Popularly referred to as Sponge Bob – sponges are the real deal! They are animals that grow in all shapes, sizes and shades – but remain fixed in one spot (unlike the cartoon). A sponge’s body is made of cells, but it has no nervous system, brain, heart or muscles. Of the more than 10,000 species worldwide, some can grow larger than a human.
Sponges are filter feeders – they take in water through the tiny pores across their body, and filter out their meals of bacteria, then the water is passed back out again through the big hole in their centre. Some sponges can pump up to 10,000 times its own volume. This means that a sponge the size of a milk bottle can pump enough water to fill a small swimming pool! Other species have fine tentacles that can trap tiny crustacea and plankton.
Sponges are interesting because they can reproduce in several ways. Some create new buds (or those that break off accidently) can grow into new whole sponges. Yet other species release sperm which are then captured by other sponges; the sperm cell is passed on to egg cells, then both attach to a larvae that swims off to settle and grow into a new sponge. Some release both sperm and eggs, which attach to each other outside the sponge before settling down to grow.
Kelab Alami conducts guided habitat immersion tours that allow you to meet and examine these fascinating creatures. Log on to kelabalami.weebly.com for more information.