Not many sites offer these amazing starfish facts for kids including starfish habitat, diet, reproduction, and types. Through this article you’ll be raising your understanding towards this beautiful marina animal. Starfish or sea stars are echinoderms that belong to the Asteriodae class. These fish are commonly referred to as starfish. There are around 1,800 starfish species worldwide, and most of them inhabits in Pacific, Atlantic, Southern, Arctic, and Indian Oceans. They are found across an extensive range depth range from the intertidal to abyssal depths. Amongst marine animals, starfish are the most common with shared characteristics including feeding on mussels, and regeneration. There is an extensive diversity among feeding approaches and body forms. They are considered to be opportunistic feeders with numerous species having limited feeding behaviors, such as specific predation on a particular prey.
Amazing Starfish Facts For Kids
- The evolutionary ancestors of starfish are considered to be echinoderms and are thought to have had bilateral symmetry. Modern starfish have bilateral symmetry in their larval phase.
- Starfish have five arms and rays that spread out from a central disc. Nonetheless, numerous starfish species have more than six arms. There are few species that exhibit 10 – 15 arms, with the maximum can reach up to 50.
- They have quite a few structures at their body surfaces that consist of simple anatomy of the animal and can for a while support in its identification.
- Modern starfish holds hydraulic water vascular system that assists in locomotion. There are several projections in this system that is known as ventral faces and tube feet which operate in locomotion and support in feeding.
- Not only the body cavity consists of vascular system that functions the tube feet, but they also have a hemal system which is the circular system. Hemal channels generate rings around the mouth, in proximity to the aboral surface and surrounding the digestive system. There is an axial sinus that links the three rings.
- There is a small eye attached to the end of each ray or arm of starfish which enables it to identify a difference between darkness and light. This is effective particularly in locating the moving objects. Only portion of the cells are stained and there is no cornea or iris. This eye is called pigment spot ocellus.
- Starfish pull out numerous kinds of toxins and secondary metabolites.
- The length of the starfish measures around 20 to 30 cm (8 to 12 inches) while some species are only 1 cm (0.4 inch) long, and others are as much as 65 cm (25 inches).
- The body wall of the starfish comprises epidermis, a thick dermis produced from connective tissue and a thin inner peritoneum.
- The starfish mouth is located at base of the body, and opens via a short esophagus into firstly a cardiac stomach, and then a second pyloric stomach.
- Starfish is capable to ingest prey that is larger than its mouth for the reason that it can digest food outside its body. Some of the food sources include small fish, mollusks, clams and oysters. There are few starfish species that are not exclusively carnivorous and they supplement their diet with organic detritus and algae. They are mostly grazers.
- They have a complex nervous system, with a dispersed brain.
- Although starfish do not have several well-defined sensory inputs, they are receptive to light, touch, orientation, and temperature. The spines, tube feet, and pedicellariae are responsive to touch, while eyespots on the ends of the rays are light-sensitive.
Starfish are regarded as generalist predators, consuming mollusks including oysters, snails, clams and those animals that are too slow to avoid attack such as dying fish or echinoderms. Some of the species are detritivores and they tend to eat decomposed plants and animals or organic films anchored to substrates. Other fish may include coral polyps and plankton.
Where Do Starfish Live
These species are believed to reside in almost all the ocean waters with the greatest diversity are found in the tropical Indo-Pacific. Some other regions where starfish are normally found are tropical-mild areas surrounding Australia, the tropical East Pacific and the cold-temperate water of the North Pacific ranging from California to Alaska. Their habitats include mud and sand, kelp forests, seagrass meadows, tropical coral reefs, gravel, shell brash, and the deep-sea floor.
Reproduction | Starfish Facts For Kids
The majority of the starfish species are dioecious, with distinct female and male individuals (also called gonochoric). Apparently male and female are not distinguishable from the outside and one need to observe the gonads or spawning. Some of the species display internal fertilization. The starfish brood their egg by sitting on them normally raise their disc and presume a humped posture.
How Long Do Starfish Live
The lifespan of starfish differs significantly between species, normally being longer in greater species. The adults (weighing 2 g) become mature in 2 years age, and can survive up to 10 years while those weighing (80 g) reach the maturity age in five years, and can survive up to 34 years.
Starfish have the strange ability of regenerating their lost arms even though this aptitude has been observed only in few species. In the primitive stages of starfish, they are rather more prone to infections after the loss of an arm.
Threats | Starfish Facts For Kids
The starfish population is affected by the water pollution since they have little ability to filter out water of toxins and containments. Human activities such as oil spills and similar events are responsible for the decontamination of water.
Types of Starfish
- Blue starfish
- Carpet starfish
- Chocolate chip starfish
- Comb starfish
- Common starfish
- Eleven-armed starfish
- Ochre starfish
- Pink starfish
- Horned starfish