Every night, one or two people on duty walk around the garden with flashlights. The 86-hectare garden was dark and there was only a beam of light at the foot, but the night watchman was not alone. The eyes of thousands of animals are watching the moving light.
The world heard by the night watchman is small, dense and lively: insects are singing one after another in the grass, herbivores are chewing fresh grass leaves and tender leaves, sometimes wolves are howling, and sometimes gibbons are singing. In the eyes of animal researchers, gibbons' melodious songs are one of the few animals that can be called "singing" rather than "calling". When you pass by the Panda Pavilion, you can hear the squeaking of pandas eating bamboo.
As the earliest modern zoo opened to the public in China, Beijing Zoo is 1 16 years old and undertakes the functions of the national zoo.
Since the founding of New China, most of the "national gift animals" donated by foreign heads of state have to be fostered here. The "national treasure" giant pandas and crested ibis are artificially bred here and then released to nature. Abby Mallard, an extremely endangered species, is even rarer, and the first artificial working group was successfully established here this year.
And the first comprehensive wildlife hospital in China. The scene of an animal doctor seeing a doctor is often a bit funny.
The doctor stood on the second floor, holding an infusion bottle for the baby elephant, invited a doctor of human stomatology to wash the giant panda's teeth, checked whether Malai was pregnant with ultrasonic instruments, performed hernia surgery on polar bears, and took out plastic bags from the belly of wild sheep. This is a "weekend disease" caused by tourists feeding on weekends and holidays.
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A long river named "Long River" runs through Beijing Zoo, one of which happens to be the dividing line between the two districts in Beijing. The Siberian tiger and Bengal tiger on the south bank live in Xicheng District, while the Asian elephant and African elephant on the north bank live in Haidian District. The housing prices in both school districts are evenly matched. The animals don't know that the land under their feet is one of the most expensive in China in terms of house prices.
Three years after the epidemic, Beijing Zoo ushered in the calmest period since its establishment. At the beginning of 2020, it is rare to close the park for three months. Since then, the proportion of tourists' current restrictions has been controlled at 30% and 50%. Up to now, the current limit ratio is 75%. In the first half of this year, the ticket revenue dropped by about 30% compared with the previous two years.
Last summer, for example, only watermelons supplied 396 kilograms a day, and seasonal vegetables 19 kinds, and the daily supply was about 732 kilograms. The daily supply of three kinds of green feed is about 2500 Jin. This summer, Beijing Zoo bought an ice machine to process ice cubes for animals that are afraid of heat.
Waterfowl Lake is the busiest in June every year, 5438+ 10. Breeders and animal doctors put on life jackets, rowed boats, and landed large waterfowl such as pelicans, spotted geese, Canadian geese and swans, and vaccinated them with bird flu vaccine.
For smart guys with small heads, such as mandarin ducks, red-dot ducks and mallard ducks, they can only wait for opportunities with cotton swabs, syringes, measuring sticks and other tools, while they are unprepared to catch them.
At the worst of the epidemic in COVID-19, breeders were divided into two echelons, living in animal sheds or operation rooms with folding beds on their backs, and taking care of animals in a closed way.
This is not the first time that the epidemic has shrouded the land of the zoo. In 2004, due to the outbreak of avian influenza and SARS in 2003, Beijing Zoo was almost forced to move. One of the main reasons for asking Beijing Zoo to move out of the urban area at that time was that if the zoo was located in the urban area, it would pose a threat to public health and safety.
This assertion was refuted by experts and scholars including five academicians: in the history of the development of zoos in the world, there is no precedent for zoos to become places for the spread of infectious diseases.
Chen Junyu, an 87-year-old academician of China Academy of Engineering, recalled to the media the first time he went to the zoo when he was 9 years old. "At that time, there were two giants selling tickets, more than two meters tall and wearing robes. This is very interesting. "
In April this year, actor Liu Changsheng recalled the zoo's "ticket-collecting giant" mentioned by his father in a TV program. As soon as the tourists entered the zoo, the "giant" lowered his head, stretched out his "hand as big as a dustpan" and said in a muffled voice, "Tickets?"
"Giant" does exist. According to the records of Beijing Zoo, from the 1920s to the early 1940s, the predecessor of Beijing Zoo, the Central Agricultural Experimental Field of Qing Dynasty, was changed to the National Museum of Natural History, and four giants over 2m in height successively checked tickets at the gate. "They often bend down to tease the children, and often stand on tiptoe and touch the brick carvings on the gate." One of them made a movie in Hollywood.
When the painter Huang Yongyu was young, he "took twenty or thirty children from the hospital to the zoo with a small flag". This was after the founding of New China.
Even during the Cultural Revolution, Beijing Zoo was still quite lively-1966, and the total number of visitors exceeded10 million for the first time in the history of building the park. Students from all over the country who went to Beijing to visit the Beijing Zoo.
After several storms, this 1 16-year-old zoo still stands in the northwest corner of the Second Ring Road in Beijing. /kloc-for more than 0/00 years, the layout of Beijing Zoo has not changed much from the original agricultural experimental field. The full map of the agricultural experimental field displayed by the Science Museum is superimposed on today's zoo map, and the land and water are almost the same. The archway at the main entrance, the Qianfeng Hall, the Changguan Building in the western suburbs, and the bronze lion and bronze roar in front of the building have all become key protected cultural relics, still waiting for tourists.
The Beijing city outside the zoo wall has never stopped growing. At that time, the western suburbs of Beijing became the center of the city, and a stone bridge was set up in front of the Royal Pier of the Zoo.
Take a cruise from the zoo pier, along the long river all the way to the northwest, and you can go straight to the Summer Palace. This is also the tour route of Empress Dowager Cixi. At that time, Beijing Zoo was also called Wansheng Garden.
The famous zoo wholesale market in front of the main gate was moved to Hebei Province at the end of 20 17. The buses and surrounding subways in the zoo bus hub can reach most parts of Beijing.
In the Spring Festival of the Year of the Tiger this year, in front of the Lion Tiger Mountain, in addition to the children born after 00 and 10, some Beijingers who are no longer young came here to punch in again. In the family photo album, many Beijingers can find a photo with Shihushan.
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Every May and June, many newborn animals appear in Beijing Zoo. 20 1 cute animals were born this year. Compared with the same period last year, this figure is in the forefront, exceeding the total number of animals in the park when 1949 was founded in New China.
At that time, although Beijing Zoo was called "All Animals Garden", there were only over 100 animals left. According to the garden records, sunflower parrot 1, white parrot 1, pink parrot 1, monkey 13, emu 1 (blind).
On June 30th this year, according to the latest monitoring statistics of Beijing Zoo, there were 511species of animals in the park, including 50 species of wild animals under national first-class protection and 60 species of wild animals under national second-class protection.
There are nearly 600 species and more than 5,000 animals in Beijing Zoo. Judging from the population, the species and quantity have declined now.
At that time, there were many "single species and single animals" in the park, which met the demand of people to see "new, strange and special" animals in the zoo. This is what many zoos are pursuing at present, and researchers call it "stamp collecting" zoo.
"But from the animal's point of view, it is not good for their health." Zhang said that Beijing Zoo no longer emphasizes "the most complete species", but pays more attention to population reproduction, communication, protection and wildness, so that animals are no longer lonely. "Maybe it can be understood as the' reduction development' of the zoo."
Since the beginning of summer, the spotted geese have swaggered along the main road with their chicks who have just learned to walk, occupying a lawn on the roadside as a territory, and sometimes walking with tourists. This kind of waterfowl with "two poles" on its head naturally lived in the wetland of Waterfowl Lake before the outbreak.
A mother mandarin duck with her seven little mandarin ducks is sunbathing on the boulder in front of Shihu Mountain. The tourists didn't dodge when they approached to take pictures, and fell asleep with their eyes narrowed.
In addition to the registered animals, there are many wild animals living in Beijing Zoo, which come uninvited.
The red-eyed night heron flew from nowhere, competing with the waterfowl in the waterfowl lake for fishing, and sometimes crouching next to humans on the long river bank.
After the snow in winter, the dead leaves on the tree fell off, and when they got married and had children, a night heron flew to the branches, occupied the land in advance and prepared to build a nest.
Crows, weasels and other outsiders have a "somewhat bloody" lifestyle in the zoo. They often sneak away waterfowl chicks. This year, two striped goose families have been robbed of one goose each.
However, crows will also be countered by the "aborigines" in the zoo. Crows like to steal the meat fed by breeders. Hyenas put the meat bones in front of them, dig holes for catnap, and prey on crows when stealing. The breeder filmed the game of "high-end hunter" and found messy crow feathers in the hyena's nest.
In the rhinoceros arena, wild birds and rhinoceros have long known each other.
The rhinoceros's home is like an oval concert hall, tall and empty, with two floors high. The roof is a round glass cover with a big belly like a brick kiln. Sparrows, magpies and turtledoves often patronize, eating insects on rhinoceros, pulling caterpillars and ladybugs in green feed, and standing by the rhinoceros's sink to drink water.
There are countless ecological communities among 1. 1 10,000 trees, 60,000 shrubs, numerous hedges, perennial plants and lawns in Beijing Zoo.
Managers do not interfere in the communication or "war" between animals. No pesticides are sprayed in the park, and "pest control" is adopted. Gardening workers nailed the silkworm chrysalis of last week's bite wasp to the waist of the tree, which is the natural enemy of the invasive alien species Hyphantria cunea.
Zhang 1989 graduated from Beijing Agricultural University (now China Agricultural University) and worked in Beijing Zoo for 33 years. Now he is a well-known animal expert in the industry. He especially likes to observe birds and small animals in the garden.
Woodpeckers pecked at his feet, not afraid of people. Magpies sometimes fall on his hand, and he can take pictures with his other hand. The timid hedgehog is very picky about the environment. In Beijing Zoo, they can safely climb the lawn from one bush to another.
The persuasion work of zoo staff and volunteers, in addition to epidemic prevention and reminding civilized gardens, also reminds tourists not to "invade" the animal world. "If someone hurts or scares them, they won't be so close to others."
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Shortly after being born in Beijing Zoo, every animal will have a serial number or pedigree number similar to the human ID number, and an interesting name. The interesting degree of a name often depends on the breeder's hobby or brain hole.
When four white rhinos came to Beijing Zoo from South Africa, the keeper Lin Heng was reading Lao She's Camel Xiangzi. He named a rhinoceros 1 year-old "tigress" (the heroine in camel Xiangzi).
"Tigress" has a hot temper. In order to cure her bad temper, he named another little rhino who had been a "tigress" for several days "Grandpa Four". This grandpa four has nothing to do with the TV series The Queen of the Palace, just because Grandpa Si Liu is the father of Tigress in Camel Xiangzi.
Every Spring Festival, Beijing Zoo will choose an animal as the mascot of China New Year Zodiac. This year, in the Year of the Tiger, the Northeast Tiger "Jiansheng" was unfortunately defeated because of his outspoken name, and another Northeast Tiger "MengMeng" was successfully elected.
The breeder of the white-cheeked gibbon likes to eat elbows, so this lovely animal with a white beard is named "elbow". At the time of registration, it was once rejected by the leaders, "it is difficult to be elegant"-the names of many animals should be made public to tourists and animal lovers.
There are almost a full set of "Meng" names for "Internet celebrities" pandas in the zoo: MengMeng, Meng Da, Meng Er, Meng Lan, Meng Bao, Yu Meng ... There are many fans on social platforms, and you can call out the corresponding names when you see the pandas.
Sichuan golden monkey "Qiuqiu" and "Yang Yang" became parents for the first time this year. A month after birth, the little golden silk monkey has not been named, and even has no chance to determine its gender, because it has been held by its mother.
"Ball ball" has completely become a "baby-care maniac". When I was a "monkey dad" for the first time, "Ball Ball" was on high alert. When he saw a tourist approaching in the cage, he flew to the cage net and stomped on the net to protect his wife and children behind him.
On June 23rd, "Qiuqiu" had a strong stress reaction, and he couldn't afford to fall to the ground after running and jumping violently. On-site animal doctor's emergency rescue is invalid. After diagnosis, the cause of death of "ball ball" is related to basic cardiopulmonary diseases.
As one of the family representatives of this year's newborn animals, the "Qiuqiu" family of three has just appeared in many media news pictures. The gray little golden silk monkey is lying in its mother's arms. "Ball Ball" and "Yang Yang" are golden yellow and shine in the sun.
Beijing Zoo issued an obituary for the ball, expressing "love and missing". In their eyes, animals are colleagues, friends and relatives. Now, "Yang Yang" often sits on the perch with her child in her arms and looks around. The breeder holds her favorite crisp pear, and it has to scream a few times before turning its head.
This is a sad moment for the zoo. For the breeder Liu, the impact is even greater.
After more than two months, Liu retired. Before the age of 20, he came to work in Beijing Zoo, working in the cold storage workshop, preparing omnivores for small animals. Later, he became a good hand in raising golden monkeys and was known as the "Monkey King" of the Golden Monkey Museum.
Some golden monkeys don't bite the umbilical cord after birth. Liu cut it open with scissors, and he lifted the "ball ball" himself.
"The more you raise, the more afraid you are." When Liu was young, his master said this to him before he retired, but he didn't understand. Now, this feeling suddenly grows in Liu's heart.
He got off work by bike, rode 4 kilometers and returned to the Golden Monkey Hall. He is always worried that the door is unlocked, the window is not closed tightly and the monkey runs out. In fact, the doors and windows are tight. When the golden monkey saw him coming back, he jumped into the cage and pretended to scare him, grinning to show his "game face", which was the expression of the golden monkey when he was happy.
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After Liu's owner, Xu Yanmei, retired, she wrote a book with her husband, who is also a breeder, called Neighboring Tigers.
1980, when Xu Yanmei and Liu Zhigang got married, it was a period of tight housing. They found an empty room in Shihu Mountain of Beijing Zoo. After the application was approved, the two temporarily lived in this house separated from the tiger and beast museum.
You can clearly hear the roar and purr of the tiger. Their children were born in this house, nicknamed "Little Tiger", and the first sentence they learned was "Ah Fu, Ah Fu".
They have raised gibbons, orangutans, langurs, baboons, giant pandas and white bears 10.
At the beginning of the book, Liu Zhigang wrote that the last thing he wanted to say to animals was "I won't lie to you". Xu Yanmei is "Forget Me".
Liu's disciple said that people can be coaxed by words, but animals can't. What brilliant breeding technology and experience, sum up a sentence: "If you are good to it, it will be good to you."
Almost all the keepers in the zoo love animals very much. Lin Heng, 34, is an addict.
After graduating from Linheng University, he worked as an after-sales consultant for Jaguar and Land Rover in a shop in 4S. He sits in front of the computer every day, takes out an electronic list and asks the owner which maintenance service to choose. Many of his colleagues didn't know that Lin Heng took off his work clothes after work, quickly left the gap between luxury cars and went to the zoo as a volunteer for five years.
Lin Heng likes tapirs best. Outwardly, tapirs look like pigs with short noses. Lin Heng said that this animal was "quite primitive and interesting" and he was calm when he saw it. In winter, tapirs taste great, so tourists usually come and go in a hurry to see something new. He comes once a week, and it looks like a day.
20 16 passed the recruitment examination of Beijing zoo and became a rhinoceros keeper.
Wang was born in 1995. When he first came to work in Beijing Zoo, he specifically inquired whether the comic dialogue actor Sun Yue really kept elephants in the elephant shed.
Taking pictures of animals every day is Wang's main job. He wandered between the homes of different animals, took photos and videos of their lives and posted them on the social network account of Beijing Zoo.
When Wang photographed an elephant, he first felt its size, intelligence and flexibility.
He squatted outside the fence and photographed the mother African elephant Jingjing. Suddenly, he felt a chill on his head and turned to see Jingjing's husband "Zhuang Zhuang" hovering behind him, weighing 2 tons and more than 4 meters high, like a hill. Zhuang Zhuang blew off his hat accurately with his long nose. "This is a polite warning. They are a couple. "
After the outbreak, Beijing Zoo tried to broadcast live normally, with Wang as a live member. When he solemnly talked about popular science knowledge such as animal habits, few netizens interacted, but when he talked about the anecdotes of Beijing Zoo and the wonders of animals, netizens came to join in the fun.
For example, hippos are "stupid" and afraid of their wives, and they are often chased and bitten by their mother Jingjing. When Benben is ready to go ashore from the water, the breeder will immediately greet the tourists to "hide".
After Benben's ass came out of the water, his small tail swung like a propeller, throwing feces all over the floor. In nature, hippos mark their territory in this way. When they arrived at the zoo, they still didn't forget this habit, but some tourists occasionally "poop".
When Wang called "MengMeng" and "Lele" in the live broadcast, netizens often gave feedback in the barrage: It's the same name as my children. When you called, all the children I was watching agreed.
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Pelican is famous for "eating everything with its big mouth" and is a famous gourmet in the animal kingdom. Their mouths are almost one-third the length of their bodies, and the lower shell is connected with the skin, forming a huge laryngeal sac, which opens like a net bag.
Pelicans use this big mouth to explore the unknown. "As long as I haven't seen it, I want to eat it with my mouth." Pu, dean of Beijing Zoo Veterinary Hospital, said.
20 18 Beijing zoo opened a cultural and creative product store in front of waterfowl lake, named after "Pelican", and placed a cartoon statue of Pelican at the door of the store.
On the evening of April 15, Jin Ting, a breeder of Waterfowl Lake, found a pelican lying motionless with his mouth buried in his wings.
Social animals are easily driven away by groups after being injured, and usually hide their wounds to protect themselves. After Jin Ting approached, the pelican poked its head out-its mouth "leaked" and I don't know what new things it "explored". There is a big hole in the middle of the laryngeal sac, and it is still bleeding.
Pu and the attending doctor rushed to stop bleeding and disinfect it and transferred it to the veterinary hospital. After measurement, it was found that the wound was 22 cm long, which was the first time in the park.
"This is a serious accident. It can't eat any more, and it will miss you if you eat it. " Pu Tian Chun said that if it is in the wild, this pelican will naturally be eliminated, but this is a zoo, "human beings are responsible for animals."
Pu urgently called an animal doctor for consultation and made a surgical plan. Such a big open wound is not simply stitched. Pelican's throat sac is similar to skin tissue. After pulling open, you can see tiny blood vessels, which are as "extremely thin" as human eyelids.
The animal doctor found the surgical needle and absorbable thread for ophthalmology, and specially invited the clever female doctor Jiang Ruijie to sew the needle in the health management group of the veterinary hospital.
The fixation of animals in surgery is called Baoding. Animal rescue in the zoo or in the wild is the most difficult part, so treat animals calmly.
Animal doctors will not anesthetize animals easily, because it is difficult to master the anesthetic dose between different animals: if the dose is too large, animals may have organ damage or it is difficult to wake up again; Small dose is difficult to be effective, and it is easy to cause "patients hurt doctors".
The treatment of pelicans depends on local anesthesia and manpower. One keeper holds the pelican and the other holds its mouth. The two doctors split the laryngeal sac in two, keeping it perfectly aligned, sewing a needle and tying a knot to prevent the pelican from tearing the whole wound.
In the first operation, the breeder holding the pelican felt its heart beating very fast and worried about its stress reaction. Jiang Ruijie had 23 stitches and stopped.
After the first operation and nursing contact, the stress response of the pelican was greatly reduced. The second operation involved 9 people, and Jiang Ruijie sewed 168 stitches, which took more than 4 hours.
On June 30, after 77 days of treatment and recovery, the pelican returned to the ethnic group smoothly.
Beijing Zoo Veterinary Hospital is the first comprehensive wildlife hospital in China, where animals can see "general practice". Human doctors usually treat only one species, and doctors in veterinary hospitals have to treat nearly 500 species. Doctors divide fields according to herbivores, carnivores, omnivores, birds and amphibians and reptiles.
Like humans, animals have incurable diseases.
The orangutan chubby has been paralyzed in lower limbs since 2008. The veterinary hospital and the breeder have never given up the treatment and care for him, and the zoo has not moved him from the original site. Visitors can see "Pangpang" lying on the "bed", or lying down, or reaching out to pull the rings.
Kopka, a tourist, is printed with photos and explanations taken by Pu, introducing why this orangutan is in this state, the time of illness and the treatment method. This is the first time that Beijing Zoo has shown sick animals to the public.
Many zoos at home and abroad will move animals to places where tourists are sick and old, because tourists like to see lively animals. In some zoos, it is common for tourists to knock on railings and glass and make animals "move" by shouting.
Tian Chun said that animals also have to face diseases, aging and death. It is also a natural state that animals are born and die. I hope people can know and understand the other side of animals.
The white rhinoceros "Y97- 1" was born in 1985. I am 37 years old this year, equivalent to a 70-year-old man among humans. He worked as a breeder twice.
At its door, there is a "self-report" card: as I enter old age, my appetite, activity and mental state have declined to some extent ... I hope you will not disturb me so as not to affect my health. Thank you for your cooperation.
The only dolphin deer in the Luyuan of Beijing Zoo is the "birthday girl" in the park. The young breeder doesn't know its name and birthday.
It is lonely, not because it lives alone in the zoo-dolphin deer is listed as endangered (EN) by the World Conservation Union (UCN), as critically endangered (CRD) by the Red List of Species in China, and may have been extinct in the wild in China.
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"People's views on animals determine the development direction of zoos: food, wealth and life." This sentence was written on a book-shaped sculpture in Beijing Zoo and placed on the south side of Bear Mountain in the zoo.
Now Woong San is a new Woong San transformed from 20 14. Previously, Woong San's "pit" design was criticized by animal welfare people.
Woong San and Shi Hu Mountain were both built in 1950s, and together with Monkey Mountain, they are called the "Three Mountains" of Beijing Zoo.
Although it is called a mountain, tourists actually look down on bears, lions and tigers. The mountain is a rockery, an animal activity place between rockery and tourists, which is 5 to 6 meters lower than the guardrail in front of tourists. People look down on animals, just like the Colosseum in ancient Rome.
This can explain why Jiang Kun said that the lion Tiger Mountain in Beijing Zoo "fell into the den of the tiger" in the cross talk "A Dream in the Tiger's Mouth" of 1987.
In 2002, a vicious incident happened in Woong San where Tsinghua University students "threw bears with sulfuric acid". Five bears were badly hurt, and one of them was blind.
Zhang said that in the past, China had a poor economic foundation, and zoos all over the world borrowed from the Soviet model, so "digging holes to place and display animals" was naturally more economical and practical than the cost of building a ground stadium.
20 14 the biggest improvement of this renovation is to change the traditional "overlooking" visit to "looking up" animals through glass partitions.
Living in transformed Woong San, bears even resumed the habit of hibernation. In the winter of 20 18, the author Shihua recorded a scene in Woong San: "The hibernating brown bear suddenly raised his head, looked at the leaves and dregs on your face, then scratched his head and went to sleep again".
The interior of Shihushan has also been transformed. 20 14 Park has built a sunken visiting passage in Shihu Mountain and added a glass exhibition wall. Visitors can look up at tigers and lions. If you are lucky, you can face each other through the window when you get close.
In front of the Gorilla Museum, there is a group of sculptures called "Emancipating Gorillas". A group of gorillas carry their children to the forest. There is a sentence written here: the significance of the existence of the zoo lies in the real and complete abolition of the zoo.
If time goes on indefinitely, will the zoo disappear? Zhang believes that modern zoos have four functions, namely, entertainment, popular science education, ex-situ conservation and scientific research. With the development of people-oriented society, the "viewing and entertainment" function of the zoo may disappear, but other functions will be strengthened.
The Key Laboratory of Beijing Zoo has established a database of wildlife biological samples, which contains biological samples of rare animals, including blood, tissues, semen, swabs, feces and feathers.
This is a function that Beijing Zoo often ignores, "Save a seed and leave a hope for nature".
Before the outbreak of COVID-19, the teachers of protection education in Beijing Zoo Science Museum often played a game called "Life Net" with students.
The content of the game is simple. Every child hangs a card on his chest with Chinese characters such as rabbit, bird, snake, sun, man, river and fly written on it. The teacher took out a rope, tied it around everyone's waist and finally pulled it into a net.
If "the fly is dead", "the classmate of the fly" will kneel down, and other students will feel that the rope is tightened, "the bird is gone" and "the snake is gone" ... The more "fallen" creatures, the more tired the standing creatures are until the whole network collapses.
Zhao Xiaoli, a teacher of conservation education in the Science Museum, said that in the web of life, people are equal like other creatures.
The Science Museum keeps many animal specimens. After animals, especially rare animals, die, animal taxidermists in veterinary hospitals make specimens of their tissues, bones and fur, and send them to the Science and Technology Museum of Beijing Zoo or other scientific research units and schools for scientific research or display.
There used to be a small incinerator in Beijing Zoo, which was specially built for dead animals to cremate the leftovers. In the 1990s, the incinerator was closed, and the animals left behind were handed over to environmental protection enterprises for treatment, and finally returned to nature.
(Xia Ran and Zhao Yuli also contributed to this article)