Phylum Echinoderm – Erakina

Phylum Echinodermata or Echinoderm is a species of marine animals that are invertebrates(Spineless) in nature. The species contain Asteroidea(Starfish), Holothuroidea( Sea Cucumber), Echinoidea(Sea Urchins), Crinoidea(Crinoids), Ophiuroidea(Brittle Stars), etc. 

Echinoderm comes from the Greek word Echinos: “Spiny” and Derma: “Skin”. Spiny skin is nothing but the body structure of Echinoderm which is replaced for the spine. Echinoderms were found in the period of Cambrian Period (542 million to 488 million years ago) where some of them are extinct. The fossils of the Echinoderm were found in the rocks of the ocean.

Types of Echinoderm

The Phylum Echinoderms can be classified into 2 types based on their activities. They are,

1. Eleutheroza is echinoderms that can move. This group includes the Starfish and most other Echinoderms. 
2. Pelmatoza is motionless echinoderms. This includes Crinoids, such as Feather stars.

Seastar or otherwise called Starfish is an aquatic organism that has a body shaped like a star. They measure 20 to 30 cm and some are even less than that. They have spiny skin and Tube feet which are called Podia. By using the tube feet and the spiny skin they can swim forward and move backward without even turning. With the help of tube feet, they can able to move any steep surface. The lower side of a starfish contains thousand of tube feet in each arm which is responsible for their quick and easy movements. There are some kinds that can able to live offshore and some do not. A starfish can able to stay in ocean depth at least  6000m. The reproduction of an echinoderm takes place by releasing its eggs and sperm into the water. They can also reproduce asexually.

Crinoids an echinoderm that is under Pelmatoza have a body structure similar to a starfish but have different characteristics. The structure looks like a Stem with arms that contain feathery projections (pinnules) that contain more tube feet with sensory functions. They mostly found 9000 m under the ocean. They produced major carbon in the Mesozoic periods. They sometimes attach themselves to floating objects and sides of the fish to move.

The sea cucumbers don’t have brains but they have serious nerve systems that can detect predators. They are sensitive to light. 

Characteristics of Echinoderms

Their species are different than the other Aquatic organisms. Let’s see some of their characteristic behavior

1. Their defense mechanism is even dangerous for humans and for their Predators.
2. They filter their food using brushes in their mouth.
3. Their movements are based on their tube feet.
4. They have a unique body structure than others.
5. They can able to regenerate their body organs.
6. Its development is not direct.
7. They possess spiny skin.
8. The body of them is unsegmented with no distinct head.

These characteristics make them adorable and cautious too.

Uses of Echinoderms

The echinoderms are useful for humankind and to nature. They are

1. They are an important part of the ocean food chain.
2. Their burrow themselves under the depth of the sea to produce oxygen for sea floors.
3. They eat Seaweed.
4. Echinoderms are scavengers of the sea. They prey on the decayed matter on sea floors.
5. Sea cucumbers toxin is used for slowing down the growth of Tumour cells.
6. The hard skeleton of some echinoderm is used as Lime in farming.
7. In some countries, echinoderms are considered delicacies.
8. They maintain seafloor consistency.
9. The starfish prevent the growth of Algae.
10. Sea cucumbers provide a habitat for crabs, worms, and snails.

Pet for humans

People have the tendency of treating fellow human beings with love and nourishment. People like to have pet animals of different kinds. Some like Dogs, Cats, Rabbits, Pigs, Fishes, etc.

The atmosphere of an echinoderm life is not well supported for humans. Petting an echinoderm is not easy. Mostly in Aquarium, they maintain the water level to 72 to 78 degrees Fahrenheit for creating a sensible environment and they keep the salinity levels for the fishes.

The echinoderms are the species that lived long enough and produced fossils for humans from beyond time. There are some species that lived in the past that are still present in the future. So let’s prevent extinction so that our future generation can able to see the real and not photographs.