Sea sponge: what it is and characteristics

Most sea ​​or poriferous sponges do not have body symmetry, except for a few species that show radial symmetry (simple symmetry in which an oral and an aboral body end differ). Its most distinctive characteristic and that gives the name to the edge is that they have bodies that are formed by a system of pores and channels in which the water flows and that serve as a method to feed themselves and obtain oxygen.

As we mentioned, these animals lack true tissues, instead they have a large number of totipotent cells, which are capable of differentiating into the cell type that the animal needs. This characteristic makes them very versatile animals with a great capacity for body regeneration , in case of loss of mass.

The shape of the different kinds of sea sponges can vary, however, they all have a similar basic structure. This is a large central hole in the upper part of the body (osculum), which pumps the water that circulates throughout the animal’s body, and body walls filled with pores of different sizes, through which the water circulates.

Among all its cells, there is one exclusive to marine sponges , they are the choanocytes. These are cells that are specialized in filtering water , a process necessary to obtain food. They are cells with a flagellum and microvilli on their surface (as if they were flexible and mobile hairs), which promote water circulation.

Sea sponges are animals with an incredible ability to adapt to a wide variety of conditions and situations, something that would be impossible for other animals. They are capable of living even when the waters in which they live are polluted by hydrocarbons, metals or other substances. Sea sponges have few natural predators, as they have a hard skeleton of spicules and high toxicity. This is why it is possible to find sea ​​sponges in almost all the seas and oceans of the world. Among the sites best known for the large number of porifers present are the Western Mediterranean, the Gulf of Mexico, the Caribbean and the seas of Japan.

However, there is one factor that especially affects sea sponges and that is climate change . Climate change kills thousands of sea sponges a year and some undergo adaptations to survive. Therefore, these marine animals are considered a good indicator of this change.

Since marine or poriferous sponges are sessile animals, they live attached to the seabed, being able to live at great depths or more superficially. Although, most porifers prefer to live in an environment without too much sunlight.

Sponges or porifers feed mainly on small organic particles dissolved in seawater through a filtration mechanism, as we have mentioned before. They can also feed on plankton and small bacteria .

In addition, these marine animals can live in symbiosis with bacteria or unicellular organisms, which facilitate access to food. In addition, many serve as a refuge for a wide variety of fish species.

Another frequent question about these peculiar animals is how the sea sponge reproduces . Thus, answering this question, we clarify that the reproduction of sea sponges can be asexual or sexual.

In asexual reproduction , the totipotent cells in your body differentiate into all types of cells to create a new sponge. For sexual reproduction , although most sponges are hermaphroditic, they need sexual reproduction, in which sperm and eggs develop from choanocytes and are expelled into the water, where fertilization occurs. These then go through four larval phases, until they become the adult individual.

As a curiosity, sea sponges produce toxic substances or antibiotics , many of which are used in the pharmaceutical industry to produce important medicines.

Also, sea sponges have been used for personal hygiene , particularly of the Spongia and Hypospongia genera , since they have a more flexible exoskeleton. Although this use is decreasing due to the growth in the use and production of synthetic sponges.

If you liked to know all this about marine sponges, sea sponges or porifers and you want to learn about the life of the oceans, discover more in this other AgroCorrn article on The biodiversity of the oceans .