老托福阅读Passage41真题答案.docx

智课网TOEFL备考资料老托福阅读Passage 41真题答案 摘要： 老托福阅读100篇是初期托福阅读训练者拿来练手找感觉的好材料。核心价值在于它是最接近真题思维方式的题目。而托福阅读的思维方式就是托福阅读的出题方式，只有掌握了这种思维方式，才有可能在做题之前，预测到新托福阅读题的出题形式和特点，为找答案节省时间。 虽然 托福 阅读考试发生了改革，但是很多老托福的材料也非常适合用来练习 新托福 ，比如老 托福阅读 100篇，这份材料对于新手备考是非常不错的材料，因为其难度不高，而且内容接近新托福，小编推荐一篇老托福阅读的真题，附有原文及答案，希望对大家有所帮助。 Biological diversity has become widely recognized as a critical conservation issue only in the past two decades. The rapid destruction of the tropical rain forests, which are the ecosystems with the highest known species diversity on Earth, has awakened people to the importance and fragility of biological diversity. The high rate of species extinctions in these environments is jolting, but it is important to recognize the significance of biological diversity in all ecosystems. As the human population continues to expand, it will negatively affect one after another of Earths ecosystems. In terrestrial ecosystems and in fringe marine ecosystems (such as wetlands), the most common problem is habitat destruction. In most situations, the result is irreversible. Now humans are beginning to destroy marine ecosystems through other types of activities, such as disposal and run off of poisonous waste; in less than two centuries, by significantly reducing the variety of species on Earth, they have unraveled cons of evolution and irrevocably redirected its course. Certainly, there have been periods in Earths history when mass extinctions have occurred. The extinction of the dinosaurs was caused by some physical event, either climatic or cosmic. There have also been less dramatic extinctions, as when natural competition between species reached an extreme conclusion. Only .01 percent of the species that have lived on Earth have survived to the present, and it was largely chance that determined which species survived and which died out. However, nothing has ever equaled the magnitude and speed with which the human species is altering the physical and chemical world and demolishing the environment