Thermal Stress Responses in Intertidal Organisms

Intertidal organisms inhabit one of the most thermally dynamic environments on Earth, experiencing rapid swings between aerial exposure under direct solar radiation and immersion in cooler seawater. To withstand these extremes, they deploy behavioural strategies such as microhabitat selection and gaping, modulate metabolic rates to conserve energy, and induce molecular chaperones like heat-shock proteins to maintain protein homeostasis. At a population level, phenotypic plasticity and cryptic genetic variation shape species’ upper and lower thermal limits, enabling both short-term acclimation and long-term evolutionary adaptation. Gene regulatory networks respond to cumulative heat events by altering expression profiles, while community interactions can create microrefugia that buffer peak temperatures. Understanding these interconnected mechanisms is essential for predicting species resilience under climate change, guiding conservation of intertidal biodiversity, and managing commercially important mussel and oyster beds in a warming world.

Research from Nature Portfolio

Recent studies have employed a genome-wide association approach in a common black mussel to uncover how a silent mutation in a ubiquitin-specific protease modulates heat tolerance. Mussels carrying different alleles at this locus exhibit distinct upper thermal limits and variable expression of the gene under sublethal heat stress, particularly in sun-exposed microhabitats. This work highlights the ecological significance of cryptic genetic variation in buffering populations against temperature extremes and demonstrates the power of integrative genomic and ecological field studies to predict organismal responses to climatic warming.

Thermal Stress Responses in Intertidal Organisms publication trend

The graph below shows the total number of articles in thermal stress responses in intertidal organisms across all publications each year (not limited to Nature Index journals).

Technical terms

Upper thermal limit: The highest ambient temperature at which an organism can maintain function before experiencing lethal damage.

Heat-shock proteins (HSPs): Molecular chaperones produced in response to stress that assist in protein folding and protection against thermal damage.

Phenotypic plasticity: The ability of an organism to alter its physiology or behaviour in response to environmental variation.

Acclimation: Physiological adjustments occurring over days to weeks that enhance tolerance to new environmental conditions.

Microhabitat: Localised environmental conditions experienced by organisms within a broader habitat that can buffer or amplify climatic stress.

Synonymous mutation: A genetic change in DNA that does not alter the encoded amino acid sequence but may influence gene expression.

References

1. Genome-wide sequencing identifies a thermal-tolerance related synonymous mutation in the mussel, Mytilisepta virgata. Communications Biology (2023).
2. Linking biogeography to physiology: Evolutionary and acclimatory adjustments of thermal limits. Frontiers in Zoology (2005).
3. Non-reversible and Reversible Heat Tolerance Plasticity in Tropical Intertidal Animals: Responding to Habitat Temperature Heterogeneity. Frontiers in Physiology (2019).
4. Ocean acidification increases the sensitivity of and variability in physiological responses of an intertidal limpet to thermal stress. Biogeosciences (2018).