問題詳情

III. Reading Comprehension: Choose the best answer for the question（20 分）Part A.Perhaps no destination has inspired more great naturalists than Brazil.Charles Darwin first made landfall at Bahia in 1832; Alfred Russel Wallaceand Henry Walter Bates arrived at Pará in 1848 and Fritz Müller in 1852.Wallace roamed the Amazon for four years and the indefatigable Bates for11.While Darwin and Wallace would conceive of the theory of evolution bynatural selection, its acceptance was aided by Bates and Müller. And thanksto Bates and Müller, no creatures contributed more to the early growth ofevolutionary science than butterflies.Bates noticed species whose wing patterns resemble those of otherbutterfly families in the area. In puzzling this out, he realized that harmlessbutterflies were mimicking noxious species that were unpalatable to birdsand lizards, and therefore not attacked by predators.A few years after Darwin published “On the Origin of Species,” Batessuggested that this sort of mimicry—now called “Batesian”—was proof ofthe principle of natural selection.Müller crucially observed that unpalatable butterflies were alsomimicking other species of unpalatable butterflies. If they were alreadyunpalatable, he wondered, what added advantage was there to mimickingother species? It dawned on him that unpalatable mimics would enjoystrength in numbers: Their unpalatability had to be learned by predators, andspecies would share the cost of those lessons, whereas a uniquely patternedunpalatable species would bear the full cost.Natural selection thus explained why different species’ wing patternswould converge. But how were such similar but complex wing color patternsgenerated by different species? The answer eluded scientists for nearly 150years, until an international team of researchers recently revealed mimicry’sinnermost secrets.There were two ways in which what is still called “Müllerian mimicry”would evolve: Either each species independently evolved mutations that ledto very similar wing patterns, or patterning genes were exchanged amongspecies. By analyzing the DNA sequences in two mimicking Heliconiusspecies in South America, researchers could determine that each species hadindependently evolved up to 20 different patterns. But in more closely relatedmimicking species, they found that color-controlling genes had beenexchanged.It is astonishing that so many patterns could be independently generated andreplicated in different species. And it is surprising to have species swappinggenes. After all, the inability to breed successfully with other groups has longbeen an operational definition of species. Even if such interspecies matingsare rare, a gene that confers a strong advantage, like mimicry, can spreadquickly through a population.
51. Which statement of the four naturalists mentioned in the passage is NOTcorrect?
(A) Darwin wrote “On the Origin of Species.”
(B) Wallace embraced the idea of evolution by natural selection.
(C) Bates stayed in the Amazon for the longest time among the four.
(D) Müller discovered how butterflies generated their wing color patterns.

參考答案

答案：C
難度：適中0.533333
統計：A(0),B(2),C(8),D(3),E(0)

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