You probably know many of the things that you can do with the hundreds of different muscles in your body. But have you ever thought about how the muscles in an animal's body are different from yours? An animal's muscles are made to do the things that are most important for its life.

Lions are hunters. They depend on their ability to catch other animals. Lions must be fast in order to catch their prey(猎物). The powerful muscles in their back legs allow them to run at the speed of more than 30 miles per hour. They can also jump a distance of more than 35 feet. The strong muscles in their front legs help them catch their prey.

Snakes also use their muscles for hunting prey and for movement, but their muscles work in very different ways than lion's do. Because snakes do not have any legs, they use their muscles to push against the ground or other objects to move themselves forward. Their muscles also allow them to eat things that seem much too large. For example, a snake may eat an egg that is larger than the width of its body. How does this happen? The snake's strong neck muscles work together to push the egg down the mouth.

The elephant's long nose has a lot of muscles. Scientists believe that the nose alone has more than 100000 muscles! This is because the elephant uses its nose much in the same way that people use their hands and fingers. Even though the nose is large, it can perform surprisingly tasks. For example, an elephant can pick up a small leaf from the ground. The nose can also be a powerful tool. An elephant can use its nose to pick up a tree by its roots or even to lift a baby elephant.

The great muscles of these animals seem pretty unbelievable. But the muscles in your body work exactly the way you need them to. After all, it might be fun to be able to jump a distance of 30 feet, but as a human being, there is just not much need of it.

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It is quite normal for us to poop（拉粑粑）. But do plants poop? They do, in fact. But plants poop differently from us. They poop to get rid of（除掉）things they can’t use or that might hurt them.

① The “April snow” is here! It’s not real snow, of course-it’s catkins (飞絮) from willows (柳树) and poplar trees (杨树) in spring. The female trees grow lots of flowers. When these flowers finish growing, they produce cotton-like seeds (种子) that spread through the air. For some people, this “snow” is not welcomed. Catkins can cause allergies (过敏), making people’s noses, eyes ,and skin uncomfortable.

② Luckily, scientists have found many ways to control catkins. Doing “gender change surgery (变性手术)” on willow and poplar trees is one of them. People cut off the branches (树枝) of female trees and replace (替换) them with branches from male trees. This cuts down the number of catkins. However, this way is slow and expensive. A skilled worker can do the “surgery” on less than ten trees a day. From 2008 to 2018,only around 1,000 trees were treated in Beijing, reported Outlook Weekly in 2022.

③Scientists in Wuxi, Jiangsu, use special injections (注射剂) to reduce the number of catkins on trees. These injections make the trees mainly use their energy to grow bigger and get more leaves, not to reproduce (繁殖) and make catkins. Xu Qinming,an expert in Wuxi, told Science and Technology Daily that this method is safe for the trees. However, the trees need to get injections every year to keep the catkin numbers under control.

④ Other than injections, the trees can take “medicine”. This medicine can be sprayed (喷洒) onto the trees before the catkins form, which can quickly reduce catkin numbers. Still, people need to be careful about how much of the medicine they use and when they use it, or they might hurt the environment.

⑤It is sure that with the development of the science and technology, there will be more convenient ways to deal with the problem.