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Now scientists believe that global warming affects hibernating animals, causing them to wake up earlier. While this may seem a little concern, it is in fact a significant environmental problem. The shortened hibernation period could actually lead to significant declines in the population of several species.
Some of the first concrete evidence of the phenomenon came from Colorado, where researchers at the Rocky Mountain Biological lab have been observing marmot(旱獭)hibernation behavior since the 1970s. In the early days of their studies, marmots generally hibernated several weeks into the month of May. Nowadays, however, temperatures in the area have risen by 2. 5 degrees Fahrenheit, and the marmots wake up about a month earlier.
