What Is Marsupialization?

Marsupials are notochords, mammals, subzoozoans, possums, and a class of animals that are not characterized by a fully developed placenta. They are born prematurely, and premature babies will stay in the mother s nursery bag and suck milk. Big. This type of animal is named after its pocket-like childcare bag. A childcare bag is a layer of skin that covers the nipples. Such animals that survive today include kangaroos, koalas, wombats, wombats.

Marsupials dominate the animals in Australia. These animals have a skin fold in the abdomen, and they can hold a baby inside. Animals with brooding bags are also found in the Americas, but are more widely distributed in Australia.

The red kangaroo is the largest marsupial in size today. It has become one of Australia's symbols and even appears on the country's national emblem. Tall and strong female kangaroos have small babies that can't even take care of themselves. It grabbed the mother's dense hair, crawled hard into the brooding bag, and held her nipple firmly. They spend about half a year in the brooding bags, during which time they have been breastfeeding and ready to travel to the outside world.

Marsupials are found in all natural areas of Australia, from tropical forests to deserts. They include both carnivores, insectivores, and even herbivores ^[1]

There are about 237 species of marsupials in existence, which are divided into more than ten families including possum family, marretaceae, marsupials, plovers, new kangaroos, marsupaceae, wombats, and kangaroos. Among them, the distribution of New Kangarooidae is limited to parts of South America, and the Posidae family is located in South and North America. The rest are distributed in Oceania or a small number of Southeast Asian islands.

Among marsupials, the kangaroo is the most famous and cute rarity, and its image appears on the national emblem of Australia, so that it almost becomes a synonym of Australia. There is another interesting story about the origin of its English name. It is said that in the 18th century, a British navigator led a convoy to Oceania for the first time. When they saw this kind of monster with short front legs and long hind legs, they were very surprised and asked the local indigenous people how to call it A kind of animal, the native answered: "kangarooo". As a result, Kangaroo became the English name for Kangaroo, and it is still used. But people later figured out that "Kangaroo" means "don't know" in local Turkish.

For most mammals, when pregnant, the fetus lives in the female's belly, and the nutrients needed are provided by the placenta that connects the fetus to the mother. The fetus will not give birth until the organs of the fetus are well developed. However, in the mammalian kingdom, there is a very special family, which is characterized by premature birth. Why do they have premature births? How do premature children survive? Here we come to know this particular family-the marsupial family.

Marsupial mammals appeared in the early Cretaceous. During long-term evolution, they did not have the structure of the placenta, so the fetus did not get enough nutrition in the stomach. In order to continue their race, they chose to give birth to their children early, use milk to provide food to the children in vitro, and use the milk that is rich in nutrition to make up for their innate deficiency. After the children are born, they will fall directly into the mother's bag. The bag was like a piece of cloth covering the mother's nipple. Once the child is born, he will look for nipple sucking by himself. When the child grows up to face the outside world by himself, it will drill out of the bag and go to the world by itself.

Among the existing mammals, marsupials are considered "heterogeneous," but in the early Cretaceous they were evenly divided with placental mammals. At that time marsupials were found all over the world and were an ancient group of mammals. However, with the change of geology, placental animals became stronger because they quickly adapted to this change. Marsupials gradually lost their competition. Many marsupials became predators of carnivores. Marsupials are extinct on continents such as Asia, Europe and Africa. Fortunately, Oceania has been separated from other continents before, and it exists in isolation between the Pacific and Indian Oceans. Carnivorous higher mammals have not invaded this continent, and the climate and environment have not changed much. In the end, marsupials are here. "Xanaduyuan" survives. Oceania is therefore called! 'Museum of Living Silkworms'. In addition to Oceania, there are also marsupials in a small number of areas in South America, about 70 species. How did marsupials in South America originate? For this reason, scientists have not found the best answer.

As the world exchanges become more frequent, many species have invaded areas where marsupials live, threatening their survival. In order to protect these magical objects, the Helm of Puppet Helmets: Action, make its own contribution to protect it ^[2]

Since the Europeans immigrated to Australia in 1788, many new animals have been introduced. The original living conditions of many marsupials have been destroyed. Due to various natural and social factors, 6 small kangaroos have become extinct.

Due to the intensified impact of human economic activities, it has brought many adverse effects on the survival of marsupials in the future. So far, about 17 species of marsupials have been listed in Appendix I of the Convention on International Trade in Endangered Species of Wild Fauna and Flora. Included in Appendix II. If the living marsupials are not strictly protected, this group that is very unique in the evolution of mammals and has important academic significance will eventually decrease or become extinct as human economic activities increase further.