Category Zoology

Dainty but Deadly

Some of the daintiest creatures in the sea are the deadliest to small fish and shrimp. Both the sea anemone and the jellyfish look like pretty flowers, but they sting their prey with poison.

The sea anemone got its name because it looks like the flower called an anemone. The animal lives on the bottom of the sea, often in a warm coral reef or a rock pool. A sea anemone can move slowly, but it prefers to stay in one spot.

To catch small fish and shrimp to eat, the sea anemone spreads out its arms. Those arms are filled with tiny stinging parts. When the anemone touches its prey, it shoots out a poison. The poison stops the creature from moving. Then the sea anemone uses its arms to carry the creature to its mouth.

The jellyfish looks like an upside-down tulip. Its body is like a see-through umbrella with long strings hanging down. The jellyfish is made mostly of water. Washed up on the beach, it looks like a lump of colorless jelly.

The jellyfish swims by opening and closing its whole body. When it stops moving, it sinks to the bottom. As it drifts down, it catches small animals by stinging them with its tentacles.

Starry Creatures

What kind of animal has eyes and feet on its arms and pushes its stomach out of its body when it eats? A starfish!

Starfish have tough-skinned bodies shaped like a star. They usually have five arms, sometimes more. Underneath each arm there are little tubes. These are the feet of the starfish. And the small reddish spots at the end of each arm are its eyes!

When it finds a clam, the starfish climbs on top of it. Its tube feet stick to the clamshell like glue. Then the starfish slowly begins to pull the shell apart. Soon the shell is a little way open-just a tiny crack. The starfish then pushes its stomach through an opening in its body and between the two halves of the shell. Juices from the starfish’s stomach turn the clam to mush. The starfish digests, or breaks down, the clam inside the clam’s own shell.

If a starfish loses an arm, it grows a new one! In fact, if the starfish is torn in two, each half grows into a new starfish.

Fuzzy Biscuits and More

The ocean is full of amazing animals. A sand dollar looks like a fuzzy biscuit, but it’s an animal that lives in the sand. It moves about on many feet that look like tiny tubes. People often find the white coin-shaped skeletons of sand dollars on the beach.

A sea cucumber isn’t found in a garden. It’s an animal with a long round body that looks a little like a garden cucumber. At one end are its “fingers” and mouth. The animal uses its fingers to catch food floating in the water. Then it puts each finger, one at a time, into its mouth and enjoys a tasty meal.

Another unusual animal looks like a creeping pincushion. This creature, called a sea urchin, is related to the starfish, but it is round and plump.

Sea peaches belong to the family of animals called sea squirts. Most kinds of sea squirts are just round bodies with two openings like little mouths. One mouth sucks water in. The other squirts water out. The sea squirt eats the tiny animals and bits of plants in the water it sucks in.

Life under a Microscope

If you picked up a cupful of seawater, you might see a few creatures. But, if you looked at the same cup of water under a microscope, you would see hundreds or thousands of little creatures!

Some of the creatures are tiny animals. Some are the young of bigger animals. You’d also see living things like plants. Huge masses of these animals and plants drift in the ocean. Together they are called plankton. Plankton is food for a great many sea creatures, from shrimp to whales.

In a cupful of pond water you would see different creatures. One looks like the bottom of a shoe. It’s called a paramecium and has no head and no legs. It doesn’t have eyes or a mouth either. Its body is covered with rows of little hairs called cilia that it uses like oars to move through the water.

Another creature looks like a funnel with a long tube. It creates a little whirlpool around the top of the funnel to draw food into its body. This creature is called a vorticella.

Another creature found in ponds is an amoeba. It looks like a blob of grey jelly, and it changes shape every time it moves.

Even though these creatures are microscopic, they are an important part of the world of animals. Without them, many other animals would go hungry.

An Underwater Garden

When is a garden made of animals? When it is made by tiny animals called corals! Beautiful “gardens” cover the seafloor in warm, shallow parts of the ocean.

Thousands of corals live together in colonies. Coral colonies are made from limestone. The limestone forms a home where the corals live. Coral colonies can be shaped like fans, beach balls, candlesticks, and other shapes. They can be red, pink, orange, blue, green, or purple.

Each individual coral is called a polyp. Corals are actually relatives of jellyfish. Like jellyfish, coral polyps send out special feelers that sting tiny ocean creatures. The polyps eat these creatures.

Together, many corals form a coral reef. Coral reefs are the richest parts of the ocean. They provide a home for countless fish and other ocean animals. Many colourful creatures live and hide in the crevices and tunnels created by coral.

A Real Live sea Monster

It has eight long, rubbery legs and two huge, staring eyes. The octopus is so scary-looking to some people that it is sometimes called the devilfish. But octopuses rarely attack people. They use their strong arms, called tentacles, to catch shellfish and swim away from danger. Some kinds also have a poisonous bite.

There are about 50 kinds of octopuses. Most of them are about the size of a kitten. But some measure 8.5 metres from arm tip to arm tip.

The octopus is a mollusc. It has no bones, but a tough covering called a mantle protects its body and gives it shape. Rows of round muscles under each arm act as suction cups. These suckers can hold onto an object even if the octopus’s arm is cut off!

When an octopus is frightened it produces a cloud of inky liquid. The inky liquid makes it hard for an enemy to see or smell the octopus. That’s how the octopus gets away.