Role of climatic variability in shaping intraspecific variation of thermal tolerance in Mediterranean water beetles.

The climatic variability hypothesis (CVH) predicts that organisms in more thermally variable environments have wider thermal breadths and higher thermal plasticity than those from more stable environments. However, due to evolutionary trade-offs, taxa with greater absolute thermal limits may have little plasticity of such limits (trade-off hypothesis). The CVH assumes that climatic variability is the ultimate driver of thermal tolerance variation across latitudinal and altitudinal gradients, but average temperature also varies along such gradients. We explored intraspecific variation of thermal tolerance in three typical Mediterranean saline water beetles (families Hydrophilidae and Dytiscidae). For each species, we compared two populations where the species coexist, with similar annual mean temperature but contrasting thermal variability (continental vs. coastal population). We estimated thermal limits of adults from each population, previously acclimated at 17, 20, or 25 °C. We found species-specific patterns but overall, our results agree with the CVH regarding thermal ranges, which were wider in the continental (more variable) population. In the two hydrophilid species, this came at the cost of losing plasticity of the upper thermal limit in this population, supporting the trade-off hypothesis, but not in the dytiscid one. Our results support the role of local adaptation to thermal variability and trade-offs between basal tolerance and physiological plasticity in shaping thermal tolerance in aquatic ectotherms, but also suggest that intraspecific variation of thermal tolerance does not fit a general pattern among aquatic insects. Overlooking such intraspecific variation could lead to inaccurate predictions of the vulnerability of aquatic insects to global warming.

Perfectionistic Environments and Irrational Beliefs on the Transition to Elite Athletic Performance: A Longitudinal Study.

This study aimed to longitudinally evaluate talented athletes' levels of perfectionism, irrational beliefs, and motivations with regard to their athletic careers. A total of 390 athletes from U14, U16, and junior categories (MageT1 = 15.42) answered shortened versions of the Sport-MPS2, iPBI, and BRSQ during two consecutive seasons, along with questions referring to their current and predicted prioritization of sports and education. Participants reported high levels of perfectionistic strivings and medium to low levels of socially prescribed perfectionism and concern over mistakes decreasing from T1 to T2. A decrease was also found for demandingness and awfulizing, but increased levels were found for depreciation in T2. Participants report very high intrinsic motivation with low levels of external regulation and amotivation, but intrinsic motivation decreased from season to season. This general profile varied depending upon future expectancies toward dedication to sports and education. Those who foresaw a prioritized dedication to sports presented significantly higher levels of socially prescribed perfectionism, perfectionistic strivings, and intrinsic motivation, while those who considered that sports would not be prioritized in the following 5 years reported higher levels of demandingness, awfulizing, depreciation, and amotivation. Additionally, while current levels of motivation (T2) seemed to be predicted mainly by previous motivation levels (T1), significant predictive capacity was also detected for socially prescribed perfectionism positively predicting external regulations and amotivation, perfectionistic strivings negatively predicting amotivation, and depreciation negatively predicting intrinsic motivation and positively predicting both extrinsic regulation and amotivation. We discuss the potential perils of developing extremely demanding environments, as they could potentially result in poor motivational profiles of athletes in their talent development stage during the junior to senior transition.

Towards evidence-based conservation of subterranean ecosystems.

Subterranean ecosystems are among the most widespread environments on Earth, yet we still have poor knowledge of their biodiversity. To raise awareness of subterranean ecosystems, the essential services they provide, and their unique conservation challenges, 2021 and 2022 were designated International Years of Caves and Karst. As these ecosystems have traditionally been overlooked in global conservation agendas and multilateral agreements, a quantitative assessment of solution-based approaches to safeguard subterranean biota and associated habitats is timely. This assessment allows researchers and practitioners to understand the progress made and research needs in subterranean ecology and management. We conducted a systematic review of peer-reviewed and grey literature focused on subterranean ecosystems globally (terrestrial, freshwater, and saltwater systems), to quantify the available evidence-base for the effectiveness of conservation interventions. We selected 708 publications from the years 1964 to 2021 that discussed, recommended, or implemented 1,954 conservation interventions in subterranean ecosystems. We noted a steep increase in the number of studies from the 2000s while, surprisingly, the proportion of studies quantifying the impact of conservation interventions has steadily and significantly decreased in recent years. The effectiveness of 31% of conservation interventions has been tested statistically. We further highlight that 64% of the reported research occurred in the Palearctic and Nearctic biogeographic regions. Assessments of the effectiveness of conservation interventions were heavily biased towards indirect measures (monitoring and risk assessment), a limited sample of organisms (mostly arthropods and bats), and more accessible systems (terrestrial caves). Our results indicate that most conservation science in the field of subterranean biology does not apply a rigorous quantitative approach, resulting in sparse evidence for the effectiveness of interventions. This raises the important question of how to make conservation efforts more feasible to implement, cost-effective, and long-lasting. Although there is no single remedy, we propose a suite of potential solutions to focus our efforts better towards increasing statistical testing and stress the importance of standardising study reporting to facilitate meta-analytical exercises. We also provide a database summarising the available literature, which will help to build quantitative knowledge about interventions likely to yield the greatest impacts depending upon the subterranean species and habitats of interest. We view this as a starting point to shift away from the widespread tendency of recommending conservation interventions based on anecdotal and expert-based information rather than scientific evidence, without quantitatively testing their effectiveness.

Climatic stability, not average habitat temperature, determines thermal tolerance of subterranean beetles.

The climatic variability hypothesis predicts the evolution of species with wide thermal tolerance ranges in environments with variable temperatures, and the evolution of thermal specialists in thermally stable environments. In caves, the extent of spatial and temporal thermal variability experienced by taxa decreases with their degree of specialization to deep subterranean habitats. We use phylogenetic generalized least squares to model the relationship among thermal tolerance (upper lethal limits), subterranean specialization (estimated using ecomorphological traits), and habitat temperature in 16 beetle species of the tribe Leptodirini (Leiodidae). We found a significant, negative relationship between thermal tolerance and the degree of subterranean specialization. Conversely, habitat temperature had only a marginal effect on lethal limits. In agreement with the climatic variability hypothesis and under a climate change context, we show that the specialization process to live in deep subterranean habitats involves a reduction of upper lethal limits, but not an adjustment to habitat temperature. Thermal variability seems to exert a higher evolutionary pressure than mean habitat temperature to configure the thermal niche of subterranean species. Our results provide novel insights on thermal physiology of species with poor dispersal capabilities and on the evolutionary process of adaptation to subterranean environments. We further emphasize that the pathways determining vulnerability of subterranean species to climate change greatly depend on the degree of specialization to deep subterranean environments.

Plasticity of thermal performance curves in a narrow range endemic water beetle.

Thermal history can plastically alter the response of ectotherms to temperature, and thermal performance curves (TPCs) are powerful tools for exploring how organismal-level performance varies with temperature. Plasticity in TPCs may be favoured in thermally variable habitats, where it can result in fitness benefits. However, thermal physiology remains insufficiently studied for freshwater insects despite freshwater biodiversity being at great risk under global change. Here, we assess how acclimation at either summer or winter average temperatures changes TPCs for locomotion activity and metabolism in Enochrus jesusarribasi (Hydrophilidae), a water beetle endemic to shallow saline streams in SE Spain. This beetle is a bimodal gas exchanger and so we also assessed how aerial and aquatic gas exchange varied across temperatures for both acclimation treatments. Responses of locomotory TPCs to thermal acclimation were relatively weak, but high temperature acclimated beetles tended to exhibit higher maximum locomotor activity and reduced TPC breadth than those acclimated at lower temperature. High temperature acclimation increased the thermal sensitivity of metabolic rates, contrary to the response generally found in aquatic organisms. Higher metabolic rates upon high temperature acclimation were achieved by increasing aerial, rather than aquatic oxygen uptake. Such plastic respiratory behaviour likely contributed to enhanced locomotor performance at temperatures around the optimum and thermal plasticity could thus be an important component in the response of aquatic insects to climate change. However, high temperature acclimation appeared to be detrimental for locomotion in subsequent exposure at upper sublethal temperatures, suggesting that this narrow range endemic may be vulnerable to future climate warming. This study demonstrates that TPCs are context-specific, differing with performance metric as well as thermal history. Such context dependency must be considered when using TPCs to predict organismal responses to climate change.

Distribution Levels of Particulate Matter Fractions (<2.5 µm, 2.5-10 µm and >10 µm) at Seven Primary Schools in a European Ceramic Cluster.

This study addresses the concentration of particulate matter and their size using a statistical analysis of data obtained inside seven schools located in the towns of Castellón (S1, S2, and S3), Alcora (S4, S5, and S6) and Lucena (S7) in northeast Spain. Samples were taken for five to eight hours, depending on school hours, to obtain a monthly sample for each school. The main goal of this study is to assess the differences depending on the type of location and the sampling point to be able to design corrective measures that improve the habitability and safety of the teaching spaces analyzed. The lowest concentrations of fine particulate matter, less than 2.5 µm, were registered at the rural location. The values of these particles found in industrial and urban locations were not substantially different. In the case of particulate matter between 2.5 and 10 µm, significant differences were observed between the three types of locations. The lowest concentrations of particles larger than 10 µm were registered at the rural location, and the highest concentrations were found at the industrial locations. Among the urban stations, the particle concentration of this fraction in station S2 was significantly higher than that in stations S1 and S3, which had similar concentrations. These values are also similar to those registered at school S6, which is at an industrial location. The resuspension of particles from both indoor sources as well as those transported from the outside is an important factor in the concentrations of particles inside classrooms.

Cuticle Hydrocarbons Show Plastic Variation under Desiccation in Saline Aquatic Beetles.

In the context of aridification in Mediterranean regions, desiccation resistance and physiological plasticity will be key traits for the persistence of aquatic insects exposed to increasing desiccation stress. Control of cuticular transpiration through changes in the quantity and composition of epicuticular hydrocarbons (CHCs) is one of the main mechanisms of desiccation resistance in insects, but it remains largely unexplored in aquatic ones. We studied acclimation responses to desiccation in adults of two endemic water beetles from distant lineages living in Mediterranean intermittent saline streams: Enochrus jesusarribasi (Hydrophilidae) and Nebrioporus baeticus (Dytiscidae). Cuticular water loss and CHC composition were measured in specimens exposed to a prior non-lethal desiccation stress, allowed to recover and exposed to a subsequent desiccation treatment. E. jesusarribasi showed a beneficial acclimation response to desiccation: pre-desiccated individuals reduced cuticular water loss rate in a subsequent exposure by increasing the relative abundance of cuticular methyl-branched compounds, longer chain alkanes and branched alkanes. In contrast, N. baeticus lacked acclimation capacity for controlling water loss and therefore may have a lower physiological capacity to cope with increasing aridity. These results are relevant to understanding biochemical adaptations to drought stress in inland waters in an evolutionary and ecological context.

Motivaciones hacia la actividad física de adolescentes, adultos mayores y exdeportistas de élite: Un análisis cualitativo / Motivations toward Physical Activity of Adolescents, Older Adults and Former Elite Athletes: A Qualitative Analysis / Motivações para a atividade física em adolescentes, idosos e ex-atletas de elite: Uma análise qualitativa

Resumen Objetivo. Explorar las similitudes y diferencias de los tipos de motivación hacia la práctica de actividad física (AF) de adolescentes, adultos mayores y exdeportistas de élite, desde la Teoría de la Autodeterminación, para la creación de programas de AF. Método. La recolección de los datos se llevó a cabo mediante grupos focales: tres con adolescentes, dos con adultos mayores y uno con exdeportistas. En total, participaron 17 adolescentes, 14 adultos mayores y cuatro exdeportistas. Se realizó un análisis temático. Resultados. Para cada grupo se encontró un conjunto de factores de motivación autónoma, controlada y amotivacionales hacia la práctica de AF. En común, en los tres grupos estudiados, se identificaron la diversión, la socialización y la salud como factores de motivación hacia la práctica de AF. Conclusión. Las orientaciones para la creación de programas de AF para adolescentes se centraron en la individualización de sus objetivos y la percepción en la libertad de elección relacionada con cada AF. En adultos mayores, el enfoque fue hacia nuevas experiencias, considerando de forma significativa el perfil del monitor. Para el grupo de exdeportistas se propone que el punto de partida sea la reconceptualización de la práctica de AF después de la carrera deportiva.

Abstract Objective. To explore the similarities and differences between the types of motivation towards the practice of physical activity (PA) in different populations (adolescents, older adults and former elite athletes) for the creation of PA programs that reflect the particularities of those populations. Method. The qualitative data collection was carried out through focus groups; three groups with adolescents, two with older adults and one with former elite athletes. In total, 17 adolescents, 14 older adults and four former elite athletes participated in this study. A thematic analysis was conducted. Results. The results are shown based on autonomous, controlled motivation and amotivation towards the practice of physical activity for each group. Fun, socialization and health have been identified as motivating factors towards the PA practice common in the three groups studied. Conclusion. Orientations are proposed for the creation of PA programs. For adolescents, the proposal would include the individualization of their objectives and the perception of the freedom of choice in relation to the PA. For the group of older adults, it is important to offer new experiences, taking into account the profile of the monitor. For the group of former elite athletes, the proposed starting point would be the reconceptualization of the PA practice after the athletic career.

Resumo Escopo. Explorar as similitudes e as diferencias dos tipos de motivação para a prática física (AF) de adolescentes, idosos, e ex-atletas de elite, desde a Teoria da Autodeterminação, para a criação de programas de AF. Metodologia. A recolecção de dados foi feita em grupos focais: três com adolescentes, dois com idosos e um com ex-atletas. Foi realizada uma análise temática. Resultados. Para cada grupo foi encontrado um conjunto de fatores de motivação autónoma, controlada e amotivacionais para a prática de AF. Em comum, nos três grupos estudados, foram identificadas a diversão, a socialização e a saúde como fatores de motivação para a prática de AF. Conclusão. As orientações para a criação de programas de AF para adolescentes estiveram centradas na individualização dos seus escopos e a percepção na liberdade de eleição relacionada com cada AF. Nos idosos, o enfoque foi para as novas experiências, considerando de forma significativa o perfil do monitor. Para o grupo de ex-atletas se propõe que o ponto de partida seja a reconceptualização da prática de AF depois da carreira esportiva.

Can Multi-Item Measures and Single-Item Measures be Trusted to Assess Self-Determination Theory Constructs in the Elderly? / ¿Son fiables las Medidas Multi-Ítem y las Mono-Ítem Para Evaluar los Constructos de la Teoría de la Auto-Determinación en Personas Mayores?

BACKGROUND: Measuring complex constructs, such as those from self-determination theory models, is challenging in the elderly due to the response process, particularly in collective data gathering. In order to examine this construct in physical activity settings we aimed at determining whether single-item measures were as good as pre-existing multi-item measures. For that reason, we developed seven single-item measures targeting perceived interpersonal styles, basic needs satisfaction, and well-being. METHOD: We gathered evidence of validity and reliability for multi-item measures and single-item measures based on a sample of 128 elderly adults. Another sample of 62 elderly adults provided test-retest reliability for the single-item measures. RESULTS: Favourable evidence of the expected internal structure, concurrent validity, and reliability was obtained for competence- and relatedness-supportive styles, and for satisfaction of the basic psychological need of relatedness, fairly good evidence was obtained for subjective vitality, whereas mixed evidence was obtained for autonomy-supportive style and the satisfaction of the basic psychological needs of autonomy and competence. CONCLUSIONS: Single-item measures proved to be psychometrically sound substitutes for their multi-item counterparts, but the autonomy constructs need to be reconsidered. Furthermore the response process and consequences of testing should play a prominent role when devising questionnaires for the elderly

ANTECEDENTES: medir constructos complejos como los de la Teoría de la auto-determinación es un reto en personas mayores debido al proceso de respuesta. Para examinar estos constructos en actividad física nuestro objetivo fue comparar si las medidas mono-ítem eran igual de óptimas que las medidas multi-ítem pre-existentes. Por ello, desarrollamos siete medidas mono-ítem relacionadas con el estilo interpersonal, la satisfacción de las necesidades básicas y la vitalidad. MÉTODO: obtuvimos evidencias de validez y fiabilidad para las medidas multi-ítem y las medidas mono-ítem en una muestra de 128 personas mayores. Con otra muestra de 62 personas examinamos la fiabilidad test-retest para las medidas mono-ítem. RESULTADOS: se obtuvo evidencia favorable relativa a la estructura interna, validez concurrente y fiabilidad para apoyo a la competencia y a la relación, y para satisfacción de la relación y vitalidad, mientras que para apoyo a la autonomía, satisfacción de la autonomía y de la competencia fue no conclusiva. CONCLUSIONES: las medidas mono-ítem se han comportado como buenos sustitutos psicométricos para sus medidas multi-ítem homólogas, pero es necesario reconsiderar los constructos de autonomía, y además el proceso de respuesta y las consecuencias de la evaluación deben desempeñar un papel preeminente cuando se crean cuestionarios para personas mayores

Can Multi-Item Measures and Single-Item Measures be Trusted to Assess Self-Determination Theory Constructs in the Elderly?

BACKGROUND: Measuring complex constructs, such as those from self-determination theory models, is challenging in the elderly due to the response process, particularly in collective data gathering. In order to examine this construct in physical activity settings we aimed at determining whether single-item measures were as good as pre-existing multi-item measures. For that reason, we developed seven single-item measures targeting perceived interpersonal styles, basic needs satisfaction, and well-being. METHOD: We gathered evidence of validity and reliability for multi-item measures and single-item measures based on a sample of 128 elderly adults. Another sample of 62 elderly adults provided test-retest reliability for the single-item measures. RESULTS: Favourable evidence of the expected internal structure, concurrent validity, and reliability was obtained for competence- and relatedness-supportive styles, and for satisfaction of the basic psychological need of relatedness, fairly good evidence was obtained for subjective vitality, whereas mixed evidence was obtained for autonomy-supportive style and the satisfaction of the basic psychological needs of autonomy and competence. CONCLUSIONS: Single-item measures proved to be psychometrically sound substitutes for their multi-item counterparts, but the autonomy constructs need to be reconsidered. Furthermore the response process and consequences of testing should play a prominent role when devising questionnaires for the elderly.

Morphological Characterization of Indoor Airborne Particles in Seven Primary Schools.

This paper focuses on a study of fine (less than 2.5 µm) airborne particles collected inside seven primary schools located on a coastal Mediterranean area which has a significant industrial hub for the processing of clays and other minerals as raw materials. Of the seven schools, three are located in an urban area 20 km away from the main industrial hub, three are in a town located next to the industrial estate, and one is in a rural location, 30 km from the industrial area. The objective of this study is to identify the main types of particles found in the three examined environments. The particle matter identified in the fine particle samples is grouped into three main groups: mineral compounds, particles from combustion processes and phases emitted in high-temperature industrial processes. The mineral particles, which can come from natural or anthropogenic emissions, have been classified depending on their morphology as isometric allotriomorphs or subidiomorphs, with a tabular habit; acicular forms; or pure crystalline forms. Compounds from combustion processes have two types of morphologies: spheroid and dendritic soot particles. Additionally, in smaller quantities, spherical particles associated with high-temperature industrial processes, such as the emissions of ceramic tile-firing and frit-melting processes, are identified. A summary table is shown, which lists the characteristics, as well as the most significant origin of the main particles identified in the fine (<2.5 µm) airborne particles collected inside primary schools located in three different environments (urban, industrial and rural). A visual scale has been established based on the number of particles observed in the samples of the atmospheric particulate fraction between the sizes of 2.5 and 10 µm collected inside the schools. The ratios Ca/Si, S/Si, S/Ca and (Si+Ca)/S have been established. Results obtained may be useful in epidemiological studies in the ceramic cluster area in order to estimate children's exposure to different indoor primary school microenvironments. Effective policies and mitigation measurements for the protection of children's health should be carried out in this highly industrialized area.

Beyond survival experiments: using biomarkers of oxidative stress and neurotoxicity to assess vulnerability of subterranean fauna to climate change.

Accurate assessments of species vulnerability to climate change need to consider the physiological capacity of organisms to deal with temperature changes and identify early signs of thermally induced stress. Oxidative stress biomarkers and acetylcholinesterase activity are useful proxies of stress at the cellular and nervous system level. Such responses are especially relevant for poor dispersal organisms with limited capacity for behavioural thermoregulation, like deep subterranean species. We combined experimental measurements of upper lethal thermal limits, acclimation capacity and biomarkers of oxidative stress and neurotoxicity to assess the impact of heat stress (20°C) at different exposure times (2 and 7 days) on the Iberian endemic subterranean beetle Parvospeonomus canyellesi. Survival response (7 days of exposure) was similar to that reported for other subterranean specialist beetles (high survival up to 20°C but no above 23°C). However, a low physiological plasticity (i.e. incapacity to increase heat tolerance via acclimation) and signs of impairment at the cellular and nervous system level were observed after 7 days of exposure at 20°C. Such sublethal effects were identified by significant differences in total antioxidant capacity, glutathione S-transferase activity, the ratio of reduced to oxidized forms of glutathione and acetylcholinesterase activity between the control (cave temperature) and 20°C treatment. At 2 days of exposure, most biomarker values indicated some degree of oxidative stress in both the control and high-temperature treatment, likely reflecting an initial altered physiological status associated to factors other than temperature. Considering these integrated responses and the predicted increase in temperature in its unique locality, P. canyellesi would have a narrower thermal safety margin to face climate change than that obtained considering only survival experiments. Our results highlight the importance of exploring thermally sensitive processes at different levels of biological organization to obtain more accurate estimates of the species capacity to face climate change.

The relationship between indoor and outdoor levels of PM10 and its chemical composition at schools in a coastal region in Spain.

PM10 levels and its chemical composition were studied inside and outdoor of seven primary schools (3 in urban environment, 3 in industrial environment, 1 in rural environment) located in the Mediterranean coast in an area with an important industrial nucleus dedicated to the treatment of raw mineral materials. The main objective of this work is a comparison between these levels obtained inside and outside schools and also asses the influence of various natural and anthropogenic emission sources on particles concentrations found inside. The indoor airborne samples were collected using RespiCon TM. In the three outdoor sampling stations was used a minivol air sampler type 3.1 LVS of Derenda. PM10 Chemical composition was obtained by ICP-MS (elements) and ion chromatography The ratio I/O (indoor/outdoor) has been calculated taking into account only the samples taken in the same conditions. In all schools the ratio I/O for PM10 was greater than unity (between 1.3 and 7.8), indicating that existed significant indoor sources of these particles. In the three schools located in the industrial environment were collected PM10 samples inside and outside in non-teaching periods. Comparing the values of I/O when the classrooms were unoccupied with respect to the average value of these same schools when the classrooms are occupied, the behaviour is different depending on the location. On the other hand, a sample in an industrial school was obtained when some infrastructure works were being carried out outside of school. This caused a significant increase in the concentration of particles in the interior (I/O = 19.9). From the levels of As, Ni, Cd, Pb, Al, B, Zn, Mg, Sb, F-, ClO2-, NO3- and SO4 2- in PM10 inside and outside of each school, also the ratios I/O were calculated. These chemical ratios I/O were higher than unity in all cases and generally higher than those recorded in the case of PM10. Finally, Pearson correlation coefficients (r) between the elements and anions and the PM10, and between the different elements and anions were calculated for the purpose of establishing the existence of common emission sources.

Role of cuticle hydrocarbons composition in the salinity tolerance of aquatic beetles.

Salinity tolerance has enabled the colonization of inland saline waters and promoted species diversification in some lineages of aquatic insects. However, the mechanisms behind this tolerance, particularly the role of cuticle hydrocarbons (CHCs), are not well-known. We characterized the CHC profile of eight species of two water beetle genera (Nebrioporus, Adephaga: Dytiscidae and Enochrus, Polyphaga: Hydrophilidae), which span the fresh-hypersaline gradient, to: i) determine the interspecific variation of CHC composition in relation to species' salinity tolerance; ii) explore plastic adjustments in CHC profiles in response to salinity changes at the intraspecific level in saline-tolerant species. CHC profiles were highly species-specific, more complex and diverse in composition, and characterized by longer-chain-length compounds in the species with higher salinity tolerance within each genus. Higher salinity tolerance in the Enochrus species was also associated with an increase in the relative abundance of branched alkanes, and with a lower proportion of n-alkanes and unsaturated compounds. These CHC characteristics are related with improved waterproofing capacity and suggest that reducing cuticle permeability was one of the key mechanisms to adapt to saline waters. Similar CHC composition patterns were found at the intraspecific level between populations from lower and higher salinity sites within saline-tolerant species of each genus. These saline species also displayed an extraordinary ability to adjust CHC profiles to changing salinity conditions in the laboratory in a relatively short time, which reflects great plasticity and a high potential to deal with daily and seasonal environmental fluctuations in the highly dynamic saline habitats.

Heat tolerance and acclimation capacity in subterranean arthropods living under common and stable thermal conditions.

Cave-dwelling ectotherms, which have evolved for millions of years under stable thermal conditions, could be expected to have adjusted their physiological limits to the narrow range of temperatures they experience and to be highly vulnerable to global warming. However, most of the few existing studies on thermal tolerance in subterranean invertebrates highlight that despite the fact that they show lower heat tolerance than most surface-dwelling species, their upper thermal limits are generally not adjusted to ambient temperature. The question remains to what extent this pattern is common across subterranean invertebrates. We studied basal heat tolerance and its plasticity in four species of distant arthropod groups (Coleoptera, Diplopoda, and Collembola) with different evolutionary histories but under similar selection pressures, as they have been exposed to the same constant environmental conditions for a long time. Adults were exposed at different temperatures for 1 week to determine upper lethal temperatures. Then, individuals from previous sublethal treatments were transferred to a higher temperature to determine acclimation capacity. Upper lethal temperatures of three of the studied species were similar to those reported for other subterranean species (between 20 and 25°C) and widely exceeded the cave temperature (13-14°C). The diplopod species showed the highest long-term heat tolerance detected so far for a troglobiont (i.e., obligate subterranean) species (median lethal temperature after 7 days exposure: 28°C) and a positive acclimation response. Our results agree with previous studies showing that heat tolerance in subterranean species is not determined by environmental conditions. Thus, subterranean species, even those living under similar climatic conditions, might be differently affected by global warming.

Insect communities in saline waters consist of realized but not fundamental niche specialists.

Considering how organisms adapt to stress is essential if we are to anticipate biological responses to global change in ecosystems. Communities in stressful environments can potentially be assembled by specialists (i.e. species that only occur in a limited range of environmental conditions) and/or generalist species with wider environmental tolerances. We review the existing literature on the salinity tolerance of aquatic insects previously identified as saline specialists because they were exclusively found in saline habitats, and explore if these saline realized niche specialists are also specialists in their fundamental niches or on the contrary are fundamental niche generalist species confined to the highest salinities they can tolerate. The results suggest that species inhabiting saline waters are generalists in their fundamental niches, with a predominant pattern of high survival in freshwater-low salinity conditions, where their fitness tends to be similar or even higher than in saline waters. Additionally, their performance in freshwater tends to be similar to related strictly freshwater species, so no apparent trade-off of generalization is shown. These results are discussed in the framework of the ecological and evolutionary processes driving community assembly across the osmotic stress gradient, and their potential implications for predicting impacts from saline dilution and freshwater salinization.This article is part of the theme issue 'Salt in freshwaters: causes, ecological consequences and future prospects'.

Effects of salinity changes on aquatic organisms in a multiple stressor context.

Under global change, the ion concentration of aquatic ecosystems is changing worldwide. Many freshwater ecosystems are being salinized by anthropogenic salt inputs, whereas many naturally saline ones are being diluted by agricultural drainages. This occurs concomitantly with changes in other stressors, which can result in additive, antagonistic or synergistic effects on organisms. We reviewed experimental studies that manipulated salinity and other abiotic stressors, on inland and transitional aquatic habitats, to (i) synthesize their main effects on organisms' performance, (ii) quantify the frequency of joint effect types across studies and (iii) determine the overall individual and joint effects and their variation among salinity-stressor pairs and organism groups using meta-analyses. Additive effects were slightly more frequent (54%) than non-additive ones (46%) across all the studies (n = 105 responses). However, antagonistic effects were dominant for the stressor pair salinity and toxicants (44%, n = 43), transitional habitats (48%, n = 31) and vertebrates (71%, n = 21). Meta-analyses showed detrimental additive joint effects of salinity and other stressors on organism performance and a greater individual impact of salinity than the other stressors. These results were consistent across stressor pairs and organism types. These findings suggest that strategies to mitigate multiple stressor impacts on aquatic ecosystems should prioritize restoring natural salinity concentrations.This article is part of the theme issue 'Salt in freshwaters: causes, ecological consequences and future prospects'.

Relationship between motivational climate, sportspersonship and disposition to cheating in young soccer players

heating in young soccer players. Participants were 197 soccer players aged between 13 and 19 from a club in Barcelona. Cuestionario deDisposición al Engaño en el Deporte (CDED), Multidimensional Sportspersonship Orientations Scale (MSOS) and Empowering and DisempoweringMotivational Climate Questionnaire (EDMCQ-C) were administered. Results showed that the perception of an empowering climate is linked to prosocialbehaviors (i.e., sportspersonship). Contrary, a perception of a disempowering climate is linked to the acceptance of antisocial behaviors (i.e., cheatingand gamesmanship). Moreover, gamesmanship behaviors are more accepted than cheating. This enlightens the importance of the coach-createdmotivational climate as an aspect that can influence in the player

The chicken or the egg? Adaptation to desiccation and salinity tolerance in a lineage of water beetles.

Transitions from fresh to saline habitats are restricted to a handful of insect lineages, as the colonization of saline waters requires specialized mechanisms to deal with osmotic stress. Previous studies have suggested that tolerance to salinity and desiccation could be mechanistically and evolutionarily linked, but the temporal sequence of these adaptations is not well established for individual lineages. We combined molecular, physiological and ecological data to explore the evolution of desiccation resistance, hyporegulation ability (i.e., the ability to osmoregulate in hyperosmotic media) and habitat transitions in the water beetle genus Enochrus subgenus Lumetus (Hydrophilidae). We tested whether enhanced desiccation resistance evolved before increases in hyporegulation ability or vice versa, or whether the two mechanisms evolved in parallel. The most recent ancestor of Lumetus was inferred to have high desiccation resistance and moderate hyporegulation ability. There were repeated shifts between habitats with differing levels of salinity in the radiation of the group, those to the most saline habitats generally occurring more rapidly than those to less saline ones. Significant and accelerated changes in hyporegulation ability evolved in parallel with smaller and more progressive increases in desiccation resistance across the phylogeny, associated with the colonization of meso- and hypersaline waters during global aridification events. All species with high hyporegulation ability were also desiccation-resistant, but not vice versa. Overall, results are consistent with the hypothesis that desiccation resistance mechanisms evolved first and provided the physiological basis for the development of hyporegulation ability, allowing these insects to colonize and diversify across meso- and hypersaline habitats.

Cuticle hydrocarbons in saline aquatic beetles.

Hydrocarbons are the principal component of insect cuticle and play an important role in maintaining water balance. Cuticular impermeability could be an adaptative response to salinity and desiccation in aquatic insects; however, cuticular hydrocarbons have been poorly explored in this group and there are no previous data on saline species. We characterized cuticular hydrocarbons of adults and larvae of two saline aquatic beetles, namely Nebrioporus baeticus (Dytiscidae) and Enochrus jesusarribasi (Hydrophilidae), using a gas chromatograph coupled to a mass spectrometer. The CHC profile of adults of both species, characterized by a high abundance of branched alkanes and low of unsaturated alkenes, seems to be more similar to that of some terrestrial beetles (e.g., desert Tenebrionidae) compared with other aquatic Coleoptera (freshwater Dytiscidae). Adults of E. jesusarribasi had longer chain compounds than N. baeticus, in agreement with their higher resistance to salinity and desiccation. The more permeable cuticle of larvae was characterized by a lower diversity in compounds, shorter carbon chain length and a higher proportion of unsaturated hydrocarbons compared with that of the adults. These results suggest that osmotic stress on aquatic insects could exert a selection pressure on CHC profile similar to aridity in terrestrial species.