Of telomeres and temperature: Measuring thermal effects on telomeres in ectothermic animals

Molecular Ecology, Journal Year: 2021, Volume and Issue: 31(23), P. 6069 - 6086

Published: Aug. 27, 2021

Ectotherms are classic models for understanding life-history tradeoffs, including the reproduction-somatic maintenance tradeoffs that may be reflected in telomere length and their dynamics. Importantly, traits of ectotherms tightly linked to thermal environment, with diverse or synergistic mechanistic explanations underpinning variation. Telomere dynamics potentially provide a link can used monitor effects on individuals response climatic perturbations. Growth rate, age developmental stage all affected by temperature, which interacts complex intriguing ways. The physiological processes visualized understood using performance curves (TPCs). TPCs reflect evolutionary history environment during an individual's ontogeny. should enhanced at near optimum species, population individual. sensitivity interacting underlying them. key directly mitochondrial function (reactive oxygen production), antioxidant activity, telomerase activity endcap protein status. We argue identifying these will significantly help design robust, repeatable experiments field studies ectotherms. Conceptually, valuable framework predict interpret taxon- population-specific across regimes. literature telomeres is sparse mostly limited vertebrates, but our conclusions recommendations relevant ectothermic animals.

Language: Английский

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Living in Hot Sand: The Thermal Biology of Scincus scincus, the Sandfish Skink

Journal of Herpetology, Journal Year: 2025, Volume and Issue: 58(4)

Published: Jan. 29, 2025

Language: Английский

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Comprehensive thermal performance curves for yellow dung fly life history traits and the temperature-size-rule

Journal of Thermal Biology, Journal Year: 2021, Volume and Issue: 100, P. 103069 - 103069

Published: Aug. 1, 2021

Ambient temperature strongly determines the behaviour, physiology, and life history of all organisms. The technical assessment organismal thermal niches in form now so-called performance curves (TPC) thus has a long tradition biological research. Nevertheless, several traits do not display idealized, intuitive dome-shaped TPC, practice assessments often cover entire realistic or natural range an organism. We here illustrate this by presenting comprehensive sex-specific TPCs for major (juvenile) yellow dung flies (Scathophaga stercoraria; Diptera: Scathophagidae). This concerns estimation prominent biogeographic rules, such as temperature-size-rule (TSR), common phenomenon ectothermic organisms that body size decreases increases. S. stercoraria shows untypical asymptotic TPC continuous increase with decreasing without peak (optimum), following TSR throughout their (unlike other insects presented here). Egg-to-adult mortality (our best fitness estimator) also no intermediate maximum. Both may relate to fly entering pupal winter diapause below 12 °C. While development time presents negative exponential relationship temperature, rate growth typify classic fly. hitherto largely unexplored close relative suilla even more arctic distribution showed very similar responses, demonstrating large overlap among two ecologically similar, coexisting species, implying limited utility complete predicting species coexistence.

Language: Английский

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From performance curves to performance surfaces: Interactive effects of temperature and oxygen availability on aerobic and anaerobic performance in the common wall lizard

Functional Ecology, Journal Year: 2022, Volume and Issue: 36(10), P. 2544 - 2557

Published: July 19, 2022

Abstract Accurately predicting the responses of organisms to novel or changing environments requires development ecologically‐appropriate experimental methodology and process‐based models. For ectotherms, thermal performance curves (TPCs) have provided a useful framework describe how organismal is dependent on temperature. However, this approach often lacks mechanistic underpinning, which limits our ability use TPCs predictively. Furthermore, dependence varies across traits, also limited by additional abiotic factors, such as oxygen availability. We test central prediction recent Hierarchical Mechanisms Thermal Limitation (HMTL) Hypothesis proposes that natural hypoxia exposure will reduce maximal cause TPC for whole‐organism become more symmetrical. quantified two traits used fitness proxies, sprint speed aerobic scope, in lizards under conditions normoxia high‐elevation hypoxia. In line with predictions HMTL, anaerobically fuelled was unaffected acute while scope became shorter This change shape resulted from both maximum optimal temperature being reduced predicted. Following these results, we present mathematical framework, call Temperature–Oxygen Performance Surfaces, quantify interactive effects HMTL hypothesis. transferrable levels organization allow ectotherms respond combinations other providing tool time rapidly environmental conditions. Read free Plain Language Summary article Journal blog.

Language: Английский

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There and back again: A meta-analytical approach on the influence of acclimation and altitude in the upper thermal tolerance of amphibians and reptiles

Frontiers in Ecology and Evolution, Journal Year: 2022, Volume and Issue: 10

Published: Nov. 4, 2022

Realistic predictions about the impacts of climate change onbiodiversity requires gathering ecophysiological data and critical thermal maxima (CTMax) is most frequently used index to assess vulnerability species. In present study, we performed a systematic review understand how acclimation altitude affect CTMax estimates for amphibian non-avian reptile We retrieved anurans, salamanders, lizards, snakes, turtles/terrapins. Data allowed perform multilevel random effects meta-analysis answer temperature Anura, Caudata, Squamata also meta-regressions influence on frogs lizards. Acclimation influenced tadpoles, adult but not froglets. general, increase in led higher values. Altitudinal bioclimatic gradient had an inverse effect estimating lizards anuran amphibians. For was positively by mean wettest quarter. relationship inverse; recover trend decreasing when max warmest month precipitation seasonality increase. There urgent need studies investigate tolerance subsampled groups or even which do have any information such as Gymnophiona, Serpentes, Amphisbaena, Testudines. Broader phylogenetic coverage mandatory more accurate analyses macroecological evolutionary patterns indices CTMax.

Language: Английский

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How Does Mitochondrial Protein-Coding Gene Expression in Fejervarya kawamurai (Anura: Dicroglossidae) Respond to Extreme Temperatures?

Animals, Journal Year: 2023, Volume and Issue: 13(19), P. 3015 - 3015

Published: Sept. 25, 2023

Unusual climates can lead to extreme temperatures. Fejervarya kawamurai, one of the most prevalent anurans in paddy fields tropical and subtropical regions Asia, is sensitive climate change. The present study focuses primarily on a single question: how do 13 mitochondrial protein-coding genes (PCGs) respond temperature change compared with 25 °C controls? Thirty-eight including an extra tRNA-Met gene were identified sequenced from genome F. kawamurai. Evolutionary relationships assessed within Dicroglossidae showed that Dicroglossinae monophyletic kawamurai sister group clade (F. multistriata + limnocharis). Transcript levels liver also evaluated assess responses 24 h exposure low (2 4 °C) or high (40 Under 2 °C, seven significant changes transcript levels, among which ATP8, ND1, ND2, ND3, ND4, Cytb increased, respectively, ND5 decreased. However, for was very different expressions ten genes, except Cytb, significantly downregulated. Among them, level downregulated, decreasing by 0.28-fold. Exposure hot environment at 40 resulted marked difference strong upregulation eight ranging 1.52-fold increase ND4L 2.18-fold rise although COI reduced 0.56 0.67, controls. Overall, these results suggest appears have entered hypometabolic state hibernation, whereas its oxidative phosphorylation affected both °C. majority PCGs exhibited substantial all three temperatures, indicating frogs such as inhabit are susceptible ambient quickly employ compensating adjustments proteins involved electron transport chain.

Language: Английский

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Adaptive thermal responses of captive Nile crocodiles (Crocodylus niloticus) in South Africa

Applied Animal Behaviour Science, Journal Year: 2023, Volume and Issue: 269, P. 106098 - 106098

Published: Oct. 28, 2023

The current study assessed the ambient temperatures, and those selected, by captive adult Nile crocodiles on a commercial farm in South Africa. Non-invasive data capture techniques were developed to ensure natural behaviours not disrupted or altered. Thermal climate data, over summer winter seasons, collected from local weather stations, an on-site Internet of Things system, Mavic 2 Enterprise Dual drone. method this paper transformed relative thermal maps (produced DJI drone) into predictive model which temperatures derived within 2.6°C per pixel processed orthophoto. Crocodile behavioural extracted drone imagery juxtaposed with pen. greatest number counted during early morning flights lowest late afternoon flights. Material (concrete, water, nest, grass/sand) selection varied season, time day daily climatic conditions. back temperature (10.2 - 49.6°C, µ = 30.4°C) ranges fell their positional/environmental (10.6 66.6°C, 28.7°C) range selections. Strong, positive, significant correlations found between crocodile positional for both highlighting ectothermy. Application methodology facilitated inspection potential shortfalls pens design perspective, as well suggestions improvements that would ameliorate discomfort (relating hyperthermia).

Language: Английский

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Unveiling Critical Thermal Limits of Anolis tolimensis (Squamata, Anolidae) across an Elevational Landscape

Current Herpetology, Journal Year: 2024, Volume and Issue: 43(1)

Published: March 1, 2024

Northern Andes Mountains exhibit high elevational fluctuation in thermal conditions for ectotherms. This fluctuating temperature limits the survival, growth, and dispersion of ectothermic organisms. Therefore, lizard species distributed on these mountain landscapes face strong fluctuations. To test potential effect elevation, we characterized critical maximum (CTmax) minimum (CTmin) body time to reach CTmax (Tmax) CTmin (Tmin) individuals Anolis tolimensis, an endemic two cordilleras northern Andean system Colombia. We collected at four elevations (1,600, 1,900, 2,100, 2,200 m asl) measured their under laboratory conditions. also explored role sex size physiological variables. is similar among elevations, but highest elevation (2,200 lowest (5.5±1.0°C) vs (2,100 asl, 8.8±0.8°C; 1,900 8.3±1°C; 1,600 8.3±0.9°C). range narrower (33–34.2°C) than (5.5–8.8°C), tolerance breadth (CTmin values) 28.7°C. Sex may affect response, interaction varies with geography. Critical are conservative or evolutionary labile (CTmin). tolimensis could deal environmental temperatures by thermoregulatory behavior alternative strategy increasing CTmax. Finally, extinction risk evaluation needed vulnerability population second-highest elevation.

Language: Английский

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Thermo-physiological changes and reproductive investment in a liolaemid lizard at the extreme of the slow-fast continuum

Journal of Experimental Biology, Journal Year: 2024, Volume and Issue: 227(12)

Published: June 3, 2024

Gravid female lizards often experience reduced thermal preferences and impaired locomotor performance. These changes have been attributed to the physical burden of clutch, but some authors suggested that they may be due physiological adjustments. We compared biology performance lizard Liolaemus wiegmannii 1 week before after oviposition. found gravid females had a preference 1°C lower than non-gravid females. This was accompanied by change in dependence maximum running speed. The optimum for 2.6°C oviposition after. At relatively low temperatures (22 26°C), speeds were up 31% higher However, at above 26°C, achieved similar (∼1.5 m s-1) regardless reproductive stage. magnitude parameters L. independent relative clutch mass (clutches weighed 89% post-oviposition body mass). suggests are not simply mass, also simultaneously adjusted their own physiology short period order improve allocated energy embryonic development during late Our findings implications understanding mechanisms underlying life histories on fast extreme slow-fast continuum, where exhaustion could play an important role.

Language: Английский

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Thermal Tolerance Plasticity and Dynamics of Thermal Tolerance inEublepharis macularius: Implications for Future Climate-Driven Heat Stress

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 15, 2024

Abstract The intensity and duration of heat waves, as well average global temperatures, are expected to increase due climate change. Heat waves can cause physiological stress reduce fitness in animals. Species overheating risk through phenotypic plasticity, which allows them raise their thermal tolerance limits over time. This mechanism could be important for ectotherms whose body temperatures directly influenced by available environmental temperatures. Geckos a large, diverse group that vary habitats times daily activity, affect how they physiologically adjust waves. Data on physiology scarce reptiles, with only one study geckos. Understanding relationship, is essential understanding some species able or adapt changing In this study, we estimated interaction, the crepuscular gecko, Eublepharis macularius , emerging model reptile biology. After estimating basal 28 geckos, was measured each individual second time at several timepoints (3, 6, 24 h) determine plasticity. We found plasticity (1) does not depend organism, (2) highest after 6 hours from initial shock, (3) negatively mass. Our findings contribute increasing work focused influence biological factors organisms provide data further investigate molecular basis organisms.

Language: Английский

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