Pink Brittle Star
Palmyra Atoll, Line Islands, Central Pacific Ocean
NOAA Vessel Hi’ialakai, shipboard studio
Archival Pigment Print
Brittle stars are highly mobile echinoderms that use their long, snake-like arms to get around. Unlike most quickly-moving animals, they have no directionality, lacking not only a head but even front and back ends. So how do these brainless creatures manage to move toward or away from anything in a directed way? Recent studies have found that when a brittle star crawls, it designates one of its five arms as the front and then “rows” with the arms on either side of that one, an action that propels it forward, that is, in the direction of the assigned “front arm.” The brittle star changes direction without rotating its body; it simply designates a new front arm.