Mostly known as the go-to fashion choice of mermaids, Sea Stars are one of the most iconic marine animals of all time! Known previously as the Starfish, Sea Stars are surprisingly not even fish! Fish have important anatomical parts like gills, scales, and fins; Sea Stars have none of these. Sea Stars are actually invertebrates just like sand dollars and corals, which you can also see at SeaQuest Roseville,, Minnesota. Crustaceans (crabs and lobsters) are also invertebrates, but unlike crustaceans, Sea Stars do not have a shell!
WAIT, Sea Stars have no fins! So how do they MOVE?
Sea Stars don’t stay still their whole lives, they don’t use the ocean’s tides to move along the ocean floor, so then how do they move? Sea Stars typically have five “legs” that surround their body, this is what creates the radial symmetry of their shape. Underneath each one of the legs of a Sea Star sits hundreds of “feet” that allow them to walk along the floor of the ocean. Recent research has shown that these feet have a natural glue that allows Sea Stars to stick to rocks and coral so that the tides do not wash them away! Another interesting fact about the legs of a Sea Star is that they can regenerate. If a Sea Star loses a leg due to a predator, it can grow a new arm later (although this can take about a year to grow back).
We know all about the legs of a Sea Star now, but what about everything else? Sea Stars actually have no brain and no blood! They use filtered seawater to pump nutrients through their nervous system. This is also the reason that Sea Stars can’t survive in freshwater. Sea Stars also live long lives compared to most sea creatures. The average lifespan is 35 years!
One of the most interesting things about Sea Stars is how they eat! Sea Stars have two stomachs, creating a two-part eating system. The first stomach leaves the body once the Sea Star finds its prey and produces a digestive enzyme onto the prey to break down, then the second stomach then eats and digests the prey.
SeaQuest’s interactive exhibits at Roseville,, Minnesota have tanks where you can see and touch Sea Stars!