Keywords: nps cinms sea star seastar starfish knobby symmetry crunch biology water underwater animal coral In Channel Islands National Marine Sanctuary lies a knobby sea star. The knobs on this sea star are actually jaw-like structures that crunch on small organisms that land on them! Photo Credit: NPS In Channel Islands National Marine Sanctuary lies a knobby sea star. The knobs on this sea star are actually jaw-like structures that crunch on small organisms that land on them! Photo Credit: NPS |