7 Starfish Facts That Will Leave You Creeped Out or Cracking Up

Starfish may seem uninteresting, but they have a few surprising secrets up their sleeves! We'll share some quirky starfish facts that will creep you out or crack you up!

Starfish are marine creatures that live in the sea; they come in a range of colors, sizes, and shapes and get their name from the unique star shape formed by their legs. Starfish can only survive in saltwater, and they breathe by diffusing oxygen in the ocean over the surface of their body.

That’s why it’s essential that they are not removed from the water — in fact, they can only survive between three and five minutes outside of water, depending on the species. So, if you happen to see one washed up on the shore, carefully place it back in the sea (don’t throw it) — this is the only case where it’s OK to pick up a starfish.

So, starfish can’t survive on land; that’s one interesting fact about them. But there’s a lot more to learn about these interesting creatures. Let’s take a look at seven starfish facts that will leave you creeped out or cracking up!

Starfish Fact #1: They Can Regrow Limbs

One funky fact about starfish is that they can regrow their limbs if they are attacked by a predator. A recent study found that starfish can regenerate neurons in their body which helps to regenerate their nervous system — in fact, not only can they regrow limbs, but if they lose most of their body, some species can regrow a whole new body from just a single limb!

This is pretty cool as there are not many animals in the world that can do this, although it can take around a year for a starfish to regenerate completely. 

Starfish Fact #2: Some Starfish Have More Than Five Arms

Starfish get their name from their five-limbed star shape, but some species have between ten and fifty limbs! For example, the Antarctic sun starfish starts off with five limbs, but it can grow up to fifty. They measure about 23 inches across and can be found at ocean depths of 1,800 feet, due to this they have the nickname of coldwater starfish.

Starfish Fact #3: Starfish Turn Themselves Inside Out to Eat

Gross fact — starfish’s stomachs leave their mouth to digest the food! Yuk! They feed on shells, clams and mussels, using suction cups on their limbs to grab them.

Their mouth is located in the center of their body, the stomach comes out of the mouth to eat. The stomach then goes back inside the body when they’ve finished eating — freaky! 

Starfish Fact #4: Starfish Don't Have a Brain or Any Blood

Starfish have a complex nervous system in the ring around their mouth where they receive nutrients from filtered sea water, so they don’t have any blood or even a brain. 

Starfish Fact #5: Starfish Are Not Fish

To call starfish by their correct name, we should be saying sea star. They are not fish, as they don’t have scales, fins or gills and are more closely related to sea urchins. There are approximately 2,000 species of sea stars in the ocean, possibly more as the ocean is so vast, many areas are still undiscovered.

Starfish Fact #6. Starfish Have Eyes

These cool creatures don’t have a face, but they do have eyes! Starfish have an eye spot at the end of each limb, they look like a red spot. However, their eyesight is not very good and they can simply sense light and dark, which is enough for the ocean environments that they live in.

Even in the deepest parts of the ocean that starfish live in, it’s not completely dark — some starfish have been found to produce light in the deep seas off Greenland. It is believed this is not only to see but also to communicate with mates.

Starfish Fact #7: Some Starfish Can "Walk"

Thought starfish spend all day lying down in the sand? Well, here’s a fun starfish fact, some can bounce! In 2012, beachgoers in North Carolina spotted a starfish “walking” back to the ocean. In the above video, you can see hundreds of tiny “feet” on its limbs, which it uses to “walk” with, using a kind of hydraulic pumping action.

Note that the person who made this video carefully placed this sea star back in the ocean after filming, as previously mentioned, starfish can’t survive long outside of the water.

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Tags: Animals Guide Listicles Ocean Species Protection