2021年托福阅读PASSAGE 75 试题及答案

2021年托福阅读PASSAGE 75

试题及答案

PASSAGE 75

Many prehistoric people subsisted as hunters and gatherers. Undoubtedly, game

animals, including some very large species, provided major components of human

diets. An important controversy centering on the question of human effects on

prehistoric wildlife concerns the sudden disappearance of so many species of large

animals at or near the end of the Pleistocene epoch.

Most paleontologists suspect that abrupt changes in climate led to the mass

extinctions. Others,however, have concluded that prehistoric people drove many of

those species to extinction through overhunting. In their "Pleistocene overkill

hypothesis," they cite what seems to be a remarkable coincidence between the arrival

of prehistoric peoples in North and South America and the time during which

mammoths, giant ground sloths, the giant bison, and numerous other large mammals

became extinct.

Perhaps the human species was driving others to extinction long before the dawn of

history. Hunter-gatherers may have contributed to Pleistocene extinctions in more

indirect ways. Besides overhunting, at least three other kinds of effects have been

suggested: direct competition, imbalances between competing species of game

animals, and early agricultural practices. Direct competition may have brought about

the demise of large carnivores such as the saber-toothed cats. These animals simply

may have been unable to compete with the increasingly sophisticated hunting skills

of Pleistocene people.

Human hunters could have caused imbalances among game animals, leading to the

extinctions of species less able to compete. When other predators such as the gray

wolf prey upon large mammals, they generally take high proportions of each year's

crop of young. Some human hunters, in contrast, tend to take the various age-groups of large animals in proportion to their actual occurrence. If such hunters first

competed with the larger predators and then replaced them, they may have allowed

more young to survive each year, gradually increasing the populations of favored

species. As these populations expanded, they in turn may have competed with other

game species for the same environmental niche, forcing the less hunted species into

extinction. This theory, suggests that human hunters played an indirect role in

Pleistocene extinctions by hunting one species more than another.

1. What does the passage mainly discuss?

(A) The effects of human activities on prehistoric wildlife

(B) The origins of the hunter-gatherer way of life

(C) The diets of large animals of the Pleistocene epoch

(D) The change in climate at the end of the Pleistocene epoch

2. The word "Undoubtedly" in line 1 is closest in meaning to

(A) occasionally

(B) unexpectedly

(C) previously

(D) certainly

3. The word "components" in line 2 is closest in meaning to

(A) parts

(B) problems

(C) changes

(D) varieties

4. Which of the following is mentioned as supporting the Pleistocene overkill

hypothesis?

(A) Many of the animals that became extinct were quite large.

(B) Humans migrated into certain regions around the time that major extinctions

occurred.

(C) There is evidence that new species were arriving in areas inhabited by humans.

(D) Humans began to keep and care for certain animals.

5. The word "Besides" in line 14 is closest in meaning to

(A) caused by

(B) whereas

(C) in addition to

(D) in favor of

6. The author mentions saber-toothed cats in line 17 as an example of a

carnivore that

(A) became extinct before the Pleistocene epoch

(B) was unusually large for its time

(C) was not able to compete with humans

(D) caused the extinction of several species

7. The word "they" in line 22 refers to

(A) human hunters

(B) game animals

(C) other predators

(D) large mammals

8. According to the passage , what is one difference between the hunting done

by some humans and the hunting done by gray wolves?

(A) Some humans hunt more frequently than gray wolves.

(B) Gray wolves hunt in larger groups than some humans.

(C) Some humans can hunt larger animals than gray wolves can hunt.

(D) Some humans prey on animals of all ages, but gray wolves concentrate their

efforts on young

9. The word "favored" in line 26 is closest in meaning to

(A) large

(B) escaping

(C) preferred

(D) local

10. According to the passage , the imbalances discussed in paragraph 3 may

have resulted from

(A) the effect of climate changes on large game animals

(B) large animals moving into a new environment

(C) humans hunting some species more than others

(D) older animals not being able to compete with younger animals

ANSWER KEYS

PASSAGE 75 ADABC CCDCC