97 Animal Ears-Mid

Animal Ears FOCUS Question How do the ears of different animals allow them to hear sounds?

动物耳朵焦点问题不同动物的耳朵是如何让它们听到声音的?

Ears for Hearing What kinds of sounds do you hear in your everyday life? Perhaps your phone plays a song when a friend calls. You may listen to your favorite music on a computer. A bell likely marks the beginning and end of each school day. Your ears allow you to hear all the sounds that are important to you. Animals have different kinds of ears for hearing sounds that are important to them. How Sound Travels Sound is produced when tiny particles, called molecules, move back and forth, or vibrate Vibrating molecules cause the molecules next to them to vibrate, which is how sound travels. Sound can travel through gases, such as air, and also through liquids and solids.

听力的耳朵你在日常生活中听到哪些声音? 也许当朋友打来电话时，你的手机会播放一首歌。 你可以在电脑上听你最喜欢的音乐。 铃声可能标志着每一天的开始和结束。 你的耳朵能让你听到所有对你重要的声音。 动物有不同种类的耳朵来听对它们很重要的声音。 声音是如何传播的当被称为分子的微小粒子来回移动或振动时，声音就产生了。振动的分子引起它们旁边的分子振动，这就是声音传播的方式。 声音可以在气体中传播，比如空气，也可以在液体和固体中传播。

Let Your Ears Stick Out Humans and other mammals such as cats, dogs, and bats have similar ears. The outer ears "catch" sound vibrations and send them to the eardrums. The eardrums then vibrate. The vibrations travel through three tiny bones in the middle ears. and then to the inner ears The cochleas (KOKE-lee-uz) change the vibrations into nerve impulses that are sent to the brain, which recognizes the sound. Most animals have two ears, one on each side of the body. Depending on where a sound is coming from, one ear hears it before the other. This feature helps animals locate sounds.

人类和猫、狗、蝙蝠等哺乳动物都有类似的耳朵。 外耳“捕捉”声音振动并将其发送到耳膜。 耳膜随之振动。 振动通过中耳的三根小骨头传播。 耳蜗(KOKE-lee-uz)将振动转化为神经冲动，并传送到大脑，从而识别声音。 大多数动物都有两只耳朵，身体两侧各有一只。 根据声音的来源，一只耳朵比另一只耳朵先听到。 这个功能可以帮助动物定位声音。

Ocean Vibrations Whales are mammals, too. Because they live in the ocean, their ears are built differently. In water, a human's entire skull vibrates when sound hits it. Both ears vibrate and hear sound at the same time. As a result, humans have a hard time locating sounds underwater. But in whales the bones of the middle and inner ears are outside the skull, so each ear vibrates separately in response to sound. One ear receives a sound before the other, and the sound is louder on that side. For this reason, whales know where a sound is coming from, even in the water. HOW WHALES HEAR 1. Sound vibrations from a fish travel toward a whale. 2. The vibrations enter the whale's lower jaw and then travel to the auditory bulla. 3. Nerve signals travel from the auditory bulla to the brain.

鲸鱼也是哺乳动物。 因为它们生活在海洋里，所以它们的耳朵构造不同。 在水中，人的整个头骨在听到声音时都会震动。 两只耳朵同时振动和听到声音。 因此，人类很难定位水下的声音。 但在鲸鱼中，中耳和内耳的骨头都在头骨外，所以每只耳朵都会对声音做出反应。 一只耳朵比另一只耳朵先接收到声音，而且那一边的声音更大。 因此，鲸鱼知道声音来自哪里，即使是在水里。 鲸鱼的听觉鱼发出的声音振动会向鲸鱼传播。 2. 振动进入鲸鱼的下颌，然后传播到听觉泡。 3.神经信号从听觉大泡传递到大脑。

Floating Fish Ears Similar to a human's skull, a fish's entire body vibrates in water. So how can a fish detect sounds and tell where they are coming from? Each inner ear has three hard, floating bones. These bones are much heavier than the rest of the fish, so they move much more slowly in response to sound. The slower moving bones cause tiny hairlike structures in the inner ears to move. The fish's brain understands those movements as sound. Many fish have a swim bladder—an air-filled sac that helps them float in water. It is sensitive to sound waves. Fish that have inner ears close to their swim bladder hear better than other fish do. Fish that don't have swim bladders, such as sharks, can't hear as well.

漂浮的鱼耳朵与人类的头骨相似，鱼的整个身体在水中会振动。 那么，鱼是如何探测声音并辨别声音来源的呢? 每个内耳都有三块坚硬的浮动骨头。 这些骨头比鱼的其他部位要重得多，所以它们对声音的反应要慢得多。 移动较慢的骨头导致内耳中的微小毛发状结构移动。 鱼的大脑把这些动作理解为声音。 许多鱼都有一个鳔——一个充满空气的囊，帮助它们在水中漂浮。 它对声波很敏感。 内耳靠近鱼鳔的鱼比其他鱼听得更清楚。 没有鱼鳔的鱼，比如鲨鱼，也听不到声音。

Hearing with Echoes Bats use a process called echolocation to find prey. They send out clicks and listen for returning echoes to find moths and other insects to eat. The wrinkles in bats outer ears help them receive echoes and other sounds. The clicks that bats make are loud and high-pitched. Luckily, bats have a trick to avoid being deafened by their own clicks. A muscle makes the three tiny bones in the middle ear pull apart. The sound vibrations from the click are blocked. Then the muscle relaxes and the bones touch again—just in time to vibrate and let the bat hear the echoes! Try This Plug your ears as you shout "Echo!" Then quickly unplug them to hear your echo. You're hearing like a bat!

蝙蝠通过一种叫做回声定位的过程来寻找猎物。 它们发出咔哒声，并倾听回声，寻找飞蛾和其他昆虫来吃。 蝙蝠外耳上的皱纹帮助它们接收回声和其他声音。 蝙蝠发出的咔哒声又响又高。 幸运的是，蝙蝠有一种技巧，可以避免被自己的咔哒声震聋。 肌肉使中耳的三块小骨头分开。 咔哒声的震动被挡住了。 然后肌肉放松，骨头再次接触——刚好及时震动，让蝙蝠听到回声!当你喊“Echo!”时，把耳朵塞住。然后迅速拔掉插头，听到你的回声。 你的声音跟蝙蝠一样!