問題詳情
Question 1-9The canopy ,the upper level of the trees in the rain forest, holds a plethora of climbingmammals of moderately large size, which may include monkeys, cats, civets, andporcupines. Smaller species, including such rodents as mice and small squirrels ,are notline as prevalent overall in high tropical canopies as they are in most habitats globally.(5) Small mammals, being warm blooded, suffer hardship in the exposed and turbulentenvironment of the uppermost trees. Because a small body has more surface area per unitof weight than a large one of similar shape, it gains or loses heat more swiftly. Thus, inthe trees, where shelter from heat and cold may be scarce and conditions may fluctuate, asmall mammal may have trouble maintaining its body temperature.(10) Small size makes it easy to scramble among twigs and branches in the canopy forinsects, flowers, or fruit, but small mammals are surpassed, in the competition for food,by large ones that have their own tactics for browsing among food-rich twigs. The weightof a gibbon (a small ape) hanging below a branch arches the terminal leaves down so thatfruit-bearing foliage drops toward the gibbon’s face. Walking or leaping species of a(15) similar or even larger size access the outer twigs either by snapping off and retrieving thewhole branch or by clutching stiff branches with the feet or tail and plucking food withtheir hands.Small climbing animals may reach twigs readily, but it is harder for them than for largeclimbing animals to cross the wide gaps from on tree crown to the next that typify the(20) high canopy. A macaque or gibbon can hurl itself farther than a mouse can: it can achievea running start, and it can more effectively use a branch as a springboard, even bouncingon a climb several times before jumping. The forward movement of a small animal isseriously reduced by the air friction against the relatively large surface area of its body.Finally, for the many small mammals that supplement their insect diet with fruits or seeds(25) an inability to span open gaps between tree crowns may be problematic, since trees thatyield these foods can be sparse.
【題組】1. The passage answers which of the followingquestions?
(A) How is the rain forest different from other habitats?
(B) How does an animal’s body size influencean animal’s need for food?
(C) Why does the rain forest provide anunusual variety of food for animals?
(D) Why do large animals tend to dominate theupper canopy of the rain forest?
參考答案
答案：D
難度：適中0.5
統計：A(0),B(3),C(0),D(3),E(0)