当蜜蜂被困在水里时，它们会自己制造波浪，然后“冲浪”到安全的地方

当蜜蜂被困在水里时，它们会自己制造波浪，然后“冲浪”到安全的地方

Bees need water just like the rest of us. A honeybee might fly several miles to find a good water source, both for drinking and to help regulate the temperature of her hive. Sometimes, though, a thirsty honeybee gets more than she bargained for, and instead of water ending up in the bee, the bee ends up in the water.

蜜蜂和我们一样需要水。一只蜜蜂可能会飞几英里去寻找一个好的水源，既可以用来喝水，也可以用来调节蜂房的温度。然而，有时，一只口渴的蜜蜂得到的东西比它预料的要多，蜜蜂最终不是喝到水，而是落入水中。

Honeybees can't fly with water on their wings, but they can generate tiny waves and 'surf' on them. (Photo: Wattlebird/Shutterstock)

That's worse for the bee than it might sound. Honeybees can't swim, and when their wings are wet, they can't fly, either. But as a new study reveals, honeybees do have another, less obvious option to save themselves from drowning: surfing.

这对蜜蜂来说比听起来更糟糕。蜜蜂不会游泳，当它们的翅膀变湿以后，它们也不能飞了。但一项新的研究表明，蜜蜂还有另一个不太明显的选择来拯救自己:冲浪。

This discovery started with a lucky accident. As research engineer Chris Roh was walking through the California Institute of Technology campus, he passed by Caltech's Millikan Pond, which was still because the fountain had been turned off. Roh saw a honeybee stranded in the water, and since it was midday, the sun cast shadows of the bee directly onto the bottom of the pool. What really caught his eye, though, were the shadows of the waves created by the bee's wings.

这个发现始于一次幸运的意外。当研究工程师克里斯·卢走过加州理工学院的校园时，他经过加州理工学院的米利肯池塘，那是因为喷泉已经关闭。卢武铉看到一只蜜蜂搁浅在水里，因为是中午，太阳把蜜蜂的影子直接投射到池底。然而，真正引起他注意的是蜜蜂翅膀所产生的波浪的阴影。

As the bee buzzed in the water, Roh realized the shadows showed the amplitude of the waves kicked up by its wings, along with the interference pattern created as waves from one wing collided with waves from the other.

当蜜蜂在水中嗡嗡作响时，卢武铉意识到阴影显示了它翅膀激起的波浪的振幅，以及一个翅膀的波浪与另一个翅膀的波浪相撞时产生的干涉图案。

Back in the lab, Roh recreated the conditions he'd seen in Millikan Pond. With his advisor, Caltech aeronautic and bioengineering professor Morteza Gharib, he placed a single bee in a pan of still water, then shone filtered light on it from above, casting shadows on the bottom of the pan. They did this with 33 individual bees, but only for a few minutes at a time, and then gave each bee time to recover afterward.

回到实验室，卢武铉重现了他在米利肯池塘看到的情况。他和他的导师，加州理工学院航空和生物工程教授Morteza Gharib一起，把一只蜜蜂放在一锅平静的水中，然后从上面用滤过的光照射它，在平底锅的底部投下阴影。他们对33只蜜蜂进行了实验，但每次只进行几分钟，然后给每只蜜蜂恢复的时间。

Surfing to survive

冲浪生存

Hydrofoiling can't lift a bee out of the water, but it can propel her to the water's edge, where she then climbs to safety. (Photo: Chris Roh and Mory Gharib/Caltech)

Instead of flapping flatly, honeybee wings curve downward as they push into water, then curve upward as they pull back to the surface. The pulling motion generates thrust, the researchers explain, while the pushing motion is a recovery stroke.

蜜蜂的翅膀不是平拍动的，而是在入水时向下弯曲，再拉回水面时向上弯曲。研究人员解释说，拉的动作产生推力，而推的动作是恢复动作。

"Water is three orders of magnitude heavier than air, which is why it traps bees," Roh explains. "But that weight is what also makes it useful for propulsion."

卢武铉解释说:“水比空气重三个数量级，这就是为什么它能困住蜜蜂。”“但重量也使它有助于推进。”

Honeybees store water in their honey stomachs and take it back to their hive. (Photo: UrbanRadim/Shutterstock)

There are some limitations to this technique, since the bees apparently can't generate enough force to lift their bodies out of the water. It can propel them forward instead of just flailing in place, though, which might be enough to reach the water's edge, where they can then crawl out and fly away. But the behavior is more tiring for bees than flying, and Roh estimates they can only keep it up for about 10 minutes before wearing out, so the opportunity to escape may be limited.

这项技术有一些限制，因为蜜蜂显然不能产生足够的力量把它们的身体从水里举起来。它可以推动它们前进，而不是原地乱飞，这可能足以到达水边，然后它们可以爬出来飞走。但这种行为对蜜蜂来说比飞行更累人，卢武铉估计，它们只能坚持10分钟左右，然后就会累坏，所以逃跑的机会可能有限。

This behavior has never been documented in other insects, Roh adds, and it might be a unique adaptation in bees. This study focused on honeybees, but future research could investigate whether it's also used by other bee species, or possibly even other winged insects. Anything that helps us better understand bees is likely worth the effort, given the ecological importance of bees and their widespread declines in recent years — a problem plaguing many wild species as well as honeybees.

卢武铉补充说，这种行为在其他昆虫中从未被记录过，这可能是蜜蜂特有的适应性。这项研究的重点是蜜蜂，但未来的研究可能会调查它是否也被其他蜜蜂物种，甚至可能是其他有翼昆虫使用。任何有助于我们更好地了解蜜蜂的方法都是值得努力的，因为蜜蜂具有重要的生态价值，而且近年来它们的数量普遍减少——这个问题困扰着许多野生物种和蜜蜂。

As engineers, Roh and Gharib also see this discovery as an opportunity for biomimicry, and they've already begun applying it to their robotics research, according to a news release from Caltech. They're developing a small robot that can move on the surface of water like a stranded honeybee, and they envision the technique eventually being used by robots that can fly and swim.

作为工程师，卢武铉和加里布也将这一发现视为生物模拟技术的机遇，他们已经开始将其应用到机器人研究中。他们正在开发一种小型机器人，它可以像搁浅的蜜蜂一样在水面上移动，他们设想这项技术最终会被飞行和游泳的机器人使用。