Strengthening of negative density dependence mediates population decline at high temperatures

Ecology, Journal Year: 2025, Volume and Issue: 106(3)

Published: March 1, 2025

Abstract While temperature is well known to affect many life history traits of ectothermic organisms, any attempt scale up these individual‐level processes population‐level consequences must assume a relationship between and the strength per capita density dependence. Yet, theory has made contrasting predictions about this relationship, we still need clear experimental tests determine which realized in natural systems, especially heterotrophs. Here, experimentally isolated quantified thermal response dependence from population dynamics herbivore Daphnia pulex . We show that negative increased linearly with temperature, doubling every 7°C, while intrinsic growth rate increase showed humped shape relationship. This difference caused humped‐shaped carrying capacity dramatic 50% decline at highest temperature. The results provide sorely needed test highlight importance accounting for responses indirect effects only emerge level when forecasting global warming. warming temperatures may benefit individual (via reproduction), our reveal can be detriment by strengthening density‐dependent processes.

Language: Английский

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A simplified approach for assessing the effects of temperature change on the stability of consumer–resource interactions

Oikos, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 10, 2025

Temperature regulates the physiology and behaviour of organisms. Thus, changing temperatures impact dynamics species interactions. Considering that consumer–resource interactions underpin ecological communities, impacts warming on stability have been extensively studied. However, a consensus among empirically determined warming–stability relationships clear understanding thereof are lacking. We investigate these systematically by developing simplified theoretical framework incorporates empirical data in three steps. define terms intrinsic oscillations to avoid comparing disparate notions, use one‐dimensional metric convert all empirically‐determined thermal dependence parametersiations into single function, directly compare data. The utilises Rosenzweig–MacArthur model with saturating consumer functional response, which has employed study warming‐stability is applied ectotherm pairs. find support for four different relationships: increases, decreases, hump‐shaped or U‐shaped increasing temperature. diversity relationships, though partly attributable context‐dependence, fundamentally caused two factors. First, relative sensitivities attack rate handling time and, second, scarcity evidence carrying capacity. former depends how processes measured, may not be consistent across studies. latter necessitates application assumptions, difficult verify, yet significant relationships. demonstrate aspects data, such as aforementioned factors range studied temperatures, can alter predicted stability. we illustrate our facilitates interactions, from producing concise overview predictions analysing causes deviation these.

Language: Английский

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Sustainable Intensification of Small-Scale Aquaculture Systems Depends on the Local Context and Characteristics of Producers

Published: Jan. 1, 2025

Language: Английский

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Temperature dependence and genetic variation in resource acquisition strategies in a model freshwater plant

Functional Ecology, Journal Year: 2024, Volume and Issue: 38(7), P. 1600 - 1610

Published: April 29, 2024

Abstract Understanding how competition varies with environmental stress is critical to anticipating species and community responses rapid change. While the stress‐gradient hypothesis predicts strength of decrease increasing stress, our understanding limited by a lack mechanistic resource‐use traits underlying competitive dynamics respond stress. Here, we use duckweeds in Lemna complex measure phenotypic genetic variation R* (a resource acquisition trait representing minimum requirement for positive population growth) high‐temperature better understand alters ability essential resources. We found that heat increased plants nitrogen acquisition. Because lower values predict dominance where resources are limiting, this indicates under stressful, high temperatures, could experience reduced due higher required sustain growth rates. minimal across 11 local genotypes within complex, indicating selection on strategies such as may be constrained nature. The expression was further suggesting response particularly Contrary predictions drawn from gleaner–opportunist trade‐off, did not find evidence trade‐off benign conditions or Plants (i.e. rates levels) were have levels, possibly because chosen diverged spp. has escaped constraint. Importantly, work increase sensitivity through an while reducing evolutionary potential traits. This study acts key step behind resource‐limited stressful environments. Read free Plain Language Summary article Journal blog.

Language: Английский

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From Skin to Gut: Understanding Microbial Diversity in Rana amurensis and R. dybowskii

Current Microbiology, Journal Year: 2024, Volume and Issue: 81(11)

Published: Sept. 13, 2024

Language: Английский

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How interactions between temperature and resources scale from populations to communities

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

Published: Sept. 23, 2024

Abstract Temperature and resources are fundamental factors that determine the ability of organisms to function survive, while influencing their development, growth, reproduction. Major bodies ecological theory have emerged, largely independently, address temperature resource effects. It remains a major challenge unite these ideas interactive effects on patterns processes, consequences across scales. Here, we propose simple, physiologically motivated model capturing (including inorganic nutrients light) growth microbial ectotherms over multiple From this derive set key predictions. At population level, predict (i) limitation thermal traits, (ii) consistent differences in sensitivity auto- heterotrophs, (iii) existence specific tradeoffs between traits shape performance curves. community predictions for (iv) how by light can change relationship productivity. All four upheld, based our analyses large compilation laboratory data as well field experiments with marine phytoplankton communities. Collectively, modeling framework provides new way thinking about interplay two aspects life — they constrain structure properties Providing links responses simultaneous changes abiotic is essential anticipating multifaceted global change.

Language: Английский

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Order matters: Autocorrelation of temperature dictates extinction risk in populations with nonlinear thermal performance

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

Published: Dec. 22, 2024

Abstract Forecasting the risks caused by climate change often relies upon combining species’ thermal performance curves with expected statistical distributions of experienced temperatures, without consideration for order in which those temperatures occur. Such averaging approaches may obscure disproportionate impacts that extreme events like heatwaves have on fitness and survival. In this study, we instead incorporate population dynamical modeling to elucidate relationship between sequence temperature – driven temporal autocorrelation extinction risk. We show permutation determines extent risk; as regimes grow warmer, more variable, autocorrelated, risk grows non-linearly is interactions among our three treatment variables. Given mean, variance, are changing nuanced ways across globe, understanding these paramount forecasting Using empirical data from a benchmarked set curves, demonstrate how impacted autocorrelation, while controlling seasonal diurnal cycling. Our results approach offer new tools testing robustness emphasize importance looking beyond temporally-blind metrics, mean size or average distributions, impending risks.

Language: Английский

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