Climate Warming, Resource Availability, and the Metabolic Meltdown of Ectotherms

The American Naturalist, Journal Year: 2019, Volume and Issue: 194(6), P. E140 - E150

Published: July 30, 2019

Climate warming may lower environmental resource levels, growth, and fitness of many ectotherms. In a classic experiment, Brett colleagues documented that growth rates salmon depended strikingly on both temperature food levels. Here we develop simple bioenergetic model explores how fixed temperatures jointly alter the thermal sensitivity net energy gain. The incorporates differing sensitivities intake metabolism. qualitative agreement with Brett's results, it predicts decreased reduces rates, lowers optimal for highest sustaining (upper limit). Consequently, ectotherms facing reduced in warm environments should restrict activity to times when low body are biophysically feasible, but—in world—that will force shorten thus further reduce intake. This "metabolic meltdown" is consequence declining coupled accelerating metabolic costs at high warming-imposed restrictions activity. Next, extend explore increasing mean growth: reduced, upper limits lowered. We discuss our model's key assumptions caveats as well its relationship recent phytoplankton. Both models illustrate deleterious impacts climate be amplified if also either because standing resources or restricts foraging time.

Language: Английский

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Warming can destabilize predator–prey interactions by shifting the functional response from Type III to Type II

Journal of Animal Ecology, Journal Year: 2019, Volume and Issue: 88(10), P. 1575 - 1586

Published: July 1, 2019

Abstract The potential for climate change and temperature shifts to affect community stability remains relatively unknown. One mechanism by which may is altering trophic interactions. functional response quantifies the per capita resource consumption consumer as a function of abundance suitable framework description nonlinear We studied effect on ciliate predator–prey pair ( Spathidium sp. Dexiostoma campylum ) estimating warming effects associated conversion efficiency predator. recorded prey predator dynamics over 24 hr at three levels (15, 20 25°C). To these data, we fitted population dynamic model including response, such that parameters (space clearance rate, handling time density dependence space rate) were estimated each separately. evaluate ecological significance parameters, simulated dynamics. considered system be destabilized, if was driven extinct Effects increased included transition from Type III II an increase showed destabilization with warming, greater risk extinction higher temperatures likely caused response. Warming‐induced are not commonly in modelling studies investigate how respond warming. Future should generality observed simulate complex food webs type well consider possibility temperature‐dependent efficiency.

Language: Английский

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Size‐based ecological interactions drive food web responses to climate warming

Ecology Letters, Journal Year: 2019, Volume and Issue: 22(5), P. 778 - 786

Published: Feb. 28, 2019

Predicting climate change impacts on animal communities requires knowledge of how physiological effects are mediated by ecological interactions. Food-dependent growth and within-species size variation depend temperature affect community dynamics through feedbacks between individual performance population structure. Still, we know little about warming affects these feedbacks. Using a dynamic stage-structured biomass model with food-, size- temperature-dependent life history processes, analyse coexistence, stability structure in tri-trophic food chain, find that Predator densities generally decline - gradually or collapses depending which consumer stage predators feed on. Collapses occur when induces alternative stable states via Allee effects. This suggests predator persistence warmer climates may be lower than previously acknowledged web largely species

Language: Английский

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A general theory for temperature dependence in biology

Proceedings of the National Academy of Sciences, Journal Year: 2022, Volume and Issue: 119(30)

Published: July 18, 2022

At present, there is no simple, first principles–based, and general model for quantitatively describing the full range of observed biological temperature responses. Here we derive a theory dependence in biology based on Eyring–Evans–Polanyi’s chemical reaction rates. Assuming only that conformational entropy molecules changes with temperature, enzyme rates which takes form an exponential function modified by power law describes characteristic asymmetric curved response. Based few additional principles, our can be used to predict response above level, thus spanning quantum classical scales. Our provides analytical description shape curves demonstrates its generality showing convergence all responses onto universal relationships—a data collapse—under appropriate normalization identifying optimal around 25 ∘ C, characterizing curves. The good fit empirical wide variety rates, times, steady-state quantities, from molecular ecological scales across multiple taxonomic groups (from viruses mammals). This simple framework understand impact quantities principles thermodynamics, bridging

Language: Английский

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Temperature impacts on fish physiology and resource abundance lead to faster growth but smaller fish sizes and yields under warming

Global Change Biology, Journal Year: 2022, Volume and Issue: 28(21), P. 6239 - 6253

Published: July 13, 2022

Resolving the combined effect of climate warming and exploitation in a food web context is key for predicting future biomass production, size-structure potential yields marine fishes. Previous studies based on mechanistic size-based models have found that bottom-up processes are important drivers fisheries yield changing climates. However, we know less about joint effects 'bottom-up' physiological temperature; how do temperature propagate from individual-level physiology through webs alter exploited species community? Here, assess species-resolved affected by both these pathways exploitation. We parameterize dynamic size spectrum model inspired offshore Baltic Sea web, investigate individual growth rates, size-structure, relative abundances warming. The magnitude projections regional coupled system RCA4-NEMO RCP 8.5 emission scenario, evaluate different scenarios dependence fish resource productivity. When accounting temperature-effects addition to basal productivity, projected size-at-age 2050 increases average all species, mainly young fish, compared without In contrast, decreases when affects dynamics only, decline largest fish. Faster rates due warming, however, not always translate larger yields, as lower carrying capacities with increasing tend result abundance hence spawning stock biomass. These results suggest understand global structure communities, direct metabolic indirect via resources must be accounted for.

Language: Английский

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Individual variation and interactions explain food web responses to global warming

Philosophical Transactions of the Royal Society B Biological Sciences, Journal Year: 2020, Volume and Issue: 375(1814), P. 20190449 - 20190449

Published: Nov. 2, 2020

Understanding food web responses to global warming, and their consequences for conservation management, requires knowledge on how vary both among within species. Warming can reduce species richness biomass production. However, warming observed at different levels of biological organization may seem contradictory. For example, higher temperatures commonly lead faster individual body growth but decrease production fishes. Here we show that the key resolve this contradiction is intraspecific variation, because (i) community dynamics emerge from interactions individuals, (ii) ecological interactions, physiological processes effects often over life history. By combining insights temperature-dependent dynamic models simple webs, observations large temperature gradients findings short-term mesocosm multi-decadal whole-ecosystem experiments, mechanisms by which waters affect webs via individual-level review empirical support. We identify a need experiments manipulating population size structures test these mechanisms. stress within-species variation in size, are accurate predictions appropriate efforts fish function under climate. This article part theme issue 'Integrative research perspectives marine conservation'.

Language: Английский

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An Empiricist’s Guide to Using Ecological Theory

The American Naturalist, Journal Year: 2021, Volume and Issue: 199(1), P. 1 - 20

Published: Sept. 15, 2021

AbstractA scientific understanding of the biological world arises when ideas about how nature works are formalized, tested, refined, and then tested again. Although benefits feedback between theoretical empirical research widely acknowledged by ecologists, this link is still not as strong it could be in ecological research. This part because theory, particularly expressed mathematically, can feel inaccessible to empiricists who may have little formal training advanced math. To address persistent barrier, we provide a general accessible guide that covers basic, step-by-step process approach, understand, use theory work. We first give an overview why mathematical created, outline four specific ways both verbal motivate work, finally present practical tool kit for reading aspects theory. hope empowering embrace their work will help move field closer full integration

Language: Английский

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Linking species traits and demography to explain complex temperature responses across levels of organization

Proceedings of the National Academy of Sciences, Journal Year: 2021, Volume and Issue: 118(42)

Published: Oct. 12, 2021

Significance Microbes regulate nutrient flux and carbon storage within ecosystems, making them essential to the global cycle ecosystem responses climate change. Understanding how change will alter microbial communities this feed back influence pace of requires linking processes across levels organization, from individual organisms whole ecosystems. We show that physical characteristics (traits) protist species their populations respond changes in temperature. These species-level temperature also composition, dynamics, functioning communities. Using traits understand complex, multilevel with can help us anticipate possible consequences rapid

Language: Английский

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Long-term experimental evolution decouples size and production costs in Escherichia coli

Proceedings of the National Academy of Sciences, Journal Year: 2022, Volume and Issue: 119(21)

Published: May 20, 2022

Significance Populations of larger organisms should be more efficient in their resource use, but grow slowly, than populations smaller organisms. The relations between size, metabolism, and demography form the bedrock metabolic theory, most empirical tests have been correlative indirect. Experimental lineages Escherichia coli that evolved to make cells provide a unique opportunity test how covary. Despite having relatively slower they faster cells. They achieve this growth rate advantage by reducing relative costs producing That evolution can decouple production from size challenges fundamental assumption about connections physiology ecology.

Language: Английский

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Eco‐evolution from deep time to contemporary dynamics: The role of timescales and rate modulators

Ecology Letters, Journal Year: 2023, Volume and Issue: 26(S1)

Published: Sept. 1, 2023

Eco-evolutionary dynamics, or eco-evolution for short, are often thought to involve rapid demography (ecology) and equally heritable phenotypic changes (evolution) leading novel, emergent system behaviours. We argue that this focus on contemporary dynamics is too narrow: Eco-evolution should be extended, first, beyond pure include all environmental dimensions and, second, slow which unfolds over thousands millions of years. This extension allows us conceptualise biological systems as occupying a two-dimensional time space along axes capture the speed ecology evolution. Using Hutchinson's analogy: Time 'theatre' in evolution two interacting 'players'. therefore dynamic: identify modulators ecological evolutionary rates, like temperature sensitivity mutation, can change evolution, hence impact eco-evolution. Environmental may synchronise via these rate modulators, increasing occurrence represents substantial challenges prediction, especially context global change. Our perspective attempts integrate across disciplines, from gene-regulatory networks geomorphology timescales, today deep time.

Language: Английский

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