Sea stars (also called starfish) are invertebrate animals belonging to the echinoderm phylum. Although the larvae are free-swimming, as adults, these are slow-moving or sedentary marine animals that exhibit radial symmetry. Cold-blooded organisms (those that cannot maintain a consistent internal body temperature) with limited locomotion have to be able to adapt to different climactic conditions. This can be especially problematic for intertidal species that spend some time each day exposed to the sun. The sea star Pisaster ochraceus has found a novel way of coping with temperature fluctuations.
This is not to suggest that sea stars can remember events or plan strategies. It would be interesting to learn whether this type of thermoregulation is common among sedentary shoreline creatures.