相关试卷

Male chingolos learn their unique, two-second melody from adult males. "It is a distinctive song — like a fingerprint, but learned," says one of the researchers. "It serves to attract females and protect territory. It is the bird's way of saying, "This is me, and here I am." However, urbanization and habitat loss have broken this learning chain, causing local song "dialects" to disappear.

Driven by this problem, researchers took on a pioneering task: bringing back a song that had disappeared from the wild — known only from a musical record made in the 1960s — to a population of chingolos.

Using physics-based modeling of the bird's vocal tract (声道) , the team first created an accurate artificial version of the lost song. They then engineered this model into a physical device designed to broadcast the forgotten melody — a "robotic tutor." This artificial song was introduced to the chingolos in the park during their critical learning period from October to February. The sessions took place during peak singing hours and were limited to a maximum of eight hours. There were random pauses (停顿) in between so that the birds interpreted the playback from the three devices placed in the area as a real exchange, as if these devices were responding to each other. This stimulated the birds' vocal responses.

The results were impressive. Young chingolos learned and adopted the song, though they added their own population's "accent" to the final trill (颤音) , which showed that their singing is shaped by learned behaviors and inborn characteristics.

"This is about preserving not just genetic, but cultural biodiversity," says another researcher. The team is now developing AI systems to automatically identify individual bird songs and planning to study cultural spread in bird populations to ensure that bird culture is not lost again.

Two friends joined me on a four-day wilderness getaway, and since we were all in our seventies, we decided we'd better go while we still could. Our adventure began with a scary drive up a winding mountain road.

On one hike, I found myself hanging onto a wire on a bridge made of two partly rotten (腐烂的) logs, suspended high above rushing rapids. I would never have attempted it without our guide ahead, mouthing encouraging words. Fixing my eyes on her boots, I inched along the shaky logs. Somehow, I made it across, flooded with a rush of intense excitement and huge relief.

Later, after spotting bear tracks, we were told to make loud noises, which soon became a game once the tension faded.

Until suddenly, time stood still.

We had just crossed a stream when the guide whispered, "There's a bear." I looked up in disbelief and saw not one, but two, about ten meters above us— the brown mother in front, her cub behind.

Though scared speechless, I couldn't help noticing how beautiful they looked in their natural setting. I wondered if it would be my last memory. As they started towards us, we recovered enough to shout and wave our hiking poles. Taken aback, they stopped, and then slowly turned away. Another fear was overcome!

On our final morning, after a quiet, thoughtful walk through the forest, we were asked to bring back a "meaningful" stick, rock, and leaf to share what would "stick" with us, what "rocked," and what we would "leaf" behind. The bond of friendship would stick with me. Women supporting one another truly rocked. And I hoped to leave some fears behind.

Our guide ended by expressing her admiration, praising not only our fitness but also our positive attitude, and saying she hoped to be like us in another thirty or forty years. Those unexpected words warmed my heart and eased my fear of being "over the hill." Being valued for what we had accomplished felt like winning an Olympic medal — even if just for participation.

Contest Rules

● Each individual contestant or team must choose a working language for their problems and solutions, a choice that cannot be changed less than two weeks before the Olympiad begins.

● The individual contest involves solving five problems in six hours, whereas the team contest features one problem with two hours less.

● Unless instructed, giving multiple answers will receive zero marks. Besides, a detailed explanation is required for each answer; failure to provide one will result in a lower score.

Awards

The team contest will award up to one gold, two silver, and three bronze medals. In the individual contest, the number of gold, silver, and bronze medals awarded shall be in the ratio 1: 2: 3, with the total number of medals being between one quarter and one third of the contestants. Click here to find out other awards.

注意：1．写作词数应为80左右；2．请按如下格式在答题卡的相应位置作答。

My Favourite Song

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我们都很感激能有机会向这样伟大的老师学习。

显然，你在这次考试中付出了很大的努力。

这项研究的目的是更好地理解这种疾病。

极少艺术家对音乐有和他同样的影响。

已经证实孩童时期吃蔬菜有助于你往后抵抗严重疾病。

那些充分利用大学的机会和资源的学生受益最多。

读历史是很好的体验，因为它能使我们思考生活在很久以前的人们的社会和经济生活。

在她为舞会装扮之前她突然发现她没有项链。

她几乎不可能在这么短的时间内完成这个工作量。

如果你留心观察的话，你会更容易发现身边的美。