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:军舰鸟可连续飞行两个月-托福听力下载

2016-11-21 16:16:16 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:军舰鸟可连续飞行两个月

  科学美国人60秒中英文翻译:军舰鸟可连续飞行两个月

  科学美国人60秒英文文本

  This is Scientific American — 60-Second Science. I'm Julia Rosen.

  Got a minute?

  Great frigate birds are extraordinary creatures. They're seabirds with six-foot wingspans, yet they weigh only about three pounds. Their preferred food: flying fish—which they pluck out of the air above the water's surface. Frigate birds' feathers aren't waterproof, so landing on the water to fish is a no-go.

  Now, scientists have discovered that great frigate birds do something else amazing: they can fly for up to two months at a time without landing.

  Researchers already knew that these birds took extended trips over the Indian and Pacific Oceans to feed. But in a new study, scientists used tracking devices to follow the movement and vital signs of birds from the island of Europa, near Madagascar. They discovered that the birds have a highly specialized strategy for staying aloft.

  "When they are traveling, most of the time, they flap very infrequently their wings."

  Henri Weimerskirch, an ecologist at the National Center for Scientific Research in France.

  "In fact, what they are doing, they are doing sort of a roller coaster flight where they take altitude. Even they can climb up to 3,000 or 4,000 meters, and when they climb, they do not flap their wings at all."

  Weimerskirch and his colleagues found that the birds climb currents of rising air associated with cumulus clouds, circling upwards the way hawks and vultures do over land. Then they glide back down again, hardly flapping. By using atmospheric conditions to their advantage, the birds covered an average of 420 kilometers a day almost effortlessly. The study is in the journal Science.

  The researchers also discovered that the birds endure some harrowing conditions on their voyage, including some thrills and chills.

  "When you enter into the clouds, there's a lot of turbulence. After, when you see from the recording on the logger of the bird, when they are at 4,000 meters, the temperatures are negative. It's a tropical bird. It's a bird that has no specific down like geese that are operating in the Arctic. So they are encountering sort of a polar temperature, but it's a typical tropical bird."

  Of course, the birds have to eat during their journey. The researchers found that diving down to the sea surface to snatch a meal consumed most of the birds' energy, even though it only occupied about 10 percent of their time.

  "When they are climbing, they have a period where there is no movement at all during several minutes. And so, during this time is probably the time when they are sleeping."

  That's right—like many others who make long-distance flights, great frigate birds catch a little shut-eye along the way.

  Thanks for listening for Scientific American — 60-Second Science Science. I'm Julia Rosen.

  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