Of all the continents, the most drastic reduction in wildlife has occurred in North America, where the transition from a rural to a highly industrialized society has been most rapid. Among the victims are birds, mammals, and fish. We will never again see the passenger pigeon or the eastern elk. They have been wiped out. Of many other species, only a few representatives still survive in the wild. The U. S. Department of the Interior has put no fewer than 109 species on the endangered species list. This list includes everything from the timber wolf to the whooping crane. Even the bald eagle, our national symbol, is threatened.
Animals that kill other game for food are called predators. The predators include the wolf, mountain lion, fox, bobcat, and bear. Attack against these animals began with the arrival of the first European settlers, who wished to protect their livestock. Eventually, a reward was offered to hunters for every predator that was killed. This reward is called a bounty.Ironically, the Federal government is the chief founder of predator-control programs.
The settlers also brought in their Old World fears and superstitions concerning predators. Whether preying on livestock or not, predators were shot on sight. This attitude continues to this day for coyotes, eagles, foxes, mountain lions, and bobcats, and is largely responsible for placing the eastern timber wolf, grizzly bear, and bald eagle on the endangered species list.
Yet every animal, including the predator, has its place in natures grand design. Predators help maintain the health of their prey speciesby eliminating the diseased, young, old and injured. Predators like the mountain lion and the wolf help to keep the deer herds healthy. Occasional loss of livestock must be weighed against the good these animals do in maintaining the balance of nature.
1. In North America, the number of wild animals has reduced most greatly mainly 112 because_______.
A. the birds, mammals and fish there are most predators
B. the development there has been at the highest pace
C. only a few species still live in the world
D. many species have been put on the endangered species list
2. The first European settlers killed predators chiefly in order to_______.
A. eat their meat
B. protect themselves
C. please the Federal government
D. protect their livestock
3. Some animal species are in danger of disappearing altogether from the earth as a result of_______.
A. peoples superstitious attitude
B. peoples dislike of some animals, such as bald eagle
C. peoples hunting games
D. the self-killing of the predators
4. Bounty hunters are people who_______.
A. take care of wilderness areas
B. preserve our wildlife
C. kill meat-eating animals for money
D. work in the fund of predator-control programs
5. According to the writer, even if the meat-eating animals sometimes caused losses of livestock, man should_______.
A. estimate the value of predators
B. compare the losses with the benefits of predators
C. keep the balance of nature
D. raise more livestock
1. B 2. D 3. A 4. C 5. B
我们日常会做的十大怪事的科学解释(下)
科学家发现一类地行星“百分之百”适宜生命存活
世界之旅:Miami, Florida, U
胆小者勿入! 盘点十大让人惊悚的有关幽灵的照片
阿凡达发光树或成真 未来可代替路灯
全球城市生活质量排行榜出炉 维也纳品质最高
美国男子发明理发头盔 20秒瞬间剃头
研究发现:地球再变暖或使蜥蜴进化成恐龙
智能手机有名无实 功能仅10%被用
想住白金汉宫? 每人每晚一万英镑!
研究发现:音乐品味可决定恋爱成败
研究显示:男性沉迷手机将面临不育风险
阿富汗塑料衣男孩美梦成真:获梅西签名球衣
维基泄密创始人钟爱的“地下数据中心”
科技前沿:Droid:iPhone真正的竞争对手
小行星撞地球或使人类变成"吸血鬼"
探索发现:科学家发现奇特系外"钻石"行星群
日本机器人司仪主持婚礼(图)
[科技前沿]4G热潮:看一眼现实吧
10款创意独特的鼠标设计 定会让你大开眼界
阿根廷小海豚被热情游客玩死在沙滩上
[科技前沿]气候问题上,气候专家究竟扮演怎样的角色?
科技前沿:微软呕心打造Win 7避免重蹈Vista覆辙
感人!印度母亲在女儿车祸地点自发维护交通
吸入式食物机诞生 吃饭不再用牙齿
吃巧克力能治咳嗽?英国研发止咳新药
二十年长发织成一件背心
日本发明体温镜 照镜子就知是否发烧
听到别人打电话为何心烦 科学家找出答案
超人象棋大师 大脑两侧竟能同时运转
不限 |
英语教案 |
英语课件 |
英语试题 |
不限 |
不限 |
上册 |
下册 |
不限 |