Starfish can survive thanks to adaptations like calcified skin, bright colors and the ability to regenerate limbs. Marine scientists call starfish "sea stars," although they are not really fish.
The bright shade and bony skin of starfish helps to discourage predators and protect it in case it is attacked. To eat, a starfish uses suction-cupped feet to pry open shellfish. After a shellfish is open, the starfish's stomach comes out of its mouth to consume and digest the meat.
The starfish's ability to regenerate limbs if they're lost to a predator is a huge advantage for the creature, as its slow pace can make evasion unlikely.