Sea stars eat with their stomachs inside-out.

Speaking of prey, sea stars have a rather unique way of eating theirs. A sea star's mouth is on its underside. They prey on bivalves like mussels and clams, as well as small fish, snails, and barnacles. If you've ever tried to pry the shell of a clam or mussel open, you know how difficult it is. Sea stars wrap their arms around the animal's shell and pull it open just enough. And then it does something we could never imagine - it pushes its stomach through its mouth and into the bivalve's shell. It then digests the animal and slides its stomach back into its own body. This unique feeding mechanism allows the sea star to eat larger prey than it would otherwise be able to fit into its tiny mouth.