2. 外语
  3. COGNITIVE MAPS IN ANIMALS (1) A central hypothesis of animal cognition is that many animals make use of cognitive maps—inter

COGNITIVE MAPS IN ANIMALS (1) A central hypothesis of animal cognition is that many animals make use of cognitive maps—inter

admin2022-08-28  20
问题                                             COGNITIVE MAPS IN ANIMALS
    (1) A central hypothesis of animal cognition is that many animals make use of cognitive maps—internal representations or codes—of the spatial relationships among objects in their surroundings. In a broad sense, most animals that migrate probably have some internal map of the way external objects are arranged.
    (2) The most extensive studies of cognitive maps have been made for animals that exhibit seasonal migration, the regular back-and-forth movement of animals between two geographic areas at particular times of the year. [A] Seasonal migration enables many species to access rich food resources throughout the year and to breed or winter in areas that favor survival. [B] One long-distance traveler is the gray whale. [0] During summer, these giant aquatic mammals feast on small, bottom-dwelling invertebrates that abound in northern oceans. [D] In the fall, they leave their northern feeding grounds and begin a long trip south along the North American coastline. Arriving in warm, shallow lagoons off Baja California (Mexico) in the winter months, they breed, and pregnant females give birth to young before migrating back north. The yearly round-trip, some 20,000 kilometers, is the longest for any mammal.
    (3) Among insects, the monarch butterfly has one of the most remarkable seasonal migrations. During winter, these insects decorate certain trees at the western tip of Cuba, in a few mountain valleys of central Mexico, and at a few sites along the California coast. All monarchs alive at the end of summer fly south to reach their wintering sites. With the onset of spring, monarchs mate at the wintering sites and begin migrating northward. As they arrive at summer destinations, they lay eggs and then die. Two or more generations are produced during the summer, repopulating the United States and southern Canada. With the approach of fall, the summer’s last generation of monarchs flies south to the wintering grounds. They migrate as far as 4,000 kilometers and end up at a specific site, although they have not flown the route before.
    (4) Researchers have found that migrating animals stay on course by using a variety of environmental cues. Gray whales, for instance, seem to use coastal landmarks to pilot their way north and south. Migrating south in the fall, they orient themselves with the North American coastline on their left. Migrating north in the spring, they keep the coast on their right. Whale watchers sometimes see gray whales stick their heads straight up out of the water, perhaps to obtain a visual fix on land. Many birds migrate at night, navigating by the stars the way ancient human soldiers did. In contrast, monarch butterflies migrate during the day, resting in trees and bushes at night; genetic programming may enable them to use the Sun as a compass.
    (5) Navigating by the Sun or by stars requires an ability to keep track of compass direction. Many migrators also must have an internal timing mechanism that compensates for the continuous daily movement of Earth relative to celestial objects. The timing mechanism must also allow for the apparent change in position of celestial objects as the animal moves over its migration route. Almost nothing is known yet about the nature of these timing mechanisms. At least one night-migrating bird, the indigo bunting, seems to avoid the need for a timing mechanism by fixing on the North Star, the one bright star in northern skies that appears almost stationary. Researchers have found that buntings learn a star map and fix on a stationary star when navigating at night.
     (6) Another interesting, and more or less open, question about migration is how birds continue navigating when the Sun or stars are obscured by clouds. There is strong evidence that some birds can orient themselves to Earth’s magnetic field. Magnetite, the iron-containing mineral once used by sailors as a crude compass, is probably involved in sensing the field. The mineral has been found in the heads of pigeons, in the abdomens of bees, and in certain bacteria that orient themselves to a magnetic field. Future research may show that magnetic sensing is a widespread, important part of a complex navigation mechanism in many animals.
Look at the four squares [ ■ ] that indicate where the following sentence could be added to the passage. For a variety of animals, there are two clear purposes for this behavior.
Where would the sentence best fit?
选项
答案A
解析 本题属于插入句子题，需要插入的句子意为“对各种动物而言，这种行为有两个明确的目的”this behavior提示该句的上文已经提及了某种具体行为，而承接该句的下文应该会指出两个目的具体是什么?第2段首句逗号后面的内容讲述了动物的季节性迁徙这一行为。第2句讲到动物的季节性迁徙有两个好处：获得全年充足的食物资源；在有利于其生存的地区繁殖或过冬。根据上述推断分析，题干句子插在第2段第1句和第2句之间逻辑最合理，故选A处。若题干句子插在B处，即第2、3句之间，而第3句开始又提到了新信息——灰鲸，则前后文毫无逻辑关系，行文没有意义，故不选B处。第3—5句的内容是举了灰鲸的例子来证明第2句的观点，三个句子逻辑紧密。且均无法与需要插入的句子合理衔接，故也不宜放在C、D处。
转载请注明原文地址:https://jikaoti.com/ti/6ecYFFFM
0

托福（TOEFL）

相关试题推荐
随机试题
最新回复(0)