Part IV Cloze (10%)
For some behaviors in animals, there is little proof for strong genetic (基因的) determination. Not only are there many environmental and historical changes in behavior patterns, 56 we also know that some of them are passed on from one generation to the 57 . They are “cultural”.
The term “culture” here 58 social traditions. One 59 of animal culture is the well-studied food-handling behavior of the group of Japanese monkeys living 60 the small, wooded island of Koshima. These monkeys 61 to live in the forests, but Japanese researchers came and started to feed them by 62 sweet potatoes on the sandy beach. Soon, the monkeys began to leave the forests and 63 the sweet potatoes on the beach. About a year 64 the feeding started, a young female monkey was 65 to wash the potatoes in a nearby river. She actively and successfully 66 the sand on them. Within the next few years, potato-washing spread 67 the group, and the practice was carried 68 from the river to the sea. 69 potato-washing in the sea, several other habits 70 with feeding on the sandy beach are now well established in the monkey group. The habits are passed from mothers and other group members to the babies.
Japanese monkeys are not the only animals to have 71 their behaviors. In many cities and towns, European red foxes have successfully changed some of their behaviors in 72 to get used to their new city life over a short period of time. Obviously, this is not the 73 of the selection of genes. The same is 74 of common racoons (浣熊) in America. The course of the evolution (进化) of behavior cannot be adequately described and understood without 75 “culture” as an active factor. The cultural factor affects the selection of genes.
