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Coral reefs are made by small animals

Coral reefs are rocks, undoubtedly made of limestone, but they are made by living organisms. They are living organisms that are alive as long as they remain in the water. If they are taken out of the water, they die.

They are small neighborhoods. The living organism begins its life from it and has the typical consistency, oval in shape. Its length is a fraction of an inch. It has hairs with which it swims in the water.

(To the right: An individual coral, one of those that lives alone, in which you can see its structure arranged in beautiful segments with axial symmetry in the spectrum. The left picture shows a coral colony, the members of which live, and they are extremely zero, in cups that resemble zero and fineness, and they appear like grains on branches. from trees)

It is a moving animal.
Then he seems to settle down.
Then he lands on the rock where he was in the sea, and then begins to build a house for himself. He makes the bottom of this house first, a layer of lime (calcium carbonate) that he secretes that is between him and the rock, which is the base of the house. It also secretes a layer of lime that circulates around its body. The body takes the shape of a dome, wide at the bottom, narrow at the top.

The scientist searches for this body and finds it to be something like a bag.
It has no opening except at the top, which is its mouth. Above the mouth are moving appendages, known as palps, six in number from true corals. They sense the food in the sea and carry it to the inside of the bag. These tentacles have cells that secrete poison, which they carry from them to the small victim floating in the sea. Hairs emerge from these tentacles, killing them before they devour them.

It is an empty sac of entrails that grabs food and digests it with the digestive juices that ooze from the inner walls of the sac.

This living creature, with its bag, stands in its limestone structure that covers it, except for its head, as a self-contained unit.

Scientists call it a polyp, and its origin is Polypodus, which is a Greek word meaning many legs. The legs are nothing but the movable appendages near its mouth. You may see them as hands, but the one who coined this first word saw them as legs.

Therefore, some Arab scholars Arabized the polyp as meaning the one with legs, as the philanthropist says, meaning the one with great benevolence. And the inlaid and the cup. Thus, we create a term that bears an inherent characteristic of this animal, and has an unbroken connection with the Western word, which is the source of present knowledge.

- Units, repeated to form colonies

These animals interact with each other, billions upon billions, and form colonies. These living things die, and are succeeded by others, and then others.

Thus, coral reefs are formed in the seas, over generations and centuries.

These units of these animals may live an interdependent life, and channels exist between them that carry food from one neighborhood to another. Each hunts, each feeds, each lives, and some have their access to sea water blocked, and yet their sustenance comes to them in abundance.

In any case, this is a cursory description and does not include everything
It is told about the characteristics of corals, their reproduction, and their differences
Varieties.

(Coral colony, fan-shaped, dark purple in color)

- Rocks on which life flows slowly, and the one who looks at them thinks that they are like all other rocks, inanimate. Because of the zeroness and minuteness of these living things, and because of their stability and lack of movement, and because of their lack of gravity, attributed to the huge mass on which they lie, made of rocks made by their ancestors long ago, because of all this, the eye of man cannot see them. What is normal about these rocks is what makes him feel the presence of life, unless he finds the appearance of a collected plant, and he thinks it is a plant, as it has stems, and what looks like leaves and flowers.

It has the most beautiful colored rocks. He thinks the color came from the sea. Color only came from the life of these living things, as they are the ones who created it.

These types of coral organisms. And for each type
Selected colour.
The rocks emerge from the water and most of their color disappears.

(Another colony of living corals, in which you can see individual corals with their sensitive appendages (palps) extended outside their tubes, which are made of lime.)

Coral rocks only occur where it is warm

Coral rocks are abundant in the Pacific Ocean and the Indian Ocean, and they are only found where the water is shallow, so its depth does not exceed 40 or 50 meters, otherwise where the water is clear and warm, its temperature does not fall below 20 degrees Celsius. There is also the Gulf of Mexico and the Arabian Indies.

And let's not forget the Red Sea. The truth is that there are many of them
These rocks make navigation dangerous for non-expert navigators. He who strays from the paved road does not know what he will encounter. Perhaps a submerged coral island suddenly meets him without seeing it.

Every student of geography has undoubtedly heard of the Great Barrier Reef in Australia, which extends about 1,000 miles along the eastern shore of the Australian continent, to the north, and its width ranges between ten and ninety miles.