15 Hypothesis on Biological Clocks of Migrants
動物學：介紹候鳥飛行機制的三種假說

導讀

候鳥遷徙為什么不會迷失方向呢？科學家們經過反復多次的觀察與研究發現，原來世界上的候鳥，不管是白天飛行的，還是夜間飛行的，它們都有一種特殊的導航本領。

 

A mysterious phenomenon is the ability of over-water migrants to travel on course. Birds, bees, and other species can keep track of time without any sensory cues from the outside world, and such “biological clocks”clearly contribute to their “compass sense.”For example, they can use the position of the Sun or stars, along with the time of day, to find north. But compass sense alone cannot explain how birds navigate the ocean: after a flock traveling east is blown far south by a storm, it will assume the proper northeasterly course to compensate. Perhaps, some scientists thought, migrants determine their geographic position on Earth by celestial navigation, almost as human navigators use stars and planets, but this would demand of the animals a fantastic map sense. Researchers now know that some species have a magnetic sense, which might allow migrants to determine their geographic location by detecting variations in the strength of the Earth's magnetic field.

Sentence Translation

翻譯練習

1. Birds, bees, and other species can keep track of time without any sensory cues from the outside world, and such “biological clocks” clearly contribute to their “compass sense.”

2. Perhaps, some scientists thought, migrants determine their geographic position on Earth by celestial navigation, almost as human navigators use stars and planets, but this would demand of the animals a fantastic map sense.

Key

1．鳥類、蜜蜂及其他生物物種能夠在沒有任何外界感覺提示的情況下掌握時間。這種“生物鐘”本能顯然有助于其“指南針定向的感覺”。

2．也許有些科學家認為，候鳥使用天文導航法確定其在地球上的地理位置，跟人類航海者利用恒星和行星導航幾乎一模一樣。但這就要求這些動物具有一種異想天開的地圖感覺。

Emulation

美文自己寫得出——學生仿寫

仿寫范例

Should University Students Go in for Business?

People keep asking a question: where does the knowledge essential for a successful existence come from, books or experience? Some people who are against the idea of students doing business during university education say that students should use their time to focus exclusively on studying, while others believe that it is good for university students to adapt to society in this way. I side with the latter, in the belief that doing business helps students know more about their majors, provides valuable practical experience and allows them a feeling of success and independence that is a perfect complement to their academic pursuit.

A popular criticism of universities is that they are “ivory towers” or places where study and research are divorced from the “real world.” Doing business related to their majors could give students an exciting chance to apply the theories they have learned in class. For example, financial theory is a notoriously abstract and difficult subject. When a student takes chances to operate his own business, no matter how small it might be, he might discover that the abstract words in classes may somehow turn out to be useful business strategies in reality. And this student might return to his financial theory class happily with renewed vigor and a filled wallet. It is in doing business that an abstract academic pursuit becomes a concrete and interesting goal with a real relationship to the student's life.

Doing business during university education also helps students strengthen their resumés, build important contacts with different companies and equip them with necessary communicating skills. All of these are very important practical experience that they could not get from textbooks. For no matter how hard they try, textbook publishers could barely keep up timely with the rapid development of society, or the complex interpersonal relationship in the real world. Besides, when the students graduate from universities, they could make full use of the social relations built during the experience to find a proper job, or to approach other employers with good references and cutting-edge work experience.

Finally, the feeling of success that comes from holding a business can build students' confidence. Knowing that they can run a business well and be paid for their endeavors is an important character-building experience that many students put off for too long. Learning to manage the money that they make will be another reward that would be a critical part for their future lives. Even if they might make mistakes in handling their money during this period, the results will probably not be disastrous, but will teach them valuable lessons that they will be sure to remember in the future when they will be truly independent.

In a word, the advantages of university students going in for business during university education obviously outweigh the disadvantages. Although they might be faced with some setbacks in operating their business, the students could, through fair and foul, gain more in going through the challenges. They could relate what is leant in books to the real situations, make their resumés impressive, and above all, build up confidence. As long as they could tackle well the relationship between study and business, the reward would go beyond monetary gain.