Question

A biologist from the National Park Service discovered a rare and unusual mammoth(猛犸) skull(颅骨) buried in a 13,000-year-old rock layer on the Santa Rosa Island, the second largest landmass in the Channel Islands, California. The fossil of the extinct giant animal is leaving many paleontologists(古生物学家) scratching their heads. Despite the fact that it’s possibly the best preserved mammoth skull ever found and of high scientific importance, the species of the individual it belonged to can’t seem to be identified yet—it’s too big to be a pygmy(特别矮小的) mammoth and too small to have come from a Columbian mammoth. Some say it’s a new species while others believe the truth lies somewhere in between.

The first mammoths showed up in North America around two million years ago, but it was only during the last two ice ages that the Columbian species, which could grow to be up to 14 feet tall, made its way to the Channel Islands 100 miles west of Los Angeles. Once the ice melted, many populations became trapped on the island and evolved into pygmy mammoths, an endemic species(地方种) to the Channel Islands which grew only to six feet tall.

Judging from its size, the newly found mammoth skull doesn’t seem to fit any of the two species, Columbian or pygmy. To make things even more confusing, one of its two tusks(象牙) is nearly five feet long and coiled in a manner that resembles those of fully grown mammoths but the left tusk is shorter and sloped, more like a juvenile(青少年).

This has caused some scientists to say the Santa Rose skull may belong to a transitional species. Whatever’s the case, a following examination of the mammoth’s teeth should put the matter to rest. The analysis will also tell us how old the mammoth was when it died, so we can tell for sure whether it was an adult or juvenile.

More interesting than the mammoth’s lineage, however, might be its story. The giant mammal lived 13,000 years ago or roughly the same timeline of the “Arlington Man”, a 13,000-year-old human skeleton also found on Santa Rosa. Some 3,000 years later humans were already spread throughout the continent and the Channel Islands’ mammoth went extinct. The present finding might help reveal a link between the two.

The remains also seem to confirm a long-held assumption that there were two mammoth migrations to the Channel Islands. “The discovery of this mammoth skull increases the probability that there were at least two migrations of Columbian mammoths to the island: during the most recent ice age 10,000 to 30,000 years ago, as well as the previous ice age that occurred about 150,000 years ago,” said USGS geologist Dan Muhs.

1.The underlined part in the first paragraph means the paleontologists feel ________.

A. excitedB. confusedC. anxiousD. frustrated

2.Which of the following is not among the reasons why the newly found skull is special?

A. It is possibly the best preserved mammoth skulls.

B. Its size fits neither the Columbian mammoth nor the pygmy mammoth.

C. It was found on the Santa Rose Island, California.

D. Its two tusks give out different information of the mammoth’s age.

3.What can be inferred from the last three paragraphs?

A. The examination of the mammoth’s teeth can tell us how old it was when it died.

B. There may be a link between the extinction of mammoths and the spread of humans.

C. At least two mammoth groups migrated to the Channel Islands during different periods of time.

D. There remains no final conclusion as to how many mammoth groups migrated to the Islands.

4.This passage mainly tells us the newly found mammoth skull _________.

A. is among the best preserved, but with a mysterious story

B. has aroused a debate over what species it belongs to

C. is of great scientific importance to mankind

D. is likely to confirm a former assumption

Answer

1.B

2.C

3.D

4.A

【解析】

试题分析：文章主要介绍了在加州发现的猛犸颅骨化石给科学家带来的疑团和困惑。

1.B 词义猜测题。依据第一段内容可知，新发现的异常的猛犸化石让生物学家都感到困惑，B项是“困惑的”，故选B。A项是“激动的”；C项是“着急的”；D项表示“沮丧的”。

2.C 细节理解题。该题可以用排除法进行，依据题干的要求即“这个头盖骨特别的的地方在哪？”，C项只是告知一个事实，不存在如何特别之处，故C项适合。

3.3】D 推理判断题。依据文章最后一段的内容可知，A项和B项内容是文章段落里直接有的，可以排除；C项根据最后的“The discovery …about 150,000 years ago”也是直接给出的，也不适合。D项中的“how many mammoth groups”这个细节文章没有，只能是推断出。

4.4】A 主旨大意题。依据文章的内容概述可知，新发现的异常的猛犸头骨给生物学家带来了诸多困惑，有很大的科学研究价值，但目前还不知道它到底属于哪个物种，且A项的概括比B项更为全面，故A项正确。

【名师点拨】

推理判断题。要求在理解原文表面文字信息的基础上，做出一定的推理判断，从而得到文章的隐含意义和深层意义。推理判断题所涉及的内容可能是文中的某一句话，也可能是某几句话，所以，推理题的答案只能是根据原文表面文字信息一步推出的答案：即对原文某一句话或某几句话所作的同义改写或综合。推理判断题的题干中通常含infer, suggest, imply, conclude，indicate等标志性词语。 这种题型主要包括细节判断题、态度观点推断题、写作意图推断题、文章出处判断题和猜测想象推断题。5.3】D 推理判断题 依据文章最后一段的内容可知A项和B项内容是文章段落里直接有的，可以排除；C项根据最后的“The discovery …about 150,000 years ago”也是直接给出的，也不适合。 D项中的“how many mammoth groups”这个细节文章没有只能是推断出。

考点：考查科普类文章阅读