还没有登录哦！
[Reading Comprehension]
试题详情
文章：
| Line | Conodonts, the spiky phosphatic remains (bones |
| and teeth composed of calcium phosphate) of | |
| tiny marine animals that probably appeared about | |
| 520 million years ago, were once among the most | |
| (5) | controversial of fossils. Both the nature of the |
| organism to which the remains belonged and the | |
| function of the remains were unknown. However, | |
| since the 1981 discovery of fossils preserving not | |
| just the phosphatic elements but also other remains | |
| (10) | of the tiny soft-bodied animals (also called conodonts) |
| that bore them, scientists' reconstructions of the | |
| animals' anatomy have had important implications | |
| for hypotheses concerning the development of the | |
| vertebrate skeleton. | |
| (15) | The vertebrate skeleton had traditionally been |
| regarded as a defensive development, champions of | |
| this view postulating that it was only with the much | |
| later evolution of jaws that vertebrates became | |
| predators. The first vertebrates, which were soft- | |
| (20) | bodied, would have been easy prey for numerous |
| invertebrate carnivores, especially if these early | |
| vertebrates were sedentary suspension feeders. | |
| Thus, traditionalists argued, these animals developed | |
| coverings of bony scales or plates, and teeth were | |
| (25) | secondary features, adapted from the protective |
| bony scales. Indeed, external skeletons of this | |
| type are common among the well-known fossils of | |
| ostracoderms, jawless vertebrates that existed from | |
| approximately 500 to 400 million years ago. | |
| (30) | However, other paleontologists argued that many of |
| the definitive characteristics of vertebrates, such as | |
| paired eyes and muscular and skeletal adaptations | |
| for active life, would not have evolved unless the | |
| (35) | first vertebrates were predatory. Teeth were more |
| primitive than external armor according to this view, | |
| and the earliest vertebrates were predators. | |
| The stiffening notochord along the back of the | |
| body, V-shaped muscle blocks along the sides, | |
| (40) | and posterior tail fins help to identify conodonts as |
| among the most primitive of vertebrates. The lack of | |
| any mineralized structures apart from the elements | |
| in the mouth indicates that conodonts were more | |
| primitive than the armored jawless fishes such as the | |
| (45) | ostracoderms. It now appears that the hard parts that |
| first evolved in the mouth of an animal improved its | |
| efficiency as a predator, and that aggression rather | |
| than protection was the driving force behind the origin | |
| of the vertebrate skeleton. |
题目：
According to the passage, the anatomical evidence provided by the preserved soft bodies of conodonts led scientists to conclude that
选项:
答案:
D
提问：
老师 这个文章我感觉我通篇都没读明白了 能不能说说这道题如何定位和解题的思维QAQ
解答：
点赞2
阅读999
提问：
老师 这个文章我感觉我通篇都没读明白了 能不能说说这道题如何定位和解题的思维QAQ
解答：
点赞2
阅读1000
提问：
解答：
点赞0
阅读953
问个问题
注册太麻烦？点这里查看免费答疑吧！
博币不足
加"GMAT小百科"小智微信
直接送200
