Is a sea sponge an animal? Questions of the Week: Why are sea sponges considered?

There are sponges at the Flower Garden Banks National Marine Sanctuary.The colors and texture of sponges add to the complexity of the reef.Credit: G.P.Schmahl.

Sponges are often mistaken for plants and are a wide variety of colors, shapes, and sizes.Scientists think that their different colors may protect them from the sun's harmful ultraviolet rays.

Sponges have been around for a long time and have a fossil record that dates back 600 million years.The living sponges are classified into four different classes, with the most diverse being the Demospongiae, which contains 90 percent of the sponges.

sponges are completely different from corals in that they are immobile and have different reproductive processes.The main differences are.

sponges are important inhabitants of coral reefA diverse sponge population can affect the water quality on the reef.Sponge species are thought to make carbon biologically available by excreting a form of "sponge poop" that other organisms feed on.The survival of other reef organisms is aided by the protection of the reef by sponges.

It is possible for a sponge to live on hard, rocky surfaces such as sand and mud.sponges attach themselves to floating debrisRarely are they free-floating.

The sponge gets food and oxygen as it filters water through its porous exterior.Inside the sponge, tiny hairlike structures called flagella create currents to filter outbacteria and trap food within them.Sponges are impervious to high volume of water that flows through them each day.