Animals - Invertebrates

• lack of a backbone.
• makes up almost 97 percent of all anmial life.
• sponges, corals, worms, snails, starfish, squid, octopus, insects.

Mollusks 软体动物

• slugs, snails, oysters, clams, octopuses, squid, cuttlefish.
• most have a soft body and muscular base called a foot. Many have protective shells and feed using a moving ribbon of teeth called radula.

Arthropods 节肢动物

• four out of five animal species are arthropods.
• insects, spiders and crabs.

Echinoderms 棘皮动物

• bodies are usually formed from five equal parts arranged in a circle.
• starfish, sea cucumber, urchin, feather star

Cnidarians 刺胞动物

• jellyfish, hydroid(水螅), sea anemones(海葵), corals

Coral reef: covering 1% of ocean floor but home to 25% of all marine creatures.

Worms

roundworms, segmented worms, flatworms.