提醒：点这里加小编微信（领取免费资料、获取最新资讯、解决考教师一切疑问！）
Betty, a new Caledonian crow living in a research lab, was hungry. She could see a piece of meat at the bottom of a test tube, but she could not reach it. In the wild, crows use twigs to dig into trees to get insects. There were no twigs in Betty，s cage, but that didn，t stop the hungry crow. She found a straight piece of wire that someone had left in the cage. She picked it up with her beak. Then she stuck the wire under some sticky tape that was also in her cage, and bent the wire. Finally, she used her new tool to remove the piece of meat from the test tube. The scientists in the lab watched in amazement as she popped the piece of meat in her mouth. They knew crows could use tools, but could they make them? That was something new. Clearly crows were more intelligent than they had thought.
In another show of intelligence, a group of crows in a Tokyo suburb have learned a new way to get lunch. They fly over intersections and drop nuts in front of cars. The cars drive over the nuts, and the crows wait for the light to change. When the light turns red, the cautious crows fly down and eat the nuts without fear of being run over. The behavior has become widespread as more and more crows teach it to others. After observing crow behavior in the laboratory and in the wild, scientists now believe that the birds are not just acting instinctively. They believe that crows have the intellectual capacity to plan, solve problems, and teach new behaviors to others.
These stories of crow genius attracted the attention of a writer named Joshua Klein. To find out if crows could be trained, Klein designed an experiment. He built a vending machine for crows. Inside the machine were nuts. He knew that crows were attracted to shiny things, so he put coins on the ground around the machine. At first, the crows just picked up the coins. By chance, a few crows dropped some coins into the machine and were rewarded with a nut. Soon, the crows appeared to understand the relationship among the coins, the machine, and the nuts. Klein，s experiment, along with other research, shows how well crows can adapt to new challenges.
提醒：点这里加小编微信（领取免费资料、获取最新资讯、解决考教师一切疑问！）
