60秒科学:大象果真怕蚂蚁

We all know that elephants aren’t really scared of mice. But a new study shows that they’re really not crazy about something even smaller: ants. In fact, elephants dislike ants so much that they avoid acacia trees that harbor the tiny, six-legged nectar-suckers.

On the savanna¹, acacia trees growing in regions that get a lot of elephant traffic tend to get eaten. But researchers noticed that one species of acacia was not much bothered by elephants. And that the untouched acacia was a favorite ant habitat.

So the scientists stripped the ant-covered acacia of their bodyguard² bugs³, and sure enough, the elephants chowed down. In addition, when the insects were placed on previously⁴ ant-free acacias, the elephants took a pass.

But how can teeny, tiny ants repel⁵ a big old elephant, which is, after all, about a billion times more massive? The answer is in the trunk. Or rather, not in the trunk. Because, as you can probably relate, elephants really hate to have ants up their noses.

The research is published in the journal Current Biology.  And it suggests that adding ants could help preserve wooded areas on the savanna. Because ants will ruin any picnic, even for pachyderms.—Karen Hopkin
 

1 savanna   

n.大草原

参考例句：

• The savanna is also the home of meat-eaters--the lion,leopard,and hyena who feed on the grasseaters.大草原也是食肉动物的家乡--狮子、豹、鬣狗--它们都是以草食动物维持生命的。
• They sped upon velvet wheels across an exhilarant savanna.他们的马车轻捷地穿过一片令人赏心悦目的大草原。

2 bodyguard   

n.护卫，保镖

参考例句：

• She has to have an armed bodyguard wherever she goes.她不管到哪儿都得有带武器的保镖跟从。
• The big guy standing at his side may be his bodyguard.站在他身旁的那个大个子可能是他的保镖。

3 bugs   

adj.疯狂的，发疯的n.窃听器( bug的名词复数 )；病菌；虫子；[计算机]（制作软件程序所产生的意料不到的）错误

参考例句：

• All programs have bugs and need endless refinement. 所有的程序都有漏洞，都需要不断改进。 来自《简明英汉词典》
• The sacks of rice were swarming with bugs. 一袋袋的米里长满了虫子。 来自《简明英汉词典》

4 previously   

adv.以前，先前（地）

参考例句：

• The bicycle tyre blew out at a previously damaged point.自行车胎在以前损坏过的地方又爆开了。
• Let me digress for a moment and explain what had happened previously.让我岔开一会儿，解释原先发生了什么。

5 repel   

v.击退，抵制，拒绝，排斥

参考例句：

• A country must have the will to repel any invader.一个国家得有决心击退任何入侵者。
• Particles with similar electric charges repel each other.电荷同性的分子互相排斥。