North American back bears are shy animals. They are fearful by nature, and will usuallyrun away if they see or hear people. Because of this, it can be difficult for scientists to learnabout these animals. In order to study black bears, researchers from New Jersey, USA, catch bears and usedrugs to help them go to sleep. Researchers then work out the size and the weight of the bear,take blood to test for diseases, remove a tooth and take it to the lab to find out its age. Fromthese studies,researchers want to find out how many bears live in New Jersey, how long theylive, and how many babies theyproduce. But in Minnesota, USA, researchers study bears that are completely awake. The bears knowthe researchers' voices and they are not afraid of die research team. With the help of a few grapes to keep the bears busy, researchers can touch them to check their hearts, look at their teeth, and do other jobs.Researchers can also walk or sit with bears for hours and make videos to learn about their everyday lives. In both places, the main purpose is the same—to make sure there is a healthy population of black bears. But theresearch methods and the kinds of information that researchers, are able to collect are quite different.  小题1:In the first paragraph, we can learn that North American black bears are _______.
|