How do starfish dissipate heat?

In the center of the five arms of the starfish (some species have more stellar arms), there is a central disc. Inside the central disc are the heart, stomach, and central nervous system. If the temperature of the central disc rises above 35°C (for example, during low tide when starfish may become isolated from cool seawater), the starfish will die.

The online edition of *The Journal of Experimental Biology* reported that when the temperature of the central disc reaches 35°C, about one-third of the starfish die. Researchers found that in the surviving starfish, the arms were several degrees warmer than the central disc, reaching up to 39°C, indicating that the starfish transfer heat to their arms.