Hidden Species May Be Surprisingly Common Cryptic species animals that appear identical but are genetically quite distant一may be much more widespread than previously thought. The findings could have major implications in areas ranging from biodiversity estimates and wildlife management,to our understanding of infectious diseases and evolution. Scientists had previously speculated that cryptic species were predominantly found in insects and reptiles,and were more likely to occur in tropical rather than temperate regions. Species that are seemingly widespread and abundant could in reality he many different cryptic species that have low populations and are highly endangered, says Henninger. Until the genetic information of all species. in at least one texon is thoroughly studied, no one will know just how many cryptic species exist. It could be as high. as 30%,Pfenninger says Sampling as many individuals as possible, scientists hope to complete work on all fish and birds in another 5 to 10 years. Once either of these taxonumic groups is completed. Pfenninger says researchers will be able to decide how many cryptic species exist throughout the animal kingdom. The reclassifications are more than an academic exercise: They define populations that have evolved independently of each other and whom genetic differences that have evolved independently of each other and whose genetic differences can have significant consequences. 1,Which of the following about the significance of the research on cryptic species is NOT true? B The results of the research can help the development of biodiversity estimates. D. The results of the research can help our understanding of survival of the fittest. A They occurred in equal numbers in all biogeographical regions C They were likely to be in tropical rather than temperate regions 3, Do scientists know how many cryptic species exist? B Yes. they do. D They will never know the answer. A The WCU are interbreeding those elephants C They are two genetically distant species.
“凡亚比”登陆台湾 将成为今年我国最强台风
高价蓝光影碟超清晰画质纯属骗人?
奥运电影经典台词11句
北京奥运机动车限行措施昨日启动
给你支招:让你躲过“电梯杀手”的17招
绯闻女孩第四季剧透 Chuck是否归来之谜
英皇后人选引热议 卡梅伦力挺卡米拉
欧盟报告称立陶宛为“谋杀之都”
周杰伦与“台湾第一美女主播”亲昵..
北京奥运村迎来首批“村民”
走马观花看美国:体验世界过山车之最
今年过节流行送2012诺亚方舟船票
360度看伦敦 世界最清晰全景图出炉
盘点2011-《时代》年度十大被忽略事件
盖茨基金会支持北京“无烟奥运”
象棋大师头脑发达 双脑并用
麦当劳的奥运“嘉年华”
双语资讯:台湾外海发生6.6级地震
台湾咖啡店标明咖啡因含量卖咖啡
奥运金牌:快乐和忧愁天注定?
盘点2011年全球最“潮”的工作(双语)
资讯英语:公务员考试报名 最火职位4616选1
双语:七旬老妇成世界最年长母亲
孩子开销大怎么办?
双语:七旬 “女巫” 被活活烧死
元宵节传说:点彩灯源于天帝震怒?
漂亮妈妈多生女 美男渐成稀缺品
威廉准新娘订婚白裙网上火热拍卖
双语:中国人均寿命增速有点慢
奥运给北京树起新地标
不限 |
英语教案 |
英语课件 |
英语试题 |
不限 |
不限 |
上册 |
下册 |
不限 |