题干

在某森林的固定位置和固定时间,用固定数量的鸟笼捕捉的方法,统计大山雀种群数量.在连续10年内得到如图所示的曲线(图中λ表示该种群数量是前一年种群数量的倍数),下列分析不正确的是(  )

A:在10年内大山雀的种群数量第4年种群数量最大

B:2~6年内种群的年龄组成为衰退型

C:种群数量下降是从第4年后开始

D:第8年种群数量达到最低,此后保持相对稳定

上一题 下一题 0.0难度 选择题 更新时间:2019-06-06 07:08:34

答案(点此获取答案解析)

B

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阅读理解

    A guiding principle for master cellist Yo-Yo Ma is that “the intersection(交汇) of cultures is where new things appear.” Certainly his biography is an intersection of cultures. He was born to Chinese parents in Paris, France; both his parents were musicians. When he was seven, his family moved to the United States. Gifted for his age, Ma attended Juilliard, the world famous music institute. He then chose to earn a liberal arts degree at Harvard rather than focusing only on music.

    Even in his earliest performing years, Yo-Yo Ma had a strong belief that it was important to share music with all kinds of people. Stories are told about how he once performed in the hallway of a large building for people who were unable to get tickets to his concert. He remained interested in making music accessible to diverse audiences and furthered his interest in different cultures when he visited the Bushmen of the Kalahari. He developed a vehicle to further these ideals when he founded the Silk Road Project.

    As he has said, the Silk Road is a metaphor(隐喻) for a number of things: as the Internet of ancient times, the routes were used for trade, by religious people, adventurers, scientists, storytellers. Everything from algebra to Islam moved along the Silk Road. It's the local-global thing. In the cultural world, you want to make sure that voices don't get lost, that rich traditions continue to live, without becoming common.

    This lesson explores the philosophy behind Yo-Yo Ma's founding of the Silk Road Ensemble(乐团), his belief that the arts, and particularly music, can make the world better, and that through cooperation, one can both preserve tradition and shape cultural evolution. Students also explore their own attitudes toward the arts, writing reflective essays on how the arts have played a role in their own lives.