题文
Scientists have long puzzled over how iguanas, a group of lizards(蜥蜴) mostly found in the Americas, came to live in the isolated Pacific islands of Fiji and Tonga. Some scientists used to suppose that they must have traveled there on a raft, a journey of around 5,000 miles from South America to the islands. There are documented cases of iguanas reaching remote Caribbean islands and the Galapagos Islands on floating logs. But new research in January by Brice Noonan and Jack Sites suggested that iguanas may have simply walked to Fiji and Tonga when the islands were still a part of an ancient southern supercontinent.The ancient supercontinent was made up of present-day Africa, Australia, Antarctica and parts of Asia. If that’s the case, the island species would need to be very old. Using “molecular (分子) clock” analysis of living iguanas’ DNA, Noonan and Sites found that, sure enough, the lineage of iguanas has been around for more than 60 million years—easily old enough to have been in the area when the islands were still connected by land bridges to Asia or Australia.
Fossils (化石) uncovered in Mongolia suggest that iguanid ancestors did once live in Asia. Though there’s currently no fossil evidence of iguanas in Australia, that doesn’t necessarily mean they were never there. “The fossil record of this continent is surprisingly poor and cannot be taken as evidence of true absence,” the authors write.
So if the iguanas simply walked to Fiji and Tonga from Asia or possibly Australia, why are they not also found on the rest of the Pacific islands? Noonan and Sites say fossil evidence suggests that iguana species did once inhabit other islands, but went extinct right around the time when humans settled in those islands. But Fiji and Tonga have a much shorter history of human presence, which may have helped the iguanas living there to escape extinction.
The researchers say that their study can’t completely rule out the rafting theory, but it does make the land bridge theory “far more reasonable than previously thought.”
小题1: What did some scientists previously believe about the iguanas?A．They were once discovered in America.B．They traveled by raft to Fiji and Tonga.C．They could survive in poor living conditions.D．They moved to Fiji and Tonga from Australia.小题2:According to Noonan and Sites, 60 million years ago ____. A．the land of the world was a supercontinentB．Fiji and Tonga were connected to Asia or Australia C．Africa, Australia and America were a continentD．iguanas walked to Fiji and Tonga from Africa小题3:The underline word “lineage” in Paragraph 2 probably refers to ____.A．conditions in which creatures can surviveB．the change in ancient plants and animals.C．the line of generations of an ancestorD．the habitat of a type of an ancient animal小题4: What is the main topic of this passage? A．The life span of animals living on the ancient supercontinent.B．The two islands being home to several iguana species in the Pacific region.C．The fossil evidence suggesting iguanas’ ancestors’ swimming to Fiji and Tonga D．By raft or by land — how did iguanas reach the tiny Pacific islands? 题型：未知难度：其他题型
答案
小题1:B
小题2:B
小题3:C
小题4:D
解析
本文主要讲述了lizards在世界上很多地方都可以找到。尤其是在一些与世隔绝的太平洋里的岛屿之上。文章中对于这个现象进行了研究，分析了多种可能性。小题1:B
【试题解析】细节题。根据第一段2,3,4行Some scientists used to suppose that they must have traveled there on a raft, a journey of around 5,000 miles from South America to the islands.可知以前科学家认为蜥蜴是通过筏子等工具到达斐济和汤加的。故B正确。
小题2:B
【试题解析】推理题。根据第二段最后2行more than 60 million years—easily old enough to have been in the area when the islands were still connected by land bridges to Asia or Australia.可知他们认为在6千万年前，蜥蜴居住的地方通过大陆桥和亚洲，澳大利亚是连接在一起的。故B正确。
小题3:C
【试题解析】推理题。根据本句Noonan and Sites found that, sure enough, the lineage of iguanas has been around for more than 60 million years—easily old enough to have been in the area when the islands were still connected by land bridges to Asia or Australia.可知他们认为蜥蜴从6千万年前一直存在了，就生存在通过大陆桥和亚洲或者澳大利亚相连接的地方。所以the lineage 指C项某一个动物的祖先的血统。故C正确。
小题4:D
【试题解析】主旨大意题。本文主要讲述了lizards在世界上很多地方都可以找到。尤其是在一些与世隔绝的太平洋里的岛屿之上。文章中对于这个现象进行了研究，分析了多种可能性。故D正确。
【长难句解析】
Scientists have long puzzled over how iguanas, a group of lizards(蜥蜴) mostly found in the Americas, came to live in the isolated Pacific islands of Fiji and Tonga.
【翻译】很久以来科学家一直都很困惑一种通常在美洲被发现的蜥蜴如何来到与世隔绝的太平洋上的斐济和汤加岛上生活。
【分析】本句中介词over的后面含有一个宾语从句how iguanas, a group of lizards(蜥蜴) mostly found in the Americas, came to live in the isolated Pacific islands of Fiji and Tonga.这个宾语从句里有一个过去分词短语mostly found in the Americas用来修饰前面的名词iguanas, a group of lizards。
考点
据考高分专家说，试题“Scientists have long.....”主要考查你对 [日常生活类阅读 ]考点的理解。日常生活类阅读
日常生活类阅读的概念：
日常生活这一话题主要涉及人们衣食住行等方面的活动。这一话题的选材主要针对人们日常的工作，生活以及学习情况。做这一类题时，最主要的是要把握好人物的活动内容，时间和地点。
日常生活类阅读题答题技巧：
【题型说明】
该类文章内容涉及到人们的言谈举止、生活习惯、饮食起居、服饰仪表、恋爱婚姻、消遣娱乐、节日起源、家庭生活等。文章篇幅短小，追根溯源，探索各项风俗的历史渊源，内容有趣。命题也以送分题为主，如事实细节题、语义转换题、词义猜测题和简单推理判断题等。虽然这类文章读起来感觉轻松，试题做起来比较顺手，但绝不能掉以轻心。因为稍不留神，就会丢分。
【备考提醒】
为了保证较高准确率，建议同学们做好以下几点：
1、保持正常的考试心态。笔者在教学中发现，越是容易的试题，同学们越是容易失分。为什么呢？因为在这种情况下，同学们极易产生麻痹思想，认为题目好做，就不引起高度重视，于是思维不发散、不周密。而命题人就是利用同学们的这一弱点，设计陷阱题。所以，无论试题难易与否，我们都要保持正常的考试心态。试题容易，不欣喜；试题难，不悲观。
2、根据前面讲到的方法，认认真真、细细心心做好事实细节题。
3、做好语义转换题。这类题是根据英语中一词多义和某些词语在文中能表达一定的修辞意义的原则而设计的。要求同学们解释某生词的含义，确定多义词或短语在文中的意思，确认文中的某个代词所指代的对象，或者对英语中特有的表达、格言、谚语进行解释。这种题要求同学们一定要根据上下文猜测词义或理解句子，切不可望文生义。
4、做好简单推理判断题。简单推理判断题要以表面文字为前提，以具体事实为依据进行推理，做出判断。这种推理方式比较直接，只要弄清事实，即可结合常识推断出合理的结论。
