2024年3月16日发(作者：)

2019年托福考试考场模拟训练题及答案5

Butterflies are among the most extensively studied

insects — it is estimated that 90 percent of the world's

species have scientific names. As a consequence, they are

perhaps the best group of insects for examining patterns of

terrestrial biotic diversity and distribution. Butterflies

also have a favorable image with the general public. Hence,

they are an excellent group for communicating information on

science and conservation issues such as diversity.

Perhaps the aspect of butterfly diversity that has

received the most attention over the past century is the

striking difference in species richness between tropical and

temperate regions. For example, in 1875 one biologist pointed

out the diversity of butterflies in the Amazon when he

mentioned that about 700 species were found within an hour's

walk, whereas the total number found on the British islands

did not exceed 66, and the whole of Europe supported only 321.

This early comparison of tropical and temperate butterfly

richness has been well confirmed.

A general theory of diversity would have to predict not

only this difference between temperate and tropical zones,

but also patterns within each region, and how these patterns

vary among different animal and plant groups. However, for

butterflies, variation of species richness within temperate

or tropical regions, rather man between them, is poorly

understood. Indeed, comparisons of numbers of species among

the Amazon basin, tropical Asia, and Africa are still mostly

"personal communication" citations, even for vertebrates. In

other words, unlike comparison between temperate and tropical

areas, these patterns are still in the documentation phase.

In documenting geographical variation in butterfly

diversity, some arbitrary, practical decisions are made.

Diversity, number of species, and species richness are used

synonymously; little is known about the evenness of butterfly

distribution. The New World butterflies make up the

preponderance of examples because they are the most familiar

species. It is hoped that by focusing on them, the errors

generated by imperfect and incomplete taxonomy will be

minimized.

1. Which aspect of butterflies does the passage mainly

discuss?

(A) Their physical characteristics

(B) Their names

(C) Their adaptation to different habitats

(D) Their variety

2. The word "consequence" in line 2 is closest in

meaning to

(A) result

(B) explanation

(C) analysis

(D) requirement

3. Butterflies are a good example for communicating

information about conservation issues because they

(A) are simple in structure

(B) are viewed positively by people

(C) have been given scientific names

(D) are found mainly in temperate climates

4. The word "striking引人注目的" in line 8 is closest in

meaning to

(A) physical

(B) confusing

(C) noticeable

(D) successful

5. The word "exceed超过" in line 11 is closest in

meaning to

(A) locate

(B) allow

(C) go beyond

(D) come close to

6. All of the following are mentioned as being important

parts of a general theory of diversity EXCEPT

(A) differences between temperate and tropical zones

(B) patterns of distribution of species in each region