Behavioural plasticity in variable environments

1997 ◽  
Vol 75 (2) ◽  
pp. 161-169 ◽  
Author(s):  
Petr E. Komers
Keyword(s):  
Resource Availability ◽  
Response Curve ◽  
Environmental Variability ◽  
Population Viability ◽  
Behavioural Plasticity ◽  
Behavioural Ecology ◽  
Costs And Benefits ◽  
Behavioural Responses ◽  
Trade Offs ◽  
Variable Environments

The plasticity of behaviour consists of an array of behavioural responses to varying environmental conditions. It is widely predicted that the range of behavioural responses will increase with environmental variability. According to this prediction, the slopes of a response curve representing behavioural plasticity would be identical in environments with different variability. However, the range of behaviours can also increase with the slope of the curve, so that in a given range of environments, the plasticity of behaviour would vary. For example, where two environments are similar in terms of resource availability, the costs of exploiting the resource may differ. An improved ability to assess costs and benefits is predicted to increase behavioural plasticity because it decreases the costs and increases the benefits of alternative behaviours. Moreover, because trade-offs change with age and plasticity is related to trade-offs, plasticity should also change with age. While the ability of animals to adjust to current trade-offs is fundamental for behavioural ecology, demonstration of ranges, slopes, and shapes of plastic behavioural responses is virtually absent from the literature. Knowledge concerning the ability of animals to adjust to environmental fluctuations is important for making predictions about population viability, but empirical evidence is greatly needed to validate current generalizations.

scholarly journals The costs of standardized apprenticeship curricula for training firms

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Jürg Schweri ◽  
Manuel Aepli ◽  
Andreas Kuhn
Keyword(s):  
Regulatory Element ◽  
Recent Survey ◽  
Skills Development ◽  
Costs And Benefits ◽  
Apprenticeship Training ◽  
Training Costs ◽  
Trade Offs ◽  
Training Content ◽  
Productive Process ◽  
Productive Output

AbstractStandardized curricula define the set of skills that must be trained within a training occupation and thus are a key regulatory element of apprenticeship systems. Although clear economic rationales support the usage of such curricula, they necessarily impose costs, especially on firms that train apprentices, but do not use the full set of skills in their productive process and/or train other skills that are not covered by the curriculum. In this paper, we identify the trade-offs involved in setting up training curricula and use data from the most recent survey on the costs and benefits of apprenticeship training among Swiss firms to quantify the associated costs to training firms. On average, training firms state that they do not use 17% of the training content prescribed by the relevant curriculum, and 11% of the companies train additional skills not covered by the curriculum. We show that both kinds of misfit are associated with higher training costs and lower productive output from apprentices. This shows that the regulator imposes costs on firms in order to guarantee broad skills development for apprentices. It also cautions against overly broad curricula that may impose disproportionate costs on firms.

scholarly journals Between Market Failures and Justice Failures: Trade-Offs Between Efficiency and Equality in Business Ethics

2021 ◽  
Author(s):  
Charlie Blunden
Keyword(s):  
Business Ethics ◽  
Private Firms ◽  
Market Failures ◽  
Costs And Benefits ◽  
Trade Offs ◽  
Efficiency Losses ◽  
Different Types ◽  
Hybrid Theory ◽  
Market Failures Approach ◽  
Ethical Obligations

AbstractThe Market Failures Approach (MFA) is one of the leading theories in contemporary business ethics. It generates a list of ethical obligations for the managers of private firms that states that they should not create or exploit market failures because doing so reduces the efficiency of the economy. Recently the MFA has been criticised by Abraham Singer on the basis that it unjustifiably does not assign private managers obligations based on egalitarian values. Singer proposes an extension to the MFA, the Justice Failures Approach (JFA), in which managers have duties to alleviate political, social, and distributive inequalities in addition to having obligations to not exploit market failures. In this paper I describe the MFA and JFA and situate them relative to each other. I then highlight a threefold distinction between different types of obligations that can be given to private managers in order to argue that a hybrid theory of business ethics, which I call the MFA + , can be generated by arguing that managers have obligations based on efficiency and duties based on equality to the extent that these latter obligations do not lead to efficiency losses. This argument suggests a novel theoretical option in business ethics, elucidates the issues that are at stake between the MFA and the JFA, and clarifies the costs and benefits of each theory.

scholarly journals Temperament, Plasticity, and Emotions in Defensive Behaviour of Paca (Mammalia, Hystricognatha)

Animals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 293
Author(s):  
Selene S. C. Nogueira ◽  
Sérgio L. G. Nogueira-Filho ◽  
José M. B. Duarte ◽  
Michael Mendl
Keyword(s):  
Conservation Status ◽  
Behavioural Plasticity ◽  
Affective States ◽  
Defensive Behaviour ◽  
Rapid Adaptation ◽  
Behavioural Responses ◽  
Judgement Bias ◽  
Temperament Dimension ◽  
Ambiguous Cue

Within a species, some individuals are better able to cope with threatening environments than others. Paca (Cuniculus paca) appear resilient to over-hunting by humans, which may be related to the behavioural plasticity shown by this species. To investigate this, we submitted captive pacas to temperament tests designed to assess individual responses to short challenges and judgement bias tests (JBT) to evaluate individuals’ affective states. Results indicated across-time and context stability in closely correlated “agitated”, “fearful” and “tense” responses; this temperament dimension was labelled “restless”. Individual “restless” scores predicted responses to novelty, although not to simulated chasing and capture by humans in a separate modified defence test battery (MDTB). Restless animals were more likely to show a greater proportion of positive responses to an ambiguous cue during JBT after the MDTB. Plasticity in defensive behaviour was inferred from changes in behavioural responses and apparently rapid adaptation to challenge in the different phases of the MDTB. The results indicate that both temperament and behavioural plasticity may play a role in influencing paca responses to risky situations. Therefore, our study highlights the importance of understanding the role of individual temperament traits and behavioural plasticity in order to better interpret the animals’ conservation status and vulnerabilities.

Behavioural responses of Australian freshwater crayfish (Cherax cainii and Cherax albidus) to exotic fish odour

2006 ◽  
Vol 54 (6) ◽  
pp. 399 ◽  
Author(s):  
S. G. Height ◽  
G. J. Whisson
Keyword(s):  
Western Australia ◽  
Predatory Fish ◽  
Behavioural Plasticity ◽  
Current Debate ◽  
Freshwater Crayfish ◽  
Indigenous Species ◽  
Exotic Fish ◽  
Behavioural Responses ◽  
Invasive Crayfish ◽  
Australian Freshwater

Exotic finfish and crayfish have been translocated into Western Australia for more than 100 years. Deliberate stocking and subsequent escape from man-made impoundments have resulted in widespread distribution of non-native yabbies (Cherax albidus) and the exotic redfin perch (Perca fluviatilis) in the State’s south-west. Both species are considered invasive and are known to compete with indigenous species for resources. The nature and degree of impact on native marron (Cherax cainii) is unclear and the subject of current debate. Other researchers have hypothesised that invasive species modify their behaviour in the presence of predators in a more rapid and advantageous manner than native species. This greater behavioural plasticity can result in displacement of indigenous species and successful colonisation of invaders. The aim of this study was to investigate behavioural responses of an indigenous crayfish (C. cainii) and an invasive crayfish (C. albidus) to odours from a native predator (Tandanus bostocki) and an exotic predatory fish (P. fluviatilis) present in Western Australia. Crayfish behaviour was observed in individual glass tanks following the addition of odours from native (T. bostocki) or exotic (P. fluviatilis) finfish predators. Marron exhibited minor behavioural modifications when presented with odours from native or exotic finfish. In contrast, the invasive yabby showed greater detection of odours, displaying significant changes in behaviour (P < 0.05). Yabbies also appeared to distinguish between food odour (commercial crayfish feed) and predator odour; however, neither marron nor yabbies displayed behaviour indicating that they could distinguish between a native or exotic fish predator. Results support the hypothesis that invasive crayfish species have a greater capacity for behavioural plasticity than non-invasive crayfish.

Tales of lizard tails: effects of tail autotomy on subsequent survival and growth of free-ranging hatchling Uta stansburiana

1997 ◽  
Vol 75 (4) ◽  
pp. 542-548 ◽  
Author(s):  
P. H. Niewiarowski ◽  
J. D. Congdon ◽  
A. E. Dunham ◽  
L. J. Vitt ◽  
D. W. Tinkle
Keyword(s):  
Natural Populations ◽  
Reproductive Investment ◽  
Experimental Manipulation ◽  
Costs And Benefits ◽  
Growth And Survival ◽  
Large Sample ◽  
Uta Stansburiana ◽  
Tail Autotomy ◽  
Trade Offs ◽  
Free Ranging

Potential costs and benefits of tail autotomy in lizards have been inferred almost exclusively from experimental study in semi-natural enclosures and from indirect comparative evidence from natural populations. We present complementary evidence of the costs of tail autotomy to the lizard Uta stansburiana from detailed demographic study of a natural population. On initial capture, we broke the tails of a large sample of free-ranging hatchlings (560) and left the tails of another large sample (455) intact, and then followed subsequent hatchling growth and survival over a 3-year period. Surprisingly, in 1 out of the 3 years of study, survival of female hatchlings with broken tails exceeded that of female hatchlings with intact tails. Furthermore, no effects of tail loss on survivorship were detected for male hatchlings. However, in 2 years when recaptures were very frequent (1961, 1962), growth rates of hatchlings with broken tails were significantly slower than those of their counterparts with intact tails. We discuss our results in the broader context of estimating the relative costs and benefits of tail autotomy in natural populations, and suggest that long-term demographic studies will provide the best opportunity to assess realized fitness costs and benefits with minimum bias. We also describe how experimentally induced tail autotomy can be used as a technique to complement experimental manipulation of reproductive investment in the study of life-history trade-offs.

Balancing ecological costs and benefits of fire for population viability of disturbance-dependent butterflies

2017 ◽  
Vol 55 (2) ◽  
pp. 800-809 ◽  
Author(s):  
Norah Warchola ◽  
Elizabeth E. Crone ◽  
Cheryl B. Schultz
Keyword(s):  
Population Viability ◽  
Costs And Benefits

scholarly journals Breaking through evolutionary constraint by environmental fluctuations

2015 ◽  
Author(s):  
Marjon GJ de Vos ◽  
Alexandre Dawid ◽  
Vanda Sunderlikova ◽  
Sander J Tans
Keyword(s):  
Escherichia Coli ◽  
Environmental Variability ◽  
Model System ◽  
Evolutionary Constraint ◽  
Apparent Paradox ◽  
Epistatic Interactions ◽  
Genetic Constraints ◽  
Trade Offs ◽  
Fluctuating Environments ◽  
Genetic Constraint

Epistatic interactions can frustrate and shape evolutionary change. Indeed, phenotypes may fail to evolve because essential mutations can only be selected positively if fixed simultaneously. How environmental variability affects such constraints is poorly understood. Here we studied genetic constraints in fixed and fluctuating environments, using theEscherichia coli lacoperon as a model system for genotype-environment interactions. The data indicated an apparent paradox: in different fixed environments, mutational trajectories became trapped at sub-optima where no further improvements were possible, while repeated switching between these same environments allowed unconstrained adaptation by continuous improvements. Pervasive cross-environmental trade-offs transformed peaks into valleys upon environmental change, thus enabling escape from entrapment. This study shows that environmental variability can lift genetic constraint, and that trade-offs not only impede but can also facilitate adaptive evolution.

scholarly journals Behavioural effects of temperature on ectothermic animals: unifying thermal physiology and behavioural plasticity

2016 ◽  
Author(s):  
Paul K. Abram ◽  
Guy Boivin ◽  
Joffrey Moiroux ◽  
Jacques Brodeur
Keyword(s):  
Future Research ◽  
Behavioural Plasticity ◽  
Behavioural Ecology ◽  
Behavioural Thermoregulation ◽  
Unified Framework ◽  
Behavioural Changes ◽  
Behavioural Effects ◽  
Effects Of Temperature ◽  
Kinetic Effects

AbstractTemperature imposes significant constraints on ectothermic animals, and these organisms have evolved numerous adaptations to respond to these constraints. While the impacts of temperature on the physiology of ectotherms have been extensively studied, there are currently no frameworks available that outline the multiple and often simultaneous pathways by which temperature can affect behaviour. Drawing from the literature on insects, we propose a unified framework that should apply to all ectothermic animals, generalizing temperature's behavioural effects into (1) Kinetic effects, resulting from temperature's bottom-up constraining influence on metabolism and neurophysiology over a range of timescales (from short-to long-term), and (2) Integrated effects, where the top-down integration of thermal information intentionally initiates or modifies a behaviour (behavioural thermoregulation, thermal orientation, thermosensory behavioural adjustments). We discuss the difficulty in distinguishing adaptive behavioural changes due to temperature from behavioural changes that are the products of constraints, and propose two complementary approaches to help make this distinction and class behaviours according to our framework: (i) behavioural kinetic null modeling and (ii) behavioural ecology experiments using temperature-insensitive mutants. Our framework should help to guide future research on the complex relationship between temperature and behaviour in ectothermic animals.

scholarly journals Temperature as a modulator of sexual selection

2018 ◽  
Author(s):  
Roberto García-Roa ◽  
Francisco Garcia-Gonzalez ◽  
Daniel W.A. Noble ◽  
Pau Carazo
Keyword(s):  
Global Warming ◽  
Sexual Selection ◽  
Thermal Environment ◽  
Abiotic Factors ◽  
Meta Analysis ◽  
Population Viability ◽  
Order Effects ◽  
Secondary Sexual Traits ◽  
Trade Offs ◽  
Wide Range

A central question in ecology and evolution is to understand why sexual selection varies so much in strength across taxa, and it has long been known that ecological factors are crucial to this respect. Temperature is a particularly critical abiotic ecological factor that can drastically modulate a wide range of physiological, morphological and behavioural traits, impacting individuals and populations at a global taxonomic scale. Furthermore, temperature exhibits substantial temporal variation (e.g. daily, seasonally and inter-seasonally), and hence for most species in the wild sexual selection will regularly unfold in a dynamic thermal environment. Unfortunately, studies have so far almost completely neglected the role of temperature as a modulator of sexual selection. Here, we outline the main pathways via which temperature can affect the intensity and form (i.e. mechanisms) of sexual selection, via: a) direct effects on secondary sexual traits and preferences (i.e. trait variance, opportunity for selection and trait-fitness covariance), and b) indirect effects on key mating parameters, sex-specific reproductive costs/benefits, trade-offs, demography and correlated abiotic factors. Building upon this framework, we show that, by focusing exclusively on the first order effects that environmental temperature has on traits linked with individual fitness and population viability, current global warming studies may be ignoring important eco-evolutionary feedbacks mediated by sexual selection. Finally, we tested the general prediction that temperature modulates sexual selection by conducting a meta-analysis of available studies experimentally manipulating temperature and reporting effects on the variance of male/female reproductive success and/or traits under sexual selection. Our results show a clear association between temperature and sexual selection measures in both sexes. In short, we suggest that studying the feedback between temperature and sexual selection processes can be vital to better understand variation in the strength of sexual selection in nature, and its consequences for population viability in response to environmental change (e.g. global warming).

Water-Energy-Food Nexus Review for Biofuels Assessment

2021 ◽  
Vol 11 (1) ◽  
pp. 193-205
Author(s):  
Abass A. Gazal ◽  
Napat Jakrawatana ◽  
Thapat Silalertruksa ◽  
Shabbir H. Gheewala
Keyword(s):  
Resource Availability ◽  
First Generation ◽  
Decision Makers ◽  
Assessment Methodology ◽  
Life Cycle Assessment Methodology ◽  
New Approach ◽  
Future Studies ◽  
Human Needs ◽  
Trade Offs ◽  
Basic Human Needs

The appropriate use of limited natural resources for generating basic human needs such as energy, food, and water, is essential to help the society function efficiently. Hence, a new approach called nexus is being considered to resolve the effects of intrinsic trade-offs between the essential needs. A review of different methods and frameworks of the water-energy-food nexus was done in this article to give a detailed repository of information on existing approaches and advocate the development of a more holistic quantitative nexus method. Assessing biofuels under the water-energy-food nexus perspective, this review addresses the sustainability of bioenergy production. The results show the countries that can sustainably produce first-generation biofuels. Only a few methods have varied interdisciplinary procedures to analyse the nexus, and more analytical software and data on resource availability/use are needed to address trade-offs between these interacting resource sectors constituting the nexus. Also, “land” is suggested as an additional sector to consider in future studies using both the nexus index and life cycle assessment methodology. The review reveals that to tackle composite challenges related to resource management, cross-disciplinary methods are essential to integrate environmental, socio-political facets of water, energy, and food; employ collaborative frameworks; and seek the engagement of decision-makers.

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