Question 18 is based on the recording you have just heard.

Recording One

听力原文

       Good afternoon, class! Today I want to discuss with you a new approach to empirical research. In the past, scientists often worked alone. They were confined to the university or research center where they worked. Today, though, we are seeing mergers of some of the greatest scientific minds, regardless of their location. There has never been a better time for collaborations with foreign scientists. In fact, the European Union is taking the lead. (16) Spurred on by funding policies, half of European research articles had international co-authors in 2007. This is more than twice the level of two decades ago.

       The European Union’s level of international co-authorship is about twice that of the United States, Japan and India. Even so, the levels in these countries are also rising. This is a sign of the continued allure of creating scientific coalitions across borders. András Schubert, a researcher at the Institute for Science Policy Research, says that the rising collaboration is partly out of necessity. This necessity comes with the rise of ‘big science’. (17) Many scientific endeavors have become more complicated. These new complications require the money and labor of many nations. 

       But he says collaborations have also emerged because of increased possibilities: the Internet allows like-minded scientists to find each other. Simultaneously, dramatic drops in communication costs ease long-distance interactions. And there’s a reward: studies of citation counts show that internationally co-authored papers have better visibility. Schubert says international collaboration is a way to spread ideas in wider and wider circles.

       Caroline Wagner, a research scientist at George Washington University, notes that international collaborations offer additional flexibility. Whereas local collaborations sometimes persist past the point of usefulness because of social or academic obligations, international ones can be cultivated and dropped more freely.

       The collaborative trend is true across scientific disciplines. Some fields, though, have a greater tendency for it. Particle physicists and astronomers collaborate often. This is because they must share expensive facilities. (18) Mathematicians, by contrast, tend historically towards solitude. As a consequence, they lag behind other disciplines. However, Wagner says partnerships are rising there too. The level of collaboration also varies from country to country. “There are historical and political reasons as to why collaborations emerge,” says Wagner. This rise is also apparently boosted by policies embedded in European framework funding schemes. These policies underlie funding requirements that often require teamwork.

18. What do we learn about the field of mathematics?

解析：B。录音指出，相比之下，从历史上看，数学家倾向于独自研究。因此，他们落后于其他学科。B选项中lags behind other disciplines为原词复现，故为正确答案。C项为过度推断，故排除。D项中的independently虽与录音中的solitude为近义词，但录音中并未提及独立研究是对数学家的要求，而是一种趋势，故D项错误。