Dugong has 1 haplotype, also known as mermaid. Dugong is spindle-shaped, with a body length of 2.5 ~ 3.2 meters; Small head, small eyes, no outer ear shell; The kiss is short and blunt, and the muscles of the nasal passage contract, which can seal the nasal passage and prevent flooding; The whole body is brown or gray, almost hairless, and there is only a sparse beard around the mouth; The forelimbs are paddle-shaped flippers, and the hind limbs disappear; The stomach is divided into cardia and pylorus, and pylorus has two blind sacs. The small intestine is about 10 meter long and the large intestine is 23.6 meters long. It has a conical cecum, which is characteristic of the digestive tract of herbivores.
Dugong is distributed on the east coast of Africa, passing through the Indian Ocean and the southeast coast of Asia to Guangdong and Taiwan Province provinces in the south of China, to the Philippine Islands, the northern coast of Australia, the Pacific Islands in the south, and to the Ryukyu Islands in the north. Habitat only in the ocean, rarely in fresh water. Eat seaweed and shallow water plants. Dive to the depth of 30 ~ 40 meters to find food. You can dive 1 ~ 10 minutes, float to the surface for air, and then dive. After a big meal, lie down among the rocks and be as quiet as a rock. No migration. Usually in groups of two or in groups of three to six people. Swimming mainly depends on the tail fin swinging, and the swimming speed is slow. Pregnancy 1 1 month, fetus 1. Oil is like cod liver oil, which can be used as medicine (nutrition). The meat is delicious and the skin can be tanned. It has been listed as an internationally protected animal.
dugong
Mermaid, alias, belongs to Dugong family, and its scientific name is Dugong.
Dugong's body is spindle-shaped, about 3 meters long and weighs 300~500 kilograms. There are sparse short fine body hairs all over the body. There is no obvious neck, the head is small, the upper lip is horseshoe-shaped, the snout has bristles, and the front end of the head is juxtaposed with two approximately circular breathing holes; There is no external auricle, and the ear hole is located behind the eye. There is no dorsal fin, and the flippers are oval. The caudal fin is wide, the left and right sides are flat and symmetrical, and the rear edge is forked and engraved. There are a pair of breasts under the flippers. The back is mainly dark gray, and the abdomen is slightly shallow.
Dugong is a marine herbivore. Its distribution is closely related to water temperature, ocean currents and algae as the main food. Most of them haunt seaweed about 20 m from the coast, sometimes they enter the estuary with the tide, and then return to the sea with the ebb tide after foraging, and rarely swim out to sea. Living in a family group with 2-3 heads at the bottom of a well-hidden seaweed area, they regularly come out to breathe, and are often regarded as "mermaids", leaving many beautiful legends to people. Dugong is a marine animal evolved from terrestrial herbivores. It has been severely hunted and killed, and the resources have been destroyed. It is urgent to strengthen protection. Produced in Guangdong, Guangxi, Hainan and the southern coast of Taiwan Province Province. It belongs to the national first-class protected animals.
Dugong is the only herbivorous mammal in the vast ocean, belonging to the order Manatee. The biggest difference between manatees and animals such as manatees is that the tail of manatees is round, while that of dugong is similar to that of dolphins. Dugong's head is very big, and the ratio of head to body is the largest among marine animals. The mouth is very strange, huge and vertical, and the tongue is big, which makes it easier to eat marine benthos and exclude sand. When dugong eats, he can see it passing through the foggy dust, which is very beautiful. Dugong's stomata are on the top of the head, and it takes air every 15 minutes on average. The skin on the head and back is extremely hard and thick, which is used to protect themselves and their children and make sharks helpless.
Little dugong's life is fragile, his skin is very thin, and he often dies easily in the mouth of sharks, so little dugong needs a lot of nutrition to grow up quickly. Dugong needs to live with her mother on average 1.5 to 2 years before weaning, and her mother eats several times as much as usual during breastfeeding. The average life expectancy of dugong is 78 years, which means natural death of course. Dugong teeth have sharp side teeth like elephants. These teeth mainly play the role of fighting for spouses and defending enemies, so the fangs of males are longer than those of females.
Dugong is never picky about food. Their favorite food is seaweed, but they often try other marine benthos and live in coastal waters rich in plants. They are shy by nature, as long as they are slightly frightened, they will run away immediately, so under normal circumstances, they will not see dugong. Dugong in lactation will take their children swimming in shallow water. At this time, the nipples of the adult dugong were swollen, which was seen by ancient sailors in poor light and mistaken for women. Dugongs have always been called "mermaids" because of the rendering of legends, but as can be seen from the title map, they obviously have nothing to do with beauty.
Dugong is mainly distributed in the southwest Pacific Ocean and the Indian Ocean coast. Groups of dugongs are foraging and playing in shallow waters, ranging from a dozen to more than 200. The scene is very spectacular. However, human activities are threatening dugong's living environment, and dugong is also experiencing the experience of manatees a few years ago. At that time, manatees were on the verge of extinction due to a large number of new docks, offshore industrial pollution and a large number of fishermen's killing. Thanks to the government's timely stop, they were saved from extinction. Now dugong is also under these three threats. The number of dugongs is less than that of manatees and their vitality is weaker than that of manatees, so the situation is even more dangerous. We can often see terrible marks of propeller damage on the dugong's back in the offshore area. In the industrial polluted offshore, the vegetation on the seabed was completely destroyed, and dugong was threatened by hunger and had to move out of his home. Only from 1995 to 1997, there were three large-scale migration of dugong in Australia. Fishermen used hooked fishing nets and killed a lot of dugongs. Because little dugongs can't survive without their mothers before they reach adulthood (even if they are breastfed, their condition can't get better), so as long as an adult female is hunted and breastfed, it means the death of a group of little dugongs.
After the manatee tragedy, the danger dugong faced was more and more recognized by human beings. China listed Dugong as a national first-class protected animal and established a special nature reserve in Hepu, Guangxi. The Australian government demolished several docks and prohibited pollutants from entering the sea directly. Fishermen in many cities have consciously abolished fishing with hooks and nets, and the government has explicitly ordered that dugongs should be released immediately if they are caught. However, the situation of dugong is still not optimistic, and the decrease of population may lead to the extinction of the whole population due to inbreeding. Like many marine animals, dugong, which is already scarce, needs more care and protection.