Starfish are echinoderms capable of “autotomy.” During low tide, we often find these hand-sized creatures, resembling five-pointed stars, on the beach or in rocky crevices. This is the starfish.
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| Starfish are echinoderms capable of “autotomy.” (Photo: reef.geddis) |
The body of a starfish has five symmetrical arms (or multiples of five), and these arms serve as its legs when it moves. When crushed by a rock or bitten by a predator, it can automatically sever that arm to escape. Starfish have a strong regenerative ability, and after a period of time, a severely injured arm can regrow to its original length.
The upper surface of the starfish is slightly raised, with a yellow or orange color, while the underside is flat with a mouth that has a beautiful appearance. Starfish are carnivorous marine animals that prefer to eat shellfish like clams, oysters, and mussels. When food is scarce, they even resort to cannibalism, eating their own kind, and sometimes even their offspring.
Starfish possess a type of tissue that allows them to consume hard-shelled creatures. When they catch a clam, for example, they use their arms to tightly embrace the prey until the clam can no longer withstand the pressure. When the two shells open, the starfish takes the opportunity to secrete digestive fluids that paralyze the prey, extending its stomach out of its mouth and into the gap between the two shells to slowly digest the clam’s flesh. As a result, starfish are considered pests in clam and oyster farming. Many fishermen despise starfish for stealing their farmed shellfish and eating their bait. When they catch a starfish, they cut it into many pieces and throw it back into the sea, but this only accelerates the starfish’s reproduction since they have a very powerful regenerative ability.
Structure of Starfish (Photo: infovisual.info)
