Children are the future of the country. It is very necessary to educate them scientifically and correctly from an early age. One hundred thousand why introduced a large amount of scientific knowledge in simple, vivid, popular and accurate words and in the form of answers. Here are the 100000 whys I recommend carefully: why do pandas love climbing trees? For reference only, welcome to read!
100000 reasons: why do pandas love climbing trees
Giant pandas are good at climbing trees and playing. Climbing a tree is usually a way for the weak to avoid the strong when approaching the proposal period, or avoiding danger, or meeting each other. Pandas sometimes go down to the valley and string into villages or houses. They use pots, pans and barrels, especially round utensils, as toys and discard them in the mountains after playing. Sometimes they are kind to domestic animals such as sheep and pigs, and eat and live together.
Giant pandas spend half of their time eating every day, and most of the rest is in sleep. In the wild, giant pandas sleep for 2-4 hours in the middle of every two meals. Lying on their back, lying on their sides, lying on their stomach, stretching or curling up are their preferred sleeping methods. In the zoo, the keepers feed them regularly twice a day, so pandas spend the rest of their time resting. Even when sleeping, giant pandas look cute. They are very flexible and can put their heavy bodies in various postures. My favorite position is to put your legs on a tree and cover your eyes with your hands.
The most lovely features of a giant panda are its fat body and its slow walking style. This is because they live in an environment with plenty of food, no natural enemies and no need to move quickly. However, it is this slow movement that enables it to conserve energy to adapt to low-energy food. They sometimes climb trees to detect situations, escape intruders, or take naps.
Under normal circumstances, giant pandas are always very docile. When meeting people for the first time, they often use their forepaws to cover their faces or lower their heads without revealing their true faces. They rarely attack other animals or people on their own initiative. When they meet by chance in the wild, they always avoid it. But once she becomes a mother, her baby is sacred and inviolable. Even caring and visiting will annoy her mother, open her teeth and claws, and use her hands and feet. Sometimes they also like to make some modifications and other fitness activities. You can straighten your body like a cat, stretch your front and lift your back to make your body stretch flexibly, or yawn with your forelimbs when you wake up. If you get wet or cross the river, you can shake off the water like a dog.
How do Saber Toothed tigers prey on their prey
The unique head shape of saber toothed tiger makes people can see the difference between saber toothed tiger and living tiger at a glance, but they have significant similarities. In fact, saber toothed tiger represents an extinct type of cats. It was very prosperous in a certain geological historical period and did not die out until the end of the Pleistocene about 10000 years ago. The tiger is the living representative of cats. Saber toothed tiger is about the same size as a living lion or leopard, but different from other cats, saber toothed tiger's upper canine teeth are long and flat, and the cross section is rhombic, like two long swords, which is also the source of the word "saber teeth"; The upper canine of other cats has a circular section, like an awl. The longest saber tooth found is 26 cm from the root to the crown, and the shortest is 20 cm long. The front and back edges of saber teeth form sharp edge ridges. Some saber teeth also have developed serrations. Such teeth can not be found in living animals.
How does saber toothed tiger use its dagger like upper canine teeth to kill its prey? This puzzle has been puzzling paleontologists. Almost all conceivable ways of using saber teeth of saber toothed tiger have been hypothesized.
Some people believe that the saber teeth have the opening function of a can knife, which is suitable for catching and killing animals covered with armor, such as the carved toothed beast in South America; Some people think that saber teeth can be used to help climb trees like ice picks used in mountaineering; Others believe that saber teeth have similar functions with walrus teeth, and Saber Toothed tigers are likely to adapt to aquatic life; Some people believe that saber teeth can stab prey by closing their jaws and jaws tightly; Others believe that saber teeth can be used to cut animal flesh. However, it has been suggested that huge saber teeth are not conducive to their own eating, because large meat pieces will not enter the mouth through the gap between the two upper canine teeth. Saber Toothed tigers are extinct because they can't get enough food. Among all kinds of hypotheses, "assassination theory" and "tear theory" have the most supporters.
"Stabbing theory" holds that the saber teeth have the function of puncture and are an effective weapon to stab prey. Those who hold this hypothesis have analyzed the skull structure of Saber Toothed tigers in detail and found that they can use great force to make the upper canine teeth pierce downward. The jaw opening angle of saber toothed tiger is much larger than that of living cats, up to 150 ° or even 180 °, which can be compared with the open mouth of snake. Therefore, the saber toothed tiger can complete the perfect piercing action and make effective use of the kinetic energy generated when it pours on its prey.
Those who hold the "tear theory" believe that the saber teeth are too long, too flat, and too curved, which is very easy to break. Therefore, the saber toothed tiger should not adopt the highly dangerous behavior of stabbing. In fact, Saber Toothed tigers should fight their prey and gradually control their prey before using canine teeth. In this case, saber toothed tiger can better find the precise penetration point, and try to avoid the fracture of upper canine teeth caused by fierce resistance of prey. Therefore, controlling prey plays an important role in the safety of saber toothed tiger, and the strong forelimb bones and retractable claws of saber toothed tiger are the basis of this control process. In this regard, saber toothed tiger's behavior is consistent with that of living cats, that is, it uses its forelimbs and claws to grasp its prey so that it can't twist and break free. The furrow ridge developed on the surface of the saber toothed tiger's upper palate shows that it first sucks the blood of its prey, and then cuts and tears the flesh of its prey backward.
Is arowana the ancestor of Golden Arowana
There is an extinct fish called arowana, which sounds very close to the Golden Arowana. What is their relationship with the Golden Arowana?
This kind of fish was first translated as "lizard fish" by researchers, but later changed to the resounding name "arowana" because it didn't sound well. The arowana has a very long pointed mouth and a slender body in a streamlined shape. At first glance, it is really similar to reptiles, so it is named. Their length ranges from less than 10 cm to more than 1 meter. Fossils are distributed all over the world. The earliest arowana fossils were found in the Late Permian strata of Changxing, Zhejiang, China. The Triassic is the period of great development of arowana. So far, there are 3 genera and nearly 40 species of arowana.
Although there is only one word difference between arowana and Golden Arowana, arowana is not the ancestor of Golden Arowana. They belong to two distinct groups of radial fin fish.
Arowana is a relatively primitive radial fin fish, which is closest to the evolution of the present cartilaginous hard scale fish sturgeon. In recent years, the diversity of arowanas found in the Middle Triassic strata in Yunnan, Guizhou and other places in China is very high. The fossils of arowanas found in the same place can be divided into several different genera. This is rare in fish fossils, but it also shows that there were diversified ecological adaptation modes of arowana at that time. Although it narrowly escaped the extinction of biological clusters at the end of the Permian, all arowanas died out in the early Jurassic about 200 million years ago.
Now, the Golden Arowana seen in the ornamental fish market is a representative of the true bone fish, bony tongue fish, which is more advanced than the cartilage hard scale fish. Bony tongue fish is a remnant of ancient freshwater fish, named for its bony teeth on its tongue. The earliest bony tongue fish first appeared more than 100 million years ago, and then distributed all over the world. Nowadays, bony tongue fish are mainly distributed in the tropics. Because its side is flat like a belt, it is also called waist hairtail locally.