練習：
1. Which of the following about the significance of the research on cryptic species is NOT true?
A The results of the research can help the development of many other researchareas.
B The restllts of the research can help the development of biodiversityestimates.
C The results of the research can help our understanding of infectious diseaseevolution.
D The results of the research can help our understanding of “survival of thefittest.”
2. What was scientists’ understanding of cryptic species?
A They occurred in equal numbers in all biogeographical regions.
B They were mostly found in insects find reptiles.
C They were likely to be in tropical rather than temperate regions.
D Both B and C.
3. Do scientists know how many cryptic species exist?
A Not yet.
B Yes，they do.
C They will know the answer in another one or two years;
D They will never know the answer.
4. Which of the following about the African bush elephant and the African elephant is true?
A The WCU are interbreeding those elephants.
B They are interbreeding species.
C They are two genetically distant species.
D They depend on each other for survival.
5. People were confused in their attempts to control malaria in Europe in the early1900s，because scientists
A identified only one mosquito species instead of six species.
B thought only three mosquito species transmitted disease.
C thought there was only one mosquito species.
D did not know what species was being studied.
答案與題解：
1. D 短文的第一段第二句的大意是，研究結果為廣泛的研究領域提供啟示，包括生物多樣性研究，還能幫助我們理解傳染疾病及其演變。所以，選項A、B、C都是正確的，它們不是答案。選項D的“適者生存”的內容文章中沒有提及，因此是本題的答案。
2. D 短文的第二段第二句描述的是科學家目前的研究結果，第三段描述的是科學家在這之前對于cryptic species的理解。本題用的是過去式，問的是過去的狀況，因此，答案在第三段中，B和C是答案，所以D是正確選擇。
3. A 第三段和第五段提供了答案。第三段的倒數第二句中的Until...no one will know just how many cryptic species exist.其意思就是人們目前還不了解。第五段的最后一句也說明了研究者目前對此尚未了解。
4. C 答案在第六段中。該段舉了非洲大象為例，說明什么是cryptic species.第六段的句子“A 2001 study found the elephants were actually two genetically distinct，non- interbreeding spemes”是選擇C的依據。選項A不對，the WCU并沒有雜交繁殖這兩種象。選項B不對，短文說這兩種象是非雜交物種。選項D的內容短文中找不到。
5. A 短文最后一段告訴我們，由于對蚊子種類不了解，20世紀初期瘧疾曾肆虐歐洲，最終，科學家才了解到蚊子這一物種不是由一個種類而是由六個種類組成。所以，應該選擇A.