Starfish Trivia | 40 facts about the animal

Starfish is an iconic sea animal, that is very popular for its star – shape, which kinda gave it its name.

Let’s find out more about it!

1. Starfish is also named as a sea star.
2. Starfish is not… fish!
3. Starfish are star-shaped echinoderms.
4. They belong to the class Asteroidea.
5. Common usage frequently finds these names being also applied to ophiuroids, which are correctly referred to as brittle stars or basket stars.
6. Starfish are also known as Asteroids due to being in the class Asteroidea.
7. About 1,500 species of starfish occur on the seabed in all the world’s oceans.
8. You can find them from the tropics to frigid polar waters. T
9. hey are found from the intertidal zone down to abyssal depths, 6,000 m (20,000 ft) below the surface.
10. Starfish are marine invertebrates.
11. They typically have a central disc and usually five arms, though some species have a larger number of arms.
12. Many species are brightly coloured in various shades of red or orange, while others are blue, grey or brown.
13. Starfish have tube feet operated by a hydraulic system and a mouth at the centre of the oral or lower surface.
14. They are opportunistic feeders, and something you don’t usually expect of them is that they are mostly predators on benthic invertebrates.
15. Several species have specialized feeding behaviours including eversion of their stomachs and suspension feeding.
16. They have complex life cycles and can reproduce both sexually and asexually.
17. Most can regenerate damaged parts or lost arms and they can shed arms as a means of defense.
18. Starfish have become widely known as examples of the keystone species concept in ecology.
19. The tropical crown-of-thorns starfish (Acanthaster planci) is a voracious predator of coral throughout the Indo-Pacific region, and the northern Pacific sea star is considered to be one of the world’s 100 worst invasive species.
20. The fossil record for starfish is ancient, dating back to the Ordovician around 450 million years ago.
21. Only the ossicles and spines of the animal are likely to be preserved, making remains hard to locate.
22. With their appealing symmetrical shape, starfish have played a part in literature, legend, design and popular culture. They are sometimes collected as curios, used in design or as logos,
23. In some cultures, despite possible toxicity, they are eaten.
24. They have no brain.
25. They do have eyes though.
26. Sea stars have an eye spot at the end of each arm. This means that a five-armed sea star has five eyes, while the 40-armed sun star has 40 eyes.
27. Each sea star eye is very simple and looks like a red spot. It doesn’t see much detail but it can sense light and dark, which is just enough for the environments the animals live in.
28. Also, they have no blood. Instead of blood, sea stars have a circulatory system made up primarily of seawater.
29. Starfish use filtered sea water to pump nutrients through their nervous system.
30. They can live up to 35 years.
31. They are unable to survive in fresh water.
32. They can have up to 40 arms!
33. Sea stars have a tough covering on their upper side, which is made up of plates of calcium carbonate with tiny spines on their surface.
34. A sea star’s spines are used for protection from predators.
35. Their predators can be birds, fish, and sea otters.
36. At least for something of their small size, sea stars can weigh up to 11 pounds.
37. Starfish are equipped with hundreds of tiny little feet at the end of each arm.
38. The Cushion Starfish has a round blob-like shape, while having all the genetic qualities needed to be a starfish.
39. This starfish is actually much gentler than other starfish, feeding on detritus and plants. Other starfish will tend to feed on clams or oysters.
40. The scientific name Asteroidea was given to starfish by the French zoologist de Blainville in 1830, and it has a Greek origin.