A thirsty crow(乌鸦) comes across a bottle of water, but the water level is out of its reach. The bird then drops stones into it to reach the water and start drinking.
"It's just a story," you may think. But new research has found that crows' brains may sometimes be better than those of 6-year-old children.
In a recent experiment, American scientist Corina Logan and her team caught six crows to test them. The crows and children had to choose between two sets of tubes(管子). Both groups had to drop in stones to reach the water.
With the red set, when they dropped a stone into a wide tube, the water level rose in a connected narrow(窄的) tube. The blue set of tubes, however, had no connection between them. Children aged 7 to 10 were able to learn the rule. Children aged 4 to 6, however, failed. Five of the six crows failed the test. But Kitty, a 6-month-old crow, passed it. She put most of the stones into the red tube.
So, could a bird be more clever than a kindergartener? Don't be too quick to say no.
