Thermal limits along tropical elevational gradients: Poison frog tadpoles show plasticity but maintain divergence across elevation

Journal of Thermal Biology, Journal Year: 2024, Volume and Issue: 120, P. 103815 - 103815

Published: Feb. 1, 2024

Language: Английский

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Greater plasticity in CTmax with increased climate variability among populations of tailed frogs

Proceedings of the Royal Society B Biological Sciences, Journal Year: 2024, Volume and Issue: 291(2034)

Published: Nov. 1, 2024

Temporally variable climates are expected to drive the evolution of thermal physiological traits that enable performance across a wider range temperatures (i.e. climate variability hypothesis, CVH). Spatial variability, however, may mediate this relationship by providing ectotherms with opportunity behaviourally select preferred Bogert effect). These antagonistic forces on explain mixed support for CVH within species despite strong among at larger geographical scales. Here, we test as it relates plasticity in upper limits (critical maximum—CTmax) populations coastal tailed frogs ( Ascaphus truei ). We targeted inhabit spatially homogeneous environments, reducing potentially confounding effects behavioural thermoregulation. found experiencing greater temporal exhibited CTmax, supporting CVH. Interestingly, identified only one site spatial temperature and tadpoles from demonstrated than expected, suggesting thermoregulation can reduce Overall, our results demonstrate role shaping provide baseline understanding impact landscapes.

Language: Английский

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

Insect Science, Journal Year: 2023, Volume and Issue: 31(1), P. 285 - 298

Published: June 27, 2023

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

Language: Английский

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Phenology and plasticity can prevent adaptive clines in thermal tolerance across temperate mountains: The importance of the elevation‐time axis

Ecology and Evolution, Journal Year: 2022, Volume and Issue: 12(10)

Published: Oct. 1, 2022

Abstract Critical thermal limits (CT max and CT min ) decrease with elevation, greater change in , the risk to suffer heat cold stress increasing at gradient ends. A central prediction is that populations will adapt prevailing climatic conditions. Yet, reliable support for such expectation scant because of complexity integrating phenotypic, molecular divergence organism exposure. We examined intraspecific variation neutral 11 microsatellite loci, micro‐ macro‐temperatures larvae from Galician common frog ( Rana parvipalmata across an elevational gradient, assess (1) existence local adaptation through a P ST ‐F comparison, (2) acclimation scope both limits, (3) vulnerability acute stress, measured macro‐ microclimatic scales. Our study revealed significant microgeographic unexpected elevation gradients pond temperatures. However, could not be attributed selection critical were correlated or Differences breeding phenology among resulted exposure higher more variable temperatures mid high elevations. Accordingly, mid‐ high‐elevation had plasticities than lowland populations, but extreme . Thus, our results plasticity phenological shifts may hinder adaptation, promoting niche conservatism. This simply consequence coupled reproductive timing (the “elevation‐time axis” temperature variation). Mid mountain R. are vulnerable cool impacts during aquatic phase. All this contradicts some existing predictions on adaptive clines climate gradients.

Language: Английский

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Invasive frogs show persistent physiological differences to elevation and acclimate to colder temperatures

Journal of Thermal Biology, Journal Year: 2023, Volume and Issue: 114, P. 103590 - 103590

Published: May 1, 2023

Language: Английский

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Physiological thermal niches, elevational ranges and thermal stress in dendrobatid frogs: An integrated approach

Journal of Biogeography, Journal Year: 2024, Volume and Issue: 51(10), P. 1880 - 1893

Published: May 7, 2024

Abstract Aim We investigated the relationship between thermal physiology, elevational distribution and stress among nine closely related dendrobatid frogs during their aquatic stage by employing an integrated approach, combining environmental temperature modelling predictive assessments of current future exposure to variation. Location Ecuador. Taxon Amphibians; Anura, Dendrobatidae, Epipedobates, Hyloxalus. Methods determined performance curves (TPCs) larval growth for each species modelled variation in contrasting environments both present times. This allowed us estimate expected distributions forecast periods stressful temperatures that inhibit due elevation global warming. Results found significant correlations optimum (Topt), 50% maximum (maxB50), minimum (minB50) cold resistance (survival at 9°C) with distributions. However, physiology predicted lower than observed high‐elevation dendrobatids higher elevations lowland species. Nonetheless, our models low variability habitats (i.e. streams deep permanent ponds) can buffer increase all taxa, even when considering most extreme scenario. In contrast, within high (open forest temporary are experience under conditions. Main Conclusions The findings indicate may not be a limiting factor frog species' ranges this equatorial mountain gradient. Highland need adapt suboptimal performance, while some could occupy elevations. study emphasizes importance habitat buffering mitigate face climate change amphibians tropical mountains.

Language: Английский

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Niche Theory and Species Range Limits along Elevational Gradients: Perspectives and Future Directions

Annual Review of Ecology Evolution and Systematics, Journal Year: 2024, Volume and Issue: 55(1), P. 449 - 469

Published: Aug. 14, 2024

Despite two centuries of research, the mechanisms underlying formation species’ elevational range limits remain poorly understood. The climatic variability hypothesis highlights role conditions in shaping thermal tolerance and distribution ranges, while species interactions–abiotic stress underscores relative importance biotic factors abiotic along environmental gradients. We emphasize Darwin's perspective on ubiquity interspecific competition across gradients understanding how climate modulates interactions to shape distributions. Niche theory provides a comprehensive framework, combined with empirical explore influence traits, leading context-dependent that constrain In particular, application concept environmentally weighted performance can further elucidate these complex ecological mechanisms. Future research should integrate multiple approaches, including field laboratory manipulative experiments, theoretical modeling, interdisciplinary collaboration, improve our distributions mountain regions inform biodiversity conservation strategies face rapid change.

Language: Английский

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Intraspecific variation of thermal tolerance along elevational gradients: the case of a widespread diving beetle (Coleoptera: Dytiscidae)

Insect Science, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 25, 2024

Abstract Species distributed across wide elevational gradients are likely to experience local thermal adaptation and exhibit high plasticity, as these characterised by steep environmental changes over short geographic distances (i.e., strong selection differentials). The prevalence of adaptive intraspecific variation in tolerance with elevation remains unclear, however, particularly freshwater taxa. We explored upper lower limits acclimation capacity among Iberian populations adults the widespread water beetle Agabus bipustulatus (Dytiscidae) a 2000 m gradient, from lowland alpine areas. Since mean extreme temperatures decline elevation, we predicted that at higher elevations will show heat cold than ones. also whether is positively related climatic variability elevations. found significant between A. , but no evidence different conditions altitudinal relationships or variables were largely nonsignificant. Furthermore, plasticities both consistently low all populations. These results suggest niche conservatism this species, due gene flow counteracting effects divergent selection, adaptations other traits buffer exposure climate extremes. limited potential plasticity observed even generalist gradients, may have resilience global warming.

Language: Английский

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Cryptic diversity in toads of the Rhinella marina species group (Anura, Bufonidae) with a subjectively beautiful new species from Western Ecuador

Zoological Journal of the Linnean Society, Journal Year: 2023, Volume and Issue: 202(3)

Published: Dec. 11, 2023

Abstract The mainly Mesoamerican cane toad, Rhinella horribilis, is the northernmost species in marina group of giant or toads, occupying an extensive range west Andean Cordillera from Ecuador north to southern Texas. However, a thorough assessment geographic variation among R. horribilis populations, and phylogenetic relationships complex, indicates previously unsuspected diversity within this as currently recognized. Specifically, we evaluated whether toad populations western represent evolutionary lineage distinct rest based on specimen collections combined evidence mtDNA sequence variation, morphological, bioacoustics, environmental information. Our results revealed that Ecuadorian Andes constitute well-supported, monophyletic clade distinctly different genetically, morphologically, acoustically, ecologically sister taxon composed Central America ascribable s.s. Amazon Basin other countries. weight confirms new (R. bellasp. nov.), described here, adding our understanding biogeographic widespread Neotropical toads. name means ‘beautiful’ Latin, contrast its species, ‘horribilis’. In addition, designate lectotype for Bufo marinus var. fluminensis avoid ambiguity applicability name.

Language: Английский

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Does a Moderately Warming Climate Compensate for the Negative Effects of UV-B Radiation on Amphibians at High Altitudes? A Test of Rana kukunoris Living on the Qinghai–Tibetan Plateau

Biology, Journal Year: 2022, Volume and Issue: 11(6), P. 838 - 838

Published: May 29, 2022

Both the warming climate and ultraviolet-B radiation (UVBR) are considered to be notable environmental factors affecting amphibian population decline, with particular effects on tadpole development. However, phenotypes of tadpoles living at high altitudes may improved by moderately temperatures, reducing or eliminating negative oxidative damage caused cool temperatures strong UVBR altitudes. To verify this hypothesis, Rana kukunoris tadpoles, which live altitudes, were used test effect interaction temperature their development antioxidant systems in a fully factorial design. The exposed UVBR-free environments 14 (cool temperature) 22 °C (warm temperature), respectively. warm had opposite influences several traits including survival, developmental rate, individual size, preferred body temperature, thermal tolerance damage, enzymatic nonenzymatic systems. moderate could compensate for override increasing tadpoles' critical thus enhancing locomotion ability sensitivity Furthermore, dark skin coloration aggregation behavior R. also effective strategies allowing them resist helping better adapt environment stronger UVBR. Thus, it is possible that degree increase capacity organisms changes have positive

Language: Английский

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