在线英语听力室_免费在线英语听力学习网站

 　　Chimps¹ show other chimps how to use tools. My roommate showed me some tricks to make better scrambled² eggs. Group members teaching each other is called cultural transmission. And a study finds that a cultural transmission is behind the spread of hunting techniques among humpback whales off New England. The research is in the Journal Science. It's called loptail feeding. A humpback whale slaps the surface of the water with its tail. The resulting bubbles pen in prey³ fish, which the whales gobble up. Researchers first sought lobtail feeding in 1980. Within 30 years, 37 percent of the observed humpback had picked up the techiques. To create mathematical models for the spreading of lobtail feeding, researchers used 27 years of data from wild-watching boats in the Gulf⁴ of Maine. And the model that included cultural transmission as a factor, best match the data. Those models assumed that humpback whales that spent more time with lobtail feeders were more likely to pick up the methods themselves. Clearly, whales are capable of sophisticated social interactions-and we've only seen the tip of the tail.