups coexisted with little competition. Previous studies of Mesozoic birds and pterosaurs compared measurements of homologous limb bones to test these hypotheses. However, these characters probably reflect differing ancestries rather than ecologies. Here, competition and ecological separation were tested for using multivariate analyses of functionally equivalent morphological characters. As well as using characters from the fore- and hindlimbs, these analyses also included measurements of the lower jaw. The results of this study indicate that pterosaurs had relatively longer jaws, shorter metatarsals and shorter brachial regions compared with birds of similar size. Contrary to the results of previous studies, the distal wing was not important for separating the two clades in morphospace owing to the inclusion of the primary feathers in this unit. The differences found here indicate ecological separation based on differences in size, locomotory features and feeding adaptations. Thus, instead of one group displacing the other, birds and pterosaurs appear to have adopted distinctive ecological strategies throughout their period of coexistence. © 2017 The Author(s).

Marine microbial ecology: Reminiscence of the status and some suggestions for the way forward

Digital Repository Service at National Institute of Oceanography (India)

LokaBharathi, P.A.

communities are central to all processes . From traditional cultivation based experiments to today's molecular analyses based on metagenomics, major strides have been made. Molecular ecology made significant impact by revealing the true scope... environmental parameters are recorded together with diversity data, it would be possible to assess the impact of space, time, on microbial communities and quantify interactions among factors. The integration of laboratory-developed microbiological sensors...

Quantifying evolutionary dynamics from variant-frequency time series

Science.gov (United States)

Khatri, Bhavin S.

2016-09-01

From Kimura’s neutral theory of protein evolution to Hubbell’s neutral theory of biodiversity, quantifying the relative importance of neutrality versus selection has long been a basic question in evolutionary biology and ecology. With deep sequencing technologies, this question is taking on a new form: given a time-series of the frequency of different variants in a population, what is the likelihood that the observation has arisen due to selection or neutrality? To tackle the 2-variant case, we exploit Fisher’s angular transformation, which despite being discovered by Ronald Fisher a century ago, has remained an intellectual curiosity. We show together with a heuristic approach it provides a simple solution for the transition probability density at short times, including drift, selection and mutation. Our results show under that under strong selection and sufficiently frequent sampling these evolutionary parameters can be accurately determined from simulation data and so they provide a theoretical basis for techniques to detect selection from variant or polymorphism frequency time-series.

Alterations in archaeological bones thermally treated: structure and morphology

International Nuclear Information System (INIS)

Pijoan, C.M.; Mansilla, J.; Leboreiro, I.; Lara, V.H.; Bosch, P.

2004-01-01

Archaeological bones found close to Mexico city (Tlatelcomila) have been characterized by X-ray Diffraction, Small Angle X-ray Spectroscopy and Scanning Electron Microscopy. These techniques, which are not conventionally used in archaeological research, provided useful information. The boiled bones were clearly distinguished from grilled bones. The degree of deterioration of the bone structure was quantified through parameters such as gyration radius or fractal dimension. The morphology followed the structural modifications and changes resulting from thermic exposure. (Author) 23 refs., 1 tab., 2 figs

Rates of morphological evolution are heterogeneous in Early Cretaceous birds

Science.gov (United States)

Lloyd, Graeme T.

2016-01-01

The Early Cretaceous is a critical interval in the early history of birds. Exceptional fossils indicate that important evolutionary novelties such as a pygostyle and a keeled sternum had already arisen in Early Cretaceous taxa, bridging much of the morphological gap between Archaeopteryx and crown birds. However, detailed features of basal bird evolution remain obscure because of both the small sample of fossil taxa previously considered and a lack of quantitative studies assessing rates of morphological evolution. Here we apply a recently available phylogenetic method and associated sensitivity tests to a large data matrix of morphological characters to quantify rates of morphological evolution in Early Cretaceous birds. Our results reveal that although rates were highly heterogeneous between different Early Cretaceous avian lineages, consistent patterns of significantly high or low rates were harder to pinpoint. Nevertheless, evidence for accelerated evolutionary rates is strongest at the point when Ornithuromorpha (the clade comprises all extant birds and descendants from their most recent common ancestors) split from Enantiornithes (a diverse clade that went extinct at the end-Cretaceous), consistent with the hypothesis that this key split opened up new niches and ultimately led to greater diversity for these two dominant clades of Mesozoic birds. PMID:27053742

Tiger hair morphology and its variations for wildlife forensic investigation

Directory of Open Access Journals (Sweden)

Thitika Kitpipit

2013-11-01

Full Text Available Tiger population has dramatically decreased due to illegal consumption and commercialisation of their body parts. Frequently, hair samples are the only evidence found in the crime scene. Thus, they play an important role in species identification for wildlife forensic investigation. In this study, we provide the first in-depth report on a variety of qualitative and quantitative characteristics of tiger guard hairs (24 hairs per individual from four individuals. The proposed method could reduce subjectivity of expert opinions on species identification based on hair morphology. Variations in 23 hair morphological characteristics were quantified at three levels: hair section, body region, and intra-species. The results indicate statistically significant variations in most morphological characteristics in all levels. Intra-species variations of four variables, namely hair length, hair index, scale separation and scale pattern, were low. Therefore, identification of tiger hairs using these multiple features in combination with other characteristics with high inter-species variations (e.g. medulla type should bring about objective and accurate tiger hair identification. The method used should serve as a guideline and be further applied to other species to establish a wildlife hair morphology database. Statistical models could then be constructed to distinguish species and provide evidential values in terms of likelihood ratios.

Characterization of dispersed and aggregated Al2O3 morphologies for predicting nanofluid thermal conductivities

International Nuclear Information System (INIS)

Feng Xuemei; Johnson, Drew W.

2013-01-01

Nanofluids are reported to have enhanced thermal conductivities resulting from nanoparticle aggregation. The goal of this study was to explore through experimental measurements, dispersed and aggregated morphology effects on enhanced thermal conductivities for Al 2 O 3 nanoparticles with a primary size of 54.2 ± 2.0 nm. Aggregation effects were investigated by measuring thermal conductivity of different particle morphologies that occurred under different aggregation conditions. Fractal dimensions and aspect ratios were used to quantify the aggregation morphologies. Fractal dimensions were measured using static light scattering and imaging techniques. Aspect ratios were measured using dynamic light scattering, scanning electron microscopy, and atomic force microscopy. Results showed that the enhancements in thermal conductivity can be predicted with effective medium theory when aspect ratio was considered.

Morphology, ecology, and behaviour of Hylarana intermedia, a Western Ghats frog

Directory of Open Access Journals (Sweden)

Ambika Kamath

2016-06-01

Full Text Available Despite being common in the Western Ghats-Sri Lanka biodiversity hotspot, Golden-backed frogs (Hylarana, Ranidae remain poorly studied. In this paper, we present some preliminary data on the morphology, behaviour, and habitat use of Hylarana intermedia, a member of the Hylarana aurantiaca species group. We find evidence for female biased size dimorphism, as well as potential shape differences between the sexes in this species. Additionally, we investigate the relationships between traits that may contribute to male conspicuousness (call rates, dorsal coloration, and body size in two breeding habitats, a paddy field and a trench. Our results suggest both size-dependent and environment-dependent variation in call rate and colour in this species. Specifically, we find evidence against the adoption of sneaker mating strategies by small males in H. intermedia, and instead find variation both within and between populations in traits contributing to male conspicuousness. We conclude by proposing future directions for research on this common frog species.

Recent reticulate evolution in the ecologically dominant lineage of coccolithophores

Directory of Open Access Journals (Sweden)

El Mahdi eBendif

2016-05-01

Full Text Available The coccolithophore family Noëlaerhabdaceae contains a number of taxa that are very abundant in modern oceans, including the cosmopolitan bloom-forming Emiliania huxleyi. Introgressive hybridization has been suggested to account for incongruences between nuclear, mitochondrial and plastidial phylogenies of morphospecies within this lineage, but the number of species cultured to date remains rather limited. Here, we present the characterization of 5 new Noëlaerhabdaceae culture strains isolated from samples collected in the south-east Pacific Ocean. These were analyzed morphologically using scanning electron microscopy and phylogenetically by sequencing 5 marker genes (nuclear 18S and 28S rDNA, plastidial tufA, and mitochondrial cox1 and cox3 genes. Morphologically, one of these strains corresponded to Gephyrocapsa ericsonii and the four others to Reticulofenestra parvula. Ribosomal gene sequences were near identical between these new strains, but divergent from G. oceanica, G. muellerae and E. huxleyi. In contrast to the clear distinction in ribosomal phylogenies, sequences from other genomic compartments clustered with those of E. huxleyi strains with which they share an ecological range (i.e. warm temperate to tropical waters. These data provide strong support for the hypothesis of past (and potentially ongoing introgressive hybridization within this ecologically important lineage and for the transfer of R. parvula to Gephyrocapsa. These results have important implications for understanding the role of hybridization in speciation in vast ocean meta-populations of phytoplankton.

Quantifying Trade-Offs Between Economic and Ecological Objectives in Uneven-Aged Mixed- Species Forests in the Southern United States

Science.gov (United States)

Joseph Buongiorno; Benedict Schulte; Kenneth E. Skog

2004-01-01

This paper summarizes research on the management of uneven-aged loblolly pine-hardwood stands in the southern United States. This research was composed of three elements: (1) modeling of biological growth of uneven-aged stands of mixed loblolly pine and hardwood trees, (2) optimization to discover sustainable regimes that would best meet economic and ecological...

Ecological forecasting under climatic data uncertainty: a case study in phenological modeling

International Nuclear Information System (INIS)

Cook, Benjamin I; Terando, Adam; Steiner, Allison

2010-01-01

Forecasting ecological responses to climate change represents a challenge to the ecological community because models are often site-specific and climate data are lacking at appropriate spatial and temporal resolutions. We use a case study approach to demonstrate uncertainties in ecological predictions related to the driving climatic input data. We use observational records, derived observational datasets (e.g. interpolated observations from local weather stations and gridded data products) and output from general circulation models (GCM) in conjunction with site based phenology models to estimate the first flowering date (FFD) for three woody flowering species. Using derived observations over the modern time period, we find that cold biases and temperature trends lead to biased FFD simulations for all three species. Observational datasets resolved at the daily time step result in better FFD predictions compared to simulations using monthly resolution. Simulations using output from an ensemble of GCM and regional climate models over modern and future time periods have large intra-ensemble spreads and tend to underestimate observed FFD trends for the modern period. These results indicate that certain forcing datasets may be missing key features needed to generate accurate hindcasts at the local scale (e.g. trends, temporal resolution), and that standard modeling techniques (e.g. downscaling, ensemble mean, etc) may not necessarily improve the prediction of the ecological response. Studies attempting to simulate local ecological processes under modern and future climate forcing therefore need to quantify and propagate the climate data uncertainties in their simulations.

Advanced image processing methods as a tool to map and quantify different types of biological soil crust

Science.gov (United States)

Rodríguez-Caballero, Emilio; Escribano, Paula; Cantón, Yolanda

2014-04-01

Biological soil crusts (BSCs) modify numerous soil surface properties and affect many key ecosystem processes. As BSCs are considered one of the most important components of semiarid ecosystems, accurate characterisation of their spatial distribution is increasingly in demand. This paper describes a novel methodology for identifying the areas dominated by different types of BSCs and quantifying their relative cover at subpixel scale in a semiarid ecosystem of SE Spain. The approach consists of two consecutive steps: (i) First, Support Vector Machine (SVM) classification to identify the main ground units, dominated by homogenous surface cover (bare soil, cyanobacteria BSC, lichen BSC, green and dry vegetation), which are of strong ecological relevance. (ii) Spectral mixture analysis (SMA) of the ground units to quantify the proportion of each type of surface cover within each pixel, to correctly characterize the complex spatial heterogeneity inherent to semiarid ecosystems. SVM classification showed very good results with a Kappa coefficient of 0.93%, discriminating among areas dominated by bare soil, cyanobacteria BSC, lichen BSC, green and dry vegetation. Subpixel relative abundance images achieved relatively high accuracy for both types of BSCs (about 80%), whereas general overestimation of vegetation was observed. Our results open the possibility of introducing the effect of presence and of relative cover of BSCs in spatially distributed hydrological and ecological models, and assessment and monitoring aimed at reducing degradation in these areas.

BlastNeuron for Automated Comparison, Retrieval and Clustering of 3D Neuron Morphologies.

Science.gov (United States)

Wan, Yinan; Long, Fuhui; Qu, Lei; Xiao, Hang; Hawrylycz, Michael; Myers, Eugene W; Peng, Hanchuan

2015-10-01

Characterizing the identity and types of neurons in the brain, as well as their associated function, requires a means of quantifying and comparing 3D neuron morphology. Presently, neuron comparison methods are based on statistics from neuronal morphology such as size and number of branches, which are not fully suitable for detecting local similarities and differences in the detailed structure. We developed BlastNeuron to compare neurons in terms of their global appearance, detailed arborization patterns, and topological similarity. BlastNeuron first compares and clusters 3D neuron reconstructions based on global morphology features and moment invariants, independent of their orientations, sizes, level of reconstruction and other variations. Subsequently, BlastNeuron performs local alignment between any pair of retrieved neurons via a tree-topology driven dynamic programming method. A 3D correspondence map can thus be generated at the resolution of single reconstruction nodes. We applied BlastNeuron to three datasets: (1) 10,000+ neuron reconstructions from a public morphology database, (2) 681 newly and manually reconstructed neurons, and (3) neurons reconstructions produced using several independent reconstruction methods. Our approach was able to accurately and efficiently retrieve morphologically and functionally similar neuron structures from large morphology database, identify the local common structures, and find clusters of neurons that share similarities in both morphology and molecular profiles.

Floral traits and pollination ecology of European Arum hybrids.

Science.gov (United States)

Chartier, Marion; Liagre, Suzanne; Weiss-Schneeweiss, Hanna; Kolano, Bozena; Bessière, Jean-Marie; Schönenberger, Jürg; Gibernau, Marc

2016-02-01

Hybridisation is common in plants and can affect the genetic diversity and ecology of sympatric parental populations. Hybrids may resemble the parental species in their ecology, leading to competition and/or gene introgression; alternatively, they may diverge from the parental phenotypes, possibly leading to the colonisation of new ecological niches and to speciation. Here, we describe inflorescence morphology, ploidy levels, pollinator attractive scents, and pollinator guilds of natural hybrids of Arum italicum and A. maculatum (Araceae) from a site with sympatric parental populations in southern France to determine how these traits affect the hybrid pollination ecology. Hybrids were characterised by inflorescences with a size and a number of flowers more similar to A. italicum than to A. maculatum. In most cases, hybrid stamens were purple, as in A. maculatum, and spadix appendices yellow, as in A. italicum. Hybrid floral scent was closer to that of A. italicum, but shared some compounds with A. maculatum and comprised unique compounds. Also, the pollinator guild of the hybrids was similar to that of A. italicum. Nevertheless, the hybrids attracted a high proportion of individuals of the main pollinator of A. maculatum. We discuss the effects of hybridisation in sympatric parental zones in which hybrids exhibit low levels of reproductive success, the establishment of reproductive barriers between parental species, the role of the composition of floral attractive scents in the differential attraction of pollinators and in the competition between hybrids and their parental species, and the potential of hybridisation to give rise to new independent lineages.

Studies on Colombian cryptogams. V. Taxonomy, distribution and ecology of macrolichens of the Colombian Paramos: 1. Cladonia subgenus Cladina

NARCIS (Netherlands)

Sipman, H.J.M.; Cleef, A.M.

1979-01-01

Morphology, chemistry, distribution and ecology of 6 species of Cladonia subgenus Cladina (Lichenes) from the Colombian paramos are described: C. arcuata Ahti, C. boliviano Ahti, C. confusa Sant., C. polia Sant., C. rangiferina (L.) Wigg. var. abbayesii Ahti, and C. colombiana spec. Nov. C. bicolor

Dental Disparity and Ecological Stability in Bird-like Dinosaurs prior to the End-Cretaceous Mass Extinction.

Science.gov (United States)

Larson, Derek W; Brown, Caleb M; Evans, David C

2016-05-23

The causes, rate, and selectivity of the end-Cretaceous mass extinction continue to be highly debated [1-5]. Extinction patterns in small, feathered maniraptoran dinosaurs (including birds) are important for understanding extant biodiversity and present an enigma considering the survival of crown group birds (Neornithes) and the extinction of their close kin across the end-Cretaceous boundary [6]. Because of the patchy Cretaceous fossil record of small maniraptorans [7-12], this important transition has not been closely examined in this group. Here, we test the hypothesis that morphological disparity in bird-like dinosaurs was decreasing leading up to the end-Cretaceous mass extinction, as has been hypothesized in some dinosaurs [13, 14]. To test this, we examined tooth morphology, an ecological indicator in fossil reptiles [15-19], from over 3,100 maniraptoran teeth from four groups (Troodontidae, Dromaeosauridae, Richardoestesia, and cf. Aves) across the last 18 million years of the Cretaceous. We demonstrate that tooth disparity, a proxy for variation in feeding ecology, shows no significant decline leading up to the extinction event within any of the groups. Tooth morphospace occupation also remains static over this time interval except for increased size during the early Maastrichtian. Our data provide strong support that extinction within this group occurred suddenly after a prolonged period of ecological stability. To explain this sudden extinction of toothed maniraptorans and the survival of Neornithes, we propose that diet may have been an extinction filter and suggest that granivory associated with an edentulous beak was a key ecological trait in the survival of some lineages. Copyright © 2016 Elsevier Ltd. All rights reserved.

Driftcretions: The legacy impacts of driftwood on shoreline morphology

Science.gov (United States)

Kramer, Natalie; Wohl, Ellen

2015-07-01

This research demonstrates how vegetation interacts with physical processes to govern landscape development. We quantify and describe interactions among driftwood, sedimentation, and vegetation for Great Slave Lake, which is used as proxy for shoreline dynamics and landforms before deforestation and wood removal along major waterways. We introduce driftcretion to describe large, persistent concentrations of driftwood that interact with vegetation and sedimentation to influence shoreline evolution. We report the volume and distribution of driftwood along shorelines, the morphological impacts of driftwood delivery throughout the Holocene, and rates of driftwood accretion. Driftcretions facilitate the formation of complex, diverse morphologies that increase biological productivity and organic carbon capture and buffer against erosion. Driftcretions should be common on shorelines receiving a large wood supply and with processes which store wood permanently. We encourage others to work in these depositional zones to understand the physical and biological impacts of large wood export from river basins.

Effect of deletion of chitin synthase genes on mycelial morphology and culture viscosity in Aspergillus oryzae

DEFF Research Database (Denmark)

Müller, Christian; Hansen, K.; Szabo, Peter

2003-01-01

The objective of this study was to quantify the effect of disrupting two chitin synthases, chsB and csmA, on the morphology and rheology during batch cultivation of Aspergillus oryzae. The rheological properties were characterized in batch cultivations at different biomass concentrations (from 3...... broth was significantly affected by the biomass concentration, the morphology, and also by pH. The chsB disruption strain had lower consistency index K values for all biomass concentrations investigated, which is a desirable trait for industrial Aspergillus fermentations. (C) 2003 Wiley Periodicals, Inc....

Ecological and morphological profile of floating spherical Cladophora socialis aggregations in central Thailand.

Directory of Open Access Journals (Sweden)

Isao Tsutsui

Full Text Available The unique beauty of spherical aggregation forming algae has attracted much attention from both the scientific and lay communities. Several aegagropilous seaweeds have been identified to date, including the plants of genus Cladophora and Chaetomorpha. However, this phenomenon remains poorly understood. In July 2013, a mass occurrence of spherical Cladophora aggregations was observed in a salt field reservoir in Central Thailand. The aims of the present study were to describe the habitat of the spherical aggregations and confirm the species. We performed a field survey, internal and external morphological observations, pyrenoid ultrastructure observations, and molecular sequence analysis. Floating spherical Cladophora aggregations (1-8 cm in diameter were observed in an area ~560 m2, on the downwind side of the reservoir where there was water movement. Individual filaments in the aggregations were entangled in each other; consequently, branches growing in different directions were observed within a clump. We suggest that water movement and morphological characteristics promote the formation of spherical aggregations in this species. The molecular sequencing results revealed that the study species was highly homologous to both C. socialis and C. coelothrix. However, the diameter of the apical cells in the study species was less than that of C. coelothrix. The pyrenoid ultrastructure was more consistent with that of C. socialis. We conclude that the study species is C. socialis. This first record of spherical aggregations in this species advances our understanding of these formations. However, further detailed physical measurements are required to fully elucidate the mechanism behind these spherical formations.

Ecological and morphological profile of floating spherical Cladophora socialis aggregations in central Thailand.

Science.gov (United States)

Tsutsui, Isao; Miyoshi, Tatsuo; Sukchai, Halethichanok; Pinphoo, Piyarat; Aue-Umneoy, Dusit; Meeanan, Chonlada; Songphatkaew, Jaruwan; Klomkling, Sirimas; Yamaguchi, Iori; Ganmanee, Monthon; Sudo, Hiroyuki; Hamano, Kaoru

2015-01-01

The unique beauty of spherical aggregation forming algae has attracted much attention from both the scientific and lay communities. Several aegagropilous seaweeds have been identified to date, including the plants of genus Cladophora and Chaetomorpha. However, this phenomenon remains poorly understood. In July 2013, a mass occurrence of spherical Cladophora aggregations was observed in a salt field reservoir in Central Thailand. The aims of the present study were to describe the habitat of the spherical aggregations and confirm the species. We performed a field survey, internal and external morphological observations, pyrenoid ultrastructure observations, and molecular sequence analysis. Floating spherical Cladophora aggregations (1-8 cm in diameter) were observed in an area ~560 m2, on the downwind side of the reservoir where there was water movement. Individual filaments in the aggregations were entangled in each other; consequently, branches growing in different directions were observed within a clump. We suggest that water movement and morphological characteristics promote the formation of spherical aggregations in this species. The molecular sequencing results revealed that the study species was highly homologous to both C. socialis and C. coelothrix. However, the diameter of the apical cells in the study species was less than that of C. coelothrix. The pyrenoid ultrastructure was more consistent with that of C. socialis. We conclude that the study species is C. socialis. This first record of spherical aggregations in this species advances our understanding of these formations. However, further detailed physical measurements are required to fully elucidate the mechanism behind these spherical formations.

Application of graph theory to the morphological analysis of settlements

OpenAIRE

Szmytkie Robert

2017-01-01

In the following paper, the analyses of morphology of settlements were conducted using graph methods. The intention of the author was to create a quantifiable and simple measure, which, in a quantitative way, would express the degree of development of a graph (the spatial pattern of settlement). When analysing examples of graphs assigned to a set of small towns and large villages, it was noticed that the graph development index should depend on: a relative number of edges in relation to the n...

Diversity along a speciation continuum : ecology and morphology of northern European whitefish (Coregonus lavaretus)

OpenAIRE

Siwertsson, Anna

2012-01-01

Papers 1 and 4 of this thesis are not available in Munin: 1. Anna Siwertsson, Rune Knudsen and Per-Arne Amundsen: 'Temporal stability in gill raker numbers of subarctic European whitefish populations', Advances in Limnology (2012), vol. 63:229-240. Available at http://www.schweizerbart.de/papers/adv_limnology/detail/63/77932/Temporal_stability_ingill_raker_numbers_of_subarct 4. Anna Siwertsson, Rune Knudsen, Colin Adams and Per-Arne Amundsen: 'Replicated morphological divergence supports inci...

The better to eat you with: the comparative feeding morphology of phocid seals (Pinnipedia, Phocidae).

Science.gov (United States)

Kienle, Sarah S; Berta, Annalisa

2016-03-01

One adaptation crucial to the survival of mammalian lineages that secondarily transitioned from land to water environments was the ability to capture and consume prey underwater. Phocid seals have evolved diverse feeding strategies to feed in the marine environment, and the objectives of this study were to document the specialized feeding morphologies and identify feeding strategies used by extant phocids. This study used principal component analysis (PCA) to determine the major axes of diversification in the skull for all extant phocid taxa and the recently extinct Caribbean monk seal (n = 19). Prey data gathered from the literature and musculoskeletal data from dissections were included to provide a comprehensive description of each feeding strategy. Random Forest analysis was used to determine the morphological, ecological and phylogenetic variables that best described each feeding strategy. There is morphological evidence for four feeding strategies in phocids: filter; grip and tear; suction; and pierce feeding. These feeding strategies are supported by quantitative cranial and mandibular characters, dietary information, musculoskeletal data and, for some species, behavioral observations. Most phocid species are pierce feeders, using a combination of biting and suction to opportunistically catch prey. Grip and tear and filter feeding are specialized strategies with specific morphological adaptations. These unique adaptations have allowed leopard seals (Hydrurga leptonyx) and crabeater seals (Lobodon carcinophaga) to exploit novel ecological niches and prey types. This study provides the first cranial and mandibular morphological evidence for the use of specialized suction feeding in hooded seals (Cystophora cristata), northern elephant seals (Mirounga angustirostris) and southern elephant seals (Mirounga leonina). The most important variables in determining the feeding strategy of a given phocid species were cranial and mandibular shape, diet, and phylogeny

Quantifying and Valuing Potential Climate Change Impacts on Coral Reefs in the United States

Science.gov (United States)

Wobus, C. W.; Lane, D.; Buddemeier, R. W.; Ready, R. C.; Shouse, K. C.; Martinich, J.

2012-12-01

Global climate change presents a two-pronged threat to coral reef ecosystems: increasing sea surface temperatures will increase the likelihood of episodic bleaching events, while increasing ocean carbon dioxide concentrations will change the carbonate chemistry that drives coral growth. Because coral reefs have important societal as well as ecological benefits, climate change mitigation policies that ameliorate these impacts may create substantial economic value. We present a model that evaluates both the ecological and the economic impacts of climate change on coral reefs in the United States. We use a coral reef mortality and bleaching model to project future coral reef declines under a range of climate change policy scenarios for south Florida, Puerto Rico and Hawaii. Using a benefits transfer approach, the outputs from the physical model are then used to quantify the economic impacts of these coral reef declines for each of these regions. We find that differing climate change trajectories create substantial changes in projected coral cover and value for Hawaii, but that the ecological and economic benefits of more stringent emissions scenarios are less clear for Florida and Puerto Rico. Overall, our results indicate that the effectiveness of climate change mitigation policies may be region-specific, but that these policies could result in a net increase of nearly $10 billion in economic value from coral reef-related recreational activities alone, over the 21st century.

Ecological speciation by temporal isolation in a population of the stonefly Leuctra hippopus (Plecoptera, Leuctridae).

Science.gov (United States)

Boumans, Louis; Hogner, Silje; Brittain, John; Johnsen, Arild

2017-03-01

Stream dwelling invertebrates are ideal candidates for the study of ecological speciation as they are often adapted to particular environmental conditions within a stream and inhabit only certain reaches of a drainage basin, separated by unsuitable habitat. We studied an atypical population of the stonefly Leuctra hippopus at a site in central Norway, the Isterfoss rapids, in relation to three nearby and two remote conspecific populations. Adults of this population emerge about a month earlier than those of nearby populations, live on large boulders emerging from the rapids, and are short-lived. This population also has distinct morphological features and was studied earlier during the period 1975-1990. We reassessed morphological distinctness with new measurements and added several analyses of genetic distinctness based on mitochondrial and nuclear sequence markers, as well as AFLP fingerprinting and SNPs mined from RAD sequences. The Isterfoss population is shown to be most closely related to its geographical neighbors, yet clearly morphologically and genetically distinct and homogeneous. We conclude that this population is in the process of sympatric speciation, with temporal isolation being the most important direct barrier to gene flow. The shift in reproductive season results from the particular temperature and water level regime in the Isterfoss rapids. The distinct adult body shape and loss of flight are hypothesized to be an adaptation to the unusual habitat. Ecological diversification on small spatial and temporal scales is one of the likely causes of the high diversity of aquatic insects.

Remote Sensing Marine Ecology: Wind-driven algal blooms in the open oceans and their ecological impacts

Science.gov (United States)

Tang, DanLing

2016-07-01

Algal bloom not only can increase the primary production but also could result in negative ecological consequence, e.g., Harmful Algal Blooms (HABs). According to the classic theory for the formation of algal blooms "critical depth" and "eutrophication", oligotrophic sea area is usually difficult to form a large area of algal blooms, and actually the traditional observation is only sporadic capture to the existence of algal blooms. Taking full advantage of multiple data of satellite remote sensing, this study: 1), introduces "Wind-driven algal blooms in open oceans: observation and mechanisms" It explained except classic coastal Ekman transport, the wind through a variety of mechanisms affecting the formation of algal blooms. Proposed a conceptual model of "Strong wind -upwelling-nutrient-phytoplankton blooms" in Western South China Sea (SCS) to assess role of wind-induced advection transport in phytoplankton bloom formation. It illustrates the nutrient resources that support long-term offshore phytoplankton blooms in the western SCS; 2), Proposal of the theory that "typhoons cause vertical mixing, induce phytoplankton blooms", and quantify their important contribution to marine primary production; Proposal a new ecological index for typhoon. Proposed remote sensing inversion models. 3), Finding of the spatial and temporaldistributions pattern of harmful algal bloom (HAB)and species variations of HAB in the South Yellow Sea and East China Sea, and in the Pearl River estuary, and their oceanic dynamic mechanisms related with monsoon; The project developed new techniques and generated new knowledge, which significantly improved understanding of the formation mechanisms of algal blooms. 1), It proposed "wind-pump" mechanism integrates theoretical system combing "ocean dynamics, development of algal blooms, and impact on primary production", which will benefit fisheries management. 2), A new interdisciplinary subject "Remote Sensing Marine Ecology"(RSME) has been

Use of ecological exposure units in ecological risk assessment

International Nuclear Information System (INIS)

Ferenbaugh, R.; Myers, O.; Gallegos, A.; Breshears, D.; Ebinger, M.

1995-01-01

The traditional approach to ecological risk assessment at hazardous waste sites that are being evaluated for cleanup under CERCLA or RCRA requirements is to focus on the immediate impacts at or adjacent to a site. While this may be acceptable in some situations, it is not ecologically defensible in situations where there are numerous contaminated sites in proximity to each other. In the latter case, transport from the sites, potential cumulative effects, and wide-ranging receptors must be considered. The concept of the Ecological Exposure Unit (EEU) has been proposed to address this situation. Ecological Exposure Units are defined on the basis of ecological considerations and each EEU may contain several to many contaminated sites. The initial steps involved in performing ecological risk assessments using the EEU approach include (1) selection of appropriate receptors and assessment endpoints, and (2) geographical definition of EEUs. At Los Alamos National Laboratory, receptors have been identified and EEUs have been defined for these receptors. GIS is being used as a tool to map EEUs. Receptors include representatives from threatened or endangered species, species reflecting status of ecological health, species with social or cultural relevance, and other species of concern. After definition of EEUs, cumulative impacts of all stressors at all sites within each EEU must be evaluated. The two major advantages to performing ecological risk assessments using this approach are that risk assessments are performed in a more scientifically defensible manner because they are performed on ecologically defined units and that resources are used optimally by minimizing redundant remedial activities

Quantifying Riverscape Connectivity with Graph Theory

Science.gov (United States)

Carbonneau, P.; Milledge, D.; Sinha, R.; Tandon, S. K.

2013-12-01

Fluvial catchments convey fluxes of water, sediment, nutrients and aquatic biota. At continental scales, crustal topography defines the overall path of channels whilst at local scales depositional and/or erosional features generally determine the exact path of a channel. Furthermore, constructions such as dams, for either water abstraction or hydropower, often have a significant impact on channel networks.The concept of ';connectivity' is commonly invoked when conceptualising the structure of a river network.This concept is easy to grasp but there have been uneven efforts across the environmental sciences to actually quantify connectivity. Currently there have only been a few studies reporting quantitative indices of connectivity in river sciences, notably, in the study of avulsion processes. However, the majority of current work describing some form of environmental connectivity in a quantitative manner is in the field of landscape ecology. Driven by the need to quantify habitat fragmentation, landscape ecologists have returned to graph theory. Within this formal setting, landscape ecologists have successfully developed a range of indices which can model connectivity loss. Such formal connectivity metrics are currently needed for a range of applications in fluvial sciences. One of the most urgent needs relates to dam construction. In the developed world, hydropower development has generally slowed and in many countries, dams are actually being removed. However, this is not the case in the developing world where hydropower is seen as a key element to low-emissions power-security. For example, several dam projects are envisaged in Himalayan catchments in the next 2 decades. This region is already under severe pressure from climate change and urbanisation, and a better understanding of the network fragmentation which can be expected in this system is urgently needed. In this paper, we apply and adapt connectivity metrics from landscape ecology. We then examine the

Temperate Snake Community in South America: Is Diet Determined by Phylogeny or Ecology?

Science.gov (United States)

Etchepare, Eduardo G.

2015-01-01

Communities are complex and dynamic systems that change with time. The first attempts to explain how they were structured involve contemporary phenomena like ecological interactions between species (e.g., competition and predation) and led to the competition-predation hypothesis. Recently, the deep history hypothesis has emerged, which suggests that profound differences in the evolutionary history of organisms resulted in a number of ecological features that remain largely on species that are part of existing communities. Nevertheless, both phylogenetic structure and ecological interactions can act together to determine the structure of a community. Because diet is one of the main niche axes, in this study we evaluated, for the first time, the impact of ecological and phylogenetic factors on the diet of Neotropical snakes from the subtropical-temperate region of South America. Additionally, we studied their relationship with morphological and environmental aspects to understand the natural history and ecology of this community. A canonical phylogenetical ordination analysis showed that phylogeny explained most of the variation in diet, whereas ecological characters explained very little of this variation. Furthermore, some snakes that shared the habitat showed some degree of diet convergence, in accordance with the competition-predation hypothesis, although phylogeny remained the major determinant in structuring this community. The clade with the greatest variability was the subfamily Dipsadinae, whose members had a very different type of diet, based on soft-bodied invertebrates. Our results are consistent with the deep history hypothesis, and we suggest that the community under study has a deep phylogenetic effect that explains most of the variation in the diet. PMID:25945501

Temperate snake community in South America: is diet determined by phylogeny or ecology?

Directory of Open Access Journals (Sweden)

Gisela P Bellini

Full Text Available Communities are complex and dynamic systems that change with time. The first attempts to explain how they were structured involve contemporary phenomena like ecological interactions between species (e.g., competition and predation and led to the competition-predation hypothesis. Recently, the deep history hypothesis has emerged, which suggests that profound differences in the evolutionary history of organisms resulted in a number of ecological features that remain largely on species that are part of existing communities. Nevertheless, both phylogenetic structure and ecological interactions can act together to determine the structure of a community. Because diet is one of the main niche axes, in this study we evaluated, for the first time, the impact of ecological and phylogenetic factors on the diet of Neotropical snakes from the subtropical-temperate region of South America. Additionally, we studied their relationship with morphological and environmental aspects to understand the natural history and ecology of this community. A canonical phylogenetical ordination analysis showed that phylogeny explained most of the variation in diet, whereas ecological characters explained very little of this variation. Furthermore, some snakes that shared the habitat showed some degree of diet convergence, in accordance with the competition-predation hypothesis, although phylogeny remained the major determinant in structuring this community. The clade with the greatest variability was the subfamily Dipsadinae, whose members had a very different type of diet, based on soft-bodied invertebrates. Our results are consistent with the deep history hypothesis, and we suggest that the community under study has a deep phylogenetic effect that explains most of the variation in the diet.

Synthetical Analysis for Morphology, biological Species, and stable Isotopes (SAMSI) of single-cell planktonic foraminifer

Science.gov (United States)

Ujiie, Y.; Kimoto, K.; Ishimura, T.

2017-12-01

Planktonic foraminifers are widely used in the studies of paleontology and paleoceanography, because the morphology of their calcareous shells is enough highly variable to identify the morphospecies and the chemical composition of the shells reflect ambient seawater condition. Although the morphospecies were believed to represent environments associating with latitudinal temperature range of the world ocean, molecular phylogeographic studies have unveiled the presence of multiple biological species in a single morphospecies and their species-specific distributions. This implicates the actual complexity of planktonic foraminiferal ecology. Conversely, these biological species have a high potential for providing novel ecological and environmental information to us. In order to reassess the morphological and geochemical characters of biological species, the DNA extraction method with the guanidium isothiocyanate buffer was developed to preserve the calcareous shells. The present study carefully tested the physical and chemical damages of the DNA extraction process to the shells, by our novel approaches with geochemical analysis of the shells after non-destructive analysis for morphometrics on a same specimen. First, we checked the changes of the shell densities between pre- and post-DNA extraction by using the micro-focus X-ray CT (MXCT) scanning. Based on the simultaneous measurement of a sample and the standard material, we confirmed no significant changes to the shell densities through the DNA extraction process. As a next step, we compared stable oxygen and carbon isotopes among individuals of three sample sets: (1) no chemical and incubation as control, (2) incubation in the DNA extraction buffer at 65-70°C for 40 minutes as standard way, and (3) incubation in the DNA extraction buffer at 65-70°C for 120 minutes, by using the microscale isotopic analytical system (MICAL3c). Consequently, there were no significant differences among the three sample sets. These

A Nonstationary Markov Model Detects Directional Evolution in Hymenopteran Morphology.

Science.gov (United States)

Klopfstein, Seraina; Vilhelmsen, Lars; Ronquist, Fredrik

2015-11-01

Directional evolution has played an important role in shaping the morphological, ecological, and molecular diversity of life. However, standard substitution models assume stationarity of the evolutionary process over the time scale examined, thus impeding the study of directionality. Here we explore a simple, nonstationary model of evolution for discrete data, which assumes that the state frequencies at the root differ from the equilibrium frequencies of the homogeneous evolutionary process along the rest of the tree (i.e., the process is nonstationary, nonreversible, but homogeneous). Within this framework, we develop a Bayesian approach for testing directional versus stationary evolution using a reversible-jump algorithm. Simulations show that when only data from extant taxa are available, the success in inferring directionality is strongly dependent on the evolutionary rate, the shape of the tree, the relative branch lengths, and the number of taxa. Given suitable evolutionary rates (0.1-0.5 expected substitutions between root and tips), accounting for directionality improves tree inference and often allows correct rooting of the tree without the use of an outgroup. As an empirical test, we apply our method to study directional evolution in hymenopteran morphology. We focus on three character systems: wing veins, muscles, and sclerites. We find strong support for a trend toward loss of wing veins and muscles, while stationarity cannot be ruled out for sclerites. Adding fossil and time information in a total-evidence dating approach, we show that accounting for directionality results in more precise estimates not only of the ancestral state at the root of the tree, but also of the divergence times. Our model relaxes the assumption of stationarity and reversibility by adding a minimum of additional parameters, and is thus well suited to studying the nature of the evolutionary process in data sets of limited size, such as morphology and ecology. © The Author

Species delimitation and morphological divergence in the scorpion Centruroides vittatus (Say, 1821: insights from phylogeography.

Directory of Open Access Journals (Sweden)

Tsunemi Yamashita

Full Text Available Scorpion systematics and taxonomy have recently shown a need for revision, partially due to insights from molecular techniques. Scorpion taxonomy has been difficult with morphological characters as disagreement exists among researchers with character choice for adequate species delimitation in taxonomic studies. Within the family Buthidae, species identification and delimitation is particularly difficult due to the morphological similarity among species and extensive intraspecific morphological diversity. The genus Centruroides in the western hemisphere is a prime example of the difficulty in untangling the taxonomic complexity within buthid scorpions. In this paper, we present phylogeographic, Ecological Niche Modeling, and morphometric analyses to further understand how population diversification may have produced morphological diversity in Centruroides vittatus (Say, 1821. We show that C. vittatus populations in the Big Bend and Trans-Pecos region of Texas, USA are phylogeographically distinct and may predate the Last Glacial Maximum (LGM. In addition, we suggest the extended isolation of Big Bend region populations may have created the C. vittatus variant once known as C. pantheriensis.

Discontinuities concentrate mobile predators: Quantifying organism-environment interactions at a seascape scale

Science.gov (United States)

Kennedy, Christina G.; Mather, Martha E.; Smith, Joseph M.; Finn, John T.; Deegan, Linda A.

2016-01-01

Understanding environmental drivers of spatial patterns is an enduring ecological problem that is critical for effective biological conservation. Discontinuities (ecologically meaningful habitat breaks), both naturally occurring (e.g., river confluence, forest edge, drop-off) and anthropogenic (e.g., dams, roads), can influence the distribution of highly mobile organisms that have land- or seascape scale ranges. A geomorphic discontinuity framework, expanded to include ecological patterns, provides a way to incorporate important but irregularly distributed physical features into organism–environment relationships. Here, we test if migratory striped bass (Morone saxatilis) are consistently concentrated by spatial discontinuities and why. We quantified the distribution of 50 acoustically tagged striped bass at 40 sites within Plum Island Estuary, Massachusetts during four-monthly surveys relative to four physical discontinuities (sandbar, confluence, channel network, drop-off), one continuous physical feature (depth variation), and a geographic location variable (region). Despite moving throughout the estuary, striped bass were consistently clustered in the middle geographic region at sites with high sandbar area, close to channel networks, adjacent to complex confluences, with intermediate levels of bottom unevenness, and medium sized drop-offs. In addition, the highest striped bass concentrations occurred at sites with the greatest additive physical heterogeneity (i.e., where multiple discontinuities co-occurred). The need to incorporate irregularly distributed features in organism–environment relationships will increase as high-quality telemetry and GIS data accumulate for mobile organisms. The spatially explicit approach we used to address this challenge can aid both researchers who seek to understand the impact of predators on ecosystems and resource managers who require new approaches for biological conservation.

The role of ecological theory in microbial ecology.

Science.gov (United States)

Prosser, James I; Bohannan, Brendan J M; Curtis, Tom P; Ellis, Richard J; Firestone, Mary K; Freckleton, Rob P; Green, Jessica L; Green, Laura E; Killham, Ken; Lennon, Jack J; Osborn, A Mark; Solan, Martin; van der Gast, Christopher J; Young, J Peter W

2007-05-01

Microbial ecology is currently undergoing a revolution, with repercussions spreading throughout microbiology, ecology and ecosystem science. The rapid accumulation of molecular data is uncovering vast diversity, abundant uncultivated microbial groups and novel microbial functions. This accumulation of data requires the application of theory to provide organization, structure, mechanistic insight and, ultimately, predictive power that is of practical value, but the application of theory in microbial ecology is currently very limited. Here we argue that the full potential of the ongoing revolution will not be realized if research is not directed and driven by theory, and that the generality of established ecological theory must be tested using microbial systems.

Morphological Diversity and the Roles of Contingency, Chance and Determinism in African Cichlid Radiations

Science.gov (United States)

Young, Kyle A.; Snoeks, Jos; Seehausen, Ole

2009-01-01

Background Deterministic evolution, phylogenetic contingency and evolutionary chance each can influence patterns of morphological diversification during adaptive radiation. In comparative studies of replicate radiations, convergence in a common morphospace implicates determinism, whereas non-convergence suggests the importance of contingency or chance. Methodology/Principal Findings The endemic cichlid fish assemblages of the three African great lakes have evolved similar sets of ecomorphs but show evidence of non-convergence when compared in a common morphospace, suggesting the importance of contingency and/or chance. We then analyzed the morphological diversity of each assemblage independently and compared their axes of diversification in the unconstrained global morphospace. We find that despite differences in phylogenetic composition, invasion history, and ecological setting, the three assemblages are diversifying along parallel axes through morphospace and have nearly identical variance-covariance structures among morphological elements. Conclusions/Significance By demonstrating that replicate adaptive radiations are diverging along parallel axes, we have shown that non-convergence in the common morphospace is associated with convergence in the global morphospace. Applying these complimentary analyses to future comparative studies will improve our understanding of the relationship between morphological convergence and non-convergence, and the roles of contingency, chance and determinism in driving morphological diversification. PMID:19270732

Studying Behavioral Ecology on High School & College Campuses: A Practical Guide to Measuring Foraging Behavior Using Urban Wildlife

Science.gov (United States)

Baker, Mohammad A. Abu; Emerson, Sara E.; Brown, Joel S.

2015-01-01

We present a practical field exercise for ecology and animal behavior classes that can be carried out on campus, using urban wildlife. Students document an animal's feeding behavior to study its interactions with the surrounding environment. In this approach, an animal's feeding behavior is quantified at experimental food patches placed within its…

Development of ecological indicators of climate change based on lichen functional diversity

OpenAIRE

Matos, Paula Sofia Antunes

2016-01-01

Growing evidence shows us that climate has changed in the recent decades, and the scenario for the future will most likely worsen. A set of climate variables is being developed to monitor climate change, but this is not enough to keep track its effects on ecosystems. It’s imperative to understand and quantify how ecosystems functioning are affected by and respond to these changes, and ecological indicators based on biodiversity metrics are one of the tools to do this. The...

The ecological economics: An ecological economics

International Nuclear Information System (INIS)

Castiblanco R, Carmenza

2007-01-01

Ecological Economics arise as a scientific discipline aimed to integrate concepts of economics, ecology, thermodynamics, ethic and other natural and social sciences in order to incorporate a biophysical and integrated perspective of the inter dependences between economies and environment, from a plural conception and a methodology beyond disciplines. Ecological Economics studies the black box of economic processes usually excluded of the traditional economics: thermodynamics and ecology. Although it is relatively a new field of study, it has been strengthening its theoretical framework with scientific basis and analytic principles that lead to its identification as a new discipline that show a whole new paradigm. The scope of this article is to show the conceptual and methodological bases, the main founders, approaches and central debates of this new discipline. This brief introduction is a preamble to the papers of the meeting Ecological Economics: a perspective for Colombia included in this number, that took place on September 22 - 27 of 2007, at the National University of Colombia at Bogota. During tree days national and international experts, professors, researchers, workers of environmental sector and people interested on environmental issues joined together to know the conceptual and methodological achievements reached of this discipline; as well as to analyse and evaluate the environmental problems of the country, from the systemic, interdisciplinary and general perspective that it promotes

Toward an integrated theory of spatial morphology and resilient urban systems

Directory of Open Access Journals (Sweden)

Lars Marcus

2014-12-01

Full Text Available We take the first step in the development of a new field of research with the aim of merging spatial morphology and resilience science. This involves a revisiting and reunderstanding of the meaning of sustainable urban form. We briefly describe the fields of resilience science and spatial morphology. Drawing on a selected set of propositions in both fields, we put urban form in the context of the adaptive renewal cycle, a dynamic framework model used in resilience science to capture the dynamics of complex adaptive systems, of which urban systems are prime examples. We discuss the insights generated in this endeavor, dealing with some key morphological aspects in relation to four key attributes of resilience, i.e., "change," "diversity," "self-organization," and "learning." We discuss and relate these to urban form and other social variables, with special attention paid to the "backloop phase" of the adaptive renewal cycle. We conclude by postulating ways in which resilience thinking could contribute to the development of a new research frontier for addressing designs for resilient urban social-ecological systems, and end by proposing three strategic areas of research in such a field.

Morphology, Kinematics, and Dynamics: The Mechanics of Suction Feeding in Fishes.

Science.gov (United States)

Day, Steven W; Higham, Timothy E; Holzman, Roi; Van Wassenbergh, Sam

2015-07-01

Suction feeding is pervasive among aquatic vertebrates, and our understanding of the functional morphology and biomechanics of suction feeding has recently been advanced by combining experimental and modeling approaches. Key advances include the visualization of the patterns of flow in front of the mouth of a feeding fish, the measurement of pressure inside their mouth cavity, and the employment of analytical and computational models. Here, we review the key components of the morphology and kinematics of the suction-feeding system of anatomically generalized, adult ray-finned fishes, followed by an overview of the hydrodynamics involved. In the suction-feeding apparatus, a strong mechanistic link among morphology, kinematics, and the capture of prey is manifested through the hydrodynamic interactions between the suction flows and solid surfaces (the mouth cavity and the prey). It is therefore a powerful experimental system in which the ecology and evolution of the capture of prey can be studied based on first principals. © The Author 2015. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

The Political Economy of the Water Footprint: A Cross-National Analysis of Ecologically Unequal Exchange

Directory of Open Access Journals (Sweden)

Jared B. Fitzgerald

2016-12-01

Full Text Available Water scarcity is an important social and ecological issue that is becoming increasingly problematic with the onset of climate change. This study explores the extent to which water resources in developing countries are affected by the vertical flow of exports to high-income countries. In examining this question, the authors engage the sociological theory of ecologically unequal exchange, which argues that high-income countries are able to partially externalize the environmental costs of their consumption to lower-income countries. The authors use a relatively new and underutilized measure of water usage, the water footprint, which quantifies the amount of water used in the entire production process. Ordinary least squares (OLS and robust regression techniques are employed in the cross-national analysis of 138 countries. The results provide partial support of the propositions of ecologically unequal exchange theory. In particular, the results highlight the importance of structural position in the global economy for understanding the effects of trade on water resources.

Morphological Plant Modeling: Unleashing Geometric and Topological Potential within the Plant Sciences

Science.gov (United States)

Bucksch, Alexander; Atta-Boateng, Acheampong; Azihou, Akomian F.; Battogtokh, Dorjsuren; Baumgartner, Aly; Binder, Brad M.; Braybrook, Siobhan A.; Chang, Cynthia; Coneva, Viktoirya; DeWitt, Thomas J.; Fletcher, Alexander G.; Gehan, Malia A.; Diaz-Martinez, Diego Hernan; Hong, Lilan; Iyer-Pascuzzi, Anjali S.; Klein, Laura L.; Leiboff, Samuel; Li, Mao; Lynch, Jonathan P.; Maizel, Alexis; Maloof, Julin N.; Markelz, R. J. Cody; Martinez, Ciera C.; Miller, Laura A.; Mio, Washington; Palubicki, Wojtek; Poorter, Hendrik; Pradal, Christophe; Price, Charles A.; Puttonen, Eetu; Reese, John B.; Rellán-Álvarez, Rubén; Spalding, Edgar P.; Sparks, Erin E.; Topp, Christopher N.; Williams, Joseph H.; Chitwood, Daniel H.

2017-01-01

The geometries and topologies of leaves, flowers, roots, shoots, and their arrangements have fascinated plant biologists and mathematicians alike. As such, plant morphology is inherently mathematical in that it describes plant form and architecture with geometrical and topological techniques. Gaining an understanding of how to modify plant morphology, through molecular biology and breeding, aided by a mathematical perspective, is critical to improving agriculture, and the monitoring of ecosystems is vital to modeling a future with fewer natural resources. In this white paper, we begin with an overview in quantifying the form of plants and mathematical models of patterning in plants. We then explore the fundamental challenges that remain unanswered concerning plant morphology, from the barriers preventing the prediction of phenotype from genotype to modeling the movement of leaves in air streams. We end with a discussion concerning the education of plant morphology synthesizing biological and mathematical approaches and ways to facilitate research advances through outreach, cross-disciplinary training, and open science. Unleashing the potential of geometric and topological approaches in the plant sciences promises to transform our understanding of both plants and mathematics. PMID:28659934

Morphological Plant Modeling: Unleashing Geometric and Topological Potential within the Plant Sciences

Directory of Open Access Journals (Sweden)

Alexander Bucksch

2017-06-01

Full Text Available The geometries and topologies of leaves, flowers, roots, shoots, and their arrangements have fascinated plant biologists and mathematicians alike. As such, plant morphology is inherently mathematical in that it describes plant form and architecture with geometrical and topological techniques. Gaining an understanding of how to modify plant morphology, through molecular biology and breeding, aided by a mathematical perspective, is critical to improving agriculture, and the monitoring of ecosystems is vital to modeling a future with fewer natural resources. In this white paper, we begin with an overview in quantifying the form of plants and mathematical models of patterning in plants. We then explore the fundamental challenges that remain unanswered concerning plant morphology, from the barriers preventing the prediction of phenotype from genotype to modeling the movement of leaves in air streams. We end with a discussion concerning the education of plant morphology synthesizing biological and mathematical approaches and ways to facilitate research advances through outreach, cross-disciplinary training, and open science. Unleashing the potential of geometric and topological approaches in the plant sciences promises to transform our understanding of both plants and mathematics.

Movement, Abundance Patterns, and Foraging Ecology of the California Two Spot Octopus, Octopus bimaculatus

OpenAIRE

Hofmeister, Jennifer Krista Kaulalani

2015-01-01

Understanding the reciprocal interactions between animal behavior and other inter-related systems such as physiology, morphology, ecology, and evolution has been called a “Grand Challenge” for organismal biology. Behavior offers two unique contributions to our understanding of organism response to environmental change: 1) behavior is a rapid and reversible response, and 2) organisms can directly influence their surrounding environment, and thus the stimuli their physiological and morphologica...

Neuron Morphology Influences Axon Initial Segment Plasticity123

Science.gov (United States)

2016-01-01

In most vertebrate neurons, action potentials are initiated in the axon initial segment (AIS), a specialized region of the axon containing a high density of voltage-gated sodium and potassium channels. It has recently been proposed that neurons use plasticity of AIS length and/or location to regulate their intrinsic excitability. Here we quantify the impact of neuron morphology on AIS plasticity using computational models of simplified and realistic somatodendritic morphologies. In small neurons (e.g., dentate granule neurons), excitability was highest when the AIS was of intermediate length and located adjacent to the soma. Conversely, neurons having larger dendritic trees (e.g., pyramidal neurons) were most excitable when the AIS was longer and/or located away from the soma. For any given somatodendritic morphology, increasing dendritic membrane capacitance and/or conductance favored a longer and more distally located AIS. Overall, changes to AIS length, with corresponding changes in total sodium conductance, were far more effective in regulating neuron excitability than were changes in AIS location, while dendritic capacitance had a larger impact on AIS performance than did dendritic conductance. The somatodendritic influence on AIS performance reflects modest soma-to-AIS voltage attenuation combined with neuron size-dependent changes in AIS input resistance, effective membrane time constant, and isolation from somatodendritic capacitance. We conclude that the impact of AIS plasticity on neuron excitability will depend largely on somatodendritic morphology, and that, in some neurons, a shorter or more distally located AIS may promote, rather than limit, action potential generation. PMID:27022619

Three-Dimensional Morphology of a Coronal Prominence Cavity

Science.gov (United States)

Gibson, S. E.; Kucera, T. A.; Rastawicki, D.; Dove, J.; deToma, G.; Hao, J.; Hill, S.; Hudson, H. S.; Marque, C.; McIntosh, P. S.;

Morphology and digitally aided morphometry of the human paracentral lobule.

Science.gov (United States)

Spasojević, Goran; Malobabic, Slobodan; Pilipović-Spasojević, Olivera; Djukić-Macut, Nataša; Maliković, Aleksandar

2013-02-01

The human paracentral lobule, the junction of the precentral and postcentral gyri at the medial hemispheric surface, contains several important functional regions, and its variable morphology requires exact morphological and quantitativedata. In order to obtain precise data we investigated the morphology of the paracentral lobule and quantified its visible (extrasulcal) surface. This surface corresponds to commonly used magnetic resonance imaging scout images. We studied 84 hemispheres of adult persons (42 brains; 26 males and 16 females; 20-65 years) fixed in neutral formalin for at least 4 weeks. The medial hemispheric surface was photographed at standard distance and each digital photo was calibrated. Using the intercommissural line system (commissura anterior-commissura posterior or CA-CP line), we performed standardised measurements of the paracentral lobule. Exact determination of its boundaries and morphological types was followed by digital morphometry of its extrasulcal surface using AutoCAD software. We found two distinct morphological types of the human paracentral lobule: continuous type, which was predominant (95.2%), and rare segmented type (4.8%). In hemispheres with segmented cingulate sulcus we also found the short transitional lobulo-limbic gyrus (13.1%). The mean extrasulcal surface of the left paracentral lobule was significantly larger, both in males (left 6.79 cm2 vs. right 5.76 cm2) and in females (left 6.05 cm2 vs. right 5.16 cm2). However, even larger average surfaces in males were not significantly different than the same in females. Reported morphological and quantitative data will be useful during diagnostics and treatment of pathologies affecting the human paracentral lobule, and in further studies of its cytoarchitectonic and functional parcellations.

Ecologies of Learning, Ecologies of Creativity

DEFF Research Database (Denmark)

Høyrup, Helene

in the light of the new Danish school reform. How can different learning institutions contribute to a “joint” ecology of learning? What would the benefits be from this in terms of young people’s literacies? On what theoretical basis can such an ecology and co-creation take place? And what kind of didactics...

Revitalizing traditional ecological knowledge: a study in an Alpine rural community.

Science.gov (United States)

Ianni, Elena; Geneletti, Davide; Ciolli, Marco

2015-07-01

This study aims to contribute to the debate on the value and the role of ecological knowledge in modern conservation strategies, with reference to the results of a case study conducted in the community of Montagne, located within a World Heritage site in the Italian Alps. This community is a paradigmatic example of the multiple transformations experienced by cultural landscapes in Alpine areas under the influence of global change. This study seeks to understand whether ecological knowledge is still in place in the community, and what the relationship is between the knowledge transmission and land use and social changes that have occurred in recent decades. To that end, the community is described by identifying the key variables (social, institutional, and ecological) that have historically shaped the landscape and the future priorities of the residents. Forest expansion, the most significant change in land use in the last 60 years, is analyzed using aerial photos; changes in biodiversity-related knowledge in the community are quantified by analyzing the inter-generational differences in plant species recognition. Results are discussed in the context of the current situation of the Montagne community, and the recommendation is made that policies and actions to promote traditional ecological knowledge protection or recovery in Europe be viewed as an important part of the recovery of community sovereignty and vitality. Lastly, concrete actions that can be implemented in our case study are proposed.

Revitalizing Traditional Ecological Knowledge: A Study in an Alpine Rural Community

Science.gov (United States)

Ianni, Elena; Geneletti, Davide; Ciolli, Marco

2015-07-01

This study aims to contribute to the debate on the value and the role of ecological knowledge in modern conservation strategies, with reference to the results of a case study conducted in the community of Montagne, located within a World Heritage site in the Italian Alps. This community is a paradigmatic example of the multiple transformations experienced by cultural landscapes in Alpine areas under the influence of global change. This study seeks to understand whether ecological knowledge is still in place in the community, and what the relationship is between the knowledge transmission and land use and social changes that have occurred in recent decades. To that end, the community is described by identifying the key variables (social, institutional, and ecological) that have historically shaped the landscape and the future priorities of the residents. Forest expansion, the most significant change in land use in the last 60 years, is analyzed using aerial photos; changes in biodiversity-related knowledge in the community are quantified by analyzing the inter-generational differences in plant species recognition. Results are discussed in the context of the current situation of the Montagne community, and the recommendation is made that policies and actions to promote traditional ecological knowledge protection or recovery in Europe be viewed as an important part of the recovery of community sovereignty and vitality. Lastly, concrete actions that can be implemented in our case study are proposed.

Soedra's ecological forest management plans. Effects on production and economy

International Nuclear Information System (INIS)

Viklund, E.

1998-01-01

In 1995 SOEDRA Skog, Sweden's largest forest owners association, started making ecological forest management plans, Groena skogsbruksplaner. The ecological forest management plans are divided into different compartments in which the management is adapted to the present ecological conditions. The stands are divided into four different categories depending on the different values of nature conservation. The object of this study was to find an easy method to quantify and describe the effects of nature conservation on economy and forest production in SOEDRA:s ecological forest management plans. The developed and purposed method, called PLAN-metoden, does not consider the interests, measures beyond the period of the plan, or losses due to snow or wind. It calculates the difference between the purposed measures in the ecological management plan and an alternative with management according to the requirements of the present Forestry Act. The economic effects of nature conservation varies between a net profit of 0,3% and a cost of 9,1% when calculated with the cash-flow method. The average decrease of possible cutting of merchantable timber was 11,3% and varies between 3,1 and 32,9%. The average decrease of cutting possibilities was 12,9% and varies between a decrease of 0,7% and a decrease of 28,3% when calculated with a present value method. Mainly mature, well-stocked compartments, which are considered not to be managed in the future, give rise to high costs. Properties with unprofitable thinnings and costly scarification, regeneration and cleaning seem to be favoured by the nature conservation in the plans. The Ecological management plans are expected to be of great importance to the members of SOEDRA. The interest in nature conservation is larger than that of economical issues. In order to avoid unsatisfactory results the planning should be accomplished in close personal contact with the forest owner Examination paper 1998-1. 21 refs, 2 figs, 39 tabs

Inferring ecological explanations for biogeographic boundaries of parapatric Asian mountain frogs.

Science.gov (United States)

Hu, Junhua; Jiang, Jianping

2018-02-02

Identifying and understanding the mechanisms that shape barriers to dispersal and resulting biogeographic boundaries has been a longstanding, yet challenging, goal in ecology, evolution and biogeography. Characterized by stable, adjacent ranges, without any intervening physical barriers, and limited, if any, range overlap in a narrow contact zone, parapatric species are an interesting system for studying biogeographic boundaries. The geographic ranges of two parapatric frog species, Feirana quadranus and F. taihangnica, meet in a contact zone within the Qinling Mountains, an important watershed for East Asia. To identify possible ecological determinants of the parapatric range boundaries for two closely related frog species, we quantified the extent of their niche differentiation in both geographical and environmental space combining ecological niche models with an ordination technique. We tested two alternative null hypotheses (sharp environmental gradients versus a ribbon of unsuitable habitat dividing two highly suitable regions) for biogeographic boundaries, against the null expectation that environmental variation across a given boundary is no greater than expected by chance. We found that the niches of these two parapatric species are more similar than expected by chance, but not equivalent. No sharp environmental gradient was found, while a ribbon of unsuitable habitat did act as a barrier for F. quadranus, but not for F. taihangnica. Integrating our findings with historical biogeographic information, our results suggest that at a contact zone, environmental tolerance restricted F. quadranus from dispersing further north, while interspecific competition most likely prevented the southward expansion of F. taihangnica. This study highlights the importance of both climate and competition in exploring ecological explanations for parapatric range boundaries between ecologically similar frog species, in particular under the effects of changing climate.

Larval morphology and phylogenetic position of Drusus balcanicus, Drusus botosaneanui, Drusus serbicus and Drusus tenellus (Trichoptera: Limnephilidae: Drusinae)

Science.gov (United States)

WARINGER, JOHANN; GRAF, WOLFRAM; BÁLINT, MIKLÓS; KUČINIĆ, MLADEN; PAULS, STEFFEN U.; PREVIŠIĆ, ANA; KERESZTES, LUJZA; IBRAHIMI, HALIL; ŽIVIĆ, IVANA; BJELANOVIĆ, KATARINA; KRPAČ, VLADIMIR; VITECEK, SIMON

2016-01-01

In a recent 3–gene phylogeny of the Trichoptera subfamily Drusinae Banks, 1916 molecular data clearly correlated with the morphology and feeding ecology of larvae. The largest of three main groups, the Drusinae grazer clade, exhibits an unusual larval feeding ecology for Limnephilidae, and is the most diverse group. In this paper we describe four previously unknown Drusinae larvae from this clade: Drusus balcanicus Kumanski, 1973 (micro–endemic to Eastern Balkans); Drusus botosaneanui Kumanski, 1968 (Dinaric Western Balkans, Hellenic and Eastern Balkan, Asia Minor), Drusus serbicus Marinković-Gospodnetić, 1971a (micro–endemic to Dinaric Western Balkans); and Drusus tenellus (Klapálek, 1898) (Carpathians, Dinaric Eastern Balkans). Characteristically, the larvae of these species develop toothless mandibles typical for the Drusinae grazer clade. Larvae and adults were unambiguously associated by a phylogenetic approach based on two mitochondrial (mtCOI, mtLSU= 16S rDNA) and two nuclear genes (nuWG, nuCAD). In addition, information on the morphology of the larvae is given and the diagnostic features necessary for identification are illustrated. PMID:26997882

Using Morphological, Molecular and Climatic Data to Delimitate Yews along the Hindu Kush-Himalaya and Adjacent Regions

Science.gov (United States)

Poudel, Ram C.; Möller, Michael; Gao, Lian-Ming; Ahrends, Antje; Baral, Sushim R.; Liu, Jie; Thomas, Philip; Li, De-Zhu

2012-01-01

Background Despite the availability of several studies to clarify taxonomic problems on the highly threatened yews of the Hindu Kush-Himalaya (HKH) and adjacent regions, the total number of species and their exact distribution ranges remains controversial. We explored the use of comprehensive sets of morphological, molecular and climatic data to clarify taxonomy and distributions of yews in this region. Methodology/Principal Findings A total of 743 samples from 46 populations of wild yew and 47 representative herbarium specimens were analyzed. Principle component analyses on 27 morphological characters and 15 bioclimatic variables plus altitude and maximum parsimony analysis on molecular ITS and trnL-F sequences indicated the existence of three distinct species occurring in different ecological (climatic) and altitudinal gradients along the HKH and adjacent regions Taxus contorta from eastern Afghanistan to the eastern end of Central Nepal, T. wallichiana from the western end of Central Nepal to Northwest China, and the first report of the South China low to mid-elevation species T. mairei in Nepal, Bhutan, Northeast India, Myanmar and South Vietnam. Conclusion/Significance The detailed sampling and combination of different data sets allowed us to identify three clearly delineated species and their precise distribution ranges in the HKH and adjacent regions, which showed no overlap or no distinct hybrid zone. This might be due to differences in the ecological (climatic) requirements of the species. The analyses further provided the selection of diagnostic morphological characters for the identification of yews occurring in the HKH and adjacent regions. Our work demonstrates that extensive sampling combined with the analysis of diverse data sets can reliably address the taxonomy of morphologically challenging plant taxa. PMID:23056501

Spatio-temporal heterogeneity of riparian soil morphology in a restored floodplain

Science.gov (United States)

Fournier, B.; Guenat, C.; Bullinger-Weber, G.; Mitchell, E. A. D.

2013-10-01

Floodplains have been intensively altered in industrialized countries, but are now increasingly being restored. It is therefore important to assess the effect of these restoration projects on the aquatic and terrestrial components of ecosystems. However, despite being functionally crucial components of terrestrial ecosystems, soils are generally overlooked in floodplain restoration assessments. We studied the spatio-temporal heterogeneity of soil morphology in a restored (riverbed widening) river reach along the River Thur (Switzerland) using three criteria (soil diversity, dynamism and typicality) and their associated indicators. We hypothesized that these criteria would correctly discriminate the post-restoration changes in soil morphology, and that these changes correspond to patterns of vascular plant diversity. Soil diversity and dynamism increased 5 yr after the restoration, but some typical soils of braided rivers were still missing. Soil typicality and dynamism were correlated to vegetation changes. These results suggest a limited success of the project, in agreement with evaluations carried out at the same site using other, more resource-demanding, methods (e.g., soil fauna, fish diversity, ecosystem functioning). Soil morphology provides structural and functional information on floodplain ecosystems. The spatio-temporal heterogeneity of soil morphology represents a cost-efficient ecological indicator that could easily be integrated into rapid assessment protocols of floodplain and river restoration projects. The follow-up assessment after several major floods (≥ HQ20) should take place to allow for testing the longer-term validity of our conclusion for the River Thur site. More generally, it would be useful to apply the soil morphology indicator approach in different settings to test its broader applicability.

[Regional ecological planning and ecological network construction: a case study of "Ji Triangle" Region].

Science.gov (United States)

Li, Bo; Han, Zeng-Lin; Tong, Lian-Jun

2009-05-01

By the methods of in situ investigation and regional ecological planning, the present ecological environment, ecosystem vulnerability, and ecological environment sensitivity in "Ji Triangle" Region were analyzed, and the ecological network of the study area was constructed. According to the ecological resources abundance degree, ecological recovery, farmland windbreak system, environmental carrying capacity, forestry foundation, and ecosystem integrity, the study area was classified into three regional ecological function ecosystems, i. e., east low hill ecosystem, middle plain ecosystem, and west plain wetland ecosystem. On the basis of marking regional ecological nodes, the regional ecological corridor (Haerbin-Dalian regional axis, Changchun-Jilin, Changchun-Songyuan, Jilin-Songyuan, Jilin-Siping, and Songyuan-Siping transportation corridor) and regional ecological network (one ring, three links, and three belts) were constructed. Taking the requests of regional ecological security into consideration, the ecological environment security system of "Ji Triangle" Region, including regional ecological conservation district, regional ecological restored district, and regional ecological management district, was built.

Civic Ecology: A Postmodern Approach to Ecological Sustainability

Science.gov (United States)

Lopes, V. L.

2013-12-01

Human agency is transforming the planetary processes at unprecedented rates risking damaging essential life-support systems. Climate change, massive species extinction, land degradation, resources depletion, overpopulation, poverty and social injustice are all the result of human choices and non-sustainable ways of life. The survival of our modern economic systems depends upon insatiable consumption - a simple way of life no longer satisfies most people. Detached, instrumental rationality has created an ideal of liberalism based on individual pursuit of self-interest, leading the way into unprecedented material progress but bringing with it human alienation, social injustice, and ecological degradation. The purpose of this presentation is to introduce a community-based systems response to a growing sense that the interlocked social-ecological crisis is as much a problem of human thought and behavior as it is about identifying carrying capacities and CO2 concentrations in the atmosphere. This approach, referred to here as civic ecology, presents a new and important paradigm shift in sustainability practice that attempts to bring together and integrate ecological ideas and postmodern thinking. As such, it is as much a holistic, dynamic, and synergistic approach to ecological sustainability, as it is a philosophy of life and ethical perspective born of ecological understanding and insight. Civic ecology starts with the proposition that the key factor determining the health of the ecosphere is the behavior of human beings, and therefore many of the most important issues related to sustainability lie in the areas of human thought and culture. Thus, the quest for sustainability must include as a central concern the transformation of psychological and behavioral patterns that have become an imminent danger to planetary health. At the core of this understanding is a fundamental paradigm shift from the basic commitments of modern Western culture to its model of mechanism

Adaptive landscape and functional diversity of Neotropical cichlids: implications for the ecology and evolution of Cichlinae (Cichlidae; Cichliformes).

Science.gov (United States)

Arbour, J H; López-Fernández, H

2014-11-01

Morphological, lineage and ecological diversity can vary substantially even among closely related lineages. Factors that influence morphological diversification, especially in functionally relevant traits, can help to explain the modern distribution of disparity across phylogenies and communities. Multivariate axes of feeding functional morphology from 75 species of Neotropical cichlid and a stepwise-AIC algorithm were used to estimate the adaptive landscape of functional morphospace in Cichlinae. Adaptive landscape complexity and convergence, as well as the functional diversity of Cichlinae, were compared with expectations under null evolutionary models. Neotropical cichlid feeding function varied primarily between traits associated with ram feeding vs. suction feeding/biting and secondarily with oral jaw muscle size and pharyngeal crushing capacity. The number of changes in selective regimes and the amount of convergence between lineages was higher than expected under a null model of evolution, but convergence was not higher than expected under a similarly complex adaptive landscape. Functional disparity was compatible with an adaptive landscape model, whereas the distribution of evolutionary change through morphospace corresponded with a process of evolution towards a single adaptive peak. The continentally distributed Neotropical cichlids have evolved relatively rapidly towards a number of adaptive peaks in functional trait space. Selection in Cichlinae functional morphospace is more complex than expected under null evolutionary models. The complexity of selective constraints in feeding morphology has likely been a significant contributor to the diversity of feeding ecology in this clade. © 2014 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

The survey of ecologically acceptable flows in Slovenia

Science.gov (United States)

Smolar-Žvanut, Nataša; Burja, Darko

2008-11-01

Excessive water abstractions from watercourses constitute a negative impact on the structure and functioning of aquatic and riparian ecosystems. In order to preserve and improve the aquatic ecosystems it is therefore necessary to maintain adequate quantity and quality of water in watercourses, which can be ensured by providing ecologically acceptable flow (EAF). In Slovenia, a large diversity of watercourses regarding their hydrologic, morphological and ecological characteristics dictates the determination of EAF separately for individual sections of watercourses. Since 1994, the determination of EAF in Slovenia has been carried out primarily for the existing water abstractions such as hydroelectric power plants, fish farms, and to a lesser extent for the abstractions for drinking water, process water, recreation facilities and at the outflows from reservoirs. The results of EAF value analyses showed that the EAF values for individual water abstractions differed widely both with respect to the values of the mean annual minimum flow and the values of the mean daily flow. The results of analyses support the basis for the determination of EAF used in most EU countries, namely that EAF must be determined through interdisciplinary approach where the hydrologic data represent the benchmark values for the determination of EAF.

The survey of ecologically acceptable flows in Slovenia

International Nuclear Information System (INIS)

Smolar-Zvanut, Natasa; Burja, Darko

2008-01-01

Excessive water abstractions from watercourses constitute a negative impact on the structure and functioning of aquatic and riparian ecosystems. In order to preserve and improve the aquatic ecosystems it is therefore necessary to maintain adequate quantity and quality of water in watercourses, which can be ensured by providing ecologically acceptable flow (EAF). In Slovenia, a large diversity of watercourses regarding their hydrologic, morphological and ecological characteristics dictates the determination of EAF separately for individual sections of watercourses. Since 1994, the determination of EAF in Slovenia has been carried out primarily for the existing water abstractions such as hydroelectric power plants, fish farms, and to a lesser extent for the abstractions for drinking water, process water, recreation facilities and at the outflows from reservoirs. The results of EAF value analyses showed that the EAF values for individual water abstractions differed widely both with respect to the values of the mean annual minimum flow and the values of the mean daily flow. The results of analyses support the basis for the determination of EAF used in most EU countries, namely that EAF must be determined through interdisciplinary approach where the hydrologic data represent the benchmark values for the determination of EAF.

Introduction to the Special Volume on "Ecology and Ecological Modeling in R"

OpenAIRE

Kneib, Thomas; Petzoldt, Thomas

2007-01-01

The third special volume in the "Foometrics in R" series of the Journal of Statistical Software collects a number of contributions describing statistical methodology and corresponding implementations related to ecology and ecological modelling. The scope of the papers ranges from theoretical ecology and ecological modelling to statistical methodology relevant for data analyses in ecological applications.

Morphological Characteristics of Au Films Deposited on Ti: A Combined SEM-AFM Study

Directory of Open Access Journals (Sweden)

Francesco Ruffino

2018-03-01

Full Text Available Deposited Au films and coatings are, nowadays, routinely used as active or passive elements in several innovative electronic, optoelectronic, sensing, and energy devices. In these devices, the physical properties of the Au films are strongly determined by the films nanoscale structure. In addition, in these devices, often, a layer of Ti is employed to promote adhesion and, so, influencing the nanoscale structure of the deposited Au film. In this work, we present experimental analysis on the nanoscale cross-section and surface morphology of Au films deposited on Ti. In particular, we sputter-deposited thick (>100 nm thickness Au films on Ti foils and we used Scanning Electron Microscopy to analyze the films cross-sectional and surface morphology as a function of the Au film thickness and deposition angle. In addition, we analyzed the Au films surface morphology by Atomic Force Microscopy which allowed quantifying the films surface roughness versus the film thickness and deposition angle. The results establish a relation between the Au films cross-sectional and surface morphologies and surface roughness to the film thickness and deposition angle. These results allow setting a general working framework to obtain Au films on Ti with specific morphological and topographic properties for desired applications in which the Ti adhesion layer is needed for Au.

Interaction networks, ecological stability, and collective antibiotic tolerance in polymicrobial infections

Science.gov (United States)

de Vos, Marjon G. J.; Bollenbach, Tobias

2017-01-01

Polymicrobial infections constitute small ecosystems that accommodate several bacterial species. Commonly, these bacteria are investigated in isolation. However, it is unknown to what extent the isolates interact and whether their interactions alter bacterial growth and ecosystem resilience in the presence and absence of antibiotics. We quantified the complete ecological interaction network for 72 bacterial isolates collected from 23 individuals diagnosed with polymicrobial urinary tract infections and found that most interactions cluster based on evolutionary relatedness. Statistical network analysis revealed that competitive and cooperative reciprocal interactions are enriched in the global network, while cooperative interactions are depleted in the individual host community networks. A population dynamics model parameterized by our measurements suggests that interactions restrict community stability, explaining the observed species diversity of these communities. We further show that the clinical isolates frequently protect each other from clinically relevant antibiotics. Together, these results highlight that ecological interactions are crucial for the growth and survival of bacteria in polymicrobial infection communities and affect their assembly and resilience. PMID:28923953

Neural basis for generalized quantifier comprehension.

Science.gov (United States)

McMillan, Corey T; Clark, Robin; Moore, Peachie; Devita, Christian; Grossman, Murray

2005-01-01

Generalized quantifiers like "all cars" are semantically well understood, yet we know little about their neural representation. Our model of quantifier processing includes a numerosity device, operations that combine number elements and working memory. Semantic theory posits two types of quantifiers: first-order quantifiers identify a number state (e.g. "at least 3") and higher-order quantifiers additionally require maintaining a number state actively in working memory for comparison with another state (e.g. "less than half"). We used BOLD fMRI to test the hypothesis that all quantifiers recruit inferior parietal cortex associated with numerosity, while only higher-order quantifiers recruit prefrontal cortex associated with executive resources like working memory. Our findings showed that first-order and higher-order quantifiers both recruit right inferior parietal cortex, suggesting that a numerosity component contributes to quantifier comprehension. Moreover, only probes of higher-order quantifiers recruited right dorsolateral prefrontal cortex, suggesting involvement of executive resources like working memory. We also observed activation of thalamus and anterior cingulate that may be associated with selective attention. Our findings are consistent with a large-scale neural network centered in frontal and parietal cortex that supports comprehension of generalized quantifiers.

A hyper-temporal remote sensing protocol for high-resolution mapping of ecological sites.

Science.gov (United States)

Maynard, Jonathan J; Karl, Jason W

2017-01-01

Ecological site classification has emerged as a highly effective land management framework, but its utility at a regional scale has been limited due to the spatial ambiguity of ecological site locations in the U.S. or the absence of ecological site maps in other regions of the world. In response to these shortcomings, this study evaluated the use of hyper-temporal remote sensing (i.e., hundreds of images) for high spatial resolution mapping of ecological sites. We posit that hyper-temporal remote sensing can provide novel insights into the spatial variability of ecological sites by quantifying the temporal response of land surface spectral properties. This temporal response provides a spectral 'fingerprint' of the soil-vegetation-climate relationship which is central to the concept of ecological sites. Consequently, the main objective of this study was to predict the spatial distribution of ecological sites in a semi-arid rangeland using a 28-year time series of normalized difference vegetation index from Landsat TM 5 data and modeled using support vector machine classification. Results from this study show that support vector machine classification using hyper-temporal remote sensing imagery was effective in modeling ecological site classes, with a 62% correct classification. These results were compared to Gridded Soil Survey Geographic database and expert delineated maps of ecological sites which had a 51 and 89% correct classification, respectively. An analysis of the effects of ecological state on ecological site misclassifications revealed that sites in degraded states (e.g., shrub-dominated/shrubland and bare/annuals) had a higher rate of misclassification due to their close spectral similarity with other ecological sites. This study identified three important factors that need to be addressed to improve future model predictions: 1) sampling designs need to fully represent the range of both within class (i.e., states) and between class (i.e., ecological sites

Importance and Use of Morphological Characteristics of Blackberry (Vaccinium corymbosum L. in the Course of DUS

Directory of Open Access Journals (Sweden)

Л. І. Улич

2011-07-01

Full Text Available The article offers results of research on morphological characteristics and biological properties of blackberry, their inheritance, as well as stability and variability under the influence of agro-ecological conditions and stress factors of the environment with a view of recognizing, describing and identifying varieties undergoing official research and technical examination on DUS, which also could be used in the breeding process.

Predictors for reproductive isolation in a ring species complex following genetic and ecological divergence.

Science.gov (United States)

Pereira, Ricardo J; Monahan, William B; Wake, David B

2011-07-06

Reproductive isolation (RI) is widely accepted as an important "check point" in the diversification process, since it defines irreversible evolutionary trajectories. Much less consensus exists about the processes that might drive RI. Here, we employ a formal quantitative analysis of genetic interactions at several stages of divergence within the ring species complex Ensatina eschscholtzii in order to assess the relative contribution of genetic and ecological divergence for the development of RI. By augmenting previous genetic datasets and adding new ecological data, we quantify levels of genetic and ecological divergence between populations and test how they correlate with a restriction of genetic admixture upon secondary contact. Our results indicate that the isolated effect of ecological divergence between parental populations does not result in reproductively isolated taxa, even when genetic transitions between parental taxa are narrow. Instead, processes associated with overall genetic divergence are the best predictors of reproductive isolation, and when parental taxa diverge in nuclear markers we observe a complete cessation of hybridization, even to sympatric occurrence of distinct evolutionary lineages. Although every parental population has diverged in mitochondrial DNA, its degree of divergence does not predict the extent of RI. These results show that in Ensatina, the evolutionary outcomes of ecological divergence differ from those of genetic divergence. While evident properties of taxa may emerge via ecological divergence, such as adaptation to local environment, RI is likely to be a byproduct of processes that contribute to overall genetic divergence, such as time in geographic isolation, rather than being a direct outcome of local adaptation.

Incorporating the Spatial Road Disturbance Index (SPROADI in Ecological Impacts Assessment of Roads at Landscape Scale (Case study: Eastern Part of Isfahan Province

Directory of Open Access Journals (Sweden)

Sh. Nematollahi

2017-06-01

Full Text Available Development of roads can have deleterious effects on natural habitats containing species of conservation concern. Fragmentation of habitat into small, non-contiguous patches may result in dramatic population declines. Thus appropriate studies quantifying ecological impacts of roads at landscape scale are essential. In this study, the Spatial Road Disturbance Index (SPROADI was applied for the ecological impact assessment of the roads network in Eastern part of Isfahan Province, including Abassabad wildlife refuge and Siahkouh National park, which are among the most important habitats for Asiatic Cheetah (Acinonyx jubatus venaticus classified as Critically Endangered (CR on the IUCN Red List. This new landscape index uses three sub-indices including traffic intensity, vicinity impact and fragmentation grade to calculate the ecological impacts of roads network. Results obtained through quantifying the Spatial Road Disturbance Index showed that the degree of disturbance by roads network is between 0 and 54.53. Our results also revealed that 12 percent of Abassabad wildlife refuge and wide range of suitable habitats for Asiatic Cheetah were affected by roads network, which presents a conservation concern for this critically endangered species.

Integrating human and machine intelligence in galaxy morphology classification tasks

Science.gov (United States)

Beck, Melanie R.; Scarlata, Claudia; Fortson, Lucy F.; Lintott, Chris J.; Simmons, B. D.; Galloway, Melanie A.; Willett, Kyle W.; Dickinson, Hugh; Masters, Karen L.; Marshall, Philip J.; Wright, Darryl

2018-06-01

Quantifying galaxy morphology is a challenging yet scientifically rewarding task. As the scale of data continues to increase with upcoming surveys, traditional classification methods will struggle to handle the load. We present a solution through an integration of visual and automated classifications, preserving the best features of both human and machine. We demonstrate the effectiveness of such a system through a re-analysis of visual galaxy morphology classifications collected during the Galaxy Zoo 2 (GZ2) project. We reprocess the top-level question of the GZ2 decision tree with a Bayesian classification aggregation algorithm dubbed SWAP, originally developed for the Space Warps gravitational lens project. Through a simple binary classification scheme, we increase the classification rate nearly 5-fold classifying 226 124 galaxies in 92 d of GZ2 project time while reproducing labels derived from GZ2 classification data with 95.7 per cent accuracy. We next combine this with a Random Forest machine learning algorithm that learns on a suite of non-parametric morphology indicators widely used for automated morphologies. We develop a decision engine that delegates tasks between human and machine and demonstrate that the combined system provides at least a factor of 8 increase in the classification rate, classifying 210 803 galaxies in just 32 d of GZ2 project time with 93.1 per cent accuracy. As the Random Forest algorithm requires a minimal amount of computational cost, this result has important implications for galaxy morphology identification tasks in the era of Euclid and other large-scale surveys.

Elaiophores: their taxonomic distribution, morphology and functions

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Clivia Carolina Fiorilo Possobom

Full Text Available ABSTRACT Elaiophores are floral glands that secrete non-volatile oils as a reward for their pollinators. Their secretions mediate a specialized interaction between oil-producing plants and a few species of oil-collecting bees - Apidae and Melittidae. The present review focuses on the morphological and functional aspects of these secretory structures. We also provide information on their chemistry and pollination ecology. Our survey is organized taxonomically among the plant families for which elaiophore occurrence has been confirmed -for the monocots, Iridaceae and Orchidaceae, and for the eudicots, Calceolariaceae, Cucurbitaceae, Krameriaceae, Malpighiaceae, Plantaginaceae, Primulaceae, Scrophulariaceae, Solanaceae and Stilbaceae. Most oil flowers are zygomorphic, bisexual, nectarless and present their elaiophores on the protective whorls or on the androecium. Trichomal elaiophores are reported in all of these families except Krameriaceae and Malpighiaceae, and they vary in the density and morphology of the trichomes. Epithelial elaiophores occur in some monocot representatives and in Krameriaceae and Malpighiaceae, and are similar among species. An intermediate type of elaiophore is reported in some species of Orchidaceae. Regardless of elaiophore type, these glands have similar subcellular features and secretion-release mechanisms. Finally, we note the dearth of information on elaiophore ultrastructure and functioning for several plant families.

[Ecological carrying capacity and Chongming Island's ecological construction].

Science.gov (United States)

Wang, Kaiyun; Zou, Chunjing; Kong, Zhenghong; Wang, Tianhou; Chen, Xiaoyong

2005-12-01

This paper overviewed the goals of Chongming Island's ecological construction and its background, analyzed the current eco-economic status and constraints of the Island, and put forward some scientific issues on its ecological construction. It was suggested that for the resources-saving and sustainable development of the Island, the researches on its ecological construction should be based on its ecological carrying capacity, fully take the regional characteristics into consideration, and refer the successful development modes at home and abroad. The carrying capacity study should ground on systemic and dynamic views, give a thorough evaluation of the Island's present carrying capacity, simulate its possible changes, and forecast its demands and risks. Operable countermeasures to promote the Island's carrying capacity should be worked out, new industry structure, population scale, and optimized distribution projects conforming to regional carrying capacity should be formulated, and effective ecological security alarming and control system should be built, with the aim of providing suggestions and strategic evidences for the decision-making of economic development and sustainable environmental resources use of the region.

The ecological impacts of marine debris: unraveling the demonstrated evidence from what is perceived.

Science.gov (United States)

Rochman, Chelsea M; Browne, Mark Anthony; Underwood, A J; van Franeker, Jan A; Thompson, Richard C; Amaral-Zettler, Linda A

2016-02-01

Anthropogenic debris contaminates marine habitats globally, leading to several perceived ecological impacts. Here, we critically and systematically review the literature regarding impacts of debris from several scientific fields to understand the weight of evidence regarding the ecological impacts of marine debris. We quantified perceived and demonstrated impacts across several levels of biological organization that make up the ecosystem and found 366 perceived threats of debris across all levels. Two hundred and ninety-six of these perceived threats were tested, 83% of which were demonstrated. The majority (82%) of demonstrated impacts were due to plastic, relative to other materials (e.g., metals, glass) and largely (89%) at suborganismal levels (e.g., molecular, cellular, tissue). The remaining impacts, demonstrated at higher levels of organization (i.e., death to individual organisms, changes in assemblages), were largely due to plastic marine debris (> 1 mm; e.g., rope, straws, and fragments). Thus, we show evidence of ecological impacts from marine debris, but conclude that the quantity and quality of research requires improvement to allow the risk of ecological impacts of marine debris to be determined with precision. Still, our systematic review suggests that sufficient evidence exists for decision makers to begin to mitigate problematic plastic debris now, to avoid risk of irreversible harm.

Hybridization Associated with Cycles of Ecological Succession in a Passerine Bird.

Science.gov (United States)

Duckworth, Renée A; Semenov, Georgy A

2017-10-01

Identifying the diversity of contexts that can lead to hybridization is important for understanding its prevalence and dynamics in natural populations. Despite the potential of ecological succession to dramatically alter species co-occurrence and abundances, it is unknown whether it directly promotes hybridization and, if so, has long-lasting consequences. Here, we summarize 30 years of survey data across 10 populations to show that in western and mountain bluebirds, heterospecific pairing occurs during repeatable and transient colonization events at the early stages of species turnover. Despite mixed pairing occurring only during early succession, genetic data showed presence of hybrids at both early and late successional stages. Moreover, hybrids showed novel patterns of variation in morphology and behavior, emphasizing that even ephemeral contexts for hybridization can have important evolutionary consequences. Our results suggest that because ecological succession often brings together closely related competitors in disparate numbers but lasts for only a brief period of time, it may be a widespread but underappreciated context for hybridization.

Philosophy of ecology

CERN Document Server

Brown, Bryson; Peacock, Kent A

2011-01-01

The most pressing problems facing humanity today - over-population, energy shortages, climate change, soil erosion, species extinctions, the risk of epidemic disease, the threat of warfare that could destroy all the hard-won gains of civilization, and even the recent fibrillations of the stock market - are all ecological or have a large ecological component. in this volume philosophers turn their attention to understanding the science of ecology and its huge implications for the human project. To get the application of ecology to policy or other practical concerns right, humanity needs a clear and disinterested philosophical understanding of ecology which can help identify the practical lessons of science. Conversely, the urgent practical demands humanity faces today cannot help but direct scientific and philosophical investigation toward the basis of those ecological challenges that threaten human survival. This book will help to fuel the timely renaissance of interest in philosophy of ecology that is now oc...

The morphological signs of plants of white cabbage (Brassica oleraceae L. convar. capitata (L. Alef. var. alba DC and their variability depending on type of sort

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О. Я. Жук

2008-04-01

Full Text Available Indicators of the morphological signs of type of sort on white cabbage plants Dutch flat, Belarus, Amager, Langendijker winter and their variability are the presented. It is established low and average factor of a variation at the majority of the morphological signs. Strong high-quality and ecological variability of signs “height external rake” and “its size leafy parts” at type of sort Dutch flat is defined.

Cranial and mandibular shape variation in the genus Carollia (Mammalia: Chiroptera from Colombia: biogeographic patterns and morphological modularity

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Camilo López-Aguirre

2015-08-01

Full Text Available Neotropical bats of the genus Carollia are widely studied due to their abundance, distribution and relevance for ecosystems. However, the ecomorphological boundaries of these species are poorly differentiated, and consequently correspondence between their geographic distribution, ecological plasticity and morphological variation remains unclear. In this study, patterns of cranial and mandibular morphological variation were assessed for Carollia brevicauda, C. castanea and C. perspicillata from Colombia. Using geometric morphometrics, morphological variation was examined with respect to: differences in intraspecific variation, morphological modularity and integration, and biogeographic patterns. Patterns of intraspecific variation were different for each species in both cranial and mandibular morphology, with functional differences apparent according to diet. Cranial modularity varied between species whereas mandibular modularity did not. High cranial and mandibular correlation reflects Cranium-Mandible integration as a functional unit. Similarity between the biogeographic patterns in C. brevicauda and C. perspicillata indicates that the Andes do not act as a barrier but rather as an independent region, isolating the morphology of Andean populations of larger-bodied species. The biogeographic pattern for C. castanea was not associated with the physiography of the Andes, suggesting that large body size does not benefit C. brevicauda and C. perspicillata in maintaining homogeneous morphologies among populations.

Cranial and mandibular shape variation in the genus Carollia (Mammalia: Chiroptera) from Colombia: biogeographic patterns and morphological modularity.

Science.gov (United States)

López-Aguirre, Camilo; Pérez-Torres, Jairo; Wilson, Laura A B

2015-01-01

Neotropical bats of the genus Carollia are widely studied due to their abundance, distribution and relevance for ecosystems. However, the ecomorphological boundaries of these species are poorly differentiated, and consequently correspondence between their geographic distribution, ecological plasticity and morphological variation remains unclear. In this study, patterns of cranial and mandibular morphological variation were assessed for Carollia brevicauda, C. castanea and C. perspicillata from Colombia. Using geometric morphometrics, morphological variation was examined with respect to: differences in intraspecific variation, morphological modularity and integration, and biogeographic patterns. Patterns of intraspecific variation were different for each species in both cranial and mandibular morphology, with functional differences apparent according to diet. Cranial modularity varied between species whereas mandibular modularity did not. High cranial and mandibular correlation reflects Cranium-Mandible integration as a functional unit. Similarity between the biogeographic patterns in C. brevicauda and C. perspicillata indicates that the Andes do not act as a barrier but rather as an independent region, isolating the morphology of Andean populations of larger-bodied species. The biogeographic pattern for C. castanea was not associated with the physiography of the Andes, suggesting that large body size does not benefit C. brevicauda and C. perspicillata in maintaining homogeneous morphologies among populations.

World-Ecology and Ireland: The Neoliberal Ecological Regime

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Sharae Deckard

2016-03-01

Full Text Available Since the collapse of the Celtic Tiger, the socio-economic particularity of neoliberal capitalism in its Irish manifestation has increasingly been critiqued, but little attention has been paid to neoliberalism as ecology within Ireland. This article conducts an exploratory survey of the characteristics of the Irish neoliberal ecological regime during and after the Celtic Tiger, identifying the opening of new commodity frontiers (such as fracking, water, agro-biotechnology, and biopharma constituted in the neoliberal drive to appropriate and financialize nature. I argue for the usefulness of applying not only the tools of world-systems analysis, but also Jason W. Moore’s world-ecological paradigm, to analysis of Ireland as a semi-periphery. What is crucial to a macro-ecological understanding of Ireland’s role in the neoliberal regime of the world-ecology is the inextricability of its financial role as a tax haven and secrecy jurisdiction zone from its environmental function as a semi-peripheral pollution and water haven. We can adapt Jason W. Moore’s slogan that “Wall Street…becomes a way of organizing all of nature, characterized by the financialization of any income-generating activity” (Moore 2011b: 39 to say that to say that the “IFSC is a way of organizing nature,” with pernicious consequences for water, energy, and food systems in Ireland. Financial service centers and pharmaceutical factories, plantations and cattle ranches, tax havens and pollution havens, empires and common markets are all forms of environment-making that constellate human relations and extra-human processes into new ecological regimes. More expansive, dialectical understandings of “ecology” as comprising the whole of socio-ecological relations within the capitalist world-ecology—from farming to pharma to financialization—are crucial to forming configurations of knowledge able not only to take account of Ireland’s role in the environmental

Hydrology and Ecology Go to Court

Science.gov (United States)

Wise, W. R.; Crisman, T. L.

2009-04-01

historical data from which to quantify the flow regime. Nevertheless, the authors worked with their legal team to fill in the blanks based on their knowledge of hydrology and ecology. One of the most important lessons learned by the authors is the importance of participating in the public process. Often, scientists shy away from such matters. Many of the principles that were applied were researched long ago. No research papers were generated by the case, but many were used to solidify arguments. It was gratifying to the authors to realize that the work product of their disciplines could be applied in a cooperative manner to address an issue with such profound implications. It was a clear demonstration that ecohydrology, the linkage of hydrology and ecology, was much preferred as a way to address a complicated legal issue.

Community variability and ecological functioning: 40 years of change in the North Sea benthos.

Science.gov (United States)

Clare, D S; Robinson, L A; Frid, C L J

2015-06-01

Using established associations between species traits (life history, morphological and behavioural characteristics) and key ecological functions, we applied biological traits analysis (BTA) to investigate the consequences of 40 years of change in two North Sea benthic communities. Ecological functioning (trait composition) was found to be statistically indistinguishable across periods that differed significantly in taxonomic composition. A temporary alteration to functioning was, however, inferred at both sampling stations; coinciding with the North Sea regime shift of the 1980s. Trait composition recovered after 1 year at the station located inside the grounds of a trawl fishery, whereas the station located outside the main area of fishing activity underwent a six-year period of significantly altered, and temporally unstable, trait composition. A further alteration to functioning was inferred at the fished station, when the population of a newly established species rapidly increased in numbers. The results suggest that density compensation by characteristically similar (redundant) taxa acts to buffer changes to ecological functioning over time, but that functional stability is subject to aperiodic disruption due to substitutions of dissimilar taxa or uncompensated population fluctuations. The rate at which ecological functioning stabilises and recovers appears to be dependent on environmental context; e.g. disturbance regime. Copyright © 2015 Elsevier Ltd. All rights reserved.

Ecological and general systems an introduction to systems ecology

CERN Document Server

Odum, Howard T.

1994-01-01

Using an energy systems language that combines energetics, kinetics, information, cybernetics, and simulation, Ecological and General Systems compares models of many fields of science, helping to derive general systems principles. First published as Systems Ecology in 1983, Ecological and General Systems proposes principles of self-organization and the designs that prevail by maximizing power and efficiency. Comparisons to fifty other systems languages are provided. Innovative presentations are given on earth homeostasis (Gaia); the inadequacy of presenting equations without network relationships and energy constraints; the alternative interpretation of high entropy complexity as adaptive structure; basic equations of ecological economics; and the energy basis of scientific hierarchy.

Ecological Regime Shifts in Lake Kälksjön, Sweden, in Response to Abrupt Climate Change Around the 8.2 ka Cooling Event

DEFF Research Database (Denmark)

Randsalu-Wendrup, L.; Conley, D.J.; Snowball, I.

2012-01-01

. This study demonstrates that it is possible to detect, quantify and test for regime shifts in paleoecological data, and it highlights the need for high sampling resolution and precise chronological control. High-resolution paleoecological reconstructions of ecological regime shifts in response to climate...

Hydrologic connectivity affects fish assemblage structure, diversity, and ecological traits in the unregulated Gambia River, West Africa

Czech Academy of Sciences Publication Activity Database

White, Seth M.; Ondračková, Markéta; Reichard, Martin

2012-01-01

Roč. 44, č. 4 (2012), s. 521-530 ISSN 0006-3606 R&D Projects: GA AV ČR IAA6093404 Institutional research plan: CEZ:AV0Z60930519 Institutional support: RVO:68081766 Keywords : fish assemblage * functional morphology * large tropical river s * lateral migration * multivariate analysis * pre-impoundment * reference condition * trophic position Subject RIV: EH - Ecology, Behaviour Impact factor: 2.351, year: 2012

Exposing ecological and economic costs of the research-implementation gap and compromises in decision making.

Science.gov (United States)

Kareksela, Santtu; Moilanen, Atte; Ristaniemi, Olli; Välivaara, Reima; Kotiaho, Janne S

2018-02-01

The frequently discussed gap between conservation science and practice is manifest in the gap between spatial conservation prioritization plans and their implementation. We analyzed the research-implementation gap of one zoning case by comparing results of a spatial prioritization analysis aimed at avoiding ecological impact of peat mining in a regional zoning process with the final zoning plan. We examined the relatively complex planning process to determine the gaps among research, zoning, and decision making. We quantified the ecological costs of the differing trade-offs between ecological and socioeconomic factors included in the different zoning suggestions by comparing the landscape-level loss of ecological features (species occurrences, habitat area, etc.) between the different solutions for spatial allocation of peat mining. We also discussed with the scientists and planners the reasons for differing zoning suggestions. The implemented plan differed from the scientists suggestion in that its focus was individual ecological features rather than all the ecological features for which there were data; planners and decision makers considered effects of peat mining on areas not included in the prioritization analysis; zoning was not truly seen as a resource-allocation process and not emphasized in general minimizing ecological losses while satisfying economic needs (peat-mining potential); and decision makers based their prioritization of sites on site-level information showing high ecological value and on single legislative factors instead of finding a cost-effective landscape-level solution. We believe that if the zoning and decision-making processes are very complex, then the usefulness of science-based prioritization tools is likely to be reduced. Nevertheless, we found that high-end tools were useful in clearly exposing trade-offs between conservation and resource utilization. © 2017 Society for Conservation Biology.

Designing ecological flows to gravely braided rivers in alpine environments

Science.gov (United States)

Egozi, R.; Ashmore, P.

2009-04-01

Designing ecological flows in gravelly braided streams requires estimating the channel forming discharge in order to maintain the braided reach physical (allocation of flow and bed load) and ecological (maintaining the habitat diversity) functions. At present, compared to single meander streams, there are fewer guiding principles for river practitioners that can be used to manage braided streams. Insight into braiding morphodynamics using braiding intensity indices allows estimation of channel forming discharge. We assess variation in braiding intensity by mapping the total number of channels (BIT) and the number of active (transporting bed load) channels (BIA) at different stages of typical diurnal melt-water hydrographs in a pro-glacial braided river, Sunwapta River, Canada. Results show that both BIA and BIT vary with flow stage but over a limited range of values. Furthermore, maximum BIT occurs below peak discharge. At this stage there is a balance between channel merging from inundation and occupation of new channels as the stage rises. This stage is the channel forming discharge because above this stage the existing braided pattern cannot discharge the volume of water without causing morphological changes (e.g., destruction of bifurcations, channel avulsion). Estimation of the channel forming discharge requires a set of braiding intensity measurements over a range of flow stages. The design of ecological flows must take into consideration flow regime characteristics rather than just the channel forming discharge magnitude.

Ecological security pattern construction based on ecological protection redlines in China

Science.gov (United States)

Zou, Changxin

2017-04-01

China is facing huge environmental problems with its current rapid rate of urbanization and industrialization, thus causing biodiversity loss, ecosystem service degradation on a major scale. Against this background, three previous examples (the nature reserve policy, the afforestation policy, and the zoning policy) are implemented in China. These all play important roles in protecting natural ecosystems, although they can sometimes cause new problems and lack rigorous targets for environmental outcomes. To overcome current management conflicts, China has proposed a new "ecological protection redlines" policy (EPR). EPR can be defined as the ecological baseline area needed to provide ecosystem services to guarantee and maintain ecological safety. This study analyzed the scope, objectives and technical methods of delineating EPR in China, and put forward the proposed scheme for the ecological security pattern based on EPR. We constructed three kinds of redlines in China, including key ecological function area redlines, ecological sensitive or fragile areas redlines, and forbidden development areas redlines. For the key ecological function area redlines, a total of 38 water conservation functional zones have been designated, covering a total area of 3.23 million km2; 14 soil conservation zones have been designated, covering a total area of 881700 km2; wind-prevention and sand-fixation zones across the country cover a total area of about 1.73 million km2, accounting for 57.13% of the total land area of the whole country. With respect to the ecologically vulnerable redlines, 18 ecologically vulnerable zones has been designated across the country, covering 2.19 million km2, accounting for 22.86% of the total land area of the whole country. Forbidden development areas redlines covered a total area of 3.29 million km2, accounting for 34.3% of the total land area of the whole country. We also suggest to form a complete ecological security pattern including patterns of

Ecology

International Nuclear Information System (INIS)

Kalusche, D.

1978-01-01

The book turns to the freshment, the teacher, for preparation of ecological topics for lessons, but also to pupils of the secondary stage II, and the main course ecology. The book was knowingly held simple with the restriction to: the ecosystem and its abiotic basic functions, simple articles on population biology, bioceonotic balance ith the questions of niche formation and the life form types coherent with it, of the substance and energy household, the production biology and space-wise and time-wise differentations within an ecological system form the main points. A central role in the volume is given to the illustrations. Their variety is to show and deepen the coherences shown. (orig./HP) [de

Ecological risk assessment of hydropower dam construction based on ecological network analysis

OpenAIRE

Chen, Shaoqing; Fath, Brian D.; Chen, Bin

2010-01-01

Dam construction is regarded as one of the major factors contributing to significant modifications of the river ecosystems, and the ecological risk (ER) assessment of dam construction has received growing attention in recent years. In the present study, we explored the potential ecological risk caused by dam project based on the general principles of the ecological risk assessment. Ecological network analysis was proposed as the usable analytic method for the implement of ecological risk asse...

Ecological niche comparison and molecular phylogeny segregate the invasive moss species Campylopus introflexus (Leucobryaceae, Bryophyta) from its closest relatives.

Science.gov (United States)

Gama, Renato; Aguirre-Gutiérrez, Jesús; Stech, Michael

2017-10-01

The delimitation of the invasive moss species Campylopus introflexus from its closest relative, Campylopus pilifer , has been long debated based on morphology. Previous molecular phylogenetic reconstructions based on the nuclear ribosomal internal transcribed spacers (ITS) 1 and 2 showed that C. pilifer is split into an Old World and a New World lineage, but remained partly inconclusive concerning the relationships between these two clades and C. introflexus . Analyses of an extended ITS dataset displayed statistically supported incongruence between ITS1 and ITS2. ITS1 separates the New World clade of C. pilifer from a clade comprising C. introflexus and the Old World C. pilifer . Ancestral state reconstruction showed that this topology is morphologically supported by differences in the height of the dorsal costal lamellae in leaf cross-section (despite some overlap). ITS2, in contrast, supports the current morphological species concept, i.e., separating C. introflexus from C. pilifer , which is morphologically supported by the orientation of the hyaline hair point at leaf apex as well as costal lamellae height. Re-analysis of published and newly generated plastid atpB-rbcL spacer sequences supported the three ITS lineages. Ecological niche modeling proved a useful approach and showed that all three molecular lineages occupy distinct environmental spaces that are similar, but undoubtedly not equivalent. In line with the ITS1 topology, the C. pilifer lineage from the New World occupies the most distinct environmental niche, whereas the niches of Old World C. pilifer and C. introflexus are very similar. Taking the inferences from ecological niche comparisons, phylogenetics, and morphology together, we conclude that all three molecular lineages represent different taxa that should be recognized as independent species, viz. C. introflexus , C. pilifer (Old World clade), and the reinstated C. lamellatus Mont. (New World clade).

Discordance between morphological and molecular species boundaries among Caribbean species of the reef sponge Callyspongia

OpenAIRE

DeBiasse, Melissa B; Hellberg, Michael E

2015-01-01

Sponges are among the most species-rich and ecologically important taxa on coral reefs, yet documenting their diversity is difficult due to the simplicity and plasticity of their morphological characters. Genetic attempts to identify species are hampered by the slow rate of mitochondrial sequence evolution characteristic of sponges and some other basal metazoans. Here we determine species boundaries of the Caribbean coral reef sponge genus Callyspongia using a multilocus, model-based approach...

Investigation of nuclear nano-morphology marker as a biomarker for cancer risk assessment using a mouse model

Science.gov (United States)

Bista, Rajan K.; Uttam, Shikhar; Hartman, Douglas J.; Qiu, Wei; Yu, Jian; Zhang, Lin; Brand, Randall E.; Liu, Yang

2012-06-01

The development of accurate and clinically applicable tools to assess cancer risk is essential to define candidates to undergo screening for early-stage cancers at a curable stage or provide a novel method to monitor chemoprevention treatments. With the use of our recently developed optical technology--spatial-domain low-coherence quantitative phase microscopy (SL-QPM), we have derived a novel optical biomarker characterized by structure-derived optical path length (OPL) properties from the cell nucleus on the standard histology and cytology specimens, which quantifies the nano-structural alterations within the cell nucleus at the nanoscale sensitivity, referred to as nano-morphology marker. The aim of this study is to evaluate the feasibility of the nuclear nano-morphology marker from histologically normal cells, extracted directly from the standard histology specimens, to detect early-stage carcinogenesis, assess cancer risk, and monitor the effect of chemopreventive treatment. We used a well-established mouse model of spontaneous carcinogenesis--ApcMin mice, which develop multiple intestinal adenomas (Min) due to a germline mutation in the adenomatous polyposis coli (Apc) gene. We found that the nuclear nano-morphology marker quantified by OPL detects the development of carcinogenesis from histologically normal intestinal epithelial cells, even at an early pre-adenomatous stage (six weeks). It also exhibits a good temporal correlation with the small intestine that parallels the development of carcinogenesis and cancer risk. To further assess its ability to monitor the efficacy of chemopreventive agents, we used an established chemopreventive agent, sulindac. The nuclear nano-morphology marker is reversed toward normal after a prolonged treatment. Therefore, our proof-of-concept study establishes the feasibility of the SL-QPM derived nuclear nano-morphology marker OPL as a promising, simple and clinically applicable biomarker for cancer risk assessment and

A probabilistic approach to quantifying spatial patterns of flow regimes and network-scale connectivity

Science.gov (United States)

Garbin, Silvia; Alessi Celegon, Elisa; Fanton, Pietro; Botter, Gianluca

2017-04-01

The temporal variability of river flow regime is a key feature structuring and controlling fluvial ecological communities and ecosystem processes. In particular, streamflow variability induced by climate/landscape heterogeneities or other anthropogenic factors significantly affects the connectivity between streams with notable implication for river fragmentation. Hydrologic connectivity is a fundamental property that guarantees species persistence and ecosystem integrity in riverine systems. In riverine landscapes, most ecological transitions are flow-dependent and the structure of flow regimes may affect ecological functions of endemic biota (i.e., fish spawning or grazing of invertebrate species). Therefore, minimum flow thresholds must be guaranteed to support specific ecosystem services, like fish migration, aquatic biodiversity and habitat suitability. In this contribution, we present a probabilistic approach aiming at a spatially-explicit, quantitative assessment of hydrologic connectivity at the network-scale as derived from river flow variability. Dynamics of daily streamflows are estimated based on catchment-scale climatic and morphological features, integrating a stochastic, physically based approach that accounts for the stochasticity of rainfall with a water balance model and a geomorphic recession flow model. The non-exceedance probability of ecologically meaningful flow thresholds is used to evaluate the fragmentation of individual stream reaches, and the ensuing network-scale connectivity metrics. A multi-dimensional Poisson Process for the stochastic generation of rainfall is used to evaluate the impact of climate signature on reach-scale and catchment-scale connectivity. The analysis shows that streamflow patterns and network-scale connectivity are influenced by the topology of the river network and the spatial variability of climatic properties (rainfall, evapotranspiration). The framework offers a robust basis for the prediction of the impact of

Ecological-biological Aspects of Stipa krylovii Roshev Adaptation at the Initial Stages of Ontogenesis

Directory of Open Access Journals (Sweden)

N.S. Chistyakova

2016-08-01

Full Text Available Xerophytic cereal Stipa krylovii Roshev is interesting as a relic with extensive capabilities to adapt to severe climatic conditions of Eastern Zabaikal’ye, which allows it to occupy a vast areal. The species under study is characterized by distinctive ecological-biological peculiarities, which are underpinned by not only distribution, but historical establishment of the species. The primary goal of the research was to study ecological-biological peculiarities of adaptation of wild cereal Stipa krylovii to the habitat in Eastern Zabaikal’ye. According to the observations, Stipa krylovii is characterized by late development rate coinciding with the period of optimal heat and moisture availability. Seed embryos have a well-developed scutellum, distinct structures and well differentiated embryo axis. The studies identified no lateral or secondary roots in the cereal. In nature, seeds of S. krylovii are characterized by profound organic peace period, which persists in the course of sprouting under optimal conditions. Peace period of S. krylovii caryopses is likely to be due to the presence of sprouting inhibitors and is overcome in moist autumn period. Seed viability was determined under various soil moisture parameters up to its complete water capacity; the impact of moisture content on seed sprouting rate was studied. The results of the tests on caryopses sprouting with various moisture content demonstrated that at minimum moisture content (10% S. krylovii forms epidermal hairs on coleorhiza; 30% of soil water content is enough for growth activation, viability and sprouting rate of this cereal, which is due to its xerophytic nature. This morphological peculiarity is likely to ensure in nature sprouting of these species in early spring, when soil contain minimum water. Intensity of the initial growth was determined by a number of parameters: rate of change in linear growth of trunk and root parts of the embryo, growth of dry substance of

Evolution of morphology and locomotor performance in anurans: relationships with microhabitat diversification.

Science.gov (United States)

Citadini, J M; Brandt, R; Williams, C R; Gomes, F R

2018-03-01

The relationships between morphology, performance, behavior and ecology provide evidence for multiple and complex phenotypic adaptations. The anuran body plan, for example, is evolutionarily conserved and shows clear specializations to jumping performance back at least to the early Jurassic. However, there are instances of more recent adaptation to habit diversity in the post-cranial skeleton, including relative limb length. The present study tested adaptive models of morphological evolution in anurans associated with the diversity of microhabitat use (semi-aquatic arboreal, fossorial, torrent, and terrestrial) in species of anuran amphibians from Brazil and Australia. We use phylogenetic comparative methods to determine which evolutionary models, including Brownian motion (BM) and Ornstein-Uhlenbeck (OU) are consistent with morphological variation observed across anuran species. Furthermore, this study investigated the relationship of maximum distance jumped as a function of components of morphological variables and microhabitat use. We found there are multiple optima of limb lengths associated to different microhabitats with a trend of increasing hindlimbs in torrent, arboreal, semi-aquatic whereas fossorial and terrestrial species evolve toward optima with shorter hindlimbs. Moreover, arboreal, semi-aquatic and torrent anurans have higher jumping performance and longer hindlimbs, when compared to terrestrial and fossorial species. We corroborate the hypothesis that evolutionary modifications of overall limb morphology have been important in the diversification of locomotor performance along the anuran phylogeny. Such evolutionary changes converged in different phylogenetic groups adapted to similar microhabitat use in two different zoogeographical regions. © 2018 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2018 European Society For Evolutionary Biology.

A rapid method combining Golgi and Nissl staining to study neuronal morphology and cytoarchitecture.

Science.gov (United States)

Pilati, Nadia; Barker, Matthew; Panteleimonitis, Sofoklis; Donga, Revers; Hamann, Martine

2008-06-01

The Golgi silver impregnation technique gives detailed information on neuronal morphology of the few neurons it labels, whereas the majority remain unstained. In contrast, the Nissl staining technique allows for consistent labeling of the whole neuronal population but gives very limited information on neuronal morphology. Most studies characterizing neuronal cell types in the context of their distribution within the tissue slice tend to use the Golgi silver impregnation technique for neuronal morphology followed by deimpregnation as a prerequisite for showing that neuron's histological location by subsequent Nissl staining. Here, we describe a rapid method combining Golgi silver impregnation with cresyl violet staining that provides a useful and simple approach to combining cellular morphology with cytoarchitecture without the need for deimpregnating the tissue. Our method allowed us to identify neurons of the facial nucleus and the supratrigeminal nucleus, as well as assessing cellular distribution within layers of the dorsal cochlear nucleus. With this method, we also have been able to directly compare morphological characteristics of neuronal somata at the dorsal cochlear nucleus when labeled with cresyl violet with those obtained with the Golgi method, and we found that cresyl violet-labeled cell bodies appear smaller at high cellular densities. Our observation suggests that cresyl violet staining is inadequate to quantify differences in soma sizes.

Morphological change in Newfoundland caribou: Effects of abundance and climate

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Shane P. Mahoney

2011-04-01

Full Text Available The demographic and environmental influences on large mammal morphology are central questions in ecology. We investigated the effects of population abundance and climate on body size and number of male antler points for the La Poile and Middle Ridge caribou (Rangifer tarandus, L. 1758 herds, Newfoundland, Canada. Across 40 years and 20-fold changes in abundance, adult males and females exhibited diminished stature as indicated by jawbone size (diastema and total mandible length and the number of antler points at the time of harvest. Associations between jawbone size and population abundance at birth were consistently negative for both herds, both sexes, and all age classes. Large-scale climate patterns, as measured by the North Atlantic Oscillation in the winter prior to birth, were also negatively associated with jawbone size. Declines in male antler size, as measured by the number of antler points, were not well predicted by either abundance or climate, suggesting other factors (e.g., current, rather than latent, foraging conditions may be involved. We conclude that these morphological changes indicate competition for food resources.

Morphological and ontogenetic stratification of abyssal and hadal Eurythenes gryllus sensu lato (Amphipoda: Lysianassoidea) from the Peru-Chile Trench

Science.gov (United States)

Eustace, Ryan M.; Ritchie, Heather; Kilgallen, Niamh M.; Piertney, Stuart B.; Jamieson, Alan J.

2016-03-01

The globally ubiquitous lysianassoid amphipod, Eurythenes gryllus, has been shown to consist of multiple genetically distinct cryptic taxa, with depth considered a major driver of speciation and morphological divergence. Here we examine morphological variation of E. gryllus sensu lato through a continuous depth distribution that spans from abyssal (3000-6000 m) into hadal depths (>6000 m) in the Peru-Chile Trench (SE Pacific Ocean). Three distinct morphospecies were identified: one was confirmed as being E. magellanicus (4602-5329 m) based on DNA sequence and morphological similarity. The other two morphologically distinct species were named based upon depth of occurrence; Abyssal (4602-6173 m) and Hadal (6173-8074 m). The three Eurythenes morphospecies showed vertical ontogenetic stratification across their bathymetric range, where juveniles were found shallower in their depth range and mature females deeper. Potential ecological and evolutionary drivers that explain the observed patterns of intra and inter-specific structure, such as hydrostatic pressure and topographical isolation, are discussed.

[Applied ecology: retrospect and prospect].

Science.gov (United States)

He, Xingyuan; Zeng, Dehui

2004-10-01

Applied ecology is evolved into a principal part of modern ecology that rapidly develops. The major stimulus for the development of applied ecology roots in seeking the solutions for the problems of human populations, resources and environments. Through four decades, the science of applied ecology has been becoming a huge group of disciplines. The future for the applied ecology should concern more with human-influenced and managed ecosystems, and acknowledge humans as the components of ecosystems. Nowadays and in future, the top-priorities in applied ecology should include following fields: sustainable ecosystems and biosphere, ecosystem services and ecological design, ecological assessment of genetically modified organisms, ecology of biological invasions, epidemical ecology, ecological forecasting, ecological process and its control. The authors believe that the comprehensive and active research hotspots coupled some new traits would occur around these fields in foreseeable future.

Annual report of ecological research at the Savannah River Ecology Laboratory

International Nuclear Information System (INIS)

1984-09-01

This report summarizes research conducted at the Savannah River Ecology Laboratory (SREL) during the annual period ending August 1, 1984. SREL is a regional research facility at the Savannah River Plant operated by the University of Georgia through a contract with the Department of Energy. It is part of the University of Georgia's Institute of Ecology. The overall goal of the research is to develop an understanding of the impact of various energy technologies and management practices on the ecosystems of the southeastern United States. SREL research is conducted by interdisciplinary research teams organized under three major divisions: (1) Biogeochemical Ecology, (2) Wetlands Ecology, and (3) Stress and Wildlife Ecology

Herbarium-based studies on taxonomy, biogeography and ecology of Psilochilus (Orchidaceae).

Science.gov (United States)

Kolanowska, Marta; Naczk, Aleksandra M; Jaskuła, Radomir

2016-01-01

Psilochilus is a poorly studied orchid genus distributed from southern Mexico to south-eastern Brazil. A taxonomic revision of this Neotropical endemic based on morphological data is presented. Over 170 dried herbarium specimens and flowers preserved in liquid of Psilochilus were analyzed. Morphological variation among examined taxa was described based on multivariate analysis. To evaluate the similarity between niches occupied by various Psilochilus species ecological niche modeling (ENM) was applied. Species richness and the distribution patterns of Psilochilus representatives were analyzed based on squares of 5° latitude and longitude while similarities among floras between biogeographical units were measured using the Bray-Curtis index for presence/absence data. A new species of the P. physurifolius -complex is described based on Central American material. Psilochilus crenatifolius is reduced to the rank of variety as P. macrophyllus var. crenatifolius . A key to 18 accepted Psilochilus species is provided. The illustrations of perianth segments of all recognized taxa are presented. The climatic niches preferred by the particular Psilochilus representatives are well separated based on ecological niche modeling analysis. Their distribution is limited mainly by the isothermality and temperature seasonality. The highest Psilochilus species richness is observed in the North Andean, Panamanian, Brazilian Planalto and Central American biogeographical provinces. A high level of endemism is observed in all those regions as well as Yungas biogeographical province. Most Psilochilus species occur in areas above 800 m of elevation. The populations were most often reported from the tropical rain forest and tropical moist deciduous forest.

Inferring principles for sustainable development of business through analogies from ecological systems

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K. Sriram

2013-03-01

Full Text Available The literature in the field of sustainable development (SD of businesses is piecemeal and diverse. This paper identifies and integrates principles that businesses could use for transformation towards SD. This is done through analogical reasoning from the source context of ecological systems to the target contexts of business socio-economic systems and machine/technology systems. The methodologies of systems thinking and morphological analysis supplement the analogical reasoning. Based on this, twelve principles for sustainable development of business are inferred for business managers and policy makers.

Morphological transformation of soot: investigation of microphysical processes during the condensation of sulphuric acid and limonene ozonolysis products vapours

Science.gov (United States)

Pathak, R. K. P.; Pei, X.; Hallquist, M.; Pagels, J. H.

2017-12-01

Morphological transformation of soot particle by condensation of low volatility materials on it is a dominant atmospheric process with serious implications for its optical and hygroscopic properties, and atmospheric lifetime. In this study, the morphological transformation of soot agglomerate under the influence of condensation of vapours of sulphuric acid, and/or limonene ozonolysis products were investigated systematically using a Differential Mobility Analyser-Aerosol Particle Mass Analyser (DMA-APM) and the Tandem DMA techniques integrated with a laminar flow-tube system. We discovered that the morphology transformation of soot in general was a sequence of two-step process, i.e. (i) filling of void space within soot agglomerate; (ii) growth of particle diameter. These two steps followed and complimented each other. In the very beginning the filling was the dominant process followed by growth until it led to the accumulation of enough material that in turn exerted surface forces that eventually facilitated the further filling. The filling of void space was constrained by the initial morphology of fresh soot and the nature and amount of the material condensed. This process continued in several sequential steps until all void space within the soot agglomerate was filled completely and then growth of a spherical particle continued as long as mass was condensed on it. In this study, we developed a framework to quantify the microphysical transformation of soot upon the condensation of various materials. The framework utilized experimental data and hypothesis of ideal sphere growth and filling of voids to quantify the distribution of condensed materials in these two processes complimenting each other. Using this framework, we have quantified the percentage of material that went into processes of particle growth and void filling at each step. Using the same framework, we further estimated the fraction of internal voids and open voids and used this information to derive

Nesting biology, morphological remarks, and description of the mature larva of Mellinus arvensis obscurus (Hymenoptera: Crabronidae) in Nepal

International Nuclear Information System (INIS)

Boesi, R.; Polidori, C.; Andrietti, F.; Gayubo, S.F.; Tormos, J.; Asis, J.D.

2007-01-01

Recently re-named as a sub-species of Mellinus arvensis, Mellinus arvensis obscurus Handlirsch 1888 was investigated ecologically and morphologically in Nepal, in order to underline the most important differences with the well known M. arvensis arvensis. Mellinus arvensis obscurus females nested in clumped aggregations on inclined plains at high altitudes, both on sunny bare soil and on a shaded grassy one. Beginning of monsoon season probably interfered with wasp activity, and females performed few provisioning flights during the day. Prey consisted of a broad range of Diptera, except for one case of a spider. Many females were observed not provisioning a nest but floating on the nesting site, and many intraspecific interactions suggested a high degree of usurpation attempts. At least one species of flies and two of ants probably acted as natural enemies of the wasp. Morphological observations on females showed that the Nepal population shares more similarities (shape of tergite I, body punctation) with the European populations than with the closer Japanese population; melanization is strong, according to west-east and altitudinal cline. The mature larva of M. arvensis obscurus Handlirsch is described, illustrated, and compared with the other mature larva of the genus. The differences between both larvae mainly lie in the presence/absence, and number or differentiation of integumental structures. We conclude that morphological traits are more important than ecological and behavioral ones in distinguishing M. arvensis obscurus from M. arvensis arvensis. (author) [es

Education in ecology

International Nuclear Information System (INIS)

Marek, R.

1993-01-01

It is not enough to convey knowledge, insights and attitudes if education in ecology is to have fruitful effects. Space and opportunity for action and creativity must be provided in addition. This includes personal consumer habits (eating, transport, hygiene, leisure activities etc.); an individual workplace - in this case school - that can be shaped according to ecological needs. Beyond this, ecological maturation should not be confined to, but should transcend school, for instance in youth groups, citizens' committees, political parties. If school does not inspire action - including action outside school -then education in ecology could be smothered by the Midas effect, where all life is reduced to material, to the curriculum in this case. This book presents ecological projects that have been tried at schools. They aim at an education in ecology that is oriented to the pupil and open to experience. They could be an incentive for colleagues to conduct similar projects at their schools. The projects work from the pupils' own experience and aim at concrete action and activities in his or her own environment. They should encourage teachers to venture outside the classroom with the pupils and teach ecology where it takes place. (orig.) [de

The ecological law and ecological human rights: to the question on necessity of formation

OpenAIRE

Khvorostov A. J.

2012-01-01

Necessity of the ecological law is determined by presence of ecological crisis and formed at formation of ecological function of the state. Ecological human rights and the citizen are natural human rights, however should be legally fixed and guaranteed by the state. The further functioning of a society is impossible without observance of norms of the ecological law and ecological human rights.

[Ecological memory and its potential applications in ecology: a review].

Science.gov (United States)

Sun, Zhong-yu; Ren, Hai

2011-03-01

Ecological memory (EM) is defined as the capability of the past states or experiences of a community to influence the present or future ecological responses of the community. As a relatively new concept, EM has received considerable attention in the study of ecosystem structure and function, such as community succession, ecological restoration, biological invasion, and natural resource management. This review summarized the definition, components, and categories of EM, and discussed the possible mechanisms and affecting factors of EM. Also, the potential applications of EM were proposed, in order to further understand the mechanisms of community succession and to guide ecological restoration.

The parachute morphology as equilibrium morphology of vesicle-polymer hybrids?

NARCIS (Netherlands)

Jung, M.; Hubert, D.H.W.; Herk, van A.M.; German, A.L.

2000-01-01

Polymerisation in vesicles leads to novel polymer colloid morphologies. Two morphologies are currently reported: the triple-shell and the parachute morphology. The termodynamic analysis of these two morphologies, presented here, stresses the importance of considering interfacial energies between

The development of ecological impact assessment in China.

Science.gov (United States)

Liu, Xuehua; Li, Zhouyuan; Liao, Chenghao; Wang, Qing; Zhu, Annah; Li, Dong; Li, Yajun; Tang, Zhuo

2015-12-01

The balance between economic development and ecological conservation in China has become a critical issue in recent decades. Ecological impact assessment (EcoIA) was established beginning in the 1980s as a component of environmental impact assessment (EIA) that focuses specifically on human-related changes in ecosystem structure and function. EcoIA has since been widely applied throughout the country with continuous refinements in theory and practice. As compared to EIA, EcoIA is often performed at a larger scale in the long-term, and thus requires more advanced tools and techniques to quantify and assess. This paper reviews the development of EcoIA over the past 30years in China, with specific consideration given to refinements in legislation and methodology. Three stages in the development of EcoIA in China are identified, along with their achievements and limitations. Supplementing this qualitative analysis, the paper also provides a quantitative bibliometrics review of academic publications concerning EcoIA in China over the three identified stages. Lastly, general trends in the development of EcoIA are summarized with the aim of conveying potential future trajectories. This review is intended to introduce the EcoIA system to scholars interested in the growing field of environmental management in China. Copyright © 2015 Elsevier Ltd. All rights reserved.

Quantifying Transmission.

Science.gov (United States)

Woolhouse, Mark

2017-07-01

Transmissibility is the defining characteristic of infectious diseases. Quantifying transmission matters for understanding infectious disease epidemiology and designing evidence-based disease control programs. Tracing individual transmission events can be achieved by epidemiological investigation coupled with pathogen typing or genome sequencing. Individual infectiousness can be estimated by measuring pathogen loads, but few studies have directly estimated the ability of infected hosts to transmit to uninfected hosts. Individuals' opportunities to transmit infection are dependent on behavioral and other risk factors relevant given the transmission route of the pathogen concerned. Transmission at the population level can be quantified through knowledge of risk factors in the population or phylogeographic analysis of pathogen sequence data. Mathematical model-based approaches require estimation of the per capita transmission rate and basic reproduction number, obtained by fitting models to case data and/or analysis of pathogen sequence data. Heterogeneities in infectiousness, contact behavior, and susceptibility can have substantial effects on the epidemiology of an infectious disease, so estimates of only mean values may be insufficient. For some pathogens, super-shedders (infected individuals who are highly infectious) and super-spreaders (individuals with more opportunities to transmit infection) may be important. Future work on quantifying transmission should involve integrated analyses of multiple data sources.

ECOLOGICAL CONSCIOUSNESS AS ONE OF THE MAIN PRINCIPLES OF ECOLOGICAL POLICY

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Diana O. Dushkova

2017-09-01

Full Text Available The article presents the concept of ecological consciousness and analyzes main features of its development and implementation in the environmental policy in European practice on the example of Germany. The study of German experience is conditioned by the fact that among the other developed countries of the world Germany is the leading country in its active work carried out at all levels of the environmental policy. It is shown that actions aimed at the development of ecological culture and environmental education of the civil society in Germany are of the same priority as the use of renewable energy, development of green technologies, etc. The article provides an overview of the most important publications devoted to the phenomenon of ecological consciousness and highlights different approaches to this definition. Based on the German experience, it defines the prerequisites, main roots and sources of ecological consciousness creation and the ways in which it can be involved in the regional programs on sustainable development and ecological policy. It analyzes the main practical approaches to the implementation of the principles of ecological consciousness in Germany as well as the role of environmental organizations in the realization of environmentally oriented activities. Therefore, it presents the main results of socio-ecological surveys conducted in Germany and Russia and gives their comparative analysis. It indicates possible ways to transfer the German experience in the Russian context to improve the ecological awareness of the Russian society and to arise its ecological activity in addressing environmental issues.

Mirid (Hemiptera: Heteroptera) specialists of sticky plants: adaptations, interactions, and ecological implications.

Science.gov (United States)

Wheeler, Alfred G; Krimmel, Billy A

2015-01-07

Sticky plants-those having glandular trichomes (hairs) that produce adhesive, viscous exudates-can impede the movement of, and entrap, generalist insects. Disparate arthropod groups have adapted to these widespread and taxonomically diverse plants, yet their interactions with glandular hosts rarely are incorporated into broad ecological theory. Ecologists and entomologists might be unaware of even well-documented examples of insects that are sticky-plant specialists. The hemipteran family Miridae (more specifically, the omnivorous Dicyphini: Dicyphina) is the best-known group of arthropods that specializes on sticky plants. In the first synthesis of relationships with glandular plants for any insect family, we review mirid interactions with sticky hosts, including their adaptations (behavioral, morphological, and physiological) and mutualisms with carnivorous plants, and the ecological and agricultural implications of mirid-sticky plant systems. We propose that mirid research applies generally to tritrophic interactions on trichome-defended plants, enhances an understanding of insect-plant interactions, and provides information useful in managing crop pests.

Morphometric Traits of Muscovy Ducks from Two Agro Ecological Zones of Nigeria

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Yakubu, A.

2011-01-01

Full Text Available Morphological variation between Muscovy ducks from the guinea savannah and rainforest zones of Nigeria was examined using multivariate discriminant analysis. Data comprised eight morphometric traits measured in a total of 435 adult ducks randomly selected in the two agro-ecological zones. Common descriptive statistics showed that ducks from the rainforest zone had higher (P< 0.05 body weight, foot length and thigh circumference, while their guinea savannah counterparts were longer (P< 0.05 in the neck. Stepwise discriminant analysis indicated that foot length, neck length, thigh circumference and body length were more effective in discriminating between the duck populations. The low Mahalanobis distance of 3.39, as revealed by the canonical discriminant analysis, is an indication of high gene flow between ducks from the two agro-ecological zones. The cluster analysis also revealed the homogeneity of the genetic identity of the duck populations. The present information will be the basis for further characterization, conservation and sustainable genetic improvement strategies for indigenous ducks.

Agro ecological zonification of the Putumayo Area

International Nuclear Information System (INIS)

Villaneda Vivas, E.

1989-01-01

The Agro ecological zonification of the Putumayo Area, defines and it quantifies reas according to environmental factors as climate, material parental and soil. In this work it is presented the astronomical localization, the geographical location and the detailed description of each of the agro ecological reas, that conform the Department. This zonification allowed through the delimitation of the different earth classes and of the quantification of the same ones, to extract fundamental information for the knowledge of the geography and for the planning of the agricultural and forest production in rational form. According to the study 85.8 percent of the lands corresponds to the warm thermal soil, 5.7 percent to the half soil, 7.2 percent to the cold and 1.3 percent to the very cold one and nival. As for the counties of humidity 91.6 percent presents humid climatic conditions and 8.4 percent it receives excessive humidity. The vocation of the lands of the Putumayo is however predominant forestall, some reas has possibilities of agricultural exploitation maintaining the vegetable covering. The reas of agricultural vocation has an extension of 43.250 there is equivalent to 1.7 percent of the department the forest areas have an extension of 2.445.250 there is. 27.4 percent presents an agricultural possibility and 30.7 percent they are areas of protection y/o reforestation

Ecological restoration of litter in mined areas

Science.gov (United States)

Teresinha Gonçalves Bizuti, Denise; Nino Diniz, Najara; Schweizer, Daniella; de Marchi Soares, Thaís; Casagrande, José Carlos; Henrique Santin Brancalion, Pedro

2016-04-01

The success of ecological restoration projects depends on going monitoring of key ecological variables to determine if a desired trajectory has been established and, in the case of mining sites, nutrient cycling recovery plays an utmost importance. This study aimed to quantify and compare the annual litter production in native forests, and in restoration sites established in bauxite mines. We collected samples in 6 native forest remnants and 6 year-old restoration sites every month for a period of one year, in the city of Poços de Caldas/MG, SE Brazil. 120 wire collectors were used (0,6x0,6) and suspended 30cm above the soil surface. The material was dried until constant weight, weighed and fractionated in leaves, branches and reproductive material. The average annual litter production was 2,6 Mg ha-1 in native forests and 2,1 in forest in restoration sites, differing statistically. Litter production was higher in the rainy season, especially in September. Among the litter components, the largest contributor to total production was the fraction leaves, with 55,4% of the total dry weight of material collected, followed by reproductive material which contributed 24,5% and branches, with 20%. We conclude that the young areas in restoration process already restored important part, but still below the production observed in native areas.

Ecological Trait Composition of Freshwater Fish Across Gradients of Environmental Variability in North-Eastern Australia

Science.gov (United States)

Kennard, M. J.; Pusey, B. J.; Arthington, A. H.

2005-05-01

North-eastern Australia encompasses 18o of latitude, monsoonal/tropical to sub-tropical/temperate climates, geomorphologically diverse rivers, and flow regimes with markedly varied seasonality, constancy and predictability. Fish assemblages in the region vary in relation to the predictability of aquatic habitat availability and other topographic, climatic and/or biogeographic factors. This paper examines how environmental, biogeographic and phylogenetic factors may constrain ecological trait composition at local and regional scales. We derived 17 categories of ecological traits to describe the morphology, behaviour, habitat, life history and trophic characteristics of 114 fish species from 64 river basins. Trait composition varied substantially across the region. The number of riffle dwelling species, maximum size and longevity of fishes was greater in the hydrologically predictable and constant rivers of the Wet Tropics region than in more unpredictable or seasonal environments. The importance of herbivory was also greater in the tropics. Historical biogeographic and phylogenetic factors may confound our ability to understand the role of environmental factors in determining spatial variation in ecological trait composition. Understanding the functional linkages between environmental drivers of fish species distributions via their ecological characteristics should provide a foundation for predicting future impacts of environmental change in a region of Australia subject to increasing human pressures.

Convergent and divergent patterns of morphological differentiation provide more evidence for reproductive character displacement in a wood cricket Gryllus fultoni (Orthoptera: Gryllidae

Directory of Open Access Journals (Sweden)

Choe Jae

2009-02-01

Full Text Available Abstract Background In ecological character displacement, traits involved in reproductive isolation may not evolve in arbitrary directions when changes in these traits are by-products of adaptation to an ecological niche. In reproductive character displacement, however, selection acts directly on reproductive characters to enhance the degree of reproductive isolation between sympatric populations. Thus, the direction of change in reproductive characters may be arbitrary in relation to changes in other morphological characters. We characterized both tegminal characters and characters indicative of body size in sympatric and allopatric populations of Gryllus fultoni, a species displaying character displacement in its calling song characters in areas of sympatry with G. vernalis populations, to infer the nature and direction of selection acting on reproductive and morphological characters in sympatry. Results Except for mirror area, the number of teeth in a file, and ovipositor length of G. fultoni, all male and female morphological characters in G. fultoni and G. vernalis exhibited a uniform tendency to decrease in size with increasing latitude. There was no significant variation in female morphological characters between sympatric and allopatric G. fultoni populations. However, males of sympatric and allopatric G. fultoni populations significantly differed in head width, hind femur length, and mirror area even after controlling for clinal factors. Head width and hind femur length of G. fultoni were more similar to those of G. vernalis in sympatric populations than in allopatric populations, resulting in morphological convergence of G. fultoni and G. vernalis in sympatry. However, the mirror area of G. fultoni displayed the divergent pattern in relation to the sympatric G. vernalis populations. Conclusion Divergence-enhancing selection may be acting on mirror area as well as calling song characters, whereas local adaptation or clinal effects may

Morphological divergence between three Arctic charr morphs - the significance of the deep-water environment.

Science.gov (United States)

Skoglund, Sigrid; Siwertsson, Anna; Amundsen, Per-Arne; Knudsen, Rune

2015-08-01

Morphological divergence was evident among three sympatric morphs of Arctic charr (Salvelinus alpinus (L.)) that are ecologically diverged along the shallow-, deep-water resource axis in a subarctic postglacial lake (Norway). The two deep-water (profundal) spawning morphs, a benthivore (PB-morph) and a piscivore (PP-morph), have evolved under identical abiotic conditions with constant low light and temperature levels in their deep-water habitat, and were morphologically most similar. However, they differed in important head traits (e.g., eye and mouth size) related to their different diet specializations. The small-sized PB-morph had a paedomorphic appearance with a blunt head shape, large eyes, and a deep body shape adapted to their profundal lifestyle feeding on submerged benthos from soft, deep-water sediments. The PP-morph had a robust head, large mouth with numerous teeth, and an elongated body shape strongly related to their piscivorous behavior. The littoral spawning omnivore morph (LO-morph) predominantly utilizes the shallow benthic-pelagic habitat and food resources. Compared to the deep-water morphs, the LO-morph had smaller head relative to body size. The LO-morph exhibited traits typical for both shallow-water benthic feeding (e.g., large body depths and small eyes) and planktivorous feeding in the pelagic habitat (e.g., streamlined body shape and small mouth). The development of morphological differences within the same deep-water habitat for the PB- and PP-morphs highlights the potential of biotic factors and ecological interactions to promote further divergence in the evolution of polymorphism in a tentative incipient speciation process. The diversity of deep-water charr in this study represents a novelty in the Arctic charr polymorphism as a truly deep-water piscivore morph has to our knowledge not been described elsewhere.

From patterns to emerging processes in mechanistic urban ecology.

Science.gov (United States)

Shochat, Eyal; Warren, Paige S; Faeth, Stanley H; McIntyre, Nancy E; Hope, Diane

2006-04-01

Rapid urbanization has become an area of crucial concern in conservation owing to the radical changes in habitat structure and loss of species engendered by urban and suburban development. Here, we draw on recent mechanistic ecological studies to argue that, in addition to altered habitat structure, three major processes contribute to the patterns of reduced species diversity and elevated abundance of many species in urban environments. These activities, in turn, lead to changes in animal behavior, morphology and genetics, as well as in selection pressures on animals and plants. Thus, the key to understanding urban patterns is to balance studying processes at the individual level with an integrated examination of environmental forces at the ecosystem scale.

Application of the Fourier descriptors method to the morphological classification of particles in geological materials

International Nuclear Information System (INIS)

Manzanas Lopez, J.; Santiago Buey, C.

2010-01-01

This study focuses on the use of Fourier descriptors to quantitatively describe the morphology of particles aggregates or pores in geological materials. Firstly, the mathematical fundaments of the method are explained. Then, the Fourier descriptors method is applied to the Krumbein Scale, a system of measuring roundness and sphericity of particles. the analysis of the comparison shows that there is good correlation between the Sphericity parameter at the Krumbein classifications and the value of the modulus of the Fourier descriptor No-1. This good correlation, along with the mathematical precision which allows to prevent subjective valorisations in the morphological description, corroborates the validity of the method to quantify the sphericity elongation of particles in geological materials. (Author) 12 refs.

Genetic Allee effects and their interaction with ecological Allee effects.

Science.gov (United States)

Wittmann, Meike J; Stuis, Hanna; Metzler, Dirk

2018-01-01

It is now widely accepted that genetic processes such as inbreeding depression and loss of genetic variation can increase the extinction risk of small populations. However, it is generally unclear whether extinction risk from genetic causes gradually increases with decreasing population size or whether there is a sharp transition around a specific threshold population size. In the ecological literature, such threshold phenomena are called 'strong Allee effects' and they can arise for example from mate limitation in small populations. In this study, we aim to (i) develop a meaningful notion of a 'strong genetic Allee effect', (ii) explore whether and under what conditions such an effect can arise from inbreeding depression due to recessive deleterious mutations, and (iii) quantify the interaction of potential genetic Allee effects with the well-known mate-finding Allee effect. We define a strong genetic Allee effect as a genetic process that causes a population's survival probability to be a sigmoid function of its initial size. The inflection point of this function defines the critical population size. To characterize survival-probability curves, we develop and analyse simple stochastic models for the ecology and genetics of small populations. Our results indicate that inbreeding depression can indeed cause a strong genetic Allee effect, but only if individuals carry sufficiently many deleterious mutations (lethal equivalents). Populations suffering from a genetic Allee effect often first grow, then decline as inbreeding depression sets in and then potentially recover as deleterious mutations are purged. Critical population sizes of ecological and genetic Allee effects appear to be often additive, but even superadditive interactions are possible. Many published estimates for the number of lethal equivalents in birds and mammals fall in the parameter range where strong genetic Allee effects are expected. Unfortunately, extinction risk due to genetic Allee effects

Sagittal synostosis: I. Preoperative morphology of the skull

DEFF Research Database (Denmark)

Guimaraes-Ferreira, J.; Gewalli, F.; David, L.

2006-01-01

The aim of this study was to characterise the preoperative morphology of the skull in sagittal synostosis in an objective and quantified way. The shapes of the skulls of 105 patients with isolated premature synostosis of the sagittal suture ( SS group) were studied and compared with those......, skull base, and orbit ( 42 in the lateral and 46 in the frontal projections), the production of plots of mean shape for each group, and the intergroup comparison of a series of 81 variables ( linear distance between selected landmarks, and angles defined by groups of three landmarks). Data from...... skull width. Comparison of the mean values of an SS subgroup to age-matched normative data showed a longer (p differ significantly...

Quantifying the "So what?" of Restoration: A Framework for Evaluating the Ecological and Socio-economic Outcomes of Restoration Activities in the Gulf of Mexico

Science.gov (United States)

Henkel, J. R.; Dausman, A.; Cowan, J.; Sutter, B.

2017-12-01

Healthy and sustainable ecosystems are essential for thriving and resilient coastal communities. As a result of settlements following the Deepwater Horizon oil spill, the Gulf Coast Ecosystem Restoration Council (Council) and other funding entities, will receive billions of dollars over the next 15 years for restoration projects and programs. These and future restoration efforts present an opportunity to improve the function of coastal wetlands in the Gulf of Mexico, and potentially address long-standing barriers to ecosystem health and resilience in the region. In its Comprehensive Plans, the Council has committed to science-based decision-making, collaboration among its eleven state and federal members, and close coordination with other Gulf restoration and conservation funding efforts including NRDA, NFWF and other federal programs to leverage resources and integrate complementary restoration efforts. To help fulfill these commitments the Council is exploring methods and tools to collect and assess data to evaluate and report on both ecological and socio-economic outcomes of restoration projects. Application of these tools in coordination with restoration partners, will demonstrate the cascading benefits of ecosystem restoration in a quantifiable way, and can help decision-makers increase investments in ecosystem restoration that will support the long-term sustainability of coastal systems. An understanding of ecosystem function and services can also provide a transparent lens for communicating the results of successful ecosystem restoration projects to the public (helping answer the "So what?" of ecosystem restoration). As the Council moves forward making decisions based on the best available science, improving ecosystem functioning and services will play a role in project and program selection and will result in more resilient ecosystems. This will enable the Council to help communities enhance their ability to recover from natural and manmade disasters and

Sulcal Morphology Analysis from MRI Data for Classification of Alzheimer's Disease

DEFF Research Database (Denmark)

Plocharski, Maciej

2017-01-01

Alzheimer's disease (AD) is a progressive and irreversible neurodegenerative disorder, characterized by structural changes in the brain, leading to a gradual loss of cognitive functions, and eventually death. A successful diagnosis of the disease is very difficult, since both the early symptoms...... and the structural brain changes can be mistaken for normal ageing or for other forms for dementia. An early detection of AD has important implications for future developments of disease-modifying treatments. The aim of this thesis was to utilize the morphology of cortical sulci as a biomarker for quantifying...

Ecological palaeoecology: a missing link between ecology and evolution

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Rull, V.

2014-12-01

Full Text Available Palaeoecology is more than a palaeoenvironmental discipline; it is a science that is well-suited for supplying the empirical evidence necessary to test ecological hypotheses and contributes to our understanding of the interface of ecology and evolution. A critical time frame in palaeoecology is the often-overlooked Q-time dimension (centuries to millennia, which tends to be the most appropriate time dimension to examine ecology–evolution interactions. This paper discusses these topics from a conceptual perspective and provides examples of the contributions of palaeoecology to the study of ecology–evolution interactions. It also admonishes researchers about the threats of overlooking palaeoecology. Specifically, this paper argues that the neglect of palaeoecology may result in the loss of empirical support for ecology and its interactions with evolution as DNA-based phylogenetic and phylogeographic studies become more and more prevalent. The main concepts discussed are the time continuum, the notion of ecological palaeoecology and the empirical nature of palaeoecology in the face of more hypothetical approaches. More practically speaking, several examples are provided that highlight the utility of ecological palaeoecology for understanding a variety of processes, including ecological succession, community– environment equilibria, community assembly, biotic responses to environmental change, speciation and extinction, and biodiversity conservation. The ecology–evolution interface is analysed using two processes in which these disciplines interact intensively: ecological succession and long-range migration. This work concludes that both ecological palaeoecology (including ancient DNA records and DNA-based phylogenetics and phylogeography are needed to better understand the biosphere ecologically and the processes occurring at the ecology–evolution interface.La paleoecología es más que una disciplina ambiental, ya que proporciona las

Quantifying the effect of ecological restoration on soil erosion in China's Loess Plateau region: an application of the MMF approach.

Science.gov (United States)

Li, Changbin; Qi, Jiaguo; Feng, Zhaodong; Yin, Runsheng; Guo, Biyun; Zhang, Feng; Zou, Songbing

2010-03-01

Land degradation due to erosion is one of the most serious environmental problems in China. To reduce land degradation, the government has taken a number of conservation and restoration measures, including the Sloping Land Conversion Program (SLCP), which was launched in 1999. A logical question is whether these measures have reduced soil erosion at the regional level. The objective of this article is to answer this question by assessing soil erosion dynamics in the Zuli River basin in the Loess Plateau of China from 1999 to 2006. The MMF (Morgan, Morgan and Finney) model was used to simulate changes in runoff and soil erosion over the period of time during which ecological restoration projects were implemented. Some model variables were derived from remotely sensed images to provide improved land surface representation. With an overall accuracy rate of 0.67, our simulations show that increased ground vegetation cover, especially in forestlands and grasslands, has reduced soil erosion by 38.8% on average from 1999 to 2006. During the same time period, however, the change in rainfall pattern has caused a 13.1% +/- 4.3% increase in soil erosion, resulting in a net 25.7% +/- 8.5% reduction in soil erosion. This suggests that China's various ecological restoration efforts have been effective in reducing soil loss.

Morphologic analysis of the SKI preparedness

International Nuclear Information System (INIS)

Stenstroem, Maria

2003-08-01

The Swedish Nuclear Power Inspectorate (SKI) is an independent government agency responsible for technical assessments and information concerning accidents involving nuclear facilities at home and abroad. With the events of September 11 in New York and Washington D.C., circumstances have also changed for Swedish government agencies. Increased focus had been placed on a broadened threat spectrum, especially as concerns terrorism and the use of non-conventional weapons and methods. This means that SKI must develop adequate preparedness for new types of threats and events. What types of threats, and how SKI's preparedness planning should be developed, are questions which were addressed in a study by a working group from SKI and FOI -the Swedish National Defence Research Agency. The purpose of the study was to identify serious threats and events, which would require SKI's involvement, and to analyze what resources and competencies would by needed in order for SKI to fulfill it responsibilities. Investigating a broadened threat spectrum involves defining and analyzing a multi-dimensional problem complex, which is both difficult to quantify and involves very complicated internal relationships. Morphological analysis is a method for structuring and analyzing such problem complexes, and for developing models based on natural language concepts. The working group developed and studied ten different scenarios, which defined the parameter space for a broadened threat spectrum for SKI. On the basis of these scenarios, a morphological model was developed which describes the demands that these scenarios place on SKI as an organization. On the basis of this, a further morphological model was developed, in order to systematically dimension the resources that would be needed in the face of these demands. Through this analysis, a clearer picture of the demands and required resources for future threats has emerged. The information and insights generated will serve to better develop

Land-Use History and Contemporary Management Inform an Ecological Reference Model for Longleaf Pine Woodland Understory Plant Communities.

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Brudvig, Lars A. [Department of Plant Biology, Michigan State University; Orrock, John L. [Department of Zoology, University of Wisconsin; Damschen, Ellen I. [Department of Zoology, University of Wisconsin; et al, et al

2014-01-23

Ecological restoration is frequently guided by reference conditions describing a successfully restored ecosystem; however, the causes and magnitude of ecosystem degradation vary, making simple knowledge of reference conditions insufficient for prioritizing and guiding restoration. Ecological reference models provide further guidance by quantifying reference conditions, as well as conditions at degraded states that deviate from reference conditions. Many reference models remain qualitative, however, limiting their utility. We quantified and evaluated a reference model for southeastern U.S. longleaf pine woodland understory plant communities. We used regression trees to classify 232 longleaf pine woodland sites at three locations along the Atlantic coastal plain based on relationships between understory plant community composition, soils lol(which broadly structure these communities), and factors associated with understory degradation, including fire frequency, agricultural history, and tree basal area. To understand the spatial generality of this model, we classified all sites together. and for each of three study locations separately. Both the regional and location-specific models produced quantifiable degradation gradients–i.e., progressive deviation from conditions at 38 reference sites, based on understory species composition, diversity and total cover, litter depth, and other attributes. Regionally, fire suppression was the most important degrading factor, followed by agricultural history, but at individual locations, agricultural history or tree basal area was most important. At one location, the influence of a degrading factor depended on soil attributes. We suggest that our regional model can help prioritize longleaf pine woodland restoration across our study region; however, due to substantial landscape-to-landscape variation, local management decisions should take into account additional factors (e.g., soil attributes). Our study demonstrates the utility

Land-Use History and Contemporary Management Inform an Ecological Reference Model for Longleaf Pine Woodland Understory Plant Communities

Science.gov (United States)

Brudvig, Lars A.; Orrock, John L.; Damschen, Ellen I.; Collins, Cathy D.; Hahn, Philip G.; Mattingly, W. Brett; Veldman, Joseph W.; Walker, Joan L.

2014-01-01

Ecological restoration is frequently guided by reference conditions describing a successfully restored ecosystem; however, the causes and magnitude of ecosystem degradation vary, making simple knowledge of reference conditions insufficient for prioritizing and guiding restoration. Ecological reference models provide further guidance by quantifying reference conditions, as well as conditions at degraded states that deviate from reference conditions. Many reference models remain qualitative, however, limiting their utility. We quantified and evaluated a reference model for southeastern U.S. longleaf pine woodland understory plant communities. We used regression trees to classify 232 longleaf pine woodland sites at three locations along the Atlantic coastal plain based on relationships between understory plant community composition, soils (which broadly structure these communities), and factors associated with understory degradation, including fire frequency, agricultural history, and tree basal area. To understand the spatial generality of this model, we classified all sites together and for each of three study locations separately. Both the regional and location-specific models produced quantifiable degradation gradients–i.e., progressive deviation from conditions at 38 reference sites, based on understory species composition, diversity and total cover, litter depth, and other attributes. Regionally, fire suppression was the most important degrading factor, followed by agricultural history, but at individual locations, agricultural history or tree basal area was most important. At one location, the influence of a degrading factor depended on soil attributes. We suggest that our regional model can help prioritize longleaf pine woodland restoration across our study region; however, due to substantial landscape-to-landscape variation, local management decisions should take into account additional factors (e.g., soil attributes). Our study demonstrates the utility of

Land-use history and contemporary management inform an ecological reference model for longleaf pine woodland understory plant communities.

Directory of Open Access Journals (Sweden)

Lars A Brudvig

Full Text Available Ecological restoration is frequently guided by reference conditions describing a successfully restored ecosystem; however, the causes and magnitude of ecosystem degradation vary, making simple knowledge of reference conditions insufficient for prioritizing and guiding restoration. Ecological reference models provide further guidance by quantifying reference conditions, as well as conditions at degraded states that deviate from reference conditions. Many reference models remain qualitative, however, limiting their utility. We quantified and evaluated a reference model for southeastern U.S. longleaf pine woodland understory plant communities. We used regression trees to classify 232 longleaf pine woodland sites at three locations along the Atlantic coastal plain based on relationships between understory plant community composition, soils (which broadly structure these communities, and factors associated with understory degradation, including fire frequency, agricultural history, and tree basal area. To understand the spatial generality of this model, we classified all sites together and for each of three study locations separately. Both the regional and location-specific models produced quantifiable degradation gradients-i.e., progressive deviation from conditions at 38 reference sites, based on understory species composition, diversity and total cover, litter depth, and other attributes. Regionally, fire suppression was the most important degrading factor, followed by agricultural history, but at individual locations, agricultural history or tree basal area was most important. At one location, the influence of a degrading factor depended on soil attributes. We suggest that our regional model can help prioritize longleaf pine woodland restoration across our study region; however, due to substantial landscape-to-landscape variation, local management decisions should take into account additional factors (e.g., soil attributes. Our study demonstrates

Globalization and sustainable development: a political ecology strategy to realize ecological justice

OpenAIRE

Byrne, John; Glover, Leigh; Alrøe, Hugo Fjelsted

2006-01-01

Organic agriculture is, like mainstream agriculture, faced with the challenges of globalization and sustainable development. Ecological justice, the fair distribution of livelihoods and environments, has emerged as a key concept in efforts, on the one hand, to resist negative consequences of globalization and ecological modernization and, on the other to propose new agenda and institutional arrangements. This chapter investigates the role that ecological justice as a political ecology strateg...

Adaptive simplification and the evolution of gecko locomotion: Morphological and biomechanical consequences of losing adhesion

Science.gov (United States)

Higham, Timothy E.; Birn-Jeffery, Aleksandra V.; Collins, Clint E.; Hulsey, C. Darrin; Russell, Anthony P.

2015-01-01

Innovations permit the diversification of lineages, but they may also impose functional constraints on behaviors such as locomotion. Thus, it is not surprising that secondary simplification of novel locomotory traits has occurred several times among vertebrates and could potentially lead to exceptional divergence when constraints are relaxed. For example, the gecko adhesive system is a remarkable innovation that permits locomotion on surfaces unavailable to other animals, but has been lost or simplified in species that have reverted to a terrestrial lifestyle. We examined the functional and morphological consequences of this adaptive simplification in the Pachydactylus radiation of geckos, which exhibits multiple unambiguous losses or bouts of simplification of the adhesive system. We found that the rates of morphological and 3D locomotor kinematic evolution are elevated in those species that have simplified or lost adhesive capabilities. This finding suggests that the constraints associated with adhesion have been circumvented, permitting these species to either run faster or burrow. The association between a terrestrial lifestyle and the loss/reduction of adhesion suggests a direct link between morphology, biomechanics, and ecology. PMID:25548182

Nonlinear disruption of ecological interactions in response to nitrogen deposition.

Science.gov (United States)

Ochoa-Hueso, Raúl

2016-10-01

Global environmental change (GEC) is affecting species interactions and causing a rapid decline in biodiversity. In this study, I present a new Ecosystem Disruption Index to quantify the impacts of simulated nitrogen (N) deposition (0, 10, 20, and 50 kg N·ha -1 ·yr -1  + 6-7 kg N·ha -1 ·yr -1 background) on abiotic and biotic ecological interactions. This comparative index is based on pairwise linear and quadratic regression matrices. These matrices, calculated at the N treatment level, were constructed using a range of abiotic and biotic ecosystem constituents: soil pH, shrub cover, and the first component of several separate principal component analyses using soil fertility data (total carbon and N) and community data (annual plants, microorganisms, biocrusts, edaphic fauna) for a total of seven ecosystem constituents. Four years of N fertilization in a semiarid shrubland completely disrupted the network of ecological interactions, with a greater proportional increase in ecosystem disruption at low N addition levels. Biotic interactions, particularly those involving microbes, shrubs, and edaphic fauna, were more prone to be lost in response to N, whereas interactions involving soil properties were more resilient. In contrast, edaphic fauna was the only group directly affected by N addition, with mites and collembolans increasing their abundance with up to 20 kg N·ha -1 ·yr -1 and then decreasing, which supports the idea of higher-trophic-level organisms being more sensitive to disturbance due to more complex links with other ecosystem constituents. Future experimental studies evaluating the impacts of N deposition, and possibly other GEC drivers, on biodiversity and biotic and abiotic interactions may be able to explain results more effectively in the context of ecological networks as a key feature of ecosystem sensitivity. © 2016 by the Ecological Society of America.

Pool-Type Fishways: Two Different Morpho-Ecological Cyprinid Species Facing Plunging and Streaming Flows

Science.gov (United States)

Branco, Paulo; Santos, José M.; Katopodis, Christos; Pinheiro, António; Ferreira, Maria T.

2013-01-01

Fish are particularly sensitive to connectivity loss as their ability to reach spawning grounds is seriously affected. The most common way to circumvent a barrier to longitudinal connectivity, and to mitigate its impacts, is to implement a fish passage device. However, these structures are often non-effective for species with different morphological and ecological characteristics so there is a need to determine optimum dimensioning values and hydraulic parameters. The aim of this work is to study the behaviour and performance of two species with different ecological characteristics (Iberian barbel Luciobarbus bocagei–bottom oriented, and Iberian chub Squalius pyrenaicus–water column) in a full-scale experimental pool-type fishway that offers two different flow regimes–plunging and streaming. Results showed that both species passed through the surface notch more readily during streaming flow than during plunging flow. The surface oriented species used the surface notch more readily in streaming flow, and both species were more successful in moving upstream in streaming flow than in plunging flow. Streaming flow enhances upstream movement of both species, and seems the most suitable for fishways in river systems where a wide range of fish morpho-ecological traits are found. PMID:23741465

Identifying plant traits: a key aspect for suitable species selection in ecological restoration of semiarid slopes

Science.gov (United States)

Bochet, Esther; García-Fayos, Patricio

2017-04-01

In the context of ecological restoration, one of the greatest challenges for practitioners and scientists is to select suitable species for revegetation purposes. In semiarid environments where restoration projects often fail, little attention has been paid so far to the contribution of plant traits to species success. The objective of this study was to (1) identify plant traits associated with species success on four roadside situations along an erosion-productivity gradient, and (2) to provide an ecological framework for selecting suitable species on the basis of their morphological and functional traits, applied to semiarid environments. We analyzed the association of 10 different plant traits with species success of 296 species surveyed on the four roadside situations in a semiarid region (Valencia, Spain). Plant traits included general plant traits (longevity, woodiness) and more specific root-, seed- and leaf-related traits (root type, sprouting ability, seed mucilage, seed mass, seed susceptibility to removal, specific leaf area and leaf dry matter content). All of them were selected according to the prevailing limiting ecogeomorphological processes acting along the erosion-productivity gradient. We observed strong shifts along the erosion-productivity gradient in the traits associated to species success. At the harshest end of the gradient, the most intensely eroded and driest one, species success was mainly associated to seed resistance to removal by runoff and to resistance to drought. At the opposite end of the gradient, the most productive one, species success was associated to a competitive-ruderal plant strategy (herbaceous successful species with high specific leaf area and low leaf dry matter content). Our study provides an ecologically-based approach for selecting suitable native species on the basis or their morphological and functional traits and supports a differential trait-based selection of species as regards roadslope type and aspect. In

Ecologically relevant choanoflagellates collected from hypoxic water masses of the Baltic Sea have untypical mitochondrial cristae

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Wylezich Claudia

2012-11-01

Full Text Available Abstract Background Protist communities inhabiting oxygen depleted waters have so far been characterized through both microscopical observations and sequence based techniques. However, the lack of cultures for abundant taxa severely hampers our knowledge on the morphology, ecology and energy metabolism of hypoxic protists. Cultivation of such protists has been unsuccessful in most cases, and has never yet succeeded for choanoflagellates, even though these small bacterivorous flagellates are known to be ecologically relevant components of aquatic protist communities. Results Quantitative data for choanoflagellates and the vertical distribution of Codosiga spp. at Gotland and Landsort Deep (Baltic Sea indicate its preference for oxygen-depleted zones. Strains isolated and cultivated from these habitats revealed ultrastructural peculiarities such as mitochondria showing tubular cristae never seen before for choanoflagellates, and the first observation of intracellular prokaryotes in choanoflagellates. Analysis of their partial 28S rRNA gene sequence complements the description of two new species, Codosiga minima n. sp. and C. balthica n. sp. These are closely related with but well separated from C. gracilis (C. balthica and C. minima p-distance to C. gracilis 4.8% and 11.6%, respectively. In phylogenetic analyses the 18S rRNA gene sequences branch off together with environmental sequences from hypoxic habitats resulting in a wide cluster of hypoxic Codosiga relatives so far only known from environmental sequencing approaches. Conclusions Here, we establish the morphological and ultrastructural identity of an environmental choanoflagellate lineage. Data from microscopical observations, supplemented by findings from previous culture-independent methods, indicate that C. balthica is likely an ecologically relevant player of Baltic Sea hypoxic waters. The possession of derived mitochondria could be an adaptation to life in hypoxic environments

Genetic Coupling of Female Mate Choice with Polygenic Ecological Divergence Facilitates Stickleback Speciation.

Science.gov (United States)

Bay, Rachael A; Arnegard, Matthew E; Conte, Gina L; Best, Jacob; Bedford, Nicole L; McCann, Shaugnessy R; Dubin, Matthew E; Chan, Yingguang Frank; Jones, Felicity C; Kingsley, David M; Schluter, Dolph; Peichel, Catherine L

2017-11-06

Ecological speciation with gene flow is widespread in nature [1], but it presents a conundrum: how are associations between traits under divergent natural selection and traits that contribute to assortative mating maintained? Theoretical models suggest that genetic mechanisms inhibiting free recombination between loci underlying these two types of traits (hereafter, "genetic coupling") can facilitate speciation [2-4]. Here, we perform a direct test for genetic coupling by mapping both divergent traits and female mate choice in a classic model of ecological speciation: sympatric benthic and limnetic threespine stickleback (Gasterosteus aculeatus). By measuring mate choice in F2 hybrid females, we allowed for recombination between loci underlying assortative mating and those under divergent ecological selection. In semi-natural mating arenas in which females had access to both benthic and limnetic males, we found that F2 females mated with males similar to themselves in body size and shape. In addition, we found two quantitative trait loci (QTLs) associated with female mate choice that also predicted female morphology along the benthic-limnetic trait axis. Furthermore, a polygenic genetic model that explains adaptation to contrasting benthic and limnetic feeding niches [5] also predicted F2 female mate choice. Together, these results provide empirical evidence that genetic coupling of assortative mating with traits under divergent ecological selection helps maintain species in the face of gene flow, despite a polygenic basis for adaptation to divergent environments. Copyright © 2017 Elsevier Ltd. All rights reserved.