15.
The unique coloration (自然花纹) of the giant panda that is loved by many people has long been a mystery to scientists.But now a joint research team believes they have solved the mystery,once and for all.
The black and white patches on the giant panda mainly have two functions-camouflage (伪装) and communication,the joint research team from University of California,Davis,and California State University,Long Beach explains.
The giant panda's white face,the back of ear,the back of tongue,belly,and rump(臀部)are adapted for crypsis (隐蔽) against a snowy background,whereas its black shoulders and legs are adapted for crypsis in shade,according to the study that the joint research team published in the journal of Behavioral Ecology on Feb.28.
However,dark markings on the head are not used in crypsis,but in communication:dark ears may be involved with signaling intention about aggressive behavior while dark eye marks may serve in individual recognition,according to the study.
There is no strong evidence for their fur color being involved in temperature regulation,disrupting the animal's outline or in reducing eye glare,the study explains.
"Understanding why the giant panda has such striking coloration has been a long-standing (存在已久的) problem in biology that has been difficult to tackle because actually no other mammal has this appearance,making analogies difficult,"said Dr.Tim Karo,a professor from the University of California and the lead researcher.
28.Which of the following body parts of pandas serve as intention of violence?A
A.Dark ears.B.White face.C.White belly.D.The dark markings on the head.
29.The underlined word"tackle"in the last paragraph is closest in meaning toB.
A.analyze B.solve C.discover D.face
30.Which of the following statements is FALSE?C
A.The white legs are used for disguise in shade.
B.The dark eye marks may act as individual recognition.
C.The fur color of a panda is involved in temperature regulation.
D.The white rump of the panda is used for disguise against a snowy background.
31.Where would you be most likely to find the text?D
A.a science fiction B.Children's literature C.an official document D.a science report.