Sponge Facts

The word 'sponge' either reminds us of the bathroom sponge or the little yellow energetic sea sponge: 'Sponge Bob'. However, we seldom think about the wonderful sea sponge adorning the ocean floor. Living sea sponges look nothing like the dish washing sponge we keep in the kitchen, which happens to be only the skeleton of one type of sponge. Sponges appear in all sorts of glorious colors and shapes, found attached to the ocean floor. Sea sponges attach themselves permanently to solid substrates so that they do not drift around underwater.

Some Key Facts About Sponges

Animal or Plant...

• Did you know that the sea sponge is not a plant or even part of a coral reef, but is classified as an animal under the Phylum Porifera.
• Sponges were believed to be solidified sea foam in the sixteenth century and until 1765 they were thought to be plants.
• Sea sponges are classified as animals, however, lack the brain, the central nervous system, digestive system and a cardiovascular system.
• Sponges do not have organs, instead have specialized cells that carry out all essential processes.
• So if sponges lack a digestive system, how do they get their food digested and excreted? Well, sponges depend on a constant flow of water running through their bodies to obtain food (plankton and organic particles) and oxygen and also to discard wastes.

Size, Shape and Color...

• Here is another set of interesting facts about sponges. The bodies of sponges are hollow and adapted to maximize the efficiency of water flow through their body. Moreover, they are held in shape by a gelatinous matrix of mesohyl tissues.
• Sea sponges attached to the ocean floors are really colorful and endearing in appearance. They appear dark underwater due to the presence of a dark membrane which envelops them and protects their inner soft skeleton from destruction. Each sponge variety has a different shape and color.
• Sponges have scores of holes or pores on their surface, through which water containing food and oxygen flows throughout the body of the sponge.
• Sea sponges may be found growing on rocks like moss, while some may be freestanding. They grow in strange shapes and sizes, with some reaching gigantic proportions as well. The different shapes of sea sponges are barrels, tubes, etc. One of the largest sponges ever was almost 10 feet wide.
• What we think is sea sponge lying on the beach is actually just its skeleton. The skeleton is composed of needle-like splinters called spicules and a mesh of protein called spongin. A microscopic examination of this skeleton can tell us which kind of sea sponge it is.

Defense...

Sponges can be attacked by predators or even other sponges near them. So to protect themselves, sponges release toxins into the surrounding water and outside their bodies. This also prevents the cells of other sponges from growing. It is because of these toxins that people handling sponges develop rashes after contact.

Reproduction in Sponges...

• One of the interesting sea sponge facts is the way the sponge reproduces. Sea sponges mainly have both sexes in the same sponge (hermaphrodite), however, they produce only one type of gamete per span. This means some sponges act as the male and some as the female, even though they are capable of playing either role.
• Sponges reproduce sexually by releasing a sperm into the water, which is then caught by the neighboring sponges. The sperm fertilizes the egg internally and develops into a minuscule larvae that gets released into the water. The released larva goes and attaches itself to the ocean floor and develops into another sponge.
• When a part of a sponge breaks off, the broken part will form a new sponge, thereby forming another way of reproduction called budding. This power to regenerate is simply remarkable and helps keep the sponge population in control.

Commercial Uses...

• Due to the soft texture, grass and wool sponges are used for bathing. Similarly there are another 4 species that are also used for bath sponges. The yellow sponges with their rough texture and perfect for exfoliation. Having said this, one cannot take a sea sponge from the ocean and use it. Sponge fishermen macerate the sponges collected from the water by squeezing it in buckets of water. They then have the elastic skeleton decalcified, rinsed and bleached.
• Sea sponges are also used in the medical field, where surgeons use sponges during surgical procedures. After all, sponges have wonderful absorbent qualities. Moreover, pharmaceutical companies are conducting several studies based on certain compounds found in sea sponges. Researchers believe that some of these compounds can help prepare antiviral medication to treat conditions like tuberculosis, malaria and cancer.

Since sponges can be rough and abrasive for some with sensitive skin, one should always check with their health care provider before using sea sponges on their bodies. Moreover, people handling sea sponges need to be careful as the toxins can cause a skin rash. You could even use sponges to paint. The next time you pick up a sponge for cosmetic purposes, painting or cleaning, remember these sea sponge facts.