Oceanic differences in coral-bleaching responses to marine heatwaves

The Science of The Total Environment, Journal Year: 2023, Volume and Issue: 871, P. 162113 - 162113

Published: Feb. 9, 2023

Anomalously high ocean temperatures have increased in frequency, intensity, and duration over the last several decades because of greenhouse gas emissions that cause global warming marine heatwaves. Reef-building corals are sensitive to such temperature anomalies commonly lead coral bleaching, mortality, changes community structure. Yet, despite these overarching effects, there geographical differences thermal regimes, evolutionary histories, past disturbances may different bleaching responses within among oceans. Here we examined overall Atlantic, Indian, Pacific Oceans, using both a spatially explicit Bayesian mixed-effects model deep-learning neural-network model. We used 40-year dataset encompassing 23,288 coral-reef surveys at 11,058 sites 88 countries, from 1980 2020. Focusing on ocean-wide assessed relationships between percentage bleached temperature-related metrics alongside suite environmental variables. found while sea-surface were consistently, strongly, related all oceans, clear most For instance, was an increase with depth Atlantic Ocean whereas opposite observed Indian Ocean, no trend could be seen Ocean. The standard deviation thermal-stress negatively but not Globally, has progressively occurred higher four although, again, three Together, patterns highlight historical circumstances oceanographic conditions play central role contemporary coral-bleaching responses.

Language: Английский

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Rapid diversification of grey mangroves (Avicennia marina) driven by geographic isolation and extreme environmental conditions in the Arabian Peninsula

Molecular Ecology, Journal Year: 2024, Volume and Issue: 33(4)

Published: Jan. 10, 2024

Abstract Biological systems occurring in ecologically heterogeneous and spatially discontinuous habitats provide an ideal opportunity to investigate the relative roles of neutral selective factors driving lineage diversification. The grey mangroves ( Avicennia marina ) Arabia occur at northern edge species' range are subject variable, often extreme, environmental conditions, as well historic large fluctuations habitat availability connectivity resulting from Quaternary glacial cycles. Here, we analyse fully sequenced genomes sampled 19 locations across Red Sea, Arabian Sea Persian/Arabian Gulf (PAG) reconstruct evolutionary history species region identify adaptive mechanisms Population structure phylogenetic analyses revealed marked genetic correlating with geographic distance highly supported clades among within seas surrounding Peninsula. Demographic modelling showed times divergence consistent recent periods isolation low marine during glaciations, suggesting presence (cryptic) refugia PAG. Significant migration was detected PAG, Strait Hormuz gene flow upon secondary contact populations. Genetic‐environment association high levels signs multi‐loci local adaptation driven by temperature extremes hypersalinity. These results support a process rapid diversification combined effects historical ecological selection reveal mangrove peripheral environments relevant drivers diversity.

Language: Английский

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Finding genes and pathways that underlie coral adaptation

Trends in Genetics, Journal Year: 2024, Volume and Issue: 40(3), P. 213 - 227

Published: Feb. 6, 2024

Language: Английский

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The role and risks of selective adaptation in extreme coral habitats

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: July 28, 2023

Abstract The alarming rate of climate change demands new management strategies to protect coral reefs. Environments such as mangrove lagoons, characterized by extreme variations in multiple abiotic factors, are viewed potential sources stress-tolerant corals for assisted evolution and propagation. However, biological trade-offs adaptation extremes poorly known. Here, we investigate the reef-building Porites lutea thriving both reef sites show that stress-tolerance comes with compromises genetic energetic mechanisms skeletal characteristics. We observe reduced diversity gene expression variability corals, a disadvantage under future harsher selective pressure. find density, thickness higher porosity skeletons from mangroves, symptoms metabolic energy redirection stress response functions. These findings demonstrate need caution when utilizing human interventions, current survival may compromise competitive fitness.

Language: Английский

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Coral Reef Population Genomics in an Age of Global Change

Annual Review of Genetics, Journal Year: 2023, Volume and Issue: 57(1), P. 87 - 115

Published: June 29, 2023

Coral reefs are both exceptionally biodiverse and threatened by climate change other human activities. Here, we review population genomic processes in coral reef taxa their importance for understanding responses to global change. Many on characterized weak genetic drift, extensive gene flow, strong selection from complex biotic abiotic environments, which together present a fascinating test of microevolutionary theory. Selection, hybridization have played will continue play an important role the adaptation or extinction face rapid environmental change, but research remains limited compared urgent needs. Critical areas future investigation include evolutionary potential mechanisms local adaptation, developing historical baselines, building greater capacity countries where most diversity is concentrated.

Language: Английский

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Heatwave resilience of juvenile white sturgeon is associated with epigenetic and transcriptional alterations

Scientific Reports, Journal Year: 2023, Volume and Issue: 13(1)

Published: Sept. 18, 2023

Abstract Heatwaves are increasing in frequency and severity, posing a significant threat to organisms globally. In aquatic environments heatwaves often associated with low environmental oxygen, which is deadly combination for fish. However, surprisingly little known about the capacity of fishes withstand these interacting stressors. This issue particularly critical species extreme conservation concern such as sturgeon. We assessed tolerance juvenile white sturgeon from an endangered population heatwave exposure investigated how this affects additional acute measured whole-animal thermal hypoxic performance underlying epigenetic transcriptional mechanisms. Sturgeon exposed simulated had increased exhibited complete compensation effects hypoxia. These changes were increase mRNA levels involved stress ( hsp90a, hsp90b, hsp70 hif1a ) following Global DNA methylation was sensitive rapidly responded hypoxia over course hour. data demonstrate that exhibit substantial resilience heatwaves, improved cross-tolerance stressors involving rapid responses both

Language: Английский

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Impacts of ocean warming on fish size reductions on the world’s hottest coral reefs

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: July 1, 2024

Abstract The impact of ocean warming on fish and fisheries is vigorously debated. Leading theories project limited adaptive capacity tropical fishes 14-39% size reductions by 2050 due to mass-scaling limitations oxygen supply in larger individuals. Using the world’s hottest coral reefs Persian/Arabian Gulf as a natural laboratory for - where species have survived >35.0 °C summer temperatures over 6000 years are 14-40% smaller at maximum compared cooler locations we identified two pathways that enhance survival elevated across 10 metabolic swimming performance metrics. Comparing Lutjanus ehrenbergii Scolopsis ghanam from both inside outside 27.0 °C, 31.5 35.5 reveal these show lower-than-expected rise basal demands right-shifted thermal window, which aids maintaining aerobic °C. Importantly, our findings challenge traditional oxygen-limitation theories, suggesting mismatch energy acquisition demand primary driver reductions. Our data support modified resource-acquisition theory explain how leads species-specific why individuals evolutionarily favored under temperatures.

Language: Английский

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Evolutionary Responses of a Reef-building Coral to Climate Change at the End of the Last Glacial Maximum

Molecular Biology and Evolution, Journal Year: 2022, Volume and Issue: 39(10)

Published: Oct. 1, 2022

Abstract Climate change threatens the survival of coral reefs on a global scale, primarily through mass bleaching and mortality as result marine heatwaves. While these short-term effects are clear, predicting fate over coming century is major challenge. One way to understand longer-term effect rapid climate examine response populations past shifts. Coastal shallow-water ecosystems such have been reshaped many times by sea-level changes during Pleistocene, yet few studies directly linked this with its consequences population demographics, dispersal, adaptation. Here we use powerful analytical techniques, afforded haplotype-phased whole-genomes, establish links for reef-building coral, Acropora digitifera. We show that three genetically distinct present in northwestern Australia, their divergence since last glacial maximum (LGM) can be explained combination founder-effects restricted gene flow. Signatures selective sweeps, too strong demographic history, all overlap genes different patterns functional enrichment between inshore offshore habitats. In contrast host, find photosymbiont communities largely undifferentiated corals from locations, spanning almost 1000 km, indicating selection host genes, not acquisition novel symbionts, has primary driver adaptation species Australia.

Language: Английский

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Slight thermal stress exerts genetic diversity selection at coral (Acropora digitifera) larval stages

BMC Genomics, Journal Year: 2025, Volume and Issue: 26(1)

Published: Jan. 14, 2025

Abstract Background Rising seawater temperatures increasingly threaten coral reefs. The ability of larvae to withstand heat is crucial for maintaining reef ecosystems. Although several studies have investigated larvae’s genetic responses thermal stress, most relied on pooled sample sequencing, which provides population-level insights but may mask individual genotype variability. This study uses larval sequencing investigate genotype-specific stress and the selective pressures shaping their genomes, offering finer resolution deeper insights. Results investigates response before acquiring symbiotic algae, aiming elucidate relationship between diversity stress. Larvae sourced from eight Acropora digitifera colonies were subjected ambient temperature (28 °C) conditions (31 °C). impact was assessed through sequencing. While overall diversity, represented by π, did not significantly differ control heat-exposed groups, Tajima’s D differed, indicating different in each group. genomic regions under higher lower broadly shared among head conditions, implying that operated distinctive manners. Many protein-coding sequences identified this region, codon evolution many these genes showed signs positive selection. These results highlight complex temperatures. showing selection also been influenced historical fluctuations, as suggested association with loci during Acroporid speciation. codon-level speciation potential role adaptation environmental changes over evolutionary timescales. Conclusion findings underscore significance reproduction They indicate even minor can exert significant pressure, potentially leading profound implications research understanding rising

Language: Английский

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Rapid Evolution in Action: Environmental Filtering Supports Coral Adaptation to a Hot, Acidic, and Deoxygenated Extreme Habitat

Global Change Biology, Journal Year: 2025, Volume and Issue: 31(3)

Published: March 1, 2025

The semienclosed Bouraké lagoon in New Caledonia is a natural system that enables observation of evolution action with respect to stress tolerance marine organisms, topic directly relevant understanding the consequences global climate change. Corals inhabiting endure extreme conditions elevated temperature (> 33°C), acidification (7.2 pH units), and deoxygenation (2.28 mg O2 L-1), which fluctuate tide due lagoon's geomorphology. To investigate underlying bases apparent these corals, we combined whole genome resequencing coral host ITS2 metabarcoding photosymbionts from 90 Acropora tenuis colonies three localities along steep environmental gradient two nearby control reefs. Our results highlight importance flexibility associate different facilitating holobiont; but, perhaps more significantly, strong selective effects were detected at specific loci genome. Fifty-seven genes contained SNPs highly associated environment enriched functions related sphingolipid metabolism. Within genes, conserved sensor noxious stimuli TRPA1 ABCC4 transporter stood out high number environmentally selected they contained. Protein 3D structure predictions suggest single-point mutation causes rotation main regulatory domain TRPA1, may be behind this case selection through filtering. While corals provide striking example rapid adaptation conditions, overall, our need preserve current standing genetic variation populations safeguard their adaptive potential ongoing

Language: Английский

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