Why Woodpeckers Never Get a Concussion啄木鳥為什么不會得腦震蕩？

A strong hit to the head will normally give you a concussion. Woodpeckers， however， strike their beaks into trees thousands of times a day and are perfectly fine.

We used to think that a woodpeckers skull worked as a kind of safety helmet which absorbed the shocks. A study by Sam Van Wassenbergh， a researcher at the University of Antwerp in Belgium， proved that this “common sense” was in fact false.

Van Wassenbergh and his colleagues argued that， if a woodpeckers head absorbed the force， it would not be able to strike the tree with enough force.

“If the beak absorbed much of its own impact， the unfortunate bird would have to pound even harder，” they said in their paper. In other words， if the theory were true， the woodpecker would have to peck even harder to compensate for both the shock-absorbing qualities of the sponge-like bone inside its skull as well as the density of the wood.

頭部受到重擊通常會造成腦震蕩。然而，啄木鳥每天用喙啄樹上千遍，卻仍安然無恙。

我們過去認為啄木鳥的頭骨像是某種安全頭盔，可以吸收沖擊。比利時安特衛(wèi)普大學的研究人員山姆·范·瓦森伯格發(fā)布了一項研究，證明這種“普遍看法”實際上是錯誤的。

范·瓦森伯格及其同事認為，如果啄木鳥靠頭部吸收了撞擊帶來的沖擊力，那么它就無法以足夠的力道啄樹。

范·瓦森伯格團隊在論文中寫到：“如果啄木鳥通過喙吸收了大部分對自己的沖擊力，那么這只不幸的鳥將不得不更加用力地撞擊?！睋Q句話說，如果“安全頭盔”理論是正確的，受啄木鳥頭骨內(nèi)海綿狀骨頭減震特性和木材密度的影響，啄木鳥將不得不更加用力啄樹去補償緩沖掉的力。

The scientists recorded four different kinds of woodpeckers in zoos as they were pecking. The team used data from their high-speed recordings to build digital models of the woodpeckers. Van Wassenbergh described the woodpeckers motion as “a hammer hitting wood” since their movement appeared rigid and focused.

The research suggested that woodpeckers dont have any shock-absorbing device or the ability to reduce the amount of force. Although they are without “helmets”， the team claimed that the woodpeckers tiny size and weight protect them.

A woodpeckers brain is about 700 times smaller than that of a human. “Smaller animals can withstand higher decelerations. Think about a fly that hits a window and then just flies back again，” Van Wassenbergh said. “So that is why even the hardest hits we observed are not expected to cause any concussion.”

研究人員記錄下動物園里四種不同啄木鳥啄食的情景，利用高速視頻的數(shù)據(jù)，建立起啄木鳥的數(shù)字模型。因為啄木鳥的動作看起來僵硬而專注，范·瓦森伯格將其描述為“錘子鑿木頭”。

研究表明，啄木鳥沒有任何減震器和減少沖擊力的能力。不過研究團隊表示，啄木鳥雖然沒有“頭盔”，但它們微小的體型和較輕的體重對自身起到了保護作用。

啄木鳥的大腦比人類的大腦小約700倍?！拜^小的動物可以承受較高的減速。試想一只蒼蠅撞到窗戶，然后又飛了回來?！狈丁ね呱裾f，“所以，這就是哪怕我們觀察到的最嚴重的撞擊，也不會給啄木鳥造成任何腦震蕩的原因?！?/p>

Word Bank

skull /sk?l/ n. 顱骨；頭（蓋）骨

pound /pa?nd/ v. 連續(xù)砰砰地猛擊

She pounded him with her fists.

density /'dens?ti/ n. 密度

claim /kle?m/ v. 宣稱；聲稱；斷言

I dont claim to be an expert.

withstand /w??'st?nd/ v. 承受；經(jīng)受住

The walls can withstand high winds.