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Narrator:Listen to part of a lecture in a biology class.
独白:听下面一段生物学课上的演讲。
Professor:Almost all animals have some way of regulating their body temperature;
教授:几乎所有动物都有某种调节身体温度的方法；
otherwise they wouldn't survive extreme hot or cold conditions.
不然他们就不能在极其炎热或寒冷的条件下生存:
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，喘气，或是游到更凉或更温的水域里；闯入冰冷的地洞或岩石下的洞穴。这些只是少数例子而已。
And that's body is colder or warmer than the surrounding environment, because it's a microclimate.
在这些环境中，他们的身体温度要比周遭的环境低或高，因为这就是小气候。
A microclimate is a group of climate conditions that affect the localized area, weather features like temperature, wind, moisture and so on.
所谓小气候，指的是一组气候条件，这些条件可能会影响到局部区域，那里的气候特征，包括气温，风，和湿度等等。
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.
而当我说到局部，我指的是就那么小部分，因为小气候就像其名字表明的一样，很小，甚至小于一平方米。
And microclimates are affected by huge number of other variables.
而小气候会受到其他大量可变因素所影响。
Obviously weather conditions in the surrounding areas are a factor.
很明显周围区域的气候条件就是因素之一。
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.
而该区域的其他方面因素，像，额，土地平面上身，周围的植物等等，会对小气候区域起到极大的影响。
And of course the human development in the area, eh, a road will affect a nearby microclimate.
当然，还有该区域的人类开发活动，呃，建一条公路也会影响到周边的小气候。
It's also interesting to know that microclimates thither or near each other can have very different conditions.
同时有趣的是，那里的小气候或相邻的两种小气候的环境条件都会大相径庭。
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邻小气候区域，其环境截然不同，这就是因为我所提到的各种不同的可变因素。
Student:So how does a hole in the ground, a burrow, stay cool in a hot climate?
学生:那么地下的洞穴，地洞，是怎么在炎热的气候中保持清凉的呢？
Professor:Well, since cold air sinks, and these spots are shaded, they are usually much cooler than the surrounding area.
教授:嗯，由于冷空气沉降，这些地方就会处在遮阴中，所以温度经常比周边环境的要低。
And these spots are so important because many animals rely on microclimates to regulate their body temperature.
而这些地区很是重要，因为很多动物就是依靠小气候来调节其身体温度的。
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.
比如说，有一种松鼠，栖息在美国西部地区，当他们外出觅食的时候，身体会变得很热。
So they need a way to cool down. So what'd they do?
所以他们需要找到降温的方法。那么他们怎么做呢？
They go back to their own burrow.
他们会回到自己的地洞中。
Once they get there, their body temperatures decrease very, very quickly. The trip to the burrow prevents the squirrel from getting too hot.
一旦他们回到地洞，他们身体温度就会急速下降。到达地洞的过程可以防止松鼠身体变热。
Student:But squirrels are mammals, right?
学生:但松鼠是哺乳动物不是吗？
I thought mammals regulate their temperature internally.
我想哺乳动物会自身调节身体温度。
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:哺乳动物有能力调节自己的体温，但不是都能达到同样的水平，或以同样的方式。
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.
就像在炎热的天气你在外面走，就会流汗，你的身体会慢慢冷下来，这是一个经典的例子，证明了哺乳动物是怎么调节自身体温的。
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.
但是松鼠面临的一个挑战，额，很多小型哺乳动物都会面临的，就是由于体型问题，一流汗就会流失太多水分。
But on the other hand, their small size allows them to fit into very tiny spaces.
他们会脱水。但另一方面讲，正因为他们体型小，才允许他们能喜爱狭窄的空间中活动。
So for small mammals, microclimates can make a big difference.
所以对于小型的哺乳动物来讲，小气候有大不同。
They rely on microclimates for survival.
他们依靠小气候而得以生存。
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.
学生:那么冷血动物呢，像爬行类动物，他们不能控制自己的体温，所以我能想象得出小气候对他们的影响。
Professor:Yes, many reptile insects rely on microclimates to control their body temperature.
教授:是的。很多爬行类昆虫都依靠小气候来控制自己的体温。
A lot of reptiles use burrows or stay under rocks to cool down.
很多爬行动物通过待在洞穴中或岩石底下来减低体温。
Of course with reptiles, it's a balancing act.
当然对于爬行动物来说，这是一种平衡的方式。
Staying in the heat for too long can lead to problems, but staying in the cold can do the same.
在热环境中待过长时间的话会出现问题，而在冷环境中也是。
So reptiles have to be really precise about where they spend their time, even how they position their bodies.
所以爬行类动物不得不分毫不差得把握在某种环境中的时间，甚至是他们身体位置要怎么摆放的问题。
And when I say they're precise, I mean it.
当我说分毫不差的时候，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.
某些蛇类会在某一块厚度适宜的石头下寻找落脚的地方，因为如果石头厚度不够，蛇便不能保持低体温，而太厚了会让他们体温太低。
That level of precision is critical to the snake for maintaining its body temperature.
这种精确的厚度对于蛇保持自己体温是至关重要的。
And even microscopic organisms rely on microclimates for survival.
甚至是微生物也要依赖小气候生存。
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，叶子分解会产生热量使突然变暖；温热的土壤反过来会影响到微生物的生长和环境。
And those organisms then affect the rate of decomposition of the leaves.
而这些微生物也会影响到叶子分解的速率。
So a microclimate can be something so small and so easily to disturbed that even a tiny change can have a big impact.
所以一种小气候可能是很小的区域，很容易受到干扰，一点点改变会造成大影响。
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.
如果有人在远足旅行的时候敲击到某些岩石，他们就可能无意间破坏了某一种动物或微生物赖以生存的小气候区域环境。
