Wonderful animals in the world

Star-nosed mole: Something once thought to be an alien spy.

brief introduction

If you want to choose a star in the animal kingdom, the star-nosed mole will definitely win with its grotesque nose. Its nose, like octopus tentacles, is very unique. The famous physicist Wheeler once said, "No matter where you are, you should explore the strangest things and explore them." Of course, it's hard to imagine an animal stranger than a star-nosed mole.

Characteristics of nose

It's more like a creature that appears from a flying saucer and greets the curious representatives of the earth people. Its nose is surrounded by 22 fleshy appendages. When it shuttles between its surroundings, its nose is often blurred by rapid vibration.

Composition and evolution

Coupled with the forelimbs with giant claws, you encounter an exciting and incomprehensible biological mystery. How did this creature evolve? What's that star? How does it work and what is it used for? For this unusual mammal, these are the puzzles I want to solve. Results The star-nosed mole not only has a funny face, but also has a quite specialized brain, which may help to answer the long-standing question about the composition and evolution of mammalian nervous system.

Readers may be relieved to learn that the star-nosed mole is a small animal, and can only tilt weighing scale's pointer to 50g, which is about twice that of a mouse. They live in shallow tunnels in wetlands, all over the northeastern United States and eastern Canada, and their hunting environment covers underground and underwater. Like about 30 other species of moles, the star-nosed mole belongs to an insect-eater, a mammal. This creature has a very fast metabolism and is always hungry, so this small star-nosed mole with a huge appetite will surely find enough prey to spend the cold northern winter.

Predatory characteristics

Like other moles, it looks for earthworms in the soil; However, it will also feed on various small invertebrates and insect larvae in nutrient-rich silt and rotten leaves in wetland habitats, and will also dive to the mud bottom of ponds and streams to find prey. Looking for prey is the time for Starnose to play. The star nose is not a part of the olfactory system responsible for the sense of smell, nor is it the third hand used to catch food, but an extremely sensitive tactile organ.

Xinjiang giant salamander, also known as giant salamander, is the only tailed amphibian in Xinjiang at present. It lives in Wenquan County, Xinjiang, and only lives in the shallow waters of alpine spring streams and lakes at an altitude of 2 100-3200m. It is a relic animal that survived when Tianshan Mountain and Alatao Mountain rose from the ground, 3-4 years ago. Xinjiang newt's habitat is extremely narrow. At present, it only exists in Alatao Mountain and Tianshan Mountain bordering Kazakhstan in the west of Wenquan County, Xinjiang, and the number is rare. The number of individuals in Jiemaigou and Sulubie town is about 3500-4000. As an endangered animal, Xinjiang giant salamander has long been included in the international joint red book on nature and natural resources protection. 1998, the giant salamander in Xinjiang was listed in the Red Book of Endangered Animals in China, with the endangered level of "extremely endangered", which became a precious germplasm resource in China and has been listed in the national first-class protected animals.

1866, Russian zoologist kessel discovered a lizard-like animal about 20 cm long, with thick fingers and smooth body. This is something he has never seen before. He thought it was a great discovery, so he took the animal back to the laboratory and described its species.

In the following 100 years, Chinese and foreign experts visited Tianshan Mountain and Alatao Mountain in Xinjiang and Kazakhstan for many times, trying to find this mysterious animal. After repeated failures, people came to the conclusion that the animals that kessel had seen were extinct and no one would ever see them again.

1989 In September, students from Wenquan County, Department of Biology, Xinjiang Normal University brought a four-legged snake from home. Wang Xiuling, a biology teacher, suddenly remembered the guy who told his students all day that the Russians had discovered it before 100 years, but no one had seen it. The next day, she and several colleagues went straight to Wenquan County ...1September 6, 989, 23 years have passed since kessel last saw this animal. 1990 Found the second habitat of giant salamander.

The giant salamander in Xinjiang is only distributed in Alatao Mountain and Tianshan Mountain, which are the boundary mountains between China, Xinjiang and Kazakhstan. The habitat is extremely narrow, with a central area of about 500 square kilometers, which is rare in the animal kingdom.

Scientists found giant salamander fossils in Junggar basin and Urumqi, Xinjiang, indicating that giant salamander was widely distributed in the vast waters of Junggar basin more than 200 million years ago at the peak of amphibians. And a group of lucky people, with the uplift of Tianshan Mountain, rose to the ridge more than 2000 meters above sea level, just where countless springs gushed out, providing the most basic conditions for the survival of python. Fortunately, this spring comes once in a billion years.

According to experts, Xinjiang's salamander is a relic animal and the only tailed amphibian in Xinjiang. It has important academic research value in the classification and systematic evolution of Siluridae. It has been listed in the red book of the International Union for Conservation of Nature and Natural Resources (IYCN) and the red book of the former Soviet Union.

Qu of Sun Yat-sen University and papers published by Xinjiang Normal University hold that the giant salamander in Xinjiang is an ancient animal with a history of nearly 300 million years. The DNA extraction and analysis of northern salamander show that it has high homology with sauropod in fish. sauropod is considered as an ancient fish that appeared in fresh water 400 million years ago and is the direct ancestor of amphibians. This shows that the divergence between the northern salamander and barracuda in Xinjiang occurred not long ago, which may be the representative of the earliest amphibians who climbed onto the land after barracuda. Therefore, it should be the direct or indirect ancestor of terrestrial life. How amazing and incredible it is that the clues of life evolution 300 million years ago have become so clear.

Due to the harsh ecological environment and lack of food, especially in recent years, human disturbance and destruction, livestock trampling and illegal capture, Xinjiang northern salamander is becoming increasingly endangered, and its population has dropped sharply. According to an expert survey on1September 6, 1989, there are about 600 salamanders in Xinjiang, with a population density of 0. 12. There were only about 200 salamanders in July, 1990. 1993 is about 150, 1996 is less than 100, and the population density is 0.02.

Platypus habitat

The most primitive and peculiar animal among the living mammals. It is only distributed between Cape York in eastern Australia and South Australia, and also inhabits Tasmania.

Characteristics of platypus

The platypus is one of the strangest monotremes in Australia. The so-called monotremes refers to an animal between reptiles and mammals. Although more advanced than reptiles, it has not yet evolved into mammals. The similarity between the two is that they both breathe with their lungs, have long hair and are full of blood; Monopore animals reproduce by laying eggs, so they retain the important characteristics of reptiles.

Everyone who has seen platypus says it looks really strange. When British immigrants entered Australia and found platypus, they exclaimed that it was an "incredible animal". The platypus is about 40 cm long and covered with soft brown thick short hair. Compared with the echidna, its skull is smaller and its brain is hemispherical and smooth. The limbs are short, the five toes are hooked, and there are membranous webs between the toes, which are shaped like duck feet. When walking or digging, the web is folded in the palm of your hand in the opposite direction. The snout is flat and shaped like a duckbill. There are wide horny gums in the mouth, but there are no teeth. The tail is large and flat, accounting for 1/4 of the body length. It acts as a rudder when swimming in the water.

Male platypus has thorns on its hind feet. It stores poisonous juice, which will hurt people when sprayed, just like snake venom. If a person is stabbed by a poisonous distance, it will cause severe pain and it will take several months to recover. This is its amulet. The female platypus is also poisonous at birth, but it disappears when it grows to 30 cm. Platypus is an amphibian and usually likes to make holes in the water. When in the water, its eyes, ears and nose are closed, and it only feeds on shellfish by perception. It eats a lot, and consumes food equivalent to its own weight every day.

Although mothers also secrete milk to feed their young, they are not viviparous but oviparous. That is, the mother bird lays eggs and hatches by the temperature of the mother bird like a bird. The mother beast has no breasts and nipples, but secretes milk on both sides of the abdomen, and the cubs lie on the mother beast's abdomen and lick.

Larvae has teeth, but adult gums have no teeth, instead, they are horny plates that can grow continuously. Many raised transverse ridges are formed on the occlusal surface in front of the board, which are used to crush the shells of mollusks such as shellfish and snails, or to chop up other foods. The horny plate at the back is flat, and the flat uvula opposite to the plate has an auxiliary "chewing" effect.

The platypus in Australia is a very special mammal monotremes endemic to Australia. Its mouth and feet are like ducks, and its tail is like beavers. It is one of only three kinds of mammals that lay eggs in the world (the other are the echidna and the bagged hedgehog in Australia). The platypus has no nipples, but it has a small bag on its stomach, which can secrete milk. The platypus grows up by adding milk.

The adult platypus is 40-50 cm long, and its weight is between 700-1600g for females and between1000-2,400g for males.

Living habits

Platypus lives on the banks of rivers and streams. It spends most of its time in the water. Its fur is oily and can keep its body warm in cold water. When swimming in the water, it closes its eyes and looks for food at the bottom of the river bed by means of electrical signals and tactile sensitive duckbill. It feeds on mollusks and small fish and shrimp.

The platypus breeds in a long tunnel dug on its shore. It can lay up to three eggs at a time. After six months, the platypus will learn to live independently and feed at the bottom of the river bed.

The platypus pursues mating in the water, and its eggs are like turtle eggs. After hatching, platypus can only go out for food by breastfeeding for 4 months. Platypus is a nocturnal animal. They are used to sleeping during the day and exercising at night.

Platypus can dive, often building its nest on the bank of swamps or rivers, and its holes are underwater, including mountain streams, stagnant water or dirty rivers, lakes and ponds. It dug a hole on the shore as a shelter, and the cave was connected with the adjacent waters. It's an underwater forager. It will dive into the water when foraging, and each time it has a diving period of about one minute. It explores shellfish, worms, crustaceans, insect larvae, other animal foods and some plants in the mud with its mouth. The platypus, which is distributed in southern Australia and Tasmania, is the most primitive mammal in existence, and it is an evolutionary link to form higher mammals, which has great scientific research value in animal evolution.

Inactive or hibernating in winter. The female digs a cave equivalent to 16 meters long and lays her eggs in a nest made of wet aquatic plants, sometimes laying three eggs at a time. Eggs are smaller than sparrow eggs and stick to each other. During the incubation period, the holes are blocked and the hatched larvae are not fully developed. The platypus has neither a pouch nor nipples, and the mammary gland bundle is directly opened in the abdominal breast area. The cubs suck milk from the breast area with a retractable tongue for about five months.

Academic significance

The platypus is of great academic significance. Hundreds of millions of years have passed, and it has neither become extinct nor evolved much. Has been wandering in the "transitional stage". It's really strange and mysterious, full of mystery. This kind of animal, which is only produced in Australia in the world, was once on the verge of extinction due to the pursuit of specimens and precious fur for many years. Because of its particularity and scarcity, it has been listed as an international protected animal. The Australian government has promulgated protection regulations.

A nerve-racking platypus

There are only two kinds of people in the world who don't make mistakes: unborn children and dead people. Today, I'm afraid everyone will say that there is no perfect person who doesn't make mistakes. However, in previous years, this statement was absolutely unacceptable.

This starts with a special animal I saw in Australia.

It was an early spring morning, and I saw a very strange animal called platypus in Tasmania, southern Australia. It is not only a mammal, but also lays eggs; Such as birds and reptiles.

It is said that in 1880, a platypus specimen was sent to London from the then British colony Australia, which made famous British biologists furious. They asserted that the specimen was made up of several different animals and threatened to find out who dared to play such a prank. Engels is one of the auctioneers.

According to traditional ideas, mammals must be viviparous and cannot lay eggs. Engels, the revolutionary mentor, once adhered to this understanding, and later changed his understanding before the test of practice, and used it as a lesson to remind others, and used it as a lesson to set an example for people to attach importance to science and seek truth from facts. Engels wrote in a letter to Kang Schmidt in 1895: "I saw the eggs of platypus in Manchester. I laughed at the stupid idea that mammals can lay eggs, which was arrogant and ignorant, but now it has been confirmed! So, I hope you won't make the same mistake again! "

The platypus has a wide and flat mouth, a short and blunt thick tail and a pair of webbed feet. At first glance, it looks like the same duck. Moreover, its beautiful and soft gray fluff can be compared with our country's specialty otter.

The platypus is really strange. Call it an animal, but it breeds offspring by laying eggs; It is called a reptile, but its hatched offspring are all breastfed. It's neither fish nor fowl. We know that small animals hatched from eggs generally do not eat milk, such as chickens, ducks, birds and snakes; But most mammals are viviparous and don't lay eggs, such as cats, dogs, pigs and sheep.

Because platypus lays eggs and feeds on milk, biologists have a headache and don't know which animal to include it in. After years of argument, we finally have to classify platypus as a mammal based on hair and milk, and call it an "oviparous mammal". Because only mammals in the world have round hair (birds' feathers are flat) and secrete real milk, and platypus has both characteristics.

The male platypus is more than 50 centimeters long and the female is slightly smaller. Their legs are short and strong, and each leg has five toes. The toe ends with hooked claws, and webbed toes are convenient for swimming. Its hairy tail acts as a "rudder" when swimming. Its eyes are small, there is no ear shell, and its clavicle and coracoid bone are well developed, much like a bird.

Platypus is used to sleeping during the day and coming out for food at night. Frogs, earthworms and insects are all its food. It has a strong digestive function. A platypus weighs less than one kilogram, but it can eat food equivalent to its own weight in one day.

The platypus always burrows by the river. This hole has two exits, one leads to the water and the other leads to the grass on the land. Their ability to dig holes with their claws is very high. Even on the hard river bank, they can dig a hole one meter deep in ten minutes. Some caves are tens of meters long and have spacious "bedrooms" where they can lay eggs at any time. The bedroom is covered with leaves, reeds and other hay, just like a comfortable "bed"

The female platypus lays two eggs at a time, white and translucent, with a layer of colloid on the shell. The female platypus put the egg between her tail and abdomen, and then curled up around the egg. Two weeks later, the little beast came out of its shell, but it was invisible, hairless and unable to eat. It was all fed by its mother.

Compared with reptiles, platypus is obviously a higher animal, because although it lays eggs, it is a mammal. But among mammals, it is the lowest. It uses the same organ to lay eggs and excrete feces and urine, so it is also called monophyletic. Australia is home to the only single-celled animal in the world. Besides platypus, there is another species called echidna.

The world is big, and there is no wonder. There are still many mysteries to be explored in biology!

Research: Theoretically, from the genetic point of view, the most peculiar gene of platypus is the 10 chromosome, which is responsible for sex. Platypus may have 25 different sexes, although this phenomenon has not actually happened.