Temperature dynamics, not just extremes, impact heat tolerance in mussels

Intertidal mussels, forming bumpy layers on shoreline rocks, withstand significant temperature swings as the tide ebbs and flows.

These creatures live in one of the most thermally variable environments on Earth, but a new study shows that the rate, timing, and duration of heating and cooling impact their metabolic rate, a proxy for overall health.

At the UW's Friday Harbor Laboratories, researchers exposed mussels to temperature regimens with equal highs and lows but different patterns of change. Even when the average temperature for a set period was the same, the mussels' response was distinct.

These results, published in Proceedings of the Royal Society B, show that predicting how marine organisms respond to climate change means considering how temperature changes over time, not just how warm it gets.

More information:
Michael T. Nishizaki et al, Thermal variability: how realistic temperature fluctuations alter physiological performance in intertidal mussels, Philosophical Transactions B (2026). DOI: 10.1098/rstb.2025.0261

Provided by University of Washington