题目内容：

    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.