Coral stories you don't know
Noble and elegant, the red coral with strong colors, with its unique connotation, shocking dazzling red, has always been loved by people. Especially in recent years, coral is more sought after by consumers, I believe that we have learned a lot about coral knowledge through the Internet, such as the identification of corals, the commercial grading of corals: Aka, Momo, sardine, etc. Today we do not talk about these, let's talk about the untold story behind the dazzling coral jewelry that we see.
What exactly is coral?
Because corals cannot move, and because they look like flowers and trees, it is easy to be mistaken for plants that grow on the seabed. In fact, the polyp is a fixed animal, a marine invertebrate of the phylum Phylum Polyps, with eight or more tentacles, with a mouth in the center of the tentacles, multi-group, combined into a group, shaped like a branch. Characterized by endoskeletons or exoskeletons with calcareous, or leathery, the corals we use as jewelry are a combination of numerous polyp secretions and skeletons.
Growth of polyps
Polyps are only hydra-shaped individuals, hollow cylindrical in shape, with the lower end attached to the surface of the object, the top with a mouth, and a full circle or multiple circles of tentacles. Tentacles are used to collect food, can be used for a certain degree of stretching, food enters from the mouth, food residues are discharged from the mouth, such animals have no head and trunk, no nerve center, only diffuse nervous system. When stimulated by the outside world, the entire animal body responds. Juvenile polyps can float in the sea and, as adults, are fixed in the underlying habitat (Figure 1). New polyps continue to grow, and old polyps die, but their bones remain in the colony and grow as a result. Figure 2 shows the body structure of the polyp.
Figure 1 Body structure of polyps
Fig. 2 Structure of the polyp
Corals grow so slowly that it is difficult to tell the age of corals from a particular branch, and corals over a kilogram are undoubtedly centuries old.
Corals inhabit tropical and subtropical waters and form in shallow areas of abundant sunshine and clear water. Its vertical distribution is limited to 60 meters, and it grows best at depths of about 30 meters. Because the shallow sea area is the penetrating layer of sunlight, which is conducive to the photosynthesis of symbiotic algae in the coral, the shallow sea area provides a rich food source and sufficient oxygen for the coral due to tidal action and wind and waves, and the vibration of the sea water provides a rich food source and sufficient oxygen, and it is easy to remove metabolites. Temperature is a restrictive factor affecting the growth of reef-building corals, only the annual average temperature of seawater is not less than 20 °C, corals can build reefs, its most suitable temperature range is 22 °C ~ 28 °C, so coral reefs, coral islands are distributed in tropical and subtropical seas. Its habitats are: Mediterranean Sea, African Red Sea, Spain, Australian Great Barrier Reef, Japan's Ogasawara Islands to the Ryukyu Islands, Taiwan (Keelung, Kaohsiung Xizi Bay, Pingtung Kenting and Penghu Islands), South China Sea and Caribbean Sea.
Varieties of coral
There are many varieties of corals, usually including soft corals, gorgonian corals, red corals, stony corals, horn corals, hydra corals, flies and sheng corals. There are about 1,000 species of stony corals (stony corals), about 1,000 species of black and spiny corals (horned corals), about 1,200 species of gorgonian corals (gorgonians), and only one species of blue corals (flies).
Our common ruby red corals are species of the genus Red Coral in the family Gorgonianaceae, in addition to the black corals of the order Horned Corals, the golden corals of the Golden Tree family, and the only species of blue corals of the order Bleeps.
Source of graphics / National Inspection Training Center