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Narrator:Listen to part of a lecture in a biology class.
獨白:聽下面一段生物學課上的演講。
Professor:Almost all animals have some way of regulating their body temperature;
教授:幾乎所有動物都有某種調節身體溫度的方法；
otherwise they wouldn't survive extreme hot or cold conditions.
不然他們就不能在極其炎熱或寒冷的條件下生存:
sweating, panting, swimming to cooler or warmer water; ducking into somewhere cool like a burrow or a hole under a rock; these are just a few.
流汗，喘氣，或是游到更涼或更溫的水域里；闖入冰冷的地洞或巖石下的洞穴。這些只是少數例子而已。
And that's body is colder or warmer than the surrounding environment, because it's a microclimate.
在這些環境中，他們的身體溫度要比周遭的環境低或高，因為這就是小氣候。
A microclimate is a group of climate conditions that affect the localized area, weather features like temperature, wind, moisture and so on.
所謂小氣候，指的是一組氣候條件，這些條件可能會影響到局部區域，那里的氣候特征，包括氣溫，風，和濕度等等。
And when I say localized, I mean really localized, because microclimates can be, as the name suggests, pretty small, even less than a square meter.
而當我說到局部，我指的是就那么小部分，因為小氣候就像其名字表明的一樣，很小，甚至小于一平方米。
And microclimates are affected by huge number of other variables.
而小氣候會受到其他大量可變因素所影響。
Obviously weather conditions in the surrounding areas are a factor.
很明顯周圍區域的氣候條件就是因素之一。
But other aspects of the location like, um… the elevation of the land, the plant life nearby, and so on, have a substantial effect on microclimates.
而該區域的其他方面因素，像，額，土地平面上身，周圍的植物等等，會對小氣候區域起到極大的影響。
And of course the human development in the area, eh, a road will affect a nearby microclimate.
當然，還有該區域的人類開發活動，呃，建一條公路也會影響到周邊的小氣候。
It's also interesting to know that microclimates thither or near each other can have very different conditions.
同時有趣的是，那里的小氣候或相鄰的兩種小氣候的環境條件都會大相徑庭。
In the forest for example, there can be a number of very different microclimates close to each other, because of all the variables I just mentioned.
比如，森林里就有大量的相鄰小氣候區域，其環境截然不同，這就是因為我所提到的各種不同的可變因素。
Student:So how does a hole in the ground, a burrow, stay cool in a hot climate?
學生:那么地下的洞穴，地洞，是怎么在炎熱的氣候中保持清涼的呢？
Professor:Well, since cold air sinks, and these spots are shaded, they are usually much cooler than the surrounding area.
教授:嗯，由于冷空氣沉降，這些地方就會處在遮陰中，所以溫度經常比周邊環境的要低。
And these spots are so important because many animals rely on microclimates to regulate their body temperature.
而這些地區很是重要，因為很多動物就是依靠小氣候來調節其身體溫度的。
Hmm, for instance, there is a species of squirrel, in the Western part of the United States that can get really hot when they were out foraging for food.
比如說，有一種松鼠，棲息在美國西部地區，當他們外出覓食的時候，身體會變得很熱。
So they need a way to cool down. So what'd they do?
所以他們需要找到降溫的方法。那么他們怎么做呢？
They go back to their own burrow.
他們會回到自己的地洞中。
Once they get there, their body temperatures decrease very, very quickly. The trip to the burrow prevents the squirrel from getting too hot.
一旦他們回到地洞，他們身體溫度就會急速下降。到達地洞的過程可以防止松鼠身體變熱。
Student:But squirrels are mammals, right?
學生:但松鼠是哺乳動物不是嗎？
I thought mammals regulate their temperature internally.
我想哺乳動物會自身調節身體溫度。
Professor:Mammals do have the ability to regulate their body temperature, but not all can do it to the same degree, or even the same way.
教授:哺乳動物有能力調節自己的體溫，但不是都能達到同樣的水平，或以同樣的方式。
Like when you walk outside on a hot day, you perspire, and your body cools itself down, a classic example of how mammal regulates its own body temperature.
就像在炎熱的天氣你在外面走，就會流汗，你的身體會慢慢冷下來，這是一個經典的例子，證明了哺乳動物是怎么調節自身體溫的。
But one challenge that squirrels face, well many small mammals do, is that because of their size, sweating would make them lose too much moisture. They dehydrate.
但是松鼠面臨的一個挑戰，額，很多小型哺乳動物都會面臨的，就是由于體型問題，一流汗就會流失太多水分。
But on the other hand, their small size allows them to fit into very tiny spaces.
他們會脫水。但另一方面講，正因為他們體型小，才允許他們能喜愛狹窄的空間中活動。
So for small mammals, microclimates can make a big difference.
所以對于小型的哺乳動物來講，小氣候有大不同。
They rely on microclimates for survival.
他們依靠小氣候而得以生存。
Student:So cold blood animals, like reptiles, they can't control their own body temperature, so I can image the effect of microclimate would have on them.
學生:那么冷血動物呢，像爬行類動物，他們不能控制自己的體溫，所以我能想象得出小氣候對他們的影響。
Professor:Yes, many reptile insects rely on microclimates to control their body temperature.
教授:是的。很多爬行類昆蟲都依靠小氣候來控制自己的體溫。
A lot of reptiles use burrows or stay under rocks to cool down.
很多爬行動物通過待在洞穴中或巖石底下來減低體溫。
Of course with reptiles, it's a balancing act.
當然對于爬行動物來說，這是一種平衡的方式。
Staying in the heat for too long can lead to problems, but staying in the cold can do the same.
在熱環境中待過長時間的話會出現問題，而在冷環境中也是。
So reptiles have to be really precise about where they spend their time, even how they position their bodies.
所以爬行類動物不得不分毫不差得把握在某種環境中的時間，甚至是他們身體位置要怎么擺放的問題。
And when I say they're precise, I mean it.
當我說分毫不差的時候，我是真的意思就是分毫不差。
some snakes will search out a place under rocks of a specific thickness, because too thin a rock doesn't keep them cool enough, and too thick a rock will cause them to get too cold.
某些蛇類會在某一塊厚度適宜的石頭下尋找落腳的地方，因為如果石頭厚度不夠，蛇便不能保持低體溫，而太厚了會讓他們體溫太低。
That level of precision is critical to the snake for maintaining its body temperature.
這種精確的厚度對于蛇保持自己體溫是至關重要的。
And even microscopic organisms rely on microclimates for survival.
甚至是微生物也要依賴小氣候生存。
Think about this, decomposing leaves create heat that warms the soil; the warm soil in turn affects the growth, the conditions of organisms there.
想想，葉子分解會產生熱量使突然變暖；溫熱的土壤反過來會影響到微生物的生長和環境。
And those organisms then affect the rate of decomposition of the leaves.
而這些微生物也會影響到葉子分解的速率。
So a microclimate can be something so small and so easily to disturbed that even a tiny change can have a big impact.
所以一種小氣候可能是很小的區域，很容易受到干擾，一點點改變會造成大影響。
If someone on a hike knocks a couple of rocks over, they could be unwittingly destroying a microclimate that an animal or organism relies on.
如果有人在遠足旅行的時候敲擊到某些巖石，他們就可能無意間破壞了某一種動物或微生物賴以生存的小氣候區域環境。
