Question

    Somewhere in the highlands of Afghanistan, a hungry fox pounces （猛扑）on a tasty-looking leopard gecko （豹纹 壁虎）.But the lizard has a get — out — of — jail — free card: a separable tail. The dropped part waves in an energetic but uncontrolled way around long enough to distract the fox, allowing the gecko itself to run off and hide.

Leopard geckos are one of a few lizard species that possess this ability, known as autotomy （自切）.The technique is effective, but the tail can account for about a quarter of the lizard's body mass. So how do these animals adapt to losing so much of it that quickly?

When geckos lose their tail, they "take this more sprawled posture （四肢伸开的姿势）"and walk with their limbs spread out farther from their body, says Chapman University biologist Kevin Jagnandan. Most researchers initially assumed this posture was a response to a suddenly shifted center of mass. But when Jagnandan observed leopard geckos with a tail in his laboratory, he realized that they wag it as they walk, suggesting that these movements may be key to the lizards' movements.

To test this assumption, Jagnandan and his team assessed the postures of 10 geckos walking in various conditions: with their tail intact （完整的）；with their tail restricted by a small section of glued-on fishing rod （whose mass can be neglected）; and with their tail self-amputated. These comparisons allowed the researchers to distinguish the effects of lost mass from those of lost tail-wagging on the geckos’ movements.

The lizards with an immobilized tail adopted ways similar to those with no tail, the researchers reported in a study published in Scientific Reports. This result suggests the sprawling walk they adopt after losing their tail is not compensating for the missing mass but rather for the lack of tail-wagging. Jagnandan thinks tail movements help the lizards keep balance and stability as they walk. He suspects that the tails of mammals living in trees, such as cats and monkeys, serve a similar purpose.

Bill Ryerson, a biologist at Saint Anselm College, who was not involved in the study, was surprised by the findings. "We thought we had settled it ——it seemed pretty open-and-shut" that mass was the main factor, he says. The new study challenges this earlier idea in a "beautifully simple" way, Ryerson adds.

Jagnandan hopes that understanding how animals react to missing body parts could ultimately help engineers design robots that can move more efficiently as heavy loads — or even entire limbs --- are added and removed.

1.From the first two paragraphs we can learn that ______.

A.the fox likes to play with the gecko's tail

B.the fox falls for the trick of the gecko

C.moving without a tail is much tougher for the gecko

D.the gecko becomes inactive when losing its tail

2.Most researchers once thought geckos adopted the sprawled posture because ______

A.the posture was key to their movements

B.their center of mass had changed

C.the posture was their unique survival skill

D.they imitated other mammals' behavior

3.What can we know about the findings of the study?

A.They are in accordance with the expectation of Bill Ryerson.

B.They were obtained after researchers compared three geckos' movements.

C.They solved several mysteries concerning other mammals.

D.They can be applied to the field of artificial intelligence.

4.What does the passage mainly talk about?

A.Why leopard geckos prefer a habitat in the highlands.

B.How leopard geckos play hide and seek games.

C.How leopard geckos adapt to losing their tails.

D.What role tails play in leopard geckos' life.

Answer

1.B

2.B

3.D

4.C

【解析】

这是一篇说明文。文章主要讲述研究发现蜥蜴在失去尾巴之后，采用四肢伸开的姿势行走是为了弥补摇尾巴这个动作，而不是为了失去的重量。

1.

推理判断题。由第一段的最后一句“The dropped part waves in an energetic but uncontrolled way around long enough to distract the fox, allowing the gecko itself to run off and hide.”可知，这个脱落部分以一种剧烈，但不受控制的方式一直挥动着，这足以使这只狐狸分心，从而使这只壁虎能自己逃脱和躲藏起来。由此可见，这只狐狸受到了这只壁虎的欺骗。结合选项可知，选项B正确。

2.

细节理解题。由第三段的第二句“Most researchers initially assumed this posture was a response to a suddenly shifted center of mass.”可知，大部分的研究者们一开始假设这个姿势是对突然重心转移的一种反应。由此可见，大部分研究者们曾经认为壁虎采用四肢展开姿势是因为它们的重心发生变化了。结合选项可知，选项B正确。

3.

推理判断题。由最后一段“Jagnandan hopes that understanding how animals react to missing body parts could ultimately help engineers design robots that can move more efficiently as heavy loads — or even entire limbs --- are added and removed.”可知，Jagnandan希望了解动物对身体缺失部分是如何做出反应的，这最终能够帮助工程师设计出当超重负荷或者甚至是整个肢体被增加或者移开时，仍然能够更加有效地移动的机器人。 由此可见，这项研究的发现可能会被应用到人工智能领域。结合选项可知，选项D正确。

4.

主旨大意题。由全文内容可知，第二段最后一句“So how do these animals adapt to losing so much of it that quickly?”，第三段的第一句“When geckos lose their tail, they "take this more sprawled posture （四肢伸开的姿势）"and walk with their limbs spread out farther from their body, says Chapman University biologist Kevin Jagnandan.”，以及第五段第二句“This result suggests the sprawling walk they adopt after losing their tail is not compensating for the missing mass but rather for the lack of tail-wagging.”可知，这些动物是如何迅速地适应失去如此多的尾巴？查普曼大学生物学家Kevin Jagnandan说，当壁虎失去它们的尾巴时，它们会采用这种四肢伸开的姿势，然后用从身体伸展开来的四肢来行走。这个结论表明它们在失去它们的尾巴之后采用的四肢伸开行走不是对缺失重量的弥补，而是对摇尾巴动作缺失的弥补。由此可见，本文都是在讲述壁虎是如何去适应失去尾巴的。结合选项可知，选项C正确。