Starfish

Starfish, also called sea stars, are amazing ocean animals. Most have five arms, but some species have up to 40! Starfish are not actually fish. They do not have brains or blood. Instead of blood, seawater pumps through their bodies.

Amazing Abilities

Starfish have an incredible superpower: they can regrow lost arms! If a starfish loses an arm, it can grow a brand new one. Some species can even grow a whole new body from just one arm. They have tiny tube feet under their arms that help them move and hold onto rocks.

A starfish with seven arms resting on the sea floor.
A starfish with seven arms resting on the sea floor. (لا روسا / Wikimedia Commons)

How They Eat

Starfish have a very unusual way of eating. They push their stomach out through their mouth and wrap it around their food, like clams and mussels. Their stomach digests the food outside their body, and then they pull it back in.

Fun Facts

  • Starfish can regrow their arms.
  • They have eyes at the tip of each arm.
  • There are about 2,000 species of starfish.

Did You Know?

Starfish do not have blood. Instead, their bodies are filled with filtered seawater that brings nutrients to their organs!