经济学人下载:蜂群崩坏症候群 蜂群崩坏

Science and technology
科学技术

Colony collapse disorder
蜂群崩坏症候群

Bee off
蜂群崩坏

A possible explanation of why beehives sometimes vanish
有可能解释清楚为什么蜂群有时会突然死亡

HONEYBEES are sensitive creatures.
蜜蜂是一种敏感的生物，

From time to time a hive simply gives up the ghost and vanishes.
时不时就有蜂巢凭空消失。

Colony collapse disorder, as this phenomenon is known, has been getting worse since 2006.
这种现象被称为蜂群崩坏症候群，自2006年开始就愈发严重了。

Some beekeepers worry that it may make their trade impossible, and could even have an effect on agriculture.
有些养蜂人担心这会使得他们的生意难以维持下去，甚至会对农业造成影响。

Since many crops rely on bees to pollinate them.
因为很多庄稼依靠蜜蜂授粉。

Climate change, habitat destruction, pesticides and disease have all been suggested as possible causes.
气候变化、栖息地被破坏、杀虫剂的使用和疾病都是可能的原因。但

Nothing, though, has been proved.
是尚无一个得到证实。

But the latest idea, reported in Naturwissenschaften by Jeff Pettis of the Bee Research Laboratory in Beltsville, Maryland,
最新的想法刊登在《自然科学》杂志上，作者是位于马里兰贝茨维尔的蜜蜂研究实验室的杰夫佩蒂斯，

suggests that this may be because more than one factor is involved.
他说可能的原因也许不止一个。

Dr Pettis and his colleagues knew from previous reports that exposure to a pesticide,
佩蒂斯博士和他的同事们从之前的报告中得知接触到一种杀虫剂,

called imidacloprid has a bad effect on honeybees' ability to learn things，
这种叫做吡虫啉的会影响蜜蜂的学习能力，

and wondered whether it might be causing other, less noticeable, damage.
他们怀疑这种杀虫剂还对蜜蜂造成其他不太明显的伤害。

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,
要死亡的蜂群有一个共同点，就是蜂群里所含的寄生虫和病原体的种类和数量比一般蜂群的都多，

they wondered in particular whether it might be weakening the insects'immune systems,
他们特别怀疑是吡虫啉削弱了蜜蜂的免疫系统，

and thus allowing infections to spread through a hive.
进而使得传染病在蜂巢里扩散开来。

To find out, they gave 20 hives protein food in the other ten it was 20 ppb.
为了证实猜测，佩蒂斯博士和同事们把加了吡虫啉的蛋白食物喂给20个蜂群。

Previous experiments have shown that neither dose perceptibly harms bees.
之前的实验显示这两种剂量对蜜蜂都没有明显的伤害。

A further ten hives were given unspiked food as a control.
还有10个蜂群作为控制组，喂给它们的食物未加杀虫剂。

Then, when the young bees emerged a few weeks later,
几周后，幼蜂出生，

Dr Pettis collected them and fed them with spores of a fungal parasite called Nosema.
佩蒂斯博士把它们收集起来，喂给它们真菌寄生虫小孢子虫的孢子。

Twelve days later, he killed them and estimated the extent of their infestation.
12天后，他把这些幼蜂都杀了并测量它们体内感染程度。

Both of the groups that had been exposed to imidacloprid harboured an average of 700,000 parasite spores in each bee.
接触到吡虫啉的两组蜜蜂每只体内寄生孢子的平均数量是700000。

Bees from the control colonies, by contrast, harboured fewer than 200,000 spores in their bodies.
与之对比，控制组的蜜蜂体内则含不到200000个孢子。

The insecticide, in other words, was exposing bees to infestation,
换句话说，这种杀虫剂使蜜蜂更容易受到感染，

and thus to a much greater chance of dying prematurely.
因而早亡的几率更大。

Whether this is actually the reason for colonies collapsing remains to be determined.
至于这是不是就是蜂群崩坏症候症的真正原因还有待进一步证实。

But it is a plausible hypothesis, and is likely to get beekeepers buzzing with interest.
但是它的确是一个说得通的假设，养蜂人也会对此很感兴趣。