Are starfish really fish?

Although sea stars live in the ocean, they are very different from fish. They do not have gills, scales, or fins, and they survive only in saltwater environments. Instead of using blood to transport nutrients throughout their bodies, sea stars rely on seawater that moves through a special internal system called a water vascular system.

Matteo Sterling

Desk note

How Sea Stars Move

Sea stars travel across the ocean floor with the help of thousands of tiny tube feet located on the underside of their bodies. These small structures allow them to crawl, grip surfaces, and capture prey.

Some species are surprisingly fast. For example, an adult sunflower sea star can move at an impressive rate of about one meter per minute by using as many as 15,000 tube feet. These tube feet also play an important role in helping sea stars hold onto and handle their food.

Sea Stars and Their Echinoderm Relatives

Sea stars belong to the echinoderm group, along with animals such as sand dollars, sea urchins, and sea cucumbers. Echinoderms are known for their unique five-part radial symmetry, meaning their bodies are arranged around a central point.

However, not every sea star has exactly five arms. Some species have many more, with certain varieties possessing 10, 20, or even 40 arms.

Amazing Regeneration Ability

One of the most remarkable features of sea stars is their ability to regrow lost body parts. If a sea star loses one of its arms, it can regenerate a replacement over time. This incredible adaptation helps these marine animals survive injuries and continue thriving in their underwater habitats.

The best town to stay in the Cinque Terre

One look at a photograph of Cinque Terre is usually enough to make travelers dream of visiting this spectacular corner of Italy. The name Cinque Terre means “five lands” in Italian, referring to the five colorful coastal villages that make up this famous destination. Once you decide to visit, another question quickly appears: which Cinque Terre village is the best place to stay?

The 15 Most Stunning Vases You’ll Ever Lay Eyes On

Have you ever come across a flower arrangement that left you speechless, making you eager to recreate the bouquet yourself? Well, you might discover that arranging flowers is trickier than it seems. But why is that? For your flower displays to look incredible—believe it or not—you need the right vase! Don’t take our word for it? Check out our pick of the 15 most beautiful vases below and fall in love yourself… By the way, if you choose the perfect vase, you don’t need a massive bouquet. Sometimes, even 1-3 simple flower stems are enough to work their magic in the right vessel.

Artist Creates Stunning Paper Animal Sculptures

Paper, when compared to other artistic materials, is incredibly delicate. It tears under minimal pressure, disintegrates in water, and creases if folded incorrectly. Yet, its fragility belies its versatility, as shown in the work of Thiên Dinh. Through careful manipulation, Dinh transforms fragile sheets into lifelike birds, slender fish, scaly dragons, and more.

Elizabeth Tower Revealed: Fascinating Facts About Big Ben

Standing as one of London’s most recognizable landmarks, Elizabeth Tower, commonly referred to as Big Ben, is more than just a clock; it is a symbol of British heritage, endurance, and architectural achievement. Its presence on the banks of the River Thames has become synonymous with London itself, appearing in countless films, postcards, and photographs. Yet, despite its familiarity, many intriguing details about the tower and its famous bell remain lesser known. From its historical origins to its unique engineering feats, this guide explores ten fascinating aspects that make Big Ben an enduring marvel.