Facts about Starfish
Posted by Admin / in Science Facts
Starfish are beautiful and unique sea animals.
Starfish (Sea Star) Facts
- Starfish, also known as sea stars, are not fish. To be a fish an animal must be a vertebrate (have a backbone) Starfish are invertebrates since they have no backbone.
- Instead of having a backbone, starfish gets its shape from its exoskeleton.
- Starfish are a type of animal known as an echinoderm.
- Starfish are known for their arms that create a shape like a star. They have a thick center with 5 or more arms, also known as rays. Different species of starfish have more than 5 arms. Some starfish have as many as 50 arms!
- There are over 2000 different species of starfish that scientists have identified.
- Starfish can grab onto rocks, the ocean bottom or prey using tiny feet known as tube feet, located on the underside of their body.
- Starfish have been found in all the oceans on earth.
- Starfish only live in the sea. There are none found in freshwater although some starfish can survive being in mixed seawater and freshwater areas.
This starfish lost an arm, but now it is growing back.
Find out what starfish eat
- Starfish are predators.
- Starfish have a very unique way of capturing prey for their next meal.
- Starfish love to eat mussels, sea snails, barnacles, chitons, scallops and other sea animals.
- Starfish prey are normally stationery or slow-moving sea animals that protect themselves with a hard outer shell. These animals are usually found on the bottom of the ocean, coral, rocks and man-made structures.
- Most sea predators leave the small sea shell animals alone, but not starfish.
- Starfish can wrap around a sea animal hiding in their shell and use their tube feet to pull open the shell. Once their is an opening, starfish extend their stomach outside their body. The starfish stomach digests the body of their prey to allow them to eat.
- The starfish uses their relatively small mouth to feed on the partially digested food.
- When mussels and some other shellfish detect a starfish, they try to hop away.
Interesting starfish (sea star) facts
- Starfish can squeeze water in and out of their tube feet like tiny jets to move around or stay in one position while fighting waves and ocean tides.
- Most starfish can lose an arm from damage or to avoid being eaten by a predator. Starfish can not only survive losing an arm, but most types of starfish can grow the arm back.
- Starfish are normally born from eggs. Amazingly, scientists have discovered around 30 starfish species that are very unique. Some types of starfish can break in half to become two completely separate starfish. Some can even break off one or more of their arms, which can grow into completely new starfish.
- Starfish do not have a brain or a nervous system.