197 research outputs found

    Behavioural thermoregulation in cold-water freshwater fish: Innate resilience to climate warming?

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    Behavioural thermoregulation enables ectotherms to access habitats providing condi-tions within their temperature optima, especially in periods of extreme thermal condi-tions, through adjustments to their behaviours that provide a “whole- body” response to temperature changes. Although freshwater fish have been detected as moving in response to temperature changes to access habitats that provide their thermal optima, there is a lack of integrative studies synthesising the extent to which this is driven by behaviour across different species and spatial scales. A quantitative global synthesis of behavioural thermoregulation in freshwater fish revealed that across 77 studies, behavioural thermoregulatory movements by fish were detected both vertically and horizontally, and from warm to cool waters and, occasionally, the converse. When fish moved from warm to cooler habitats, the extent of the temperature difference between these habitats decreased with increasing latitude, with juvenile and non- migratory fishes tolerating greater temperature differences than adult and anadro-mous individuals. With most studies focused on assessing movements of cold-water salmonids during summer periods, there remains an outstanding need for work on cli-matically vulnerable, non-salmonid fishes to understand how these innate thermoreg-ulatory behaviours could facilitate population persistence in warming conditions

    Variability in the summer movements, habitat use and thermal biology of two fish species in a temperate river

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    The ability of fish to cope with warm water temperatures in summer depends on factors including their thermal traits and the ability of individuals to access cool-water refugia. Knowledge is highly limited on the in situ responses of many fishes to elevated summer temperatures, including whether they express behavioural thermoregulation. The responses of two riverine species to summer water temperatures were tested here using the movement metrics, spatial habitat use and body temperatures of individual European barbel Barbus barbus (‘barbel’) and common bream Abramis brama (‘bream’) versus river temperatures. Acoustic biotelemetry was applied in the lower River Severn basin, western Britain, in summer 2021 (barbel) and 2022 (bream), where individuals could move across > 150 km of river, including a tributary of cooler water. Across all individuals, bream occupied 37 km of river length (mainstem only), with low inter-individual variability in their spatial habitat use, movements and body temperatures. In contrast, barbel occupied 62 km of river (main river/tributary), with relatively high inter-individual variability in spatial habitat use, movements and body temperatures, with higher variation in body temperatures as river temperatures increased (maximum mean daily temperature difference between individuals on the same day: 4.2 °C). Although warmer individuals generally moved more, their activity was greatest at relatively low temperatures and higher flows, and neither species revealed any evidence of behavioural thermoregulation during elevated temperatures. Enabling phenotypically diverse fish populations to express their natural behaviours and thermal preferences in summer water temperatures thus requires maintaining their free-ranging in thermally heterogenous habitats

    Climate change adaptation for biodiversity in protected areas: An overview of actions

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    Protected Areas (PAs) have been a cornerstone of conservation policy in the past but are generally static and thus might be less useful under climate change as species move away from reserves designated for them. In addition, shifting phenology and habitat alteration due to extreme events could make conditions unviable within PAs for species unable to move. However, several recent papers documented their utility in retaining contracting species, acting as stepping-stones for expanding species of conservation concern and resisting invasion by vagrants. Theoretical studies have suggested a role for both protected area design and management to enable biodiversity to adapt to climate change and implementation of these actions has begun. Here we synthesise case studies of climate change adaptation actions in protected areas from the globally available literature. We found 91 case studies of 114 different actions from 30 countries, mostly within Europe, specifically the UK. Half reported an outcome of actions, however, these were generally either the area restored or protected, or incidental reports of colonisation by desired species, without a description of monitoring before and after action. In addition, 72 % of actions would have been beneficial to biodiversity without the presence of climate change, so transformative action is lacking. Better monitoring and reporting of outcomes are urgently needed to develop the evidence base on which actions are most effective, to enable more reserve managers to take action. Managers also need encouragement to identify transformative actions, perhaps by the use of scenario planning to aid understanding of future uncertainties

    The AST3-NIR Camera for the Kunlun Infrared Sky Survey

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    AST3-NIR is a new infrared camera for deployment with the AST3-3 wide-field survey telescope to Dome A on the Antarctic plateau. This project is designed to take advantage of the low Antarctic infrared sky thermal background (particularly within the Kdark near infrared atmospheric window at 2.4 μm) and the long Antarctic nights to provide high sensitivity temporal data from astronomical sources. The data collected from the Kunlun Infrared Sky Survey (KISS) will be used to conduct a range of astronomical science cases including the study of supernovae, exo-planets, variable stars, and the cosmic infrared background

    Asymmetry of Early Endosome Distribution in C. elegans Embryos

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    development, we examined the distribution and dynamics of early endosomes (EEs) in embryos.EEs are primarily found at the cell periphery with an initially uniform distribution after fertilization. Strikingly, we find that during the first cell cycle, EEA-1 positive EEs become enriched at the anterior cortex. In contrast, the Golgi compartment shows no asymmetry in distribution. Asymmetric enrichment of EEs depends on acto-myosin contractility and embryonic PAR polarity. In addition to their localization at the cortex, EEs are also found around the centrosome. These EEs move rapidly (1.3um/s) from the cortex directly to the centrosome, a speed comparable to that of the minus end directed motor dynein.We speculate that the asymmetry of early endosomes might play a role in cell asymmetries or fate decisions

    Multidimensional apathy and executive dysfunction in amyotrophic lateral sclerosis

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    Apathy and cognitive dysfunction are prominent symptoms of Amyotrophic lateral sclerosis (ALS). More specifically ALS patients show increased Initiation apathy-a lack of motivation for self-generation of thoughts as assessed by the Dimensional Apathy Scale. This study aimed to investigate the cognitive underpinnings of apathy subtypes in ALS. We hypothesized that increased Initiation apathy would be associated deficits on tests of intrinsic response generation, such as verbal fluency. We also explored the relationship of other apathy subtypes to cognitive processes, in particular emotional apathy with emotional and social cognition deficits and executive apathy with planning and goal management deficits. ALS patients, and their carers (N = 30), and healthy matched controls, and their informants (N = 29) were recruited. All participants completed self- and informant/carer-rated Dimensional Apathy Scale, to quantify apathy subtypes (Executive, Emotional and Initiation), along with standard apathy and depression measures. Patients and controls completed the Edinburgh Cognitive and behavioural ALS Screen, and a comprehensive neuropsychological battery including emotional recognition, social cognition, intrinsic response generation tasks (verbal fluency and random number generation) and a new ecologically valid, computerised measure of planning and goal management. The results demonstrated that increased Initiation apathy was the only significantly elevated subtype in ALS (self-rated p < .05, informant/carer-rated p < .01). Initiation apathy was found to be significantly associated with verbal fluency deficit, while Emotional apathy was significantly associated with emotional recognition deficits. No associations were found between apathy subtypes and depression or in controls. This is the first study to show specific associations between apathy subtypes (Emotional and Initiation) and executive and emotional cognitive dysfunction, indicating possible distinct underlying mechanisms to these demotivational symptoms
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