When people think of starfish they think of the typical five armed creature as pictured above and that is correct for the majority of species. But the species is very diverse and starfish can have anything up to 50 arms and come in a large variety of shapes as shown by the feather stars on a previous post. There are so many beautiful members of this family that you can see while you visit the Great Barrier Reef.
The starfish uses water to propel itself. Yes you thought that it used all those little “legs” with suction caps to move along. Well they do and they use water taken in through their body to provide suction to those “legs”. This helps the starfish to appear to float or glide across the surface of the water.
Starfish generally eat their food whole and use their stomachs to digest their food. They eat just about anything they can find on the reef including clams, fish, molluscs, small fish, coral and algae. They can also digest food outside their body by excreting their stomachs allowing them to eat creatures much largers then they could through their mouth.
Sea stars have endoskeletons. The top of the starfish is sensitive to light and the bottom of the starfish is sensitive to different chemical compositions allowing them to “smell” food. Another cool fact is the starfish breathes through it’s feet.
Starfish breed a lot depending on species. The can be hermaphrodites, capable of sexual and asexual reproduction, some are born males and later change into females. One common fact is you cannot tell the difference between the male and females unless you see them during spawning. Reproductive organs are contained within the starfish.