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.Peer reviewe

Efectos de diferentes intensidades del entrenamiento de lafuerza sobre los parámetros relacionados con la salud en la atracción hacia la actividad física de las personas mayores

To assess the effects of a progressive resistance training program at different intensities on health-related quality of life, anxiety, and motivation towards engaging in physical activity among older people. Prospective, municipal multi-centers, non-randomized controlled trial. 76 older adults were assigned to: vigorous intensity (n = 19), vigorous-moderate intensity (n = 21), moderate intensity (n = 19), or control group (n = 17). The exercise groups performed six exercises with elastic bands per session, twice a week, for 8 months. Vigorous intensity, vigorous-moderate intensity and moderate intensity group performed 6, 10 and 15 repetitions, respectively. Health-related quality of life was assessed using the 36-Item Short Form Health Survey, trait and state anxiety using the State-Trait Anxiety Inventory, and motivation towards engaging in physical activity using the Behavioural Regulation in Exercise Questionnaire. The moderate intensity group showed a significant increase in the summary of the physical components of health-related quality of life (p = 0.001; ηp2 = 0.158) and a significant decrease in external regulation (p = 0.002; ηp2= 0.145) and amotivation (p = 0.013; ηp2 = 0.97). In contrast, the vigorous intensity group showed a significant increase in state anxiety (p = 0.004; ηp2 = 0.076) and a significant decrease in introjected regulation (p = 0.018; ηp2 = 0.097). Moderate intensity strength training programs are best suited for older adults because they improve health-related quality of life and decrease less self-determined forms of regulation, all without increasing anxiety states.Evaluar los efectos de un programa de entrenamiento progresivo de la fuerza a diferentes intensidades sobre la calidad de vida relacionada con la salud, la ansiedad y la motivación para atraer hacia la realización de actividad física entre las personas mayores. Ensayo controlado prospectivo, multicéntrico municipal, no aleatorizado. 76 adultos mayores fueron asignados a: grupo de intensidad vigorosa (n = 19), vigorosa-moderada (n = 21), moderada (n = 19), o grupo de control (n = 17). Los grupos de ejercicio realizaron seis ejercicios con bandas elásticas por sesión, dos veces por semana, durante 8 meses. Los grupos de intensidad vigorosa, vigorosa-moderada y moderada realizaron 6, 10 y 15 repeticiones, respectivamente. La calidad de vida relacionada con la salud se evaluó mediante la Encuesta de Salud de formulario corto de 36 elementos, el rasgo y el estado de ansiedad mediante el Inventario de Ansiedad Estado-Rasgo, y la motivación para realizar actividad física mediante el Cuestionario de Regulación del Comportamiento en el Ejercicio. El grupo de intensidad moderada mostró un aumento significativo en el resumen de los componentes físicos de la calidad de vida relacionada con la salud (p = 0.001; ηp2 = 0.158) y una disminución significativa en la regulación externa (p = 0.002; ηp2 = 0.145) y desmotivación (p = 0.013; ηp2 = 0.97). En contraste, el grupo de intensidad vigorosa mostró un aumento significativo en el estado de ansiedad (p = 0.004; ηp2 = 0.076) y una disminución significativa en la regulación introyectada (p = 0.018; ηp2 = 0.097). Los programas de entrenamiento de la fuerza de intensidad moderada son más adecuados para los adultos mayores porque mejoran la calidad de vida relacionada con la salud y disminuyen las formas de regulación menos autodeterminadas, todo sin aumentar los estados de ansiedad.Actividad Física y Deport

Glutaminase and MMP-9 downregulation in cortex and hippocampus of LPA1 receptor null mice correlate with altered dendritic spine plasticity

Lysophosphatidic acid (LPA) is an extracellular lipid mediator that regulates nervous system development and functions acting through G protein-coupled receptors (GPCRs). Here we explore the crosstalk between LPA1 receptor and glutamatergic transmission by examining expression of glutaminase (GA) isoforms in different brain areas isolated from wild-type (WT) and KOLPA1 mice. Silencing of LPA1 receptor induced a severe down-regulation of Gls-encoded long glutaminase protein variant (KGA) (glutaminase gene encoding the kidney-type isoforms, GLS) protein expression in several brain regions, particularly in brain cortex and hippocampus. Immunohistochemical assessment of protein levels for the second type of glutaminase (GA) isoform, glutaminase gene encoding the liver-type isoforms (GLS2), did not detect substantial differences with regard to WT animals. The regional mRNA levels of GLS were determined by real time RT-PCR and did not show significant variations, except for prefrontal and motor cortex values which clearly diminished in KO mice. Total GA activity was also significantly reduced in prefrontal and motor cortex, but remained essentially unchanged in the hippocampus and rest of brain regions examined, suggesting activation of genetic compensatory mechanisms and/or post-translational modifications to compensate for KGA protein deficit. Remarkably, Golgi staining of hippocampal regions showed an altered morphology of glutamatergic pyramidal cells dendritic spines towards a less mature filopodia-like phenotype, as compared with WT littermates. This structural change correlated with a strong decrease of active matrix-metalloproteinase (MMP) 9 in cerebral cortex and hippocampus of KOLPA1 mice. Taken together, these results demonstrate that LPA signaling through LPA1 influence expression of the main isoenzyme of glutamate biosynthesis with strong repercussions on dendritic spines maturation, which may partially explain the cognitive and learning defects previously reported for this colony of KOLPA1 mice

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.Peer reviewe

Cambio climático, nicho térmico y conservación de la biodiversidad subterránea

Predecir los efectos del cambio climático y diseñar estrategias efectivas de conservación de la biodiversidad son dos de los grandes retos actuales para la comunidad científica. El medio subterráneo es uno de los pocos ecosistemas donde, por sus condiciones ambientales constantes, se pueden obtener predicciones precisas de la respuesta de sus especies al cambio climático. Además, está directamente conectado a la superficie, viéndose afectado por diversas amenazas humanas que han desencadenado procesos de alteración que están provocando la pérdida de biodiversidad subterránea. Por lo tanto, es urgente evaluar si las redes de espacios protegidos actuales son efectivas para la protección de la biodiversidad subterránea. Los objetivos generales de esta tesis son: i) predecir la vulnerabilidad de la biodiversidad subterránea frente al cambio climático, combinando información sobre la fisiología térmica, ecología y relaciones evolutivas de diferentes especies de invertebrados subterráneos de varios grupos y de distintas áreas geográficas, y ii) evaluar la efectividad de las redes de espacios protegidos para conservar la biodiversidad subterránea. La tesis se estructura en 4 objetivos específicos: En el objetivo 1, se estimó el límite térmico superior de un pseudoescorpión subterráneo utilizando dos metodologías diferentes: i) a partir de las condiciones climáticas de sus localidades actuales y ii) a partir de experimentos fisiológicos. Los resultados del primer método muestran que, el riesgo de extinción local podría ser alto para al menos la mitad de las poblaciones de la especie estudiada. Este mensaje alarmante puede atenuarse al considerar los resultados de los experimentos fisiológicos, mostrando que enfoques complementarios para estimar la tolerancia térmica proporcionan predicciones más precisas de la capacidad de las especies de afrontar el cambio climático. En el objetivo 2, se determinó la plasticidad del límite térmico superior de 3 escarabajos con diferente grado de especialización al medio subterráneo sometidos a distintos tratamientos de aclimatación. Se demostró que las especies más especializadas al medio subterráneo profundo carecen de capacidad de aclimatación. Sin embargo, la especie menos especializada es capaz de aumentar los límites térmicos superiores tras unos días expuesta a mayor temperatura. En el objetivo 3, se estimó el límite térmico superior de 16 escarabajos subterráneos, se caracterizó su grado especialización al medio subterráneo utilizando rasgos morfológicos y ecológicos, y se obtuvieron datos de la temperatura del hábitat de cada especie. Los resultados muestran que las especies altamente especializadas tienen menor tolerancia al calor, independientemente de la temperatura media de su hábitat. Por lo tanto, la vulnerabilidad de las especies subterráneas frente al cambio climático dependerá en gran medida de su grado de especialización al medio subterráneo profundo. En el objetivo 4, se generó una base de datos de distribución de especies subterráneas de dos grupos taxonómicos (escarabajos y arañas) en dos puntos calientes de biodiversidad subterránea (Pirineos y Alpes), se identificaron áreas prioritarias para su conservación, y por último se evaluó hasta qué punto están incluidas en las redes de áreas protegidas superficiales. Más del 70 y el 90% de las áreas prioritarias para la conservación de la biodiversidad subterránea (y el 40 y el 22% de las especies) no están efectivamente cubiertas por zonas protegidas en los Pirineos y los Alpes, respectivamente. Además, se identificaron 49 cuencas más en los Pirineos y 22 en los Alpes que sería necesario proteger para cubrir a todas las especies que actualmente se encuentran fuera de espacios protegidos. Estos resultados ponen de manifiesto la urgente necesidad de desarrollar un plan coherente de conservación de la biodiversidad subterránea.Predicting the effects of climate change and designing effective biodiversity conservation strategies are two major challenges for the scientific community. The subterranean environment is one of the few ecosystems where, due to its constant environmental conditions, it is possible to obtain accurate predictions of the species response to climate change. Moreover, it is directly connected to the surface and consequently, affected by several human threats that have triggered alteration processes leading to the loss of subterranean biodiversity. It is therefore urgent to assess how far the current networks of protected areas are effective for the protection of subterranean biodiversity. The main objectives of this thesis are: i) to predict the vulnerability of subterranean biodiversity to climate change, combining information on the thermal physiology, ecology and evolutionary relationships of different subterranean species from several taxonomic groups and study areas, and ii) to assess the effectiveness of protected area networks in conserving subterranean biodiversity. The thesis is structured in 4 specific objectives: In the objective 1, the physiological upper thermal limit of a subterranean pseudoscorpion was estimated following two different approaches: i) from climatic data in its current localities; and ii) from physiological experiments. The results show that, according to the first method, the risk of local extinction could be high for at least half of the populations of the species studied. This alarming message can be mitigated by considering the results of the physiological experiments, which shows that complementary approaches to estimating thermal tolerance provide more accurate predictions of the species' ability to cope with climate change. In the objective 2, the plasticity of the upper thermal limit of 3 beetles with different degrees of subterranean specialization, exposed to different acclimation treatments, was determined. The most specialized species to the deep subterranean environment lacked acclimation capacity. However, the least specialized species was able to increase the upper thermal limits after a few days of exposure to higher temperature. In the objective 3, the upper thermal limit of 16 subterranean beetles was estimated, their degree of specialization to the subterranean environment was characterized using morphological and ecological traits, and habitat temperature data were obtained for each species. The results show that highly specialized species have lower heat tolerance than less specialized ones, regardless of the mean temperature of their habitat. Therefore, the vulnerability of subterranean species to climate change will greatly depend on their degree of specialization to the deep subterranean environment. In the objective 4, a distribution database of subterranean species of two taxonomic groups (beetles and spiders) in two subterranean biodiversity hotspots (the Pyrenees and the Alps) was compiled in order to i) identify priority areas for their conservation, as well as ii) to assess the extent to which they are covered by surface protected areas. More than 70 and 90% of the priority areas for subterranean biodiversity conservation (and 40 and 22% of the species) are not effectively covered by protected areas in the Pyrenees and the Alps, respectively. In addition, forty-nine more hydrographic basins were identified in the Pyrenees and 22 in the Alps that would need to be protected to cover all species that currently are outside protected areas. These results highlight the urgent need to develop a coherent plan for the conservation of subterranean biodiversity

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

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

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

Este artículo esta en el repositorio recercat.cat en abierto, envío correo a su responsable Miguel Navas [email protected] para que me informe como ha interpretado el las condiciones que nos dice Sherpa. Hablo con la autora y queda a la espera de que le informe 666172772 • Esta revista no permite la publicación de la versión aceptada, que es ésta. • Departamento de Ecología e Hidrología Enviado correo a la autora. FALTA LA FRASE© 2021 Ecological Society of America. This manuscript version is made available under the CC-BY-4.0 license http://creativecommons.org/licenses/by/4.0/ This document is the Published Manuscript version of a Published Work that appeared in final form in Ecology. To access the final edited and published work see DOI: 10.1002/ecy.3629The 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

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 higherature 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.This work was supported by the Agencia Estatal de Investigación (Spain), the Spanish Ministry of Economy and Competitiveness and the European Regional Development Fund [project CGL2016-76995-P]. S.P. is funded by a postdoctoral grant from Fundación Seneca - Agencia de Ciencia y Tecnología de la Región de Murcia (Spain), D.S-F is funded by a postdoctoral grant from the University of Murcia (Spain) and R.C. and P.B-G are funded by predoctoral grants from the Spanish Ministry of Science, Innovation and Universitie