When you want to see the stars, find someplace dark
They are everywhere in the tide zone, an extraordinarily common species. So common I usually forget to take a picture. A closer look shows a cool animal. The spines are modified, no sharp needles here, armor plates instead. An excellent arrangement for resisting the fury of the waves and still giving protection from would be predators.
A pretty urchin found in a cave. Apparently this is the rule for these urchins, found under rock and rubble when small, larger individuals found in caves or deep crevices with an active aversion to light. Most urchins move pretty slowly, the motion barely perceptible. This echinoderm was moving, tube feet furiously propelling it along the cave roof as it tried to avoid our lights.
