二、英翻中【25 分】 Honeybees are sensitive creatures. From time to time a hive simply vanishes. What has been brought into scientists’ attention is that colony collapse disorder, as this phenomenon is known, has been getting worse since 2006. Some beekeepers worry that what has been happening with the disappearance of beehives may make their trade impossible, and could even have an effect on agriculture—since many crops rely on bees to pollinate them. Climate change, habitat destruction, pesticides and disease have all been suggested as possible causes. Nothing, though, has been proved. But the latest research, reported in Naturwissenschaften by Dr. Jeff Pettis of the Bee Research Laboratory in Maryland, suggests that this may be because more than one factor is involved.
Dr. Pettis and his colleagues knew from previous reports that exposure to a pesticide called imidacloprid has a bad effect on honeybees' ability to learn things and wondered whether it might be causing other, less noticeable, damage. Since one thing common to colonies that go on to collapse seems to be a greater variety and higher load of parasites and pathogens than other colonies, they wondered in particular whether it might be weakening the insects' immune systems, and thus allowing infections to spread through a hive.