They digest prey outside of their bodies by extruding their stomach out through their mouth and enveloping their meal. Once the food is digested, their stomach is drawn back into their body. Sea stars live in salt water and are found in all of the world's oceans, from warm, tropical waters to the cold seafloor.

What do starfish eat and what eats them?

These voracious predators are always on the hunt. They feed on clams, worms, crustaceans and other small prey that can be found in the substrate. However, some species' diets are made up of algae and detritus, whereas others will only eat coral polyps (more on this later).

How does a starfish eat an oyster?

When some species of starfish find a tasty snack, such as a mussel or an oyster, they extend their stomach out of their mouth to digest the soft parts of their prey. This creates a soup-like substance that they then slurp back into their body to finish off the feast.