Top 10 Starfish Facts!

Is a starfish a fish?

No of course it isn’t! But here are 10 true facts about starfish (or more scientifically named sea stars):

1 ) Sea stars are echinoderms, and are close relatives to the sea cucumber and sea urchins.

2 ) There are over 2000 species of Sea Star.

3 ) Sea stars do not always have the standard 5 arms; the sun star (a fairly redundant name) has up to 40 arms!!

4 ) A sea star can regenerate one of its arms! some sea stars drop off their arms as a distraction to predators. not the best idea but it must work to some extent.

5 ) A severed arm can grow into another sea star, as the majority of their organs are placed within the arm.

6 ) The majority of sea stars have a hard protective layer on the top of them. these is made of calcium carbonate which is a common substance found in rock. This protects them from their prey which are birds, large carnivorous fish and sea otters.

7 ) There isn’t a drop of blood within a sea star, they use a ater vascular system. they pull water in through a sieve plate. They also use this to move as they propel water to tips of their arms pushing them around.

8 ) Sea Stars digest their food on the outside of their body. This is incredible. It latches on to a clam or muscle, prises it open, slides its stomach outside its mouth and into the gap in the shell and digests what’s inside. This allows the sea star to eat a larger organism than what could fit into its mouth on its underside. Once the stomach is retracted back into its body, it transfers from the one stomach (cardiac) to another internal stomach (Pyloric) to fully digest.

9 ) Sea stars have eyes at the end of each arm, they do not have great vision but they are used.

10 ) the largest (widest diameter) discovered starfish found was erasterias echinisoma which was measured at over a meter long. thromidia catalai is the world record breaker for the heaviest weighing over 6kg