Question

    “Jewel wings fly around like little helicopters until they see preys (猎物), usually smaller flying insects,” said Bellido, a biologist at the University of Minnesota. “Then they dash at their meals in a burst of speed.”

You might mistake jewel wings for their cousins, dragonflies. New research shows that these two insects share something more significant than their appearance, however. In a paper published in Current Biology, Dr. Bellido and the dragonfly colleagues reveal that the neural (神经的) systems behind jewel wings’ vision are shared with dragonflies, with whom they have a common ancestor that lived before dinosaurs. But over the centuries, this brain wiring has adapted itself in different ways in each creature, enabling sharply different hunting strategies.

Jewel wings’ behavior involves attacking what’s directly in front of them, the team found. But recordings made in the lab by Dr. Gonzalez and her colleagues confirmed that dragonflies rise up in a straight line to seize unsuspecting insects from below. Researchers are particularly interested in the neurons (神经元) that send visual information to the wings.

To look closer at the neurons linking vision and flight, the researchers equipped jewel wings with sensors and showed them a video of a moving dot, comparing it with earlier dragonfly research. When a neuron fired, a popping sound filled the researchers’ ears, allowing them to tell exactly which movements-left, right, up, down or some combination-each neuron responded to. Jewel wings best see what’s right in front of them, they found, while dragonflies’ clearest vision is just above them.

The team was interested to find that while jewel wings’ neurons didn’t always respond like those in dragonflies, the number of neurons and organization were similar. That suggests that the system that conveys this information from the eyes to the wing muscles did not evolve recently, but has roots that are millions of years older than the oldest dinosaurs. And that ancient common ancestor likely had already developed remarkable speed in both vision and flight. Then, in the following years, the system has evolved to suit individual insect species.

This shared neural system may be more than 250 million years old, but it is also flexible enough to transform itself to meet the needs of a variety of creatures in different eras and environments, the findings suggest.

1.Jewel wings usually catch their meals ________ them.

A.on the right of B.on the left of

C.straight ahead of D.at the back of

2.What is Paragraph 4 mainly about?

A.What actions jewel wings take to catch preys.

B.How jewel wings ‘neurons respond to vision.

C.When jewel wings start to hunt for their preys.

D.Where researchers did the research into jewel wings.

3.What can we learn about dragonflies and jewel wings from the passage?

A.The two insects possess similar neural systems.

B.Jewel wings’ vision is sharper than dragonflies’.

C.Dragonflies ‘brain wiring is the same with jewel wings’.

D.The oldest dinosaurs react as rapidly as the two insects.

4.What is the main purpose of the passage?

A.To analyse the habits of two similar insects.

B.To tell the difference between dragonflies and jewel wings.

C.To assess the effects of different insects ‘hunting strategies.

D.To present the result of a study on two insects neural systems.

Answer

1.C

2.B

3.A

4.D

【解析】

这是一篇说明文。文章主要介绍一项新研究发现比起外貌，豆娘和蜻蜓一起分享更重要的视觉神经系统，但是这两种昆虫的视觉神经系统对具体的视觉反应又有所不同。而且该团队还发现这两种昆虫神经的数量和结构也是相似的。

1.细节理解题。由第三段的第一句“Jewel wings’ behavior involves attacking what’s directly in front of them, the team found.”和第四段的最后的一句“Jewel wings best see what’s right in front of them, they found, while dragonflies’ clearest vision is just above them.”可知，该团队发现豆娘的行为包括了袭击刚好在它们前面的物体，豆娘最好的视觉就是这个物体刚刚好在它们前面，然后蜻蜓最清晰的视觉恰好是在它们上面。由此可见，豆娘通常可以抓住刚好在它们前面的食物。结合选项可知，C选项正确。

2.主旨大意题。由第四段的第一句“To look closer at the neurons linking vision and flight, the researchers equipped jewel wings with sensors and showed them a video of a moving dot, comparing it with earlier dragonfly research.When a neuron fired, a popping sound filled the researchers’ ears, allowing them to tell exactly which movements-left, right, up, down or some combination-each neuron responded to. Jewel wings best see what’s right in front of them, they found, while dragonflies’ clearest vision is just above them.”可知，为了更近距离地观察连接视觉和飞行的神经元，研究人员在豆娘上安装了传感器，并向它们播放了一个移动点的视频，将其与早期的蜻蜓研究进行了比较。当一个神经元被激发时，研究人员的耳朵里充满了爆裂的声音，让他们准确地分辨出每个神经元对哪个动作有反应——左、右、上、下或者某种组合。 他们发现，豆娘最能看清眼前的东西，而蜻蜓最清晰的视野就在它们的上方。由此可知，本段主要是在介绍豆娘的神经元对视觉是如何反应的。故B选项正确。

3.细节理解题。由第五段第一句“The team was interested to find that while jewel wings’ neurons didn’t always respond like those in dragonflies, the number of neurons and organization were similar.”可知，该团队有趣地发现虽然豆娘的神经元不总是像蜻蜓的神经元那样反应，但是它们的神经元数量和结构是相似的。由此可见，豆娘和蜻蜓拥有相似的神经元系统。结合选项可知，A选项正确。

4.推理判断题。由整篇文章内容可知，第二段的第三句“In a paper published in Current Biology, Dr. Bellido and the dragonfly colleagues reveal that the neural (神经的) systems behind jewel wings’ vision are shared with dragonflies, with whom they have a common ancestor that lived before dinosaurs.” 表示的是在《当代生物学》杂志上发表的一篇论文中，伯利多博士和他的蜻蜓同事们揭示了豆娘视觉背后的神经系统与蜻蜓是共享的，它们有一个共同的祖先，生活在恐龙之前。第三段最后一句“Researchers are particularly interested in the neurons (神经元) that send visual information to the wings.”表示的是研究者们特别对发送视觉信息给豆娘的神经元感兴趣。第四段的第一句“To look closer at the neurons linking vision and flight, the researchers equipped jewel wings with sensors and showed them a video of a moving dot, comparing it with earlier dragonfly research.”表示的是为了更靠近地观察这些神经元将视觉和飞行连接起来的功能，研究者们和早期的蜻蜓研究对比，给豆娘装上了传感器，并且向它们展示了一段移动点的视频。以及第五段的“The team was interested to find that while jewel wings’ neurons didn’t always respond like those in dragonflies, the number of neurons and organization were similar.” 表示的是该团队有趣地发现虽然豆娘的神经元不总是像蜻蜓的神经元那样反应，但是它们的神经元数量和结构是相似的。由此可见，本文首先介绍豆娘的视觉神经系统和蜻蜓的是共享的，紧接着研究人员深入地去观察神经元和视觉之间具体的联系，最后又发现了它们神经元数量和结构的相似性。由此判断出这篇文章的主要目的是介绍两种昆虫神经系统的研究结果。故D选项正确。