當(dāng)蜜蜂被困在水里時，它們會自己制造波浪，然后“沖浪”到安全的地方

當(dāng)蜜蜂被困在水里時，它們會自己制造波浪，然后“沖浪”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.

蜜蜂和我們一樣需要水。一只蜜蜂可能會飛幾英里去尋找一個好的水源，既可以用來喝水，也可以用來調(diào)節(jié)蜂房的溫度。然而，有時，一只口渴的蜜蜂得到的東西比它預(yù)料的要多，蜜蜂最終不是喝到水，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.

這對蜜蜂來說比聽起來更糟糕。蜜蜂不會游泳，當(dāng)它們的翅膀變濕以后，它們也不能飛了。但一項新的研究表明，蜜蜂還有另一個不太明顯的選擇來拯救自己:沖浪。

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.

這個發(fā)現(xiàn)始于一次幸運的意外。當(dāng)研究工程師克里斯·盧走過加州理工學(xué)院的校園時，他經(jīng)過加州理工學(xué)院的米利肯池塘，那是因為噴泉已經(jīng)關(guān)閉。盧武鉉看到一只蜜蜂擱淺在水里，因為是中午，太陽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產(chǎn)生的波浪的陰影。

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.

當(dāng)蜜蜂在水中嗡嗡作響時，盧武鉉意識到陰影顯示了它翅膀激起的波浪的振幅，以及一個翅膀的波浪與另一個翅膀的波浪相撞時產(chǎn)生的干涉圖案。

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.

回到實驗室，盧武鉉重現(xiàn)了他在米利肯池塘看到的情況。他和他的導(dǎo)師，加州理工學(xué)院航空和生物工程教授Morteza Gharib一起，把一只蜜蜂放在一鍋平靜的水中，然后從上面用濾過的光照射它，在平底鍋的底部投下陰影。他們對33只蜜蜂進(jìn)行了實驗，但每次只進(jìn)行幾分鐘，然后給每只蜜蜂恢復(fù)的時間。

Surfing to survive

沖浪生存

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動的，而是在入水時向下彎曲，再拉回水面時向上彎曲。研究人員解釋說，拉的動作產(chǎn)生推力，而推的動作是恢復(fù)動作。

"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."

盧武鉉解釋說:“水比空氣重三個數(shù)量級，這就是為什么它能困住蜜蜂。”“但重量也使它有助于推進(jìn)。”

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.

這項技術(shù)有一些限制，因為蜜蜂顯然不能產(chǎn)生足夠的力量把它們的身體從水里舉起來。它可以推動它們前進(jìn)，而不是原地亂飛，這可能足以到達(dá)水邊，然后它們可以爬出來飛走。但這種行為對蜜蜂來說比飛行更累人，盧武鉉估計，它們只能堅持10分鐘左右，然后就會累壞，所以逃跑的機(jī)會可能有限。

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.

盧武鉉補充說，這種行為在其他昆蟲中從未被記錄過，這可能是蜜蜂特有的適應(yīng)性。這項研究的重點是蜜蜂，但未來的研究可能會調(diào)查它是否也被其他蜜蜂物種，甚至可能是其他有翼昆蟲使用。任何有助于我們更好地了解蜜蜂的方法都是值得努力的，因為蜜蜂具有重要的生態(tài)價值，而且近年來它們的數(shù)量普遍減少——這個問題困擾著許多野生物種和蜜蜂。

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.

作為工程師，盧武鉉和加里布也將這一發(fā)現(xiàn)視為生物模擬技術(shù)的機(jī)遇，他們已經(jīng)開始將其應(yīng)用到機(jī)器人研究中。他們正在開發(fā)一種小型機(jī)器人，它可以像擱淺的蜜蜂一樣在水面上移動，他們設(shè)想這項技術(shù)最終會被飛行和游泳的機(jī)器人使用。