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Host plants are an important selective factor for the evolution of reproductive traits in herbivorous insects. Among different host plants, offspring will be exposed to different environmental conditions, and parents are expected to allocate reproductive resources adaptively to their offspring according to such environmental heterogeneity. Elasmucha putoni Scott (Hemiptera: Acanthosomatidae) is a bivoltine shield bug showing maternal care. We examined the variation in reproductive traits, that is, egg size, clutch size and the trade‐off between them, between two generations of a population and two populations of the same (later) generation, which differ in their host plants. Controlling for female body size, a significant difference was detected in egg size, but not in clutch size between the earlier generation on Morus australis and the later one on Euptelea polyandra or Rosa multiflora. Moreover, there was no difference in the two traits between the populations (one using E. polyandra and another using R. multiflora) of the same generation. A significant trade‐off between egg size and clutch size was detected in the earlier generation on M. australis but not in the later generation on E. polyandra or R. multiflora. This is the first study indicating variable reproductive allocation according to different host plants in herbivorous insects with maternal care. [ABSTRACT FROM AUTHOR]

In federated learning, benign participants aim to optimize a global model collaboratively. However, the risk of privacy leakage cannot be ignored in the presence of semi-honest adversaries. Existing research has focused either on designing protection mechanisms or on inventing attacking mechanisms. While the battle between defenders and attackers seems never-ending, we are concerned with one critical question: Is it possible to prevent potential attacks in advance? To address this, we propose the first game-theoretic framework that considers both FL defenders and attackers in terms of their respective payoffs, which include computational costs, FL model utilities, and privacy leakage risks. We name this game the federated learning privacy game (FLPG), in which neither defenders nor attackers are aware of all participants' payoffs. To handle the incomplete information inherent in this situation, we propose associating the FLPG with an oracle that has two primary responsibilities. First, the oracle provides lower and upper bounds of the payoffs for the players. Second, the oracle acts as a correlation device, privately providing suggested actions to each player. With this novel framework, we analyze the optimal strategies of defenders and attackers. Furthermore, we derive and demonstrate conditions under which the attacker, as a rational decision-maker, should always follow the oracle's suggestion not to attack. [ABSTRACT FROM AUTHOR]

Reproductive allocation and cost play a crucial role in the survival of organisms, but research on these traits in bryophytes has been limited and inconsistent. To address this, we conducted a literature review focusing on bryophyte studies. Our goal was to clarify inconsistencies and explore reproductive allocation and cost concepts, as well as current trends in bryophyte reproduction. We examined different approaches and highlighted advantages and limitations. We emphasized five key topics: the importance of understanding reproductive allocation and reproductive cost in bryophytes; the significance of bryophytes as model organisms; historical research; terminological and methodological inconsistencies; sexual dimorphism and reproductive allocation; and measurement methods. Furthermore, we provided insights into future perspectives. Based on our findings, we advocate for standardized quantification of reproductive allocation. Standardization would enhance comparability and synthesis of results, ultimately advancing our understanding of reproductive allocation and cost of reproduction in bryophytes. [ABSTRACT FROM AUTHOR]

Trade‐off conflicts among the Sustainable Development Goals have been a challenge. To reconcile frictional relationships among food production security (Goal 2), water use efficiency (Goal 6), and climate change mitigation (Goal 13), an empirical examination using deterministic frontier analysis was conducted globally. A single volume‐based index for each goal is too simple to evaluate the agricultural sustainability of different areas from the nexus assessment perspective. Our major findings are threefold. First, approximately two‐thirds of African countries have suffered from small food production and excess water use. Second, marked contrasts are observed in the possibilities of an increase in food production and reduction in water use and CO2 emissions among regions. Asian countries use water efficiently, whereas countries in the western regions control CO2 emissions. Third, trade‐offs among food production, water use, and CO2 emissions in agriculture are observed. It is almost impossible to reduce water use in Asia and CO2 emissions in the western regions for food production security. Based on the nexus approach, local strategies need to be compatible with global sustainability. Future research should identify the factors that determine the agricultural efficiency to devise local strategies, and develop policies simultaneously pursuing relevant environmental and well‐being goals. [ABSTRACT FROM AUTHOR]

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Regeneration has been a topic of interest across a range of taxa for centuries, and arthropods are no exception. Trade‐offs associated with regeneration are likely to involve the reallocation of resources away from other metabolic activities such as growth, development or reproduction. This might be reflected in costs to some developmental traits of the organism, despite regeneration being advantageous. These associated costs might also differ with the stage of injury or amputation. Here, we hypothesise that the extent of regeneration and trade‐offs associated with it may be stage‐specific. To test this hypothesis, the right forelimb of four larval stages of the ladybird beetle Cheilomenes sexmaculata (Fabricius) (Coleoptera: Coccinellidae) was amputated. Amputated individuals were reared until adulthood, and all developmental transitions were recorded. Regenerated legs in all the treatments were smaller than the controls, which did not experience the amputation, and the regenerative potency of early larval stages was higher than that of late larval stages. Limb regeneration caused delays in post‐amputation developmental duration in all the treatments, increasing their total developmental period. The length of the unamputated left foreleg as well as the wing and antenna size were also reduced in regenerated beetles, showing some internal trade‐off. However, there were no significant differences observed between regenerated and control adults in their fresh body weight and body size. Thus, limb regeneration depends upon the stage of larval development at which the amputation was performed. Amputation also affects the development of other appendages. The delay in normal beetle development might have been observed because of extra resource requirement, their allocation as well as reprogramming of the expression of some genes during regeneration. [ABSTRACT FROM AUTHOR]

An understanding of biological fitness is central to theory and practice in ecology and evolution, yet fitness remains an elusive concept to define and is challenging to measure accurately. Fitness reflects an individual's ability to pass its alleles on to subsequent generations. Researchers often quantify proxies for fitness, such as survival, growth, or reproductive success. However, it can be difficult to determine lifetime fitness, especially for species with long life spans. The abiotic and biotic environment strongly affects the expression of fitness, which means that fitness components can vary through both space and time. This spatial and temporal heterogeneity results in the impressive range of adaptations that we see in nature. Here, we review definitions of fitness and approaches to measuring fitness at the level of genes, individuals, genotypes, and populations and highlight that fitness is a key concept linking ecological and evolutionary thought. [ABSTRACT FROM AUTHOR]

This study proposes an optimization model based on particle swarm optimization (PSO) to achieve the objectives of minimizing project duration, project cost, and resource fluctuation while maximizing project quality and schedule flexibility. The objectives of this study are as follows: (1) to determine whether the interrelationships between these five objectives affect the outcome of the optimization; (2) to determine whether the presence or absence of resource constraints affects the solution; and (3) to verify that the solution of the PSO-based optimization model coincides with the exact mathematical solution, but faster. An example project was presented to illustrate the applicability of the proposed model. The conclusions of this study are as follows: (1) multiple objectives do interact with each other and should be evaluated simultaneously rather than one at a time to reach realistic solutions, (2) resource constraints do affect the solutions obtained, and (3) the proposed model successfully reaches an optimal solution that is extremely close to the exact mathematical solution much faster than the mathematical model. [ABSTRACT FROM AUTHOR]

Fog computing has emerged as a decentralized computing paradigm that extends cloud services to the network edge, enabling faster data processing and real-time applications. The increasing popularity of fog computing has led to the emergence of a potential market involving users and providers of fog resources. However, both parties are driven by self-interest and seek to maximize their utility, giving rise to multiple conflicts extending beyond mere price considerations. Negotiations can play a crucial role in resolving conflicts and establishing mutually beneficial service level agreements. Moreover, in the heterogeneous fog environment, quality of service attributes, such as throughput, delay, trust, power dissipation, etc., vary significantly among different user-fog associations. These attributes, although non-negotiable, hold great importance for entities and directly influence partner selection. Entities may exhibit a preference for one another based on these non-negotiable attributes. To the best of our knowledge, no existing literature specifically addresses the issue of associating with a preferred trading partner at a negotiated value for multiple issues in the fog environment. This research aims to address this gap and provide insights into this unexplored area. This work presents a novel Preference-based Muti-Issue Negotiation Algorithm, PMINA, for many to many, bilateral and concurrent negotiations in the fog environment. The results confirm the significance of PMINA, demonstrating a substantial enhancement in user and fog utilities. [ABSTRACT FROM AUTHOR]

In the presented paper, we investigate efficient solutions to optimization problems with multiple criteria and bounded trade-offs. A nonlinear optimization problem to find the relationships between the upper bound for trade-offs and objective functions is presented. Due to this problem, we determine some properly efficient points that are closer to the ideal point. To this end, we apply the extended form of the generalized Tchebycheff norm. Note that all the presented results work for general problems and no convexity assumption is needed. [ABSTRACT FROM AUTHOR]

One of the main concerns about fairness in machine learning (ML) is that, in order to achieve it, one may have to trade off some accuracy. To overcome this issue, Hardt et al. (Adv Neural Inf Process Syst 29, 2016) proposed the notion of equality of opportunity (EO), which is compatible with maximal accuracy when the target label is deterministic with respect to the input features. In the probabilistic case, however, the issue is more complicated: It has been shown that under differential privacy constraints, there are data sources for which EO can only be achieved at the total detriment of accuracy, in the sense that a classifier that satisfies EO cannot be more accurate than a trivial (i.e., constant) classifier. In this paper, we strengthen this result by removing the privacy constraint. Namely, we show that for certain data sources, the most accurate classifier that satisfies EO is a trivial classifier. Furthermore, we study the admissible trade-offs between accuracy and EO loss (opportunity difference) and characterize the conditions on the data source under which EO and non-trivial accuracy are compatible. [ABSTRACT FROM AUTHOR]

Companies are increasingly focusing on sustainable business practices. Internal and external stakeholders' expectations manifest in legal requirements, national and international standards, and market and customer expectations, among other things, must be considered. In addition to profit maximization, which is the usual target for corporate management, management must consider environmental sustainability aspects such as resource efficiency, greenhouse gas intensity, and a company's emissions behavior. In addition, social aspects related to the company's employees, the immediate urban environment, the situation in the supply chain, and effects on the market environment must increasingly be considered. Specifically, companies are faced with the challenge of dealing with conflicting objectives regarding the various aspects of sustainability and, if necessary, weighing them up against each other. These trade-offs must be made against the company's socio-economic and ecological environment, corporate strategy, and sustainability goals. This paper provides an overview of current approaches and research gaps on this topic through a literature review. It highlights the lack of methods and frameworks to specifically deal with trade-offs and conflicts between goals. [ABSTRACT FROM AUTHOR]

Phthalate esters (PAEs) raised serious concerns on their health risk due to their toxicities. However, toxicities of low‐molecular‐weight PAEs, for example, dimethyl phthalates (DMPs), remained poorly investigated. In the present study, the reproductive toxicities of dimethyl (o‐)phthalate (DMOP), dimethyl (p‐)phthalate (DMPP), and dimethyl (m‐)phthalate (DMMP) were measured on Caenorhabditis elegans with mechanical exploration. Results showed that DMPP, DMOP, and DMMP commonly inhibited the total reproduction while stimulated lifespan, showing trade‐off effects. In effects on gene expressions, DMPP, DMOP, and DMMP caused different regulations on the expressions of vab‐1, ceh‐18, and gsa‐1 which are involved in oocyte growth, ovulation, and maturation. Meanwhile, they commonly downregulated those of rme‐2 and rcy‐4 that regulate germ cells and gonads and lipid metabolism in oocytes. Moreover, the effects on biochemicals that regulate reproductive processes showed alteration between stimulation and inhibition over life stages. In addition, effects at apical, biochemical, and molecular levels clearly showed the structure influences on the toxicities. Summing up, reproductive toxicities of DMPs depended on the exposure life stages and also the chemical structures. [ABSTRACT FROM AUTHOR]

Land use planning (LUP) to achieve Land Degradation Neutrality (LDN) needs methods and tools that support the identification of best LUP solutions in terms of transitions from current degradative land use (LU) and land management (LM) practices to better LU and LM options. A crucial need is the identification of context specific sustainable land management (SLM) options. Addressing this need must aim at not only reversing/recovering past degradation (e.g., via restoration or rehabilitation in land degradation hotspots), but also avoiding "new" degradation possibly caused by unsuitable LU and LM. This requires SLM planning based on anticipated impact assessment of the LU‐LM transition scenarios set to achieve LDN, which can be achieved through a participatory planning process that integrates interests/needs and knowledge of stakeholders with science‐based supportive tools to identify rational, plausible, and socially relevant options. The geoinformatics Land Use Planning for LDN (LUP4LDN) conceptual procedure and tool have been designed for this purpose. Their aim is to support national and subnational planners by (i) mapping geographic patterns of past land degradation (LD) utilizing the LDN indicators adopted by the UNCCD (SDG 15.3.1 indicator) for user‐defined regions of interest (RoI); (ii) helping users anticipate future LD by identifying land that is unsustainably managed and that will likely become degraded during the planning period; (iii) partitioning the LD areas into spatial domains of socio‐ecological contextual similarity (i.e., contextual similarity units) to which the LU‐LM transitional options will be fitted; and (iv) providing an interactive procedure for participatory LU‐LM transitional scenario development over selected contextual similarity units and timeframes. LUP4LDN uses the Global Database of the World Overview of Conservation Approaches and Technologies (WOCAT), ICARDA's Geoinformatics Options by Context (GeOC) tool, and ELD (Economics of Land Degradation) indicators to identify context‐relevant SLM that are available in the RoI, suggests candidate SLM options, and visualizes related expected levels of impacts on ecosystem services via maps and graphs. The generated maps inform users about trade‐offs upon which users can discuss or negotiate transitional pathways. LUP4LDN has been codeveloped with national stakeholders in Tunisia and Burkina Faso. The piloting implementation in the two countries assessed how LUP4LDN fits with existing LUP processes and the benefits achieved by using the tool to support LUP for LDN. [ABSTRACT FROM AUTHOR]

Tracy and Robins (Psychological Inquiry, 15(2), 103–125, 2004) theorized that there are two facets of pride: authentic (e.g., "accomplished") and hubristic (e.g., "arrogant"). While these facets are assumed to function simultaneously over time, it remains unclear whether they differ by gender, given that pride is associated with various social behaviors (Magee Journal of Happiness Studies, 16(5), 1091–1115, 2015; Yeung & Shen Journal of Organizational Behavior, 40(6), 605–624, 2019). In this study, we recruited 118 U.S. college students (54.2% female; 49.18% Non-Hispanic White; mean age = 19.12 years) who participated in a group discussion task and reported their levels of authentic and hubristic pride at three-time points. We used the Repeated-Measures Actor-Partner Interdependence Model (RM-APIM, Kenny et al., 2006) and calculated two change scores (e.g., T2 - T1) as outcomes for the dependent variables. We also graphed the topological state of each facet of pride simultaneously (Butner et al. Psychological Methods, 20, 1–25, 2015). Our findings suggest that: (1) both facets significantly predicted their stability over time for both genders, and (2) females had a lower value of authentic pride but reached stability in authentic pride more quickly than males. These results suggest that females may be more quickly guided by what they perceive as socially expected behavior by themselves and others in authentic pride, even at lower values. In contrast, males may prioritize maintaining higher levels of authentic pride over quickly responding to social cues. [ABSTRACT FROM AUTHOR]

Ungulates commonly select habitat with higher forage biomass and or nutritional quality to improve body condition and fitness. However, predation risk can alter ungulate habitat selection and foraging behavior and may affect their nutritional condition. Ungulates often choose areas with lower predation risk, sometimes sacrificing higher quality forage. This forage-predation risk trade-off can be important for life history strategies and influences individual nutritional condition and population vital rates. We used GPS collar data from adult female mule deer (Odocoileus hemionus) and mountain lions (Puma concolor) to model mule deer habitat selection in relation to forage conditions, stalking cover and predation risk from mountain lions to determine if a forage-predation risk trade-off existed for mule deer in central New Mexico. We also examined mountain lion kill sites and mule deer foraging locations to assess trade-offs at a finer scale. Forage biomass and protein content were inversely correlated with horizontal visibility, hence associated with higher stalking cover for mountain lions, suggesting a forage-predation risk trade-off for mule deer. Mule deer habitat selection was influenced by forage biomass and protein content at the landscape and within home range spatial scales, with forage protein being related to habitat selection during spring and summer and forage biomass during winter. However, mule deer selection for areas with better foraging conditions was constrained by landscape-scale encounter risk for mountain lions, such that increasing encounter risk was associated with diminished selection for areas with better foraging conditions. Mule deer also selected for areas with higher visibility when mountain lion predation risk was higher. Mountain lion kill sites were best explained by decreasing horizontal visibility and available forage protein, suggesting that deer may be selecting for forage quality at the cost of predation risk. A site was 1.5 timesmore likely to be a kill site with each 1-meter decrease in visibility (i.e., increased stalking cover). Mule deer selection of foraging sites was related to increased forage biomass, further supporting the potential for a trade-off scenario. Mule deer utilized spatio-temporal strategies and risk-conditional behavior to reduce predation risk, and at times selected suboptimal foraging areas with lower predation risk. [ABSTRACT FROM AUTHOR]

Common bean is often considered a woman's crop because they play important roles from production to marketing. However, breeding programs often focus on farmers without adequate attention to the interconnectedness between gender and other socioeconomic variables and how they influence varietal and trait preferences of other value chain actors. This study analyzed gendered differences in bean production and trade, implications of socioeconomic conditions on bean production and marketing, and the role of partnerships in closing gender gaps in the bean value chain in Zimbabwe. The results obtained from the analysis of survey data collected from 131 farmers and 18 trades revealed beans as a dual-purpose crop for male and female farmers and traders. Varietal and trait preferences were the same for both male and female farmers and traders but were prioritized differently. While female farmers prioritized cooking time, men farmers prioritized biofortification and market traits. Whereas male traders equally preferred price, color, and appearance, female traders prioritized price over color and appearance. Poverty and marital statuses of respondents influenced the number of varieties preferred by male and female farmers. We found that the effectiveness of partnerships in closing gender gaps in marketing is variety specific. While having partners closed the gender gaps in the marketing of the NUA45 variety, such partnerships did not have the same effect on closing gender gaps in the marketing of Cherry, Gloria, and other varieties. The results show that considering socioeconomic characteristics of actors and partnerships can reduce gender disparities in the bean value chain. Therefore, breeding programs should recognize the interconnectedness between socioeconomic variables and gender when developing breeding products. [ABSTRACT FROM AUTHOR]

Plants inhabit stressful environments characterized by a variety of stressors, including mine sites, mountains, deserts, and high latitudes. Populations from stressful and reference (non‐stressful) sites often have performance differences. However, while invasive and native species may respond differently to stressful environments, there is limited understanding of the patterns in reaction norms of populations from these sites. Here, we use phylogenetically controlled meta‐analysis to assess the performance of populations under stress and non‐stress conditions. We ask whether stress populations of natives and invasives differ in the magnitude of lowered performance under non‐stress conditions and if they vary in the degree of performance advantage under stress. We also assessed whether these distinctions differ with stress intensity. Our findings revealed that natives not only have greater adaptive advantages but also more performance reductions than invasives. Populations from very stressful sites had more efficient adaptations, and performance costs increased with stress intensity in natives only. Overall, the results support the notion that adaptation is frequently costless. Reproductive output was most closely associated with adaptive costs and benefits. Our study characterized the adaptive strategies used by invasive and native plants under stressful conditions, thereby providing important insights into the limitations of adaptation to extreme sites. [ABSTRACT FROM AUTHOR]

Whether the heat and cold tolerance of endotherms evolve independently or correlatively remains unresolved. Both physiological trade-offs and natural selection can contribute to a coevolutionary pattern of heat and cold tolerance in endotherms. Using a published database, we tested the correlation between upper and lower thermal limits across endothermic species with multi-response generalized linear mixed models incorporating phylogenies. We found a positive correlation between upper and lower thermal limits, which suggested a coevolutionary pattern of heat and cold tolerance. Specifically, this relationship between heat and cold tolerance is phylogenetically constrained for tropical endotherms but not for temperate endotherms. The correlated evolution between heat and cold tolerance may have a significant influence on endotherms' evolution and ecology and needs to be further investigated. [ABSTRACT FROM AUTHOR]

Thermal acclimation is often considered critical in organismal responses to novel thermal conditions. Our understanding of the physiological implications of acclimation is largely derived from lab studies that either manipulate daytime basking availability or use of constant thermal regimes. In contrast, the importance of the nocturnal thermal environment (e.g. the extent of thermal respite) is often overlooked yet could play a vital role in thermal acclimation in the wild.To fill this gap, we acclimated lizards (Amphibolurus muricatus) under three thermal regimes (Hot Constant, Cold Constant and Alternating) and compared their physiological responses (Metabolic Rate, Sprint Speed, Thermal Preferences and Thermal Limits).We found that animals maintained constantly at hot temperatures (preferred temperature, 35°C) gained sprint performance increases and exhibited shifts in thermal optima not seen in those maintained constantly at cold temperatures (20°C), yet suffered costs to growth (in smaller animals) and maintenance (mass loss in larger animals). Animals maintained at alternating temperatures (12 h 20°C; 12 h 35°C) had performance benefits similar to animals in the hot treatment, without experiencing reductions in juvenile growth and adult mass.Animals acclimated under hot temperatures showed a significant lower preferred and voluntary maximum temperatures compared to animals acclimated under a cold temperature regime.We found no impact of acclimation treatment on behavioural thermal limits or standard metabolic rate.Overall, we show that alternating between access to preferred temperatures and having periods of energetic rest confer the greatest benefits for our animals. These results highlight the importance of natural body temperature variation for enhancing overall ectotherm performance and physiology, and the costs of novel thermal environments that fail to provide this variation. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

This paper uses a novel dataset on investments by the European Bank for Reconstruction and Development to quantify a (sizeable) trade‐off between the impact and financial objectives of a large lender. The unique feature of this dataset is ex ante records of impact. These are made at the early stages of work on each transaction alongside probability‐of‐default scores. Impact scores are further updated at the final approval stage with around 55 percent of transaction concepts translating into signed deals. We show that this approach delivers a simultaneous selection of debt investments on the quality of credit and impact with a sizable trade‐off between pursuing commercial and development objectives. For commercially riskier investments, impact characteristics have a greater bearing on the probability of an investment going ahead. We further use machine‐learning analysis to show that the impact of some investments is strengthened prior to project approval. [ABSTRACT FROM AUTHOR]

BACKGROUND: Facultative bacterial endosymbionts have the potential to influence the interactions between aphids, their natural enemies, and host plants. Among the facultative symbionts found in populations of the grain aphid Sitobion avenae in central Chile, the bacterium Regiella insecticola is the most prevalent. In this study, we aimed to investigate whether infected and cured aphid lineages exhibit differential responses to wheat cultivars containing varying levels of the benzoxazinoid DIMBOA (2,4‐dihydroxy‐7‐methoxy‐2H‐1,4‐benzoxazin‐3(4H)‐one), which is a xenobiotic compound produced by plants. Specifically, we examined the reproductive performance responses of the most frequently encountered genotypes of Sitobion avenae when reared on wheat seedlings expressing low, medium, and high concentrations of DIMBOA. RESULTS: Our findings reveal that the intrinsic rate of population increase (rm) in cured lineages of Sitobion avenae genotypes exhibits a biphasic pattern, characterized by the lowest rm and an extended time to first reproduction on wheat seedlings with medium levels of DIMBOA. In contrast, the aphid genotypes harbouring Regiella insecticola display idiosyncratic responses, with the two most prevalent genotypes demonstrating improved performance on seedlings featuring an intermediate content of DIMBOA compared to their cured counterparts. CONCLUSION: This study represents the first investigation into the mediating impact of facultative endosymbionts on aphid performance in plants exhibiting varying DIMBOA contents. These findings present exciting prospects for identifying novel targets for aphid control by manipulating the presence of aphid symbionts. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The study of functional traits and their relationship to trade-offs has provided valuable insights into how plants adapt to environmental changes. Nonetheless, further research is necessary to fully comprehend the subtropical montane trade-off patterns in moss functional traits and the impact of environmental gradients on the correlation of these traits. To address this gap, we conducted a study of 11 moss species (7 families, 9 genera) in 54 patches from two subtropical mountain ranges, examining 40 functional traits related to photosynthesis, nutrients, water retention, and architecture. Through principal component analysis (PCA) and bi-variate correlation analysis, our findings reveal a strong correlation between light capture and nutrient assimilation strategies, as evidenced by the coordination between the traits of light capture and nutrient per area along a main principal component. Interestingly, we observed a trend towards smaller leaves and leaf cells in species with higher capacity for photosynthesis and metabolism, consistent with global trait spectra in vascular plants. However, we found that the trade-off between light capture and nutrient assimilation strategies was independent of water-holding capacity at shoot levels. Instead, we found that water-holding capacity was closely associated with nutrient utilization, energy metabolism, chlorophyll synthesis, and the primary process of photosynthesis. Our results highlight the multiple dimensions of functional traits in subtropical montane mosses and demonstrate that variation in these traits is driven by water availability, slope, and canopy density. Overall, our study provides valuable insights into the co-variation of moss traits and how environmental changes may impact mosses and ecosystem function. [ABSTRACT FROM AUTHOR]

Student dropout prediction (SDP) in educational research has gained prominence for its role in analyzing student learning behaviors through time series models. Traditional methods often focus singularly on either prediction accuracy or earliness, leading to sub-optimal interventions for at-risk students. This issue underlines the necessity for methods that effectively manage the trade-off between accuracy and earliness. Recognizing the limitations of existing methods, this study introduces a novel approach leveraging multi-objective reinforcement learning (MORL) to optimize the trade-off between prediction accuracy and earliness in SDP tasks. By framing SDP as a partial sequence classification problem, we model it through a multiple-objective Markov decision process (MOMDP), incorporating a vectorized reward function that maintains the distinctiveness of each objective, thereby preventing information loss and enabling more nuanced optimization strategies. Furthermore, we introduce an advanced envelope Q-learning technique to foster a comprehensive exploration of the solution space, aiming to identify Pareto-optimal strategies that accommodate a broader spectrum of preferences. The efficacy of our model has been rigorously validated through comprehensive evaluations on real-world MOOC datasets. These evaluations have demonstrated our model's superiority, outperforming existing methods in achieving optimal trade-off between accuracy and earliness, thus marking a significant advancement in the field of SDP. [ABSTRACT FROM AUTHOR]

Objective: To achieve sustainable ecosystem management, it is necessary to understanding the complex relationships among multiple ecosystem services (ESs), especially in alpine ecosystems of the Northern Hemisphere where ESs have undergone significantly degradation. Therefore, a comprehensive exploration must be performed, from multiple time and spatial scales and perspectives, into the relationships and spatio-temporal changes of different ESs under climate warming. Method: We selected the Daxing’anling forest area, Inner Mongolia (DFAIM), which is both a sensitive, alpine ecosystem and an important ecological barrier in northern China, as the study area. We analyzed the local and overall relationships among four key ESs, soil conservation, water yield, carbon storage and habitat quality, using multiple methods at different time and spatial scales in 2013 and 2018. Further, we used the K-means clustering to identify ecosystem service bundles (ESBs) at different scales, and we proposed sustainable management strategies to optimize the ESs in this alpine ecosystems. Result: The main findings were as follows: (1) Most ES pairs had very significant synergistic relationships, but their synergistic strength did not increase from 2013 to 2018. The high-high synergies were mainly concentrated in the central DFAIM, while trade-offs and low-low synergies were concentrated in areas with more human interference. (2) Trade-offs dominated the relationships among all four ESs, which were widely distributed and significantly increased over time. The high synergies among all ESs were concentrated in the central and southern parts, but they decreased significantly over time. (3) The optimal number of ESBs in the DFAIM was five in both 2013 and 2018, at both the grid-scale and the forest management unit-scale. The distribution of ESBs was more fragmented at the grid-scale, but was relatively aggregated at the forestry management unit-scale. Changes in ESBs at the forestry management unit-scale became more pronounced over time. Conclusion: The local relationships between ES pairs were moderated and synergistic, but became more competitive over time. The overall relationships of the four ESs were dominated by trade-offs, with a significant increase in trade-off effects over time. Therefore, we suggested using our proposed ESBs to optimize ES management. These results can guide the implementation of sustainable integrated management strategies to optimize ESs supply levels in alpine ecosystems.

Resumo A discricionariedade dos agentes públicos vem ganhando importância como objeto de estudo por ser questão relevante na gestão e implementação de políticas públicas. Servidores públicos enfrentam decisões discricionárias de formas variadas, indo desde a construção de modos criativos para gerar bons impactos sociais até, no limite extremo, à inação, por medo de posterior responsabilização por conduta considerada indevida. Este estudo buscou compreender a experiência da discricionariedade para os servidores de carreiras de gestão e os dilemas existentes nessa atuação. Para tanto, procedeu-se a pesquisa qualitativa com especialistas em políticas públicas do estado de São Paulo e gestores governamentais do estado de Pernambuco. A pesquisa de campo englobou coleta por meio de 5 grupos focais. Na sequência, os dados foram analisados por meio da técnica da análise de conteúdo. Identificou-se que o principal dilema enfrentado pelos burocratas se encontra entre decidir dentro de sua competência e no melhor de seu conhecimento ou a inação, por medo de responsabilização, caso a decisão seja julgada como ilegal ou de má-fé. Por consequência, tem-se o chamado “apagão das canetas”. Há um constante trade-off entre a discricionariedade e a responsabilização, havendo meios pelos quais os servidores se valem para atenuar os riscos de sofrer sanções.

The trade-off and synergy relationship of ecosystem services is an important topic in the current assessment. The value of each service provided by the ecosystem is substantially affected by human activities, and conversely, its changes will also affect the relevant human decisions. Due to varying trade-offs among ecosystem services and synergies between them that can either increase or decrease, it is difficult to optimize multiple ecosystem services simultaneously, making it a huge challenge for ecosystem management. This study firstly develops a global Gross Ecosystem Product (GEP) accounting framework. It uses remote sensing data with a spatial resolution of 1 km to estimate the ecosystem services of forests, wetlands, grasslands, deserts, and farmlands in 179 major countries in 2018. The results show that the range of global GEP values is USD 112–197 trillion, with an average value of USD 155 trillion (the constant price), and the ratio of GEP to gross domestic product (GDP) is 1.85. The trade-offs and the synergies among different ecosystem services in each continent and income group have been further explored. We found a correspondence between the income levels and the synergy among ecosystem services within each nation. Among specific ecosystem services, there are strong synergies between oxygen release, climate regulation, and carbon sequestration services. A trade-off relationship has been observed between flood regulation and other services, such as water conservation and soil retention services in low-income countries. The results will help clarify the roles and the feedback mechanisms between different stakeholders and provide a scientific basis for optimizing ecosystem management and implementing ecological compensation schemes to enhance human well-being.

Abstract Life‐history theory predicts that investment in reproduction should decrease survival (the ‘cost of reproduction’). It is often assumed that energy allocation drives such trade‐offs, with limited energy available for both reproduction and survival. However, the underlying mechanisms remain poorly understood, maybe because survival costs of reproduction are only apparent when resources are limited. Here, we took advantage of a natural experiment created by fluctuating environmental conditions to compare energy expenditure of a seabird, the pelagic cormorant (Phalacrocorax pelagicus), between contrasting population‐scale scenarios of survival costs of reproduction. We used multi‐state capture–recapture modelling across 16 years to identify which breeding seasons induced high survival costs (survival ratebreeders

Operating leverage is one of the more popular parameters used in management practice and scientific research. However, in the literature, there are many definitions and methods of measurement, which are additionally presented imprecisely in both textbooks and scientific publications. This results in a great deal of freedom among authors in the selection of measures for estimating operating leverage and the interpretation of the results, which has a negative impact on functionality for synthesis and theory building. Although some authors made such reservations clear as early as the 1980s, the situation has not changed. Using a three-step process of asking questions relating to how it looks, how it works, and how it compares to other “somethings”, the article conducts a critical analysis of the operational leverage measures used in recent publications and proposes to organize and refine the concept of operational leverage as leverage to increase value added and profit at a given output level using a trade-off mechanism between variable and fixed costs. Finally, the article suggests directions for future research and provides tips on how to incorporate the proposed concept of operating leverage into empirical research.

Under controlled laboratory conditions, previous studies have shown that selection can produce repeatable evolutionary trajectories. Yet, the question remains for many of these studies if, given identical starting populations, evolution in the wild proceeds in a non-random direction. In the present study, we investigated the extent to which rapid evolution in the wild is parallel by monitoring the genetic composition of replicate populations of Daphnia in field mesocosms containing two clonal genotypes. We found parallel changes across all nine mesocosms, in which the same genotype increased in frequency. To probe whether genotype-specific response to resource abundance could have led to this frequency change, we conducted a life-history assay under high-resource abundance and low-resource abundance. We found that resource exploitation differed by genotype, in that, while one genotype (the winner in the field mesocosms) was more fit than the other genotype at high resources, the other genotype performed slightly better at low resources. We suspect that levels of resource abundance found in the summer field mesocosms had values in which the genotype better with abundant resources had the advantage. These findings suggest that variation in certain traits associated with resource acquisition can drive genotype frequency change.

Numerous studies have shown that under a limited water supply, a larger root biomass is associated with an increased above-ground biomass. Root biomass, while genetically controlled, is also greatly affected by the environment with varying plasticity levels. In this context, understanding the relationship between the biomass of shoots and roots appears prudent. In this study, we analyze this relationship in a large dataset collected from multiple experiments conducted up to different growth stages in bread wheat (Triticum aestivum L.) and its wild relatives. Four bread wheat mapping populations as well as wild and domesticated members of the Triticeae tribe were evaluated for the root and shoot biomass allocation patterns. In the analyzed dataset the root and shoot biomasses were directly related to each other, and to the heading date, and the correlation values increased in proportion to the length of an experiment. On average, 84.1% of the observed variation was explained by a positive correlation between shoot and root biomass. Scatter plots generated from 6353 data points from numerous experiments with different wheats suggest that at some point, further increases in root biomass negatively impact the shoot biomass. Based on these results, a preliminary study with different water availability scenarios and growth conditions was designed with two cultivars, Pavon 76 and Yecora Rojo. The duration of drought and water level significantly affected the root/shoot biomass allocation patterns. However, the responses of the two cultivars were quite different, suggesting that the point of diminishing returns in increasing root biomass may be different for different wheats, reinforcing the need to breed wheats for specific environmental challenges.

Evolutionary medicine - i.e. the application of insights from evolution and ecology to biomedicine - has tremendous untapped potential to spark transformational innovation in biomedical research, clinical care and public health. Fundamentally, a systematic mapping across the full diversity of life is required to identify animal model systems for disease vulnerability, resistance, and counter-resistance that could lead to novel clinical treatments. Evolutionary dynamics should guide novel therapeutic approaches that target the development of treatment resistance in cancers (e.g., via adaptive or extinction therapy) and antimicrobial resistance (e.g., via innovations in chemistry, antimicrobial usage, and phage therapy). With respect to public health, the insight that many modern human pathologies (e.g., obesity) result from mismatches between the ecologies in which we evolved and our modern environments has important implications for disease prevention. Life-history evolution can also shed important light on patterns of disease burden, for example in reproductive health. Experience during the COVID-19 (SARS-CoV-2) pandemic has underlined the critical role of evolutionary dynamics (e.g., with respect to virulence and transmissibility) in predicting and managing this and future pandemics, and in using evolutionary principles to understand and address aspects of human behavior that impede biomedical innovation and public health (e.g., unhealthy behaviors and vaccine hesitancy). In conclusion, greater interdisciplinary collaboration is vital to systematically leverage the insight-generating power of evolutionary medicine to better understand, prevent, and treat existing and emerging threats to human, animal, and planetary health.

The synergistic effect between heterogeneous structures has been proved to enhance the strength and plasticity of alloys, especially in the context of single-phase face-centered cubic (FCC) high-entropy alloys with low stacking fault energy. This study explores the synergistic effects of heterogeneous structures on the strength and plasticity of single-phase FCC FeCoCrNiMo0.2 high-entropy alloys. Through a combination of cryogenic rolling and annealing at 1000 °C for 0.5 h (RA-1000), the alloy demonstrates exceptional strength-ductility synergy and work-hardening ability. The heterogeneous structure comprises fine grains, nano-scale rich- (Cr, Mo) σ phase, and high-density annealing twins. The interaction of σ precipitation and FCC matrix induces heterogeneous deformation-induced strengthening (HDI), while annealing twins and stacking faults act as barriers to dislocation movement, enhancing strength and ductility through a dynamic Hall-Petch effect. Additionally, chemically ordered structures, ordered L12 phase, and type 63 topologically close-packed phases in RA-1000 alloys contribute to improved strain hardening via anti-phase boundaries. This work provides valuable insights for designing multi-scale heterogeneous structures to strengthen high-entropy alloys.

An experiment was conducted to examine how dietary interventions reducing enteric methane (CH4) emissions influence manure CH4 emissions in biogas production (as biochemical methane potential (BMP)) or under static conditions mimicking natural manure storage conditions. Experimental treatments consisted of a factorial arrangement of high (HF: 0.65) or low (LF: 0.35) levels of forage and 0 or 50 g of rapeseed oil per kg of diet dry matter. Oil supplementation reduced daily enteric CH4 emissions, especially in the HF diet, by 20%. Greater dietary concentrate proportion reduced CH4 yield and intensity (6 and 12%, respectively) and decreased pH, increased total volatile fatty acids, and molar proportions of butyrate and valerate in feces incubated under static conditions. Oil supplementation increased daily BMP and BMP calculated per unit of organic matter (OM) (17 and 15%, respectively). Increased dietary concentrate had no impact on daily BMP and BMP per unit of OM, whereas it reduced daily CH4 production by 89% and CH4 per unit of OM by 91% under static conditions. Dietary oil supplementation tended to decrease fecal CH4 production per unit of digestible OM (23%) under static conditions. Diets had no impact on the alpha diversity of ruminal prokaryotes. After incubation, the fecal prokaryote community was significantly less diverse. Diets had no effect on alpha diversity in the BMP experiment, but static trial fecal samples originating from the HF diet showed significantly lower diversity compared with the LF diet. Overall, the tested dietary interventions reduced enteric CH4 emissions and reduced or tended to reduce manure CH4 emissions under static conditions, indicating a lack of trade-off between enteric and manure CH4 emissions. The potential for increasing CH4 yields in biogas industries due to dietary interventions could lead to a sustainable synergy between farms and industry.

Abstract Background In the evolution from unicellular to multicellular life forms, natural selection favored reduced cell proliferation and even programmed cell death if this increased organismal fitness. Could reduced individual fertility or even programmed organismal death similarly increase the fitness of colonies of closely-related metazoan organisms? This possibility is at least consistent with evolutionary theory, and has been supported by computer modelling. Caenorhabditis elegans has a boom and bust life history, where populations of nematodes that are sometimes near clonal subsist on and consume food patches, and then generate dauer larva dispersal propagules. A recent study of an in silico model of C. elegans predicted that one determinant of colony fitness (measured as dauer yield) is minimization of futile food consumption (i.e. that which does not contribute to dauer yield). One way to achieve this is to optimize colony population structure by adjustment of individual fertility. Results Here we describe development of a C. elegans colony fitness assay, and its use to investigate the effect of altering population structure on colony fitness after population bust. Fitness metrics measured were speed of dauer production, and dauer yield, an indirect measure of efficiency of resource utilization (i.e. conversion of food into dauers). We find that with increasing founder number, speed of dauer production increases (due to earlier bust) but dauer yield rises and falls. In addition, some dauer recovery was detected soon after the post-colony bust peak of dauer yield, suggesting possible bet hedging among dauers. Conclusions These results suggest the presence of a fitness trade-off at colony level between speed and efficiency of resource utilization in C. elegans. They also provide indirect evidence that population structure is a determinant of colony level fitness, potentially by affecting level of futile food consumption.

AbstractThe paper investigates aggregation bias by comparing the risk and returns characteristics of stock exchange-traded shares and Treasury bills (T’bills) in Ghana. The study uses end of period annualized data on T’bills and stocks returns, and inflation from 1990 to 2020. We mainly consider four separate investment periods: 1990–2000, 2001–2010, 2011–2020, and 1990–2020 (i.e. the aggregated period) in order to determine possible aggregation bias occurring from lumping the years together. We measure average annual returns, standard deviations, co-efficient of variations, Sharpe ratio, ANOVA, Jarque-Bera test, maximum drawdowns (MDD), and correlation analysis to determine risk and return characteristics of the two instruments. The study finds that T'bills compared to stocks shows higher returns yet lower risk, thereby indicating an inverted yield curve. Levene’s Test for Equality of Variances indicates stocks significantly outperformed T’bills over the 31-year aggregated period. The study reveals the presence of aggregation bias as stock and T’bill risk and return characteristics of two segregated periods (i.e. 1990–2000 and 2011–2020) contradict the general expectation of risk-return trade-off theory contrary to that of the aggregated period. The MDD, ANOVA results, Anova F-test and Welch F-test reveal aggregation bias for T’bills but not for stocks. We recommend future studies to ensure that analysis and conclusions made do not suffer aggregation bias by disaggregating aggregated units.

Defence theories provide predictions about trade‐offs in the allocation of resources to defence and growth. However, very little is known about how pressure from herbivores influences the allocation of resources during reproduction.Two common peatland bryophyte species, Sphagnum angustifolium and S. capillifolium, were chosen as study species. Vegetative and reproductive shoots of both Sphagnum species were subjected to treatments with and without herbivores in a lab experiment. After 4 weeks of exposure to herbivores in a growth chamber, we measured biomass production, net photosynthesis rate, defence traits (phenolics in leachate and phenolics in extract), nonstructural carbohydrates (soluble sugar and starch), and reproductive traits (capsule number, weight and diameter, and spore germination) of both Sphagnum species.Reproductive shoots had higher constitutive defence than vegetative shoots in S. angustifolium, and a similar pattern was observed in S. capillifolium. With herbivory, reproductive shoots showed stronger induced defence (released more phenolics) than vegetative shoots in S. capillifolium, but not in S. angustifolium. Herbivory had no effect on capsule number, weight, or diameter, but reduced spore germination percentage by more than half in both species.Our study highlights the hidden effects of herbivory on reproduction of Sphagnum and indicates the presence of maternal effects in bryophytes. Ecologists will benefit from examining both quality‐ and quantity‐based traits when attempting to estimate the herbivory effect on plant fitness. [ABSTRACT FROM AUTHOR]

Simple Summary: On a global scale, about 20% of bird species nest in tree cavities, and many of these species will utilise artificial nestboxes. Homeowners often add nestboxes to gardens to provide new opportunities for enjoyment and engagement with nature. Nestbox schemes can also be used for conservation, especially in environments that have few natural cavities, such as open landscapes and woodlands with relatively young and even-aged trees, including plantations. However, tree-nesting birds using simple wooden nestboxes can be at risk from predators. A range of different strategies to reduce predation risk has been developed. These typically involve: (1) modifying the nestbox itself by, for example, adding a metal plate around the entrance hole to stop predators enlarging the hole or changing construction materials; (2) modifying the immediate surroundings of the nestbox, for example, by using barriers to prevent predator access; or (3) modifying nestbox placement. A common assumption is that such interventions provide a net benefit. However, this is not necessarily true as predator-proofing avian nestboxes often has hidden costs, such as changing nest temperature or humidity or making it harder for adult birds to feed their chicks. This review considers intervention effectiveness and the potential for hidden costs to make recommendations for practice. Nestboxes are commonly used to increase the number and quality of nest sites available to birds that usually use tree cavities and are considered an important conservation intervention. Although usually safer than natural cavities, birds nesting in simple, unmodified wooden nestboxes remain at risk of depredation. Accordingly, numerous design and placement modifications have been developed to 'predator-proof' nestboxes. These include: (1) adding metal plates around entrance holes to prevent enlargement; (2) affixing wire mesh to side panels; (3) deepening boxes to increase distance to nest cup; (4) creating external entrance 'tunnels' or internal wooden ledges; (5) using more robust construction materials; (6) developing photosensitive shutters to exclude nocturnal predators; (7) using baffles to block climbing mammals; and (8) regular replacement and relocation. However, the benefits and costs of these modifications are not always well understood. In this global review, we collate information on predator-proofing avian nestboxes designed for tree cavity-nesting birds to assess the efficacy of techniques for different predators (mammalian, avian, and reptilian) in different contexts. We critique the potential for modifications to have unintended consequences—including increasing nest building effort, altering microclimate, reducing provisioning rate, and elevating ectoparasite and microbial loads—to identify hidden costs. We conclude by highlighting remaining gaps in knowledge and providing guidance on optimal modifications in different contexts. [ABSTRACT FROM AUTHOR]

Summary: Adaptations of plants to phosphorus (P) deficiency include reduced investment of leaf P in storage (orthophosphates in vacuoles), nucleic acids and membrane lipids. Yet, it is unclear how these adaptations are associated with plant ecological strategies.Five leaf P fractions (orthophosphate P, Pi; metabolite P, PM; nucleic acid P, PN; lipid P, PL; and residual P, PR) were analysed alongside leaf economic traits among 35 Australian woody species from three habitats: one a high‐P basalt‐derived soil and two low‐P sandstone‐derived soils, one undisturbed and one disturbed by human activities with artificial P inputs.Species at the undisturbed low‐P site generally exhibited lower concentrations of total leaf P ([Ptotal]), primarily associated with lower concentrations of Pi, and PN. The relative allocation of P to each fraction varied little among sites, except that higher PL per [Ptotal] (rPL) was recorded at the undisturbed low‐P site than at the high‐P site. This higher rPL, reflecting relative allocation to membranes, was primarily associated with lower concentrations of leaf nitrogen at the undisturbed low‐P site than at the high‐P site.Associations between leaf P fractions and leaf nitrogen may provide a basis for understanding the variation in plant ecological strategies dependent on soil P availability. [ABSTRACT FROM AUTHOR]

We explore the observed plasticity in Tuta absoluta age and size at pupation in response to water and nutrients scarcity. Using a minimal theoretical model, we demonstrate that the observed plasticity can be viewed as a strategic adaptation of individuals aimed at maximizing their reproductive output under stressful environmental conditions. T. absoluta plasticity is then found to align with expectations from fundamental principles of life history theory. [ABSTRACT FROM AUTHOR]

How traits at multiple levels of biological organization evolve in a correlated fashion in response to directional selection is poorly understood, but two popular models are the very general "behavior evolves first" (BEF) hypothesis and the more specific "morphology-performance-behavior-fitness" (MPBF) paradigm. Both acknowledge that selection often acts relatively directly on behavior and that when behavior evolves, other traits will as well but most with some lag. However, this proposition is exceedingly difficult to test in nature. Therefore, we studied correlated responses in the high-runner (HR) mouse selection experiment, in which four replicate lines have been bred for voluntary wheel-running behavior and compared with four nonselected control (C) lines. We analyzed a wide range of traits measured at generations 20–24 (with a focus on new data from generation 22), coinciding with the point at which all HR lines were reaching selection limits (plateaus). Significance levels (226 P values) were compared across trait types by ANOVA, and we used the positive false discovery rate to control for multiple comparisons. This meta-analysis showed that, surprisingly, the measures of performance (including maximal oxygen consumption during forced exercise) showed no evidence of having diverged between the HR and C lines, nor did any of the life history traits (e.g., litter size), whereas body mass had responded (decreased) at least as strongly as wheel running. Overall, results suggest that the HR lines of mice had evolved primarily by changes in motivation rather than performance ability at the time they were reaching selection limits. In addition, neither the BEF model nor the MPBF model of hierarchical evolution provides a particularly good fit to the HR mouse selection experiment. [ABSTRACT FROM AUTHOR]

Simple Summary: The idea that invertebrates feel pain is often dismissed because of claims that their responses to noxious stimuli are simply reflexes. Reflexes do not require higher-order processing, but that is required for pain experience. One way to test this claim is to ask if animals only respond to the noxious stimulus or if that response can be influenced by other motivations. Here, we report that shore crabs that enter a dark shelter from a light area and receive a shock are subsequently less likely to use that shelter if the light level is low and the shock level high. They trade their requirement to avoid bright light for the avoidance of the noxious shock. They learn to avoid the shelter and show signs of anxiety when deciding to enter the shelter to escape the light. These observations demonstrate that the responses to shock are not reflexes but are decisions that should improve the outcome better than a reflex alone. This balancing of needs is a key expectation of pain, and the results are consistent with the idea that crabs feel pain. The suggestion that decapod crustaceans might experience pain has been dismissed by some authors who claim decapods only respond to noxious stimuli by nociceptive reflexes. Because reflexes do not require complex neuronal processing, but pain does, demonstrating reflex responses to noxious stimuli would not support the case for pain. Here, we report an experiment in which shore crabs are repeatedly placed in a light area (20 trials), but the animals can avoid the light by moving to a dark shelter. However, some crabs received an electric shock of 6 or 12 volts each time they entered the shelter. Those receiving either level of shock swiftly reduced their use of shelters and remained in the light. However, the magnitude of shelter avoidance was influenced by the brightness of the arena and the intensity of the shock. Shelter use was subsequently reduced to a greater extent if the shock level was high and the light intensity low. That is, crabs traded their avoidance of shock for their avoidance of bright light. Further, these animals showed avoidance learning and demonstrated activities suggesting anxiety, such as contact with the tank wall in the light area and increased latency to enter shelters when making the decision to enter the shelter if they had received shock in earlier trials. These results fulfil three key behavioural criteria for pain and, thus, are consistent with the idea that decapods can experience pain. [ABSTRACT FROM AUTHOR]