INVERTEBRATES

Mammals, amphibians, reptiles, fish and birds all have backbones. All these animals make up less than 4% of the total animals species. Over 96% of all the animal species on earth are invertebrates. Invertebrates are cold blooded animals that do not have backbones and do not have a skeleton of bone, either internal or external. Some have fluid-filled skeletons, while others have hard exoskeletons, or outer shells.Mammals, amphibians, reptiles, fish and birds all have backbones. All these animals make up less than 4% of the total animals species. Over 96% of all the animal species on earth are invertebrates. Invertebrates are cold blooded animals.

SQUID

Many-tentacled creatures that belong to the order Teuthida, squid are fascinating ocean dwellers, even achieving mythical status in our minds when we think of certain species like the giant squid. This order of molluscs, which is made up of approximately 300 recorded species so far, is similar to octopi and cuttlefish in that they have a distinct head, a symmetrical body structure, a mantle, eight arms, and phenomenal swimming abilities. Squid are different from their ancestors and many other molluscs, however. In squid, the typical mollusc ‘foot’ structure has evolved. Squid usually have 8 paired smaller arms and two longer tentacles, and highly developed sensory organs.

TARANTULA

Like all arthropods, the tarantula is an invertebrate that relies on an exoskeleton for muscular support. Like other Arachnida a tarantula’s body comprises two main parts, the prosoma (or cephalothorax) and the opisthosoma (or abdomen). Spiders are invertebrates but are not considered insects because they only have two main body parts instead of three, eight legs instead of six and no antennae. Most spiders also have eight simple eyes, while insects have large, compound eyes. Some have no eyes and others have as many as 12. Spiders, along with ticks, mites, harvestmen and scorpions, are called arachnida.

SPIDER

Spiders are invertebrates but are not considered insects because they only have two main body parts instead of three, eight legs instead of six and no antennae. Most spiders also have eight simple eyes, while insects have large, compound eyes. Some have no eyes and others have as many as 12. Spiders, along with ticks, mites, harvestmen and scorpions, are called arachnida. They are also classified into a special group called araneae because they have very slender waists compared to other arachnida. Spiders are found worldwide on every continent except for Antarctica, and have become established in nearly every habitat. Over 43,000 spider species have been recorded.

SCORPION

Scorpions are predatory arthropod animals of the order Scorpiones within the class Arachnida. They have eight legs and are easily recognized by a pair of grasping pincers (claws) and the narrow, segmented tail, often carried in a characteristic forward curve over the back, ending with a venomous stinger. They have adapted to a wide range of environmental conditions and can now be found on all continents except Antarctica. Scorpions did not occur naturally in Great Britain, New Zealand and some of the islands in Oceania, but now have been accidentally introduced in some of these places by human trade and commerce.

SPONGE

While sponges may look plant-like, they are multi-cellular animals that have bodies full of pores and channels allowing water to circulate through them. Sponges are bottom-dwelling sea creatures. They do not have nervous, digestive or circulatory systems. Instead, they obtain nourishment and oxygen from water constantly flowing through them. The flowing water also carries out waste products. There are many different types of sponges in the world's oceans. Sponges come in two basic types: encrusting or free-standing.

CLAM

Clams are invertebrates. Invertebrates are animals that do not have a backbone. Clams belong to a group of invertebrates called mollusks. There are over 100,000 kinds of animals or species in the Mollusca phylum or category. Clams are also known as shellfish. The term shellfish includes members of the mollusk phylum and the crustacean subphylum. Crustaceans include lobsters, crabs and shrimp. Crustaceans are really more related to insects than to clams. Some shellfish or mollusks only have one shell, such as snails. Clams have two shells so they are known as bivalve mollusks. The shells are held together with a hinge.

CRAB

Crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" (abdomen), usually entirely hidden under the thorax. They live in all the world's oceans, in fresh water, and on land. They are generally covered with a thick exoskeleton and have a single pair of claws. Many other animals with similar names – such as hermit crabs, king crabs, porcelain crabs, horseshoe crabs and crab lice – are not true crabs. Crabs vary in size from the pea crab, a few millimeters wide, to the Japanese spider crab, with a leg span of up to 13 feet.

LOBSTER

Lobsters are found in all oceans and found on land. They live on rocky, sandy, or muddy bottoms from the shoreline to beyond the edge of the continental shelf. They generally live singly in crevices or in burrows under rocks. Like most arthropods, lobsters must moult in order to grow, which leaves them vulnerable. During the moulting process, several species change color. Lobsters are invertebrates with a hard protective exoskeleton. In general, lobsters are 10 to 20 inches long.

STARFISH

Starfish, or sea stars, are star-shaped echinoderms belonging to the class Asteroidea. About 1,500 species of starfish occur on the seabed in all the world's oceans, from the tropics to frigid polar waters. Starfish are marine invertebrates. They typically have a central disc and five arms, though some species have more. The aboral, or upper, surface may be smooth, granular or spiny, and is covered with overlapping plates.

CORAL

Corals are marine invertebrates in the class Anthozoa of phylum Cnidaria. They typically live in compact colonies of many identical individual polyps. The group includes the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton. Corals are sessile, which means that they permanently attach themselves to the ocean floor, essentially "taking root" like most plants do. We certainly cannot recognize them by their faces or other distinct body parts, as we can most other animals. So what exactly are corals? Corals actually comprise an ancient and unique partnership, called symbiosis, that benefits both animal and plant life in the ocean. Corals are animals, though, because they do not make their own food, as plants do.

OCTOPUS

The octopus is a cephalopod of the order Octopoda that inhabits many diverse regions of the ocean, especially coral reefs. The term may also refer to only those creatures in the genus Octopus. In the larger sense, there are 289 different octopus species, which is over one-third the total number of cephalopod species. Octopuses are characterized by their eight arms (not tentacles), usually bearing suction cups.