Welcome to My Starfish Under Water Grotto ENJOY! :-)

< ------------------------------------------------------------------------------------------------------------------->

STARFISH :-) I chose the starfish for my website because; STARFISH are unique and interesting :-), just like me! TYPES OF STARFISH There are two subtypes of starfish: Asteroideas are the true starfish and sun stars. Ophiuroideas are brittle stars and basket stars. The differences between the two subtypes lies in how the arms connect to the central disk. Ophiuroids have arms that don't connect with each other. There is a distinct boundary between the arm and central disk. Asteroids have arms that are connected to each other. Also, it is harder to tell with asteroids where the central disk ends and where the arms begin.Starfish are in a class called echinodermata (echinoderms).Echinoderm? What does that mean? "Echino" means spiny and "derm" means skin. Starfish (group name Stelleroidea) are sometimes called sea stars or sea fish though it is not a real fish (it doesn't have a vertebrate or fins). Starfish may well be the most unusual well-known creature. They have no front or back.They can move in any direction without turning. Rather than using muscles to move their hundreds of tiny legs, starfish use a complex hydraulic system to move around or cling to rocks. The intake valve for this system is generally located on the top of the Starfish, just off the center.

< ------------------------------------------------------------------------------------------------------------------->

STARFISH REPRODUCTION Starfish commonly reproduce by free-spawning: releasing their gametes into the water where they hopefully are fertilized by gametes from the opposite sex. To increase their chances of fertilization, starfish probably gather in groups when they are ready to spawn, use environmental signals to coordinate timing (day length to indicate the correct time of the year, dawn or dusk to indicate the correct time of day), and may use chemical signals to indicate their readiness to each other. Fertilized eggs grow into bipinnaria and later into brachiolaria larvae, which either grow using a yolk or by catching and eating other plankton. In either case, they live as plankton, suspended in the water and swimming by using beating cilia. The larvae are bilaterally symmetric — unlike adults, they have a distinct left and right side. Eventually, they undergo a complete metamorphosis, settle to the bottom, and grow into adults.

< ------------------------------------------------------------------------------------------------------------------->

DO STARFISH HAVE EYES? Yes, but not eyes as most animals have. Starfish have eyespots at the tip of each arm, which act as light sensors. They contain a red pigment which changes chemically in the presence of light and are thought to influence the starfish's behaviour (particularly movement). CAN STARFISH FEEL? Starfish also possess sensory cells in their skin, which probably function as receptors for light, contact and chemical stimuli. These cells are common on the suckers of the large number of tube feet underneath the animal and are probably used in sensing various surfaces. DO STARFISH HAVE A SKELETON? Starfish have an internal skeleton just underneath the skin. It is composed of blocks of magnesium calcite (termed ossicles) which are arranged as a lattice network joined by connective tissue. In some starfish the space between these blocks is quite small forming plates which make the starfish extremely tough. Some blocks bear spines or swollen projections (tubercles) which give the animal a spiny or warty appearance -- hence the general name, echinoderm (meaning spiny skin).

< ------------------------------------------------------------------------------------------------------------------->

WHAT DO STARFISH EAT? Starfish eat many things. The starfish usually hunts for shelled animals like oysters, clams, barnacles, snails, sea urchins, clams, mussels, and other small animals. A few species, like the spiny star of the North Atlantic, eat other starfish! The starfish waits till it finds a meal. Then it sneaks up on it, jumps on it, and surrounds the shell. After that, it uses its suction cups to pull the two shells apart. The starfish has enough force in its arms to bend the shell of its prey. It pulls until a crack about as thick as a piece of cardboard forms. Using this small gap, the starfish pops its stomach into the shell inside out to dissolve the snack. After ten minutes the stomach is done. The stomach slides itself back into the starfish. When it is done, there is nothing left but an empty shell. PREDATORS AND DEFENSES If a mussel or clam that a starfish eats is sick or dead; the starfish may die :-( . HABITAT/LOCATION The Starfish lives mainly on the bottum of the sea but it also lives in small holes left by other creatures in rocks and coral reefs. The second main place to find starfish is on coral because the starfish is normally eating it :-). The starfish is a very interesting creature who even with its disadvantages in the marine world, still survives and reproduces. I hope I have shared with you some facts about Starfish and informed you of the different aspects of their lives.

My Favorite Links:

Adlai E. Stevenson High School Marine Science / Scuba program

http://www.oocities.org/starfish0966/photopagefloral2.html

I hope you found my website informative and fun :-).

Name:

Emelia (Masry)

starfish0966@yahoo.com

< ------------------------------------------------------------------------------------------------------------------->