新东方在线网络课堂 托福 新东方在线 > 托福 > 托福精选 > 正文

科学美国人60秒:海豚通过鼻涕粘液发声-托福听力下载

2016-11-22 14:28:06 来源:科学美国人60秒托福资料下载

点击查看>>科学美国人60秒音频:海豚通过鼻涕粘液发声

  科学美国人60秒中英文翻译:海豚通过鼻涕粘液发声

  科学美国人60秒英文文本

  This is Scientific American — 60-Second Science. I'm Karen Hopkin.

  Got a minute?

  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.

  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.

  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.

  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.

  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.

  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.

  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. That's the sound, but slowed down to make it audible to our ears.

  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.

  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."

  Thanks for listening for Scientific American — 60-Second Science Science. I'm Karen Hopkin.

  中文翻译请点击下一页

本文关键字: 科学美国人60秒 科学60秒下载 托福听力

为你特别匹配的托福超值课程,快速提分先人一步!
  • 大学生旗舰直达冲100分

    【知心托福】大学生旗舰直达冲100分

    适合人群:托福目标分数100!!!

    课程特色:推送补充相应知识点,有效提升学习效率。

    查看详情
  • 【知心托福】大学生旗舰直达冲90分

    【知心托福】大学生旗舰直达冲90分

    适合人群:托福目标分数90!!!

    课程特色:推送补充相应知识点,有效提升学习效率。

    查看详情
  • 【21天冲分】 21天直冲托福100+

    【21天冲分】 托福2018年6月临考急训25人班

    适合人群:参加过托福考试或基础段的学习,距离最新考试仅剩1个月时间,急需短期内快速高效冲分的考生。

    特点:全科直播24小时

    查看详情
  • TOEFL6月早练团

    【早练团】TOEFL6月早练团

    课程特色:高能学习的正确打开方式,早练早提分!

    课时:28课时(每天0.5小时,5月共上课28天)

    查看详情
  • 大学生旗舰直达班 (冲110分)

    【知心托福】大学生旗舰直达班 (冲110分)

    适合人群:托福目标分数110分!

    课时:343

    查看详情

课程试听换一换

  • 知心托福 大学生旗舰直达班 (冲110分)

    ¥8280

  • 知心托福 直达班(冲110分)

    ¥4380

  • 知心托福 精品直达班(冲110分)

    ¥5880

  • 知心托福 大学生旗舰直达班 (冲100分)

    ¥7980

  • TOEFL 6月早练团-单日“听力团”+双日...

    ¥28

  • 知心托福 直达班(冲100分)

    ¥4080

  • 知心托福 中学生旗舰直达班 (冲110分)

    ¥8280

  • 知心托福 直达班(冲90分)

    ¥3880

分享到:

相关推荐

交流 • 下载

精品课限量免费领

  • 托福听力备考全攻略
  • 托福考试指南_托福新生必修课
  • 新东方雅思托福GRE词汇量在线测试

提分历程更多>>

实用 • 工具

托福课程排行榜本周本月

托福公开课更多>>

新东方在线知心托福介绍说明【热】 w 04分14秒
1 新东方在线知心托福介绍说明【热】
新东方在线唐悦宁:托福词汇遗忘规律 w 07分34秒
2 新东方在线唐悦宁:托福词汇遗忘规律
新东方在线唐悦宁:词根词缀记忆法 w 04分42秒
3 新东方在线唐悦宁:词根词缀记忆法
新东方在线唐悦宁:托福听力基础预备 w 03分30秒
4 新东方在线唐悦宁:托福听力基础预备
新东方在线李镇江:托福听力场景概述-社会科学-美国历史 w 08分35秒
5 新东方在线李镇江:托福听力场景概述-社会科学-美国历史

推荐阅读