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Ecological theory

Richard A I Bethlehem, Carrie Allison, Emma M van Andel, Alexander I Coles, Kym Neil, Simon Baron-Cohen
Why do people act altruistically? One theory is that empathy is a driver of morality. Experimental studies of this are often confined to laboratory settings, which often lack ecological validity. In the present study we investigated whether empathy traits predict if people will act altruistically in a real-world setting, 'in the wild'. We staged a situation in public that was designed to elicit helping, and subsequently measured empathic traits in those who either stopped to help or walked past and did not help...
October 19, 2016: Social Neuroscience
Thomas L McKenzie
Physical activity is place-based, and being able to assess the number of people and their characteristics in specific locations is important both for public health surveillance and for practitioners in their design of physical activity spaces and programs. Although physical activity measurement has improved recently, many investigators avoid or are at a loss regarding the assessment of physical activity in explicit locations, especially in open environments where many people come and go in a seemingly indiscriminate fashion...
October 17, 2016: Research Quarterly for Exercise and Sport
Janette W Boughman, Richard Svanbäck
The ecological niche and mate preferences have independently been shown to be important for the process of speciation. Here we articulate a novel mechanism by which ecological niche use and mate preference can be linked to promote speciation. The degree to which individual niches are narrow and clustered affects the strength of divergent natural selection and population splitting. Similarly, the degree to which individual mate preferences are narrow and clustered affects the strength of divergent sexual selection and assortative mating between diverging forms...
October 17, 2016: Evolution; International Journal of Organic Evolution
Sylvain Billiard, Pierre Collet, Régis Ferrière, Sylvie Méléard, Viet Chi Tran
Horizontal transfer (HT) of heritable information or 'traits' (carried by genetic elements, plasmids, endosymbionts, or culture) is widespread among living organisms. Yet current ecological and evolutionary theory addressing HT is scant. We present a modeling framework for the dynamics of two populations that compete for resources and horizontally exchange (transfer) an otherwise vertically inherited trait. Competition infuences individual demographics, thereby affecting population size, which feeds back on the dynamics of transfer...
October 11, 2016: Journal of Theoretical Biology
Edwin Wouters, Frederik le Roux Booysen, Caroline Masquillier
Reviews of impact evaluations of community-based health workers and peer support groups highlight the considerable variability in the effectiveness of such support in improving antiretroviral treatment (ART) outcomes. Evidence indicates that community-based support interventions targeting patients known to be at risk will probably display better results than generic interventions aimed at the entire population of people living with HIV. It is however difficult to identify these at-risk populations, rendering knowledge on the characteristics of patients groups who are in need of community-based support a clear research priority...
2016: PloS One
Genevieve Fridlund Dunton
Theories explaining why individuals participate in physical activity often do not take into account within-person variation or dynamic patterns of change. Time-intensive methods such as Ecological Momentary Assessment (EMA) are more conductive to capturing time- and spatially-varying explanatory factors, and intraindividual fluctuations than traditional methods; and thus may yield new insights into the prediction and modeling of physical activity behavior.
October 12, 2016: Exercise and Sport Sciences Reviews
Paula Villa Martín, Jorge Hidalgo, Rafael Rubio de Casas, Miguel A Muñoz
Evolutionary and ecosystem dynamics are often treated as different processes -operating at separate timescales- even if evidence reveals that rapid evolutionary changes can feed back into ecological interactions. A recent long-term field experiment has explicitly shown that communities of competing plant species can experience very fast phenotypic diversification, and that this gives rise to enhanced complementarity in resource exploitation and to enlarged ecosystem-level productivity. Here, we build on progress made in recent years in the integration of eco-evolutionary dynamics, and present a computational approach aimed at describing these empirical findings in detail...
October 2016: PLoS Computational Biology
J David Smith, Alexandria C Zakrzewski, Jennifer M Johnson, Jeanette C Valleau
Categorization's great debate has weighed single-system exemplar theory against the possibility of alternative processing systems. We take an evolutionary perspective toward this debate to illuminate it in a new way. Animals are crucial behavioral ambassadors to this area. They reveal the roots of human categorization, the basic assumptions of vertebrates entering category tasks, and the surprising weakness of exemplar memory as a category-learning strategy. These results have joined neuroscience results to prompt important changes in categorization theory...
August 2016: Current Directions in Psychological Science
Marianne Haage, Tiit Maran, Ulrika Alm Bergvall, Bodil Elmhagen, Anders Angerbjörn
Personality exists in non-human animals and can impact fitness. There is, however, a shortage of empirical studies in certain areas within the field, and fundamental evolutionary theory on personality remains largely untested. For example, little is known on how variation in personality is maintained over evolutionary time. Theory suggests that fluctuating selection pressures due to spatiotemporal variation in conditions, e.g. food availability, is a possible mechanism and a few studies have shown that the success of different personality types varies with spatiotemporal conditions...
October 8, 2016: Oecologia
James C Stegen, Allen H Hurlbert, Ben Bond-Lamberty, Xingyuan Chen, Carolyn G Anderson, Rosalie K Chu, Francisco Dini-Andreote, Sarah J Fansler, Nancy J Hess, Malak Tfaily
The number of microbial operational taxonomic units (OTUs) within a community is akin to species richness within plant/animal ("macrobial") systems. A large literature documents OTU richness patterns, drawing comparisons to macrobial theory. There is, however, an unrecognized fundamental disconnect between OTU richness and macrobial theory: OTU richness is commonly estimated on a per-individual basis, while macrobial richness is estimated per-area. Furthermore, the range or extent of sampled environmental conditions can strongly influence a study's outcomes and conclusions, but this is not commonly addressed when studying OTU richness...
2016: Frontiers in Microbiology
Neil K Ganju, Mark J Brush, Brenda Rashleigh, Alfredo L Aretxabaleta, Pilar Del Barrio, Jason S Grear, Lora A Harris, Samuel J Lake, Grant McCardell, James O'Donnell, David K Ralston, Richard P Signell, Jeremy M Testa, Jamie M P Vaudrey
Numerical modeling has emerged over the last several decades as a widely accepted tool for investigations in environmental sciences. In estuarine research, hydrodynamic and ecological models have moved along parallel tracks with regard to complexity, refinement, computational power, and incorporation of uncertainty. Coupled hydrodynamic-ecological models have been used to assess ecosystem processes and interactions, simulate future scenarios, and evaluate remedial actions in response to eutrophication, habitat loss, and freshwater diversion...
March 2016: Estuaries and Coasts: Journal of the Estuarine Research Federation
David Costantini, Shona Smith, Shaun S Killen, Julius Nielsen, John F Steffensen
The free radical theory of ageing predicts that long-lived species should be more resistant to oxidative damage than short-lived species. Although many studies support this theory, recent studies found notable exceptions that challenge the generality of this theory. In this study, we have analysed the oxidative status of the Greenland shark (Somniosus microcephalus), which has recently been found as the longest living vertebrate animal known to science with a lifespan of at least 272years. As compared to other species, the Greenland shark had body mass-corrected values of muscle glutathione peroxidase and red blood cells protein carbonyls (metric of protein oxidative damage) above 75 percentile and below 25 percentile, respectively...
October 4, 2016: Comparative Biochemistry and Physiology. Part A, Molecular & Integrative Physiology
Yuqian Zhang, Xiumin Fu, Feiyan Wang, Ziyin Yang
Plants synthesize specialized metabolites which possess extremely important ecological functions including direct defense, indirect defense, and signaling. The optimal defense theory (ODT) proposes that defensive metabolites are preferentially allocated to the tissues with high fitness value or in locations that are easily injured. In our present study, using the model plant Nicotiana benthamiana, we found that direct defense of N. benthamiana against Spodoptera litura (Fabricius) larvae showed spatial differences in the sites producing defensive chemicals...
November 2016: Plant Science: An International Journal of Experimental Plant Biology
Duarte Araújo, Keith Davids
Individual players act as a coherent unit during team sports performance, forming a team synergy. A synergy is a collective property of a task-specific organization of individuals, such that the degrees of freedom of each individual in the system are coupled, enabling the degrees of freedom of different individuals to co-regulate each other. Here, we present an explanation for the emergence of such collective behaviors, indicating how these can be assessed and understood through the measurement of key system properties that exist, considering the contribution of each individual and beyond These include: to (i) dimensional compression, a process resulting in independent degree of freedom being coupled so that the synergy has fewer degrees of freedom than the set of components from which it arises; (ii) reciprocal compensation, if one element do not produce its function, other elements should display changes in their contributions so that task goals are still attained; (iii) interpersonal linkages, the specific contribution of each element to a group task; and (iv), degeneracy, structurally different components performing a similar, but not necessarily identical, function with respect to context...
2016: Frontiers in Psychology
Nakatada Wachi, Junko Kusumi, Hsy-Yu Tzeng, Zhi-Hui Su
The obligate mutualism of figs and fig pollinating wasps has been one of the classic models used for testing theories of coevolution and cospeciation due to the high species-specificity of these relationships. To investigate the species-specificity between figs and fig pollinators and to further understand the speciation process in obligate mutualisms, we examined the genetic differentiation and phylogenetic relationships of four closely related fig pollinating wasp species (Blastophaga nipponica, B. taiwanensis, B...
October 5, 2016: Molecular Ecology
A K Carlson, Q E Phelps, B D S Graeb
Otolith chemistry is an effective technique for evaluating fish environmental history, but its utility in fisheries management has not been comprehensively examined. Thus, a review of otolith chemistry with emphasis on management applicability is presented. More than 1500 otolith chemistry manuscripts published from 1967 to 2015 are reviewed and descriptive case studies are used to illustrate the utility of otolith chemistry as a fisheries management tool. Otolith chemistry publications span a wide variety of topics (e...
October 5, 2016: Journal of Fish Biology
Daniel Edler, Thaís Guedes, Alexander Zizka, Martin Rosvall, Alexandre Antonelli
Biogeographical regions (bioregions) reveal how different sets of species are spatially grouped and therefore are important units for conservation, historical biogeography, ecology and evolution. Several methods have been developed to identify bioregions based on species distribution data rather than expert opinion. One approach successfully applies network theory to simplify and highlight the underlying structure in species distributions. However, this method lacks tools for simple and efficient analysis. Here we present Infomap Bioregions, an interactive web application that inputs species distribution data and generates bioregion maps...
October 1, 2016: Systematic Biology
Michael T France, Helena Mendes-Soares, Larry J Forney
: Lactobacillus crispatus and Lactobacillus iners are common inhabitants of the healthy human vagina. These two species are closely related and are thought to perform similar ecological functions in the vaginal environment. Temporal data on the vaginal microbiome has shown that non-transient instances of co-occurrence are uncommon while transitions from an L. iners dominated community to one dominated by L. crispatus, and vice versa, occur often. This suggests that there is substantial overlap in the fundamental niche of these species...
September 30, 2016: Applied and Environmental Microbiology
Kathleen S J Preston, Allen W Gottfried, Pamella H Oliver, Adele Eskeles Gottfried, Danielle E Delany, Sirena M Ibrahim
The construct of positive family relationships (PFR), defined as family members getting along well and supporting each other, was investigated in a long-term prospective study. A newly constructed scale of positive family relationships developed using the nominal response model of item-response theory, was subject to a longitudinal network of relations analysis. The conceptualization for this research was founded on a positive psychology framework. Data derived from the Fullerton Longitudinal Study and spanned 20 years from middle childhood (age 9 years) to early adulthood (age 29 years)...
October 2016: Journal of Family Psychology: JFP
Alex D Washburne, Joshua W Burby, Daniel Lacker
Systems as diverse as the interacting species in a community, alleles at a genetic locus, and companies in a market are characterized by competition (over resources, space, capital, etc) and adaptation. Neutral theory, built around the hypothesis that individual performance is independent of group membership, has found utility across the disciplines of ecology, population genetics, and economics, both because of the success of the neutral hypothesis in predicting system properties and because deviations from these predictions provide information about the underlying dynamics...
September 2016: PLoS Computational Biology
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