When most people think about animals， they imagine furry little cow-eyed creatures innocently plucking leaves from trees or bugs from the ground for nourishment. However， many people are shocked to learn that， just as in human life， there's an incredible part to the animal world. If you thought you knew a lot about animal behavior， the following unbelievable but true animal facts may cause your jaw to drop.

大多數(shù)人一想到動(dòng)物，就會(huì)想到各種毛茸茸的小家伙，它們長(zhǎng)著牛眼似的眼睛，毫無(wú)惡意地從樹(shù)上扯下葉子或在地上找蟲(chóng)子來(lái)美餐一頓。然而，很多人卻驚訝地發(fā)現(xiàn)，如同人類生活一樣，動(dòng)物世界也有不可思議的一面。如果你認(rèn)為自己對(duì)動(dòng)物的行為已經(jīng)了解頗多，那下面這些令人難以置信但又真實(shí)存在的動(dòng)物奇事恐怕仍會(huì)讓你驚愕不已。

Cows Are More Deadly than Sharks

For most people， few things evoke fear like the image of a great white shark. A combination of popular culture movies and widespread media stories concerning shark attacks has worked in concert1） to create a universal fear of these toothy eating machines. However， the dangers posed by sharks to humans are overstated. In fact， sharks kill only ten people each year. By contrast， you're ten times more likely to die under the clumsy2） feet of ordinary cows who fatally trample around 100 people every 12 months.

Headless Roaches Can Live up to Nine Days

Most people are familiar with the notion that roaches are hearty， durable pests. Anyone who has ever been plagued3） by a roach problem knows just how resilient4） these ugly little creatures can be. Many are surprised at just how adept5） roaches are at survival and reproduction. Roaches are able to live up to nine days without a head because their brains are located deep within their body cavities6）.

奶牛比鯊魚(yú)更致命

對(duì)大多數(shù)人來(lái)說(shuō)，大白鯊的形象喚起的恐懼感幾乎無(wú)物可比。關(guān)于鯊魚(yú)襲擊人類的大眾文化電影和廣泛的媒體報(bào)道一直齊頭并進(jìn)，激發(fā)了人們對(duì)這些多齒類“食人機(jī)器”的普遍的恐懼感?？墒牵忯~(yú)對(duì)人類構(gòu)成的威脅被夸大了。事實(shí)上，每年只有10個(gè)人會(huì)命喪鯊魚(yú)之口，相比之下，你命喪牛蹄下的幾率是前者的十倍，每年被普通奶牛亂蹄踩死的有約100人。

無(wú)頭蟑螂能活九天

大多數(shù)人都很熟悉這一概念：蟑螂是精力充沛、耐力超強(qiáng)的害蟲(chóng)。但凡被蟑螂困擾過(guò)的人都知道這些外貌丑陋的“小強(qiáng)”生命力有多頑強(qiáng)。蟑螂嫻熟的生存和繁殖能力也著實(shí)讓很多人驚訝不已。由于大腦位于體腔深處，蟑螂沒(méi)有頭之后還能存活九天。

A Wolf's Howl Does Not Echo

Wolves hunt in coordinated packs7）， so long-distance communication is critical to a successful kill. However， wolves hunt in mountainous areas， so their howling is left vulnerable to echoes that can distort their ability to communicate. To combat this， wolves howl at a frequency that will not echo. This allows them to confirm the exact location of their hunting partners， which helps them to ambush unsuspecting prey.

Half of All Orangutans Have Broken Bones

Orangutans seem to drift through branches from tree to tree with relative ease. However， almost all orangutans suffer serious falls at least a few times in their lives. Proving this is the fact that 50 percent of adult orangutans have fractured8） bones somewhere in their body.

Some Clams Are Transgendered

Every single clam is born into the world a male. To combat this， clams have developed the ability to change their gender from male to female. However， before the clam makes this serious adjustment， it has to be sure， as once the change is made， it's irreversible9）.

Woodpeckers Are Soft-Headed

Woodpeckers bash10） their heads against wood about 20 pecks every second， so you'd think they'd need heads made of steel to survive. Instead， the reality is that woodpecker heads are relatively soft. Each bird is born with a soft， sponge-like mass behind its beak11） that absorbs the shock created by pecking.

狼的嚎叫沒(méi)有回聲

狼捕獵時(shí)要成群結(jié)隊(duì)、團(tuán)結(jié)協(xié)作，因此遠(yuǎn)距離溝通對(duì)成功捕獲獵物至關(guān)重要。然而，由于狼在山區(qū)獵食，所以它們的嚎叫聲容易被回聲破壞，而回聲就會(huì)干擾它們彼此之間的溝通。為解決這個(gè)問(wèn)題，狼便以不會(huì)產(chǎn)生回聲的頻率嚎叫。這讓它們可以確定一起獵食的同伴的具體位置，從而有助于它們伏擊毫無(wú)戒備的獵物。

半數(shù)的猩猩都有斷骨

猩猩看上去似乎能較為輕松地從一棵樹(shù)蕩到另一棵樹(shù)，在樹(shù)枝之間隨意穿行。然而，幾乎所有的猩猩一生之中都會(huì)遭受至少幾次嚴(yán)重的摔傷。事實(shí)證明，50%的成年猩猩都在身體某些部位有斷裂的骨頭。

有些蛤蚌是變性的

每一只蛤蚌在來(lái)到這個(gè)世界之初都是雄性的。為了應(yīng)對(duì)這種情況，蛤蚌已經(jīng)進(jìn)化出變性的本領(lǐng)，能從雄性變成雌性。不過(guò)，蛤蚌在做出這一重大改變之前，一定要拿準(zhǔn)主意，因?yàn)樗坏┳冃跃驮僖沧儾换貋?lái)了。

啄木鳥(niǎo)頭部很柔軟

啄木鳥(niǎo)能以每秒約20次的頻率用頭猛擊樹(shù)木，因此，你可能會(huì)認(rèn)為它們得長(zhǎng)個(gè)“鐵頭”才能生存。與此相反，實(shí)際上啄木鳥(niǎo)的頭部較為柔軟。每只啄木鳥(niǎo)的鳥(niǎo)喙根部生來(lái)就裹著一層天然的海綿狀的東西，能夠緩沖它啄木時(shí)產(chǎn)生的沖擊力。

1.in concert： 一齊；協(xié)力

2.clumsy [?kl?mzi] adj. 笨拙的

3.plague [ple?ɡ] vt. 困擾；使煩惱；折磨

4.resilient [r??z?li?nt] adj. 韌性的；病后恢復(fù)能力強(qiáng)的

5.adept [??dept] adj. 熟練的

6.body cavities： 【動(dòng)】體腔

7.pack [p?k] n. （尤指狼或狗的）一群

8.fracture [?fr?kt??（r）] vi. 斷裂；折斷

9.irreversible [??r??v??s?bl] adj. 不可逆轉(zhuǎn)的；不可挽回的

10.bash [b??] vt. 猛擊；猛撞

11.beak [bi?k] n. （鳥(niǎo)的）喙