Sea sponges are stationary organisms that must plant themselves in an area of the ocean where they can get ample amounts of food. Rather than hunting for food, sea sponges bring sea water into their bodies and pull food and oxygen from the water. As water flows back out of the sponge, it carries with it carbon dioxide and other waste. Sea sponges come in a wide array of colors, sizes and shapes.
Plant or Animal?
Although they do contain chlorophyll pigments found in plants, sea sponges are animals. Sea sponges were called zoophytes and considered to be both plant and animals until late in the 1800s.
Scientists estimate that there are approximately 10,000 different species of sea sponges. Only 6,000 of these species have been discovered.
Sea sponges are categorized as either encrusting or freestanding. Encrusting sponges grow on the surface of rocks and other underwater debris. Freestanding sponges do not need to grow on top of other objects. Freestanding sponges get much bigger than encrusting sponges, and some are large enough that a person could stand inside of them.
To avoid predators, sea sponges release toxins into the water around them and have toxins covering the outside of their bodies. People who handle sponges or brush up against them may develop a rash because of these toxins.
Pharmaceutical companies are experimenting with certain compounds found in sea sponges. It is believed that some of these compounds may be able to help combat malaria, tuberculosis and cancer. Chemicals from sea sponges are already used to make some antiviral medications.
Every individual sea sponge is both male and female. Although the sponges cannot reproduce by themselves, they can play the role of a female during one reproductive cycle and then play the role of the male in the next.