字神帝國英語天地

今日主題：Mucus Lets Dolphins Emit Their Clicks / 使海豚發出聲音的粘液——鼻涕

洪欣老師推薦：托福聽力最好的課外教材：60-Second Science
康康精選托福會考的主題，堅持每天精聽一定會進步的哦!!

建議方法：
1. 先聽兩三遍 (不看文稿)
2. 再一句一句聽寫 (每句都要聽寫數遍，直到寫出85%以上的字)
3. 最後check文稿，看哪聽不出來，單字沒背過，還是發音不熟。
4. 堅持天天聽，就能每天進步哦。

MP3音檔 (按右鍵可下載聽)：喜歡的同學，幫忙推或按讚哦~~
http://online1.tingclass.net/voaspe/…/20160723sa_science.mp3

只有音檔怎夠，聽不懂地方，不用怕，康康幫你準備好中英文稿了：

中英文稿：
Sometimes a snout full of snot can be just what the doctor ordered. At least if you’re a dolphin. Because a new study shows that a little bit of mucus helps these marine mammals generate the rapid-fire stream of clicks they emit and use for echolocation.
醫生叮囑，至少如果你是隻海豚，鼻子裡要充滿鼻涕。因為一項新的研究表明，一點粘液可以幫助這些海洋哺乳動物產生急速連續的哢噠聲並利用回聲進行定位。

First off, let’s just get this out of the way. Dolphins do not actually sound like this. [Flipper laugh sound] That’s a made-for-TV giggle that some say is actually the doctored call of a bird: the Australian kookaburra.
首先聲明，海豚實際上並不能發出這樣的聲音。那種咯咯的笑聲出自一部電視電影，有人說實際上是用鳥叫聲來偽造的——澳大利亞笑翠鳥。

Real dolphins, like these bottlenoses, sound more like this. [Bottlenose sounds] They use their clicks, chirps and whistles to navigate, communicate and to catch their next meal. The high-frequency clicks, in particular, help Flipper and his kind locate and track fish dinners.
真正的海豚，像這些寬吻海豚，聽起來更像這樣。它們通過發出的哢噠聲、啾啾聲、口哨聲來進行導航、通訊和捕食。尤其是高頻的哢噠聲，可以幫助Flipper和它的同類進行定位，追蹤晚餐。

Dolphins make these sounds by forcing air through a nasal passage just beneath the blowhole. In this nasal region are liplike flaps of tissue called dorsal bursae that vibrate and collide to produce dolphin talk.
海豚們迫使空氣通過通氣孔下方的鼻道，從而發出這種聲音。鼻區有唇形片狀瓣膜，被稱為背黏液囊，通過振動和碰撞使海豚能夠“講話”。

Now, a team of researchers has created a simplified model that can reproduce this characteristic dolphin chatter. And they found that the secret ingredient is snot.
現在，一組研究人員已經建立了一個簡化的模型，可以重現海豚語這一特徵。並且他們發現的秘密成分是鼻涕。

While looking through the literature, oceanographer Aaron Thode stumbled across a model that represented vocal cords as masses connected by springs—which store and release energy—and dampers, which dissipate that energy. This model successfully replicated the essential characteristics of the system, like the frequency of vocal cord vibration.
在看文獻時，海洋學家Aaron Thode偶然發現了一個模型：將聲帶看作由彈簧相連的集塊——儲藏和釋放能量以及消散能量的阻尼器。這個模型很好地契合了發聲系統的基本特徵，如聲帶振動的頻率。

So Thode enlisted his father Lester, a retired nuclear physicist from Los Alamos National Lab, to help him fit the model to a dolphin’s nasal anatomy. When the Thodes compared the simulated sounds produced by their model to a recording of actual dolphins, they found that the model mimicked both the loud thump and extended ring that are part of the natural click.
因此，Thode讓他的父親加入其中，説明他使這個模型與海豚的鼻部解剖相符合。他的父親是洛斯阿拉莫斯國家實驗室退休的核子物理學家。當他們將模型產生的類比聲音與海豚真實錄音進行比較時，他們發現，模型類比的撞擊聲和回聲，是海豚原哢噠聲的一部分。

The initial thud comes from when those dorsal bursae collide. And the reverberation results from the vibrations that linger when the tissues pull apart. But Thode the younger says the bursae have to be somewhat sticky for the clapping together and snapping apart to produce a noise with the correct loudness and pitch. That stickiness comes courtesy of the mucus. Thode vocalized the results at the meeting of the Acoustical Society in Salt Lake City.
最初的聲音來自背部黏液囊的碰撞。而持續的混響來源於組織分離時產生的振動。不過 Thode認為，黏液囊必須要有足夠的粘性，一下靠攏又分開，才能產生這種聲音並達到正確的音量和音高。這種粘性來自粘液，Thode在鹽湖城的聲學學會上發佈了該研究成果。

The match between the simulated sounds and the real deal is encouraging, and the Thodes plan to keep up their collaboration to refine their model. “Yeah, I guess some fathers and sons bond over football, but my dad and I, I guess we bonded over differential equations and writing this paper.”
模擬聲與海豚原聲的匹配度激勵著人們，Thodes打算繼續協作，完善他們的模型。“是的，我認為某些父子的親情因為足球而更加深厚，而我和我父親，我想是因為微分方程和撰寫這篇論文。”