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A camel can travel hundreds of miles, over several days, without stopping to drink.
駱駝可以行走數百英里，并在幾天之內也不用喝水。
On today's Moment of Science, we'll learn how camels survive the dry desert.
在今天的科學一刻中，我們將會學習駱駝是怎樣在干燥的沙漠中生存的。
Let's start with the hump.
我們先從駝峰說起，
Contrary to what you might have heard, camels do not store extrawater here.
和你所聽說的不一樣的是，駱駝并沒有儲存多余的水在這里。
The hump stores fat, providing energy for their long, desert trek.
駝峰積聚著脂肪，為它們長距離的沙漠旅行提供能量。
This fat, however,can help keep a camel from getting thirsty.
然而就是這些脂肪，可以幫助駱駝止渴。
As the fat is burned, water is produced as one of thebyproducts.
水就是這些脂肪燃燒所產生的副產物之一。
This extra water enters the camel's bloodstream to add to its water supply.
這些額外的水進入駱駝的血液，增加其水分的供應。
Camels conserve water by not sweating as much as we do.
駱駝不像我們那樣出汗，這樣也可以儲存水分。
A camel's metabolism lowers at night,making its body temperature much lower than a human's.
駱駝的新陳代謝到晚上就會降低，讓它的體溫低于人類。
Because we sweat to cool ourselves off,starting with a lower body temperature means less need to sweat.
出汗可以冷卻我們自己，因此如果體溫較低的話，對汗水的需求也會比較少。
Camels are also covered withheavy fur which keeps the daytime heat out.
駱駝同樣覆蓋著厚重的皮毛，這些皮毛可以防止白天的熱量進入體內。
Because it's so good at keeping its cool, a camel cantravel a long way without sweating very much.
正因為駱駝如此擅長保持其身體的冷卻，所以它可以走很長時間，卻不會流很多汗。
Camels are also good at maintaining their blood volume.
駱駝同樣也很擅長保持它們的血容量。
Once we humans lose about twelvepercent of our body's water, our blood becomes too thick to work properly.
我們人類一旦流失了身體百分之十二的水分，血液就會變得太濃稠以至于不能正常工作。
A camel's blood,however, stays more or less consistent, allowing the camel to lose up to twenty-five percent of itsweight by dehydration.
可是駱駝的血液，總是可以堅持到讓其脫水到其重量的百分之二十五。
Another thing that helps a camel conserve water is its nasal passages.
另一個有助于駱駝儲存水的東西就是鼻腔。
When we exhale, we loosea lot of water vapor, as any fogged up car window will prove.
當我們呼氣的時候，我們會流失許多水蒸汽，被霧氣模糊的車窗可以證明這一點。
Camels have extra dry nasalpassages which actually recondense the water out of each breath, allowing much less to escape.
駱駝有額外的干燥鼻腔，可以凝聚每次呼吸的水分，讓水分的蒸發的變少。
As you can see, there is no single explanation for a camel's desert survival abilities.
就如你所見，沒有關于駱駝沙漠生存能力的單一解釋。
Instead, a cameldraws on a whole range of adaptations.
相反地，駱駝有一系列的適應能力。
