A study published in Science(opens a new tab) in May 2026 provides new insight into how organisms with no brain or musculoskeletal system can generate and regulate this process — and what happens when the water around them warms up. Warmer water naturally carries less oxygen, which prompts corals to move their cilia faster and faster, as if gasping for breath. Above a certain temperature, the system starts to work against itself; the furious beating of cilia uses up any oxygen the coral’s tissues can absorb, and then the polyps can suffocate in the less oxygenated water. Biophysicists, marine biologists, mathematicians, and modelers are now collaborating to better understand the physiological and hydrodynamic forces at work, and how they correlate with bleaching patterns, coral disease, and mass die-offs.

link to open access paper https://www.science.org/doi/10.1126/sciadv.aeg0950

We found that the dynamics of ciliary transport are closely linked to the spatial scale of the vortices generated by the coral. As the CBF increased with temperature, the resulting vortices became larger and more vigorous, amplifying both the rate and spatial extent of local flow. This temperature-dependent scaling highlights ciliary hydrodynamics as a finely tuned mechanism capable of modulating mass transport across the coral tissue-water interface. However, the overall pattern of mass transport revealed a more complex and unexpected response to warming. In our experiments conducted under dark conditions with coral respiration consuming O2, moderate warming initially stimulated ciliary activity and enhanced advective O2 transport across the CBL. This transient increase in exchange efficiency likely extended the functional reach of coral microenvironments (30), suggesting that ciliary motion can temporarily buffer corals against mild environmental stress. This benefit, however, appears short-lived