為什么斑馬身上有條紋？

Why Do Zebras Have Stripes？

For many animals， camouflage is an important part of survival. A leopards spotted coat and a polar bears white fur help them blend into their respective environments.

But a zebras bold stripes cant help to disguise it in its natural habitat， the open plains. The zebras bold markings can also help to conceal it. In 1844， naturalist Francis Galton pointed out that stripes can help disguise zebras in the dim， grayish light of an African night. Fifty years later， an artist named Abbot Thayer suggested that stripes could help actually change the way a predator sees a zebra.

The zebras bold markings draw the viewers attention to the stripes themselves， not the shape of the animal. So when a predator looks at a zebra， it sees stripes first， and then the zebra. This split second of recognition gives the fleet-footed zebra a chance to escape.

To other zebras in the herd， the flash of stripes they see when one zebra starts to flee from an approaching lion is a “follow me” signal. Like the white flash of a deers tail， it alerts the entire herd to danger. The approaching lion， on the other hand， often loses his initial target in the confusing mass of moving stripes.

Stripes also allow young zebras in search of a meal to identify their mothers. And adult zebras use stripes to recognize members of their own species.

對于很多動(dòng)物來說，偽裝是生存的重要部分。獵豹的花斑和北極熊的白毛都能幫助它們?nèi)谌敫髯缘纳姝h(huán)境當(dāng)中。

斑馬醒目的條紋卻不能幫助它們?nèi)诤系阶约核畹拈_闊平原當(dāng)中。但是斑馬醒目的斑紋也可以把自己隱藏起來。1844年，自然學(xué)家Francis Galton指出，這些條紋可以幫助斑馬在非洲夜晚那灰暗的微光下偽裝自己。五十年后，一位名叫Abbot Thayer的藝術(shù)家提出這些條紋可能會改變獵食者看到的斑馬形象。

斑馬醒目的斑紋把觀察者的注意力吸引到斑紋本身，而不是動(dòng)物的輪廓。因此，當(dāng)獵食動(dòng)物看斑馬時(shí)，它先注意到的是斑紋，然后才是斑馬。這不到一秒的時(shí)間給了動(dòng)作很快的斑馬逃脫的機(jī)會。

當(dāng)一匹斑馬開始逃避正在靠近的獅子時(shí)，斑馬群中的其他斑馬看到的閃動(dòng)條紋對它們來說意味著“跟我來”的信號。跟鹿尾后閃動(dòng)的白點(diǎn)一樣，這對整群動(dòng)物來說是危險(xiǎn)警報(bào)。而另一方面，對正在靠近的獅子來說，在一團(tuán)令人眼花繚亂的移動(dòng)斑紋之中經(jīng)常會找不到最初定位的目標(biāo)。

斑紋也可以幫助正在找食的小斑馬辨別自己的母親。成年斑馬則可以通過斑紋來識別自己的同類。