Corals adapted to extreme and fluctuating seawater pH increase calcification rates and have unique symbiont communities

Ecology and Evolution, Journal Year: 2023, Volume and Issue: 13(5)

Published: May 1, 2023

Ocean acidification (OA) is a severe threat to coral reefs mainly by reducing their calcification rate. Identifying the resilience factors of corals decreasing seawater pH paramount importance predict survivability in future. This study compared adapted variable pHT (i.e., 7.23-8.06) from semi-enclosed lagoon Bouraké, New Caledonia, more stable 7.90-8.18). In 100-day aquarium experiment, we examined physiological response and genetic diversity Symbiodiniaceae three species (Acropora tenuis, Montipora digitata, Porites sp.) both sites under pHNBS conditions (8.11, 7.76, 7.54) one fluctuating regime (between 7.56 8.07). Bouraké consistently exhibited higher growth rates than environment. Interestingly, A. tenuis showed highest rate 7.76 condition, whereas for M. sp. was 8.11 conditions, respectively. While OA generally decreased ca. 16%, environment (21% increase 93% with all pooled). superior performance coincided divergent symbiont communities that were homogenous corals. Corals appear have better capacity calcify reduced native condition. not gained exposed during suggesting long-term exposure fluctuations and/or differences benefit OA.

Language: Английский

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Delineating the emergence of thermally tolerant Symbiodiniaceae genotypes across the dominant coral species of a turbid reef: Adaptation and resilience strategy

The Science of The Total Environment, Journal Year: 2025, Volume and Issue: 963, P. 178255 - 178255

Published: Jan. 17, 2025

Language: Английский

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High physiological function for corals with thermally tolerant, host-adapted symbionts

Proceedings of the Royal Society B Biological Sciences, Journal Year: 2023, Volume and Issue: 290(2003)

Published: July 19, 2023

The flexibility to associate with more than one symbiont may considerably expand a host's niche breadth. Coral animals and dinoflagellate micro-algae represent of the most functionally integrated widespread mutualisms between two eukaryotic partners. Symbiont identity greatly affects coral's ability cope extremes in temperature light. Over its broad distribution across Eastern Pacific, ecologically dominant branching coral, Pocillopora grandis , depends on dinoflagellates Durusdinium glynnii Cladocopium latusorum . Measurements skeletal growth, calcification rates, total mass increase, calyx dimensions, reproductive output response thermal stress were used assess functional performance these partner combinations. results show both host–symbiont combinations displayed similar phenotypes; however, significant differences emerged when exposed increased temperatures. Negligible physiological colonies hosting thermally tolerant D. refute prevailing view that have considerable growth tradeoffs. Well beyond pocilloporid are found Pacific warm, environmentally variable, near shore lagoonal habitats. While rising ocean temperatures threaten persistence contemporary coral reefs, lessons from indicate co-evolved likely spread geographically dominate reef ecosystems future.

Language: Английский

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Divergent bleaching and recovery trajectories in reef-building corals following a decade of successive marine heatwaves

Proceedings of the National Academy of Sciences, Journal Year: 2023, Volume and Issue: 120(52)

Published: Dec. 19, 2023

Increasingly frequent marine heatwaves are devastating coral reefs. Corals that survive these extreme events must rapidly recover if they to withstand subsequent events, and long-term survival in the face of rising ocean temperatures may hinge on recovery capacity acclimatory gains heat tolerance over an individual’s lifespan. To better understand trajectories successive heatwaves, we monitored responses bleaching-susceptible bleaching-resistant individuals two dominant species Hawai’i, Montipora capitata Porites compressa , a decade included three heatwaves. Bleaching-susceptible colonies P. exhibited beneficial acclimatization stress (i.e., less bleaching) following repeat becoming indistinguishable from conspecifics during third heatwave. In contrast, M. repeatedly bleached all seasonal bleaching substantial mortality for up 3 y Encouragingly, both remained pigmented across entire time series; however, pigmentation did not necessarily indicate physiological resilience. Specifically, displayed incremental yet only partial symbiont density tissue biomass phenotypes 35 mo heatwave as well considerable mortality. Conversely, appeared most metrics within 2 experienced little no Ultimately, results even some visually robust, corals can carry cost recurring multiple years, leading divergent erode reef resilience Anthropocene.

Language: Английский

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Heat‐evolved algal symbionts enhance bleaching tolerance of adult corals without trade‐off against growth

Global Change Biology, Journal Year: 2023, Volume and Issue: 29(24), P. 6945 - 6968

Published: Nov. 1, 2023

Ocean warming has caused coral mass bleaching and mortality worldwide the persistence of symbiotic reef-building corals requires rapid acclimation or adaptation. Experimental evolution coral's microalgal symbionts followed by their introduction into is one potential method to enhance thermotolerance. Heat-evolved generalist species, Cladocopium proliferum (strain SS8), were exposed elevated temperature (31°C) for ~10 years, introduced four genotypes chemically bleached adult fragments scleractinian coral, Galaxea fascicularis. Two acquired SS8. The new persisted 5 months experiment enhanced thermotolerance, compared with that inoculated wild-type C. strain. Thermotolerance SS8-corals was similar from same colony hosting homologous symbiont, Durusdinium sp., which naturally heat tolerant. However, SS8-coral exhibited faster growth recovered cell density photochemical efficiency more quickly following chemical inoculation under ambient relative Durusdinium-corals. Mass spectrometry imaging suggests algal pigments involved in photobiology oxidative stress greatest contributors thermotolerance differences between heat-evolved versus proliferum. These may have increased photoprotection symbionts. This first laboratory study show (G. fascicularis) can be via uptake exogenously supplied, symbionts, without a trade-off against temperature. Importantly, remained moderate abundance 2 years after inoculation, suggesting long-term stability this novel symbiosis benefits

Language: Английский

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Coral larvae increase nitrogen assimilation to stabilize algal symbiosis and combat bleaching under increased temperature

PLoS Biology, Journal Year: 2024, Volume and Issue: 22(11), P. e3002875 - e3002875

Published: Nov. 12, 2024

Rising sea surface temperatures are increasingly causing breakdown in the nutritional relationship between corals and algal endosymbionts (Symbiodiniaceae), threatening basis of coral reef ecosystems highlighting critical role reproduction maintenance. The effects thermal stress on metabolic exchange (i.e., transfer fixed carbon photosynthates from symbiont to host) during sensitive early life stages, however, remains understudied. We exposed symbiotic Montipora capitata larvae Hawaiʻi high temperature (+2.5°C for 3 days), assessed rates photosynthesis respiration, used stable isotope tracing (4 mM 13 C sodium bicarbonate; 4.5 h) quantify metabolite exchange. While did not show any signs bleaching experience declines survival settlement, depression was significant under temperature, indicated by a 19% reduction respiration rates, but with no change photosynthesis. Larvae showed evidence maintained translocation major photosynthate, glucose, symbiont, there reduced metabolism glucose through central glycolysis). larval host invested nitrogen cycling increasing ammonium assimilation, urea metabolism, sequestration into dipeptides, mechanism that may support maintenance stress. Host assimilation via dipeptide synthesis appears be limitation Symbiodiniaceae, we hypothesize contributes retention favoring photosynthate host. Collectively, our findings indicate although these susceptible diverting energy maintain population density, photosynthesis, allow avoid highlights potential stage specific responses

Language: Английский

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An abundant mutualist can protect corals from multiple stressors

Proceedings of the Royal Society B Biological Sciences, Journal Year: 2025, Volume and Issue: 292(2040)

Published: Feb. 1, 2025

Mutualisms can increase the ability of foundation species to resist individual stressors, but it remains unclear whether mutualisms also ameliorate co-occurring stressors for habitat-forming species. To examine a suspected mutualist could improve species’ resistance multiple we tested how common coral-dwelling crab affected corals exposed macroalgal contact and physical wounding during widespread heat stress event using flow-through tanks supplied with seawater from nearby reef flat. High temperatures on flat, which raised temperature in our tanks, appeared trigger rapid tissue loss experimental corals, amount lost by was strongly determined treatment. Macroalgal increased, while presence decreased, lost. Although effect not strong isolation, when occurred crab, coral unexpectedly decreased below that all other treatments. We propose increased attracting crabs—a result supported field experiment. These results highlight interact unexpected ways, buffering effects both local global

Language: Английский

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Mutualism breakdown underpins evolutionary rescue in an obligate cross-feeding bacterial consortium

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: April 11, 2025

Abstract Populations facing lethal environmental change can escape extinction through rapid genetic adaptation, a process known as evolutionary rescue. Despite extensive study, rescue is largely unexplored in mutualistic communities, where it likely constrained by the less adaptable partner. Here, we explored empirically likelihood, population dynamics, and mechanisms underpinning an obligate mutualism involving cross-feeding of amino acids between auxotrophic Escherichia coli strains. We found that over 80% populations overcame severe decline when exposed to two distinct types abrupt, stress. Of note, all cases only one strains survived metabolically bypassing auxotrophy. Crucially, consortium exhibited greater sensitivity both stressors than prototrophic control strain, such reversion autonomy was sufficient alleviate stress below levels. This common across other stresses, suggesting may be general feature acid–dependent mutualisms. Our results reveal depend critically on specific physiological details interacting partners, adding rich layers complexity endeavor predicting fate microbial communities intense deterioration.

Language: Английский

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Leveraging Functional Genomics and Engineering Approaches to Uncover the Molecular Mechanisms of Cnidarian–Dinoflagellate Symbiosis and Broaden Biotechnological Applications

Phycology, Journal Year: 2025, Volume and Issue: 5(2), P. 14 - 14

Published: April 26, 2025

Functional genomics is a powerful approach for uncovering molecular mechanisms underlying complex biological processes by linking genetic changes to observable phenotypes. In the context of algal symbiosis, this framework offers significant potential advancing our understanding interactions between marine dinoflagellates and their cnidarian hosts, such as corals—organisms that are foundational ecosystems biodiversity. As coral bleaching reef degradation intensify due environmental stressors, novel strategies urgently needed enhance resilience these symbiotic partnerships. This opinion piece explores emerging directions in functional applied coral–algal with focus on pathways govern photosynthesis stress tolerance. We discuss challenges opportunities applying support health, improve ecosystem resilience, inform biotechnological applications agriculture medicine. Together, insights posit engineered symbioses mitigating biodiversity loss supporting sustainable management face accelerating change.

Language: Английский

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The role of holobiont composition and environmental history in thermotolerance of Tropical Eastern Pacific corals

Current Biology, Journal Year: 2025, Volume and Issue: unknown

Published: June 1, 2025

Language: Английский

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