577 research outputs found

    Toward a Global Regime of Vessel Anti-Fouling

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    Vessel anti-fouling is key to the efficient operation of ships, and essential for effective control of invasive species introduced through international shipping. Anti-Fouling Systems, however, pose their own threats to marine environments. The Anti-Fouling Convention of 2001 banned the use of organotin compounds such as Tributyltin, and created a system for adoption of alternative anti-fouling biocides. In 2011, the Marine Environmental Protection Committee of the International Maritime Organization (IMO) released guidelines on bio-fouling management record keeping, installation, inspection, cleaning, maintenance, design and construction. Though these Guidelines provide a template for more effective and environmentally sound anti-fouling control and implementation, they are not mandatory. This article proposes that the member states of the IMO adopt the 2011 Guidelines as a mandatory instrument

    Improving Measurement of Ambiguity Tolerance Among Teacher Candidates

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    The process of learning often requires dealing with the ambiguity of uncertain interpretations. A learner’s tolerance for ambiguity involves the degree of willingness to accept or adapt to unfamiliar, unpredictable, or uncertain situations and ideas. This study examined the measurement of ambiguity tolerance (AT) among teacher candidates. Pre-service teachers (n = 114) attending a medium size university in the southeastern United States were administered McLain\u27s (1993) Multiple Stimulus Types Ambiguity Tolerance (MSTAT-I) scale. Analyses were first conducted on item responses from the MSTAT-I, then on item responses from the MSTAT-II (McLain, 2009), an instrument comprised of a subset of 13 particular items from the original 22-item instrument.Rasch-model measures and diagnostic analyses were compared and illustrated graphically for the two versions of the AT instrument and then for two shorter versions. Findings indicated validity support for the MSTAT-II instrument, measurement improvement to reducing the number of Likert scale categories to 5, and further measurement benefits of an alternative 9-item AT instrument. The distribution of measured AT among participants was discussed with regard to individual differences among teacher candidates and the potential application of AT measurement as an intellectual disposition among educators

    Sequential Social Experiences Interact to Modulate Aggression but Not Brain Gene Expression in the Honey Bee (\u3cem\u3eApis mellifera\u3c/em\u3e)

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    Background: In highly structured societies, individuals behave flexibly and cooperatively in order to achieve a particular group-level outcome. However, even in social species, environmental inputs can have long lasting effects on individual behavior, and variable experiences can even result in consistent individual differences and constrained behavioral flexibility. Despite the fact that such constraints on behavior could have implications for behavioral optimization at the social group level, few studies have explored how social experiences accumulate over time, and the mechanistic basis of these effects. In the current study, I evaluate how sequential social experiences affect individual and group level aggressive phenotypes, and individual brain gene expression, in the highly social honey bee (Apis mellifera). To do this, I combine a whole colony chronic predator disturbance treatment with a lab-based manipulation of social group composition. Results: Compared to the undisturbed control, chronically disturbed individuals show lower aggression levels overall, but also enhanced behavioral flexibility in the second, lab-based social context. Disturbed bees display aggression levels that decline with increasing numbers of more aggressive, undisturbed group members. However, group level aggressive phenotypes are similar regardless of the behavioral tendencies of the individuals that make up the group, suggesting a combination of underlying behavioral tendency and negative social feedback influences the aggressive behaviors displayed, particularly in the case of disturbed individuals. An analysis of brain gene expression showed that aggression related biomarker genes reflect an individual’s disturbance history, but not subsequent social group experience or behavioral outcomes. Conclusions: In highly social animals with collective behavioral phenotypes, social context may mask underlying variation in individual behavioral tendencies. Moreover, gene expression patterns may reflect behavioral tendency, while behavioral outcomes are further regulated by social cues perceived in real-time

    Ecosystem Restoration: Enhancing Ecosystem Services with Floating Aquaculture

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    Restoration ecologists recognize the need for restoring ecosystem servicesin sustainable ways that meet societal needs. In the UK, Ireland, Australia,and some US states the goal is restoring native oyster reefs. In otherstates, failures at restoration due to poor water quality and predation havefocused restoration activities on techniques that work, restoring intertidalreefs and generating living shorelines that reduce or reverse erosion. In theUnited States, restoring water quality and reducing or reversing erosion aresocietally accepted entry points for repairing estuarine ecosystems. Thisstudy is an overview of the current status of oyster reef restoration andprovide a novel approach called “oyster reef in a bag”. Combining oysterreef restoration efforts with existing floating oyster aquaculture technologygenerates novel ecosystems that are a combination of biofouling and oysterreef communities. These novel ecosystems could be a practical beginningto improve water quality, mitigate erosion and restore higher trophic levelecosystem services

    Ocean acidification affects marine chemical communication by changing structure and function of peptide signalling molecules

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    Ocean acidification is a global challenge that faces marine organisms in the near future with a predicted rapid drop in pH of up to 0.4 units by the end of this century. Effects of the change in ocean carbon chemistry and pH on the development, growth and fitness of marine animals are well documented. Recent evidence also suggests that a range of chemically mediated behaviours and interactions in marine fish and invertebrates will be affected. Marine animals use chemical cues, for example, to detect predators, for settlement, homing and reproduction. But while effects of high COâ‚‚ conditions on these behaviours are described across many species, little is known about the underlying mechanisms, particularly in invertebrates. Here we investigate the direct influence of future oceanic pH conditions on the structure and function of three peptide signalling molecules with an interdisciplinary combination of methods. NMR spectroscopy and quantum chemical calculations were used to assess the direct molecular influence of pH on the peptide cues and we tested the functionality of the cues in different pH conditions using behavioural bioassays with shore crabs (Carcinus maenas) as a model system. We found that peptide signalling cues are susceptible to protonation in future pH conditions, which will alter their overall charge. We also show that structure and electrostatic properties important for receptor-binding differ significantly between the peptide forms present today and the protonated signalling peptides likely to be dominating in future oceans. The bioassays suggest an impaired functionality of the signalling peptides at low pH. Physiological changes due to high COâ‚‚ conditions were found to play a less significant role in influencing the investigated behaviour. From our results we conclude that the change of charge, structure and consequently function of signalling molecules presents one possible mechanism to explain altered behaviour under future oceanic pH conditions

    Advancing Behavioural Genomics by Considering Timescale

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    Animal behavioural traits often covary with gene expression, pointing towards a genomic constraint on organismal responses to environmental cues. This pattern highlights a gap in our understanding of the time course of environmentally responsive gene expression, and moreover, how these dynamics are regulated. Advances in behavioural genomics explore how gene expression dynamics are correlated with behavioural traits that range from stable to highly labile. We consider the idea that certain genomic regulatory mechanisms may predict the timescale of an environmental effect on behaviour. This temporally minded approach could inform both organismal and evolutionary questions ranging from the remediation of early life social trauma to understanding the evolution of trait plasticity

    Insects Provide Unique Systems to Investigate How Early-Life Experience Alters the Brain and Behavior

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    Early-life experiences have strong and long-lasting consequences for behavior in a surprising diversity of animals. Determining which environmental inputs cause behavioral change, how this information becomes neurobiologically encoded, and the functional consequences of these changes remain fundamental puzzles relevant to diverse fields from evolutionary biology to the health sciences. Here we explore how insects provide unique opportunities for comparative study of developmental behavioral plasticity. Insects have sophisticated behavior and cognitive abilities, and they are frequently studied in their natural environments, which provides an ecological and adaptive perspective that is often more limited in lab-based vertebrate models. A range of cues, from relatively simple cues like temperature to complex social information, influence insect behavior. This variety provides experimentally tractable opportunities to study diverse neural plasticity mechanisms. Insects also have a wide range of neurodevelopmental trajectories while sharing many developmental plasticity mechanisms with vertebrates. In addition, some insects retain only subsets of their juvenile neuronal population in adulthood, narrowing the targets for detailed study of cellular plasticity mechanisms. Insects and vertebrates share many of the same knowledge gaps pertaining to developmental behavioral plasticity. Combined with the extensive study of insect behavior under natural conditions and their experimental tractability, insect systems may be uniquely qualified to address some of the biggest unanswered questions in this field

    Quantitative modelling biology undergraduate assessment

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    The Quantitative Modelling Biology Undergraduate Assessment (QM BUGS Version II) assesses undergraduate biology students’ quantitative modelling abilities and confidence. The assessment is intended to be given in undergraduate biology courses where instructors are engaging students in quantitative modelling within biological contexts. The assessment consists of 36 questions: 25 multiple choice questions addressing four subcategories within quantitative modelling understanding (Quantitative Act, Quantitative Interpretation, Quantitative Modelling, and Meta-Modelling) and 11 Likert questions addressing student confidence about modelling in biology within the four subcategories. QM BUGS assessments were piloted in multiple undergraduate biology courses at both a research intensive university and regional university in fall 2017 (QM BUGS I) and spring 2018 (QM BUGS II). Here we present the development and theoretical framework for the assessment, focusing upon reliability and validity evidence with respect to measures of student understanding and student confidence following administration of the QM BUGS II

    Mitochondrial Haplotypes suggest Genetic Component for Habitat Preference in Blue Crabs

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    Atlantic blue crabs (Callinectes sapidus) are ecologically and commercially fundamental. Life stages are punctuated with migration. Adults and juveniles live in estuaries and sounds. Larval stages develop in the coastal ocean. Juvenile and adult crabs occupy habitats from high salinities to fresh water. We determined whether maturing juvenile and adult blue crab habitat use is reflected in mitochondrial cytochrome oxidase 1 haplotypes. High salinity crabs had lower haplotype diversity (0.7260 ± .03900) compared to spawning crabs (0.9841 ± .00021) and low salinity crabs (0.94154 ± .00118). Significant pairwise differences in haplotypes were found between high salinity and spawning crabs (Nm = 0.26018, p < 0.001), and between high salinity and low salinity crabs (Nm = 0.19482, p < 0.001) indicating a lack of gene flow. Crabs from high salinity had highly significant genetic differentiation compared to spawning crabs (Fst = 0.11830, p < 0.001) and low salinity crabs (Fst = 0.09689, p < 0.001). Results support the hypothesis that genetics influence habitat selection. Crab larvae mix in the coastal ocean but occupy specific habitats upon return to sounds and estuaries. These findings have implications for the management of fisheries

    Assessing quantitative modelling practices, metamodelling, and capability confidence of biology undergraduate students

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    Quantitative modelling plays an important role as biology increasingly deals with big data sets, relies on modelling to understand system dynamics, makes predictions about impacts of changes, and revises our understanding of system interactions. An assessment of quantitative modelling in biology was administered to students (n = 612) in undergraduate biology courses at two universities to provide a picture of student ability in quantitative reasoning within biology and to determine how capable those students felt about this ability. A Rasch analysis was used to construct linear measures and provide validity evidence for the assessment and to examine item statistics on the same scale as student ability measures. Students overall had greater ability in quantitative literacy than in quantitative interpretation of models or modelling. There was no effect of class standing (Freshmen, Sophomore, etc.) on student performance. The assessment showed that students who participated felt confidence in their ability to quantitatively model biological phenomena, even while their performance on ability questions were low. Collectively modelling practices were correlated with students’ metamodelling knowledge and not correlated with students’ modelling capability confidence. Biology instructors who incorporate the process of modelling into their courses may see improved abilities of students to perform on quantitative modelling tasks
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