英语听力精选进阶版 10441（在线收听）

Now, have you ever wondered why koalas hug trees? And apparently, according to a new scientific study it is to stay cool.That discovery was made by researchers from the University of Melbourne who were looking at how koalas regulate their body temperature.

大家有没有想过考拉为什么爱抱树？一项新的科学研究表明，考拉抱树是为了凉快。这一发现是由墨尔本大学的研究人员提出的，他们研究了考拉调节体温的方式。

And one of my students Natalie Briscoe, her PHD was focused on this question in terms of the koala. And one of the questions we want to ask about the koala is, do they use behavior at all to regulate their temperature, are they able to choose places in their trees that make them a bit more comfortable.

娜塔莉·布里斯科是我的一个学生，她在博士期间研究的重点是和考拉有关的一个问题，也是我们都好奇的问题，即考拉调节体温是否要做出一些专门举动？它们是否能在树上选择舒适一点的位置？

And how did you go about finding this out?

那么，你们是怎么得出这一发现的呢？

Well, initially we went about this by putting a little weather station on a very long pole and lifting that weather station right up next to the koalas that we had radio transmitters on, and at the same time going around to other random places in their habitat and measuring the conditions in the trees of those locations. But what Natalie noticed was that the koalas in the hot weather would come down and will go to the thicker trunks. And they would flop onto those trunks and drop them limbs there. And we couldn't quite understand why they were doing that, but she also sought to measure the tree trunk temperatures and we found that they are actually quite a bit cool than the air. And then we took a special kind of camera that takes pictures of heat and tells us the temperature of every service in the picture. And it was so obvious once we got those pictures back. What the koalas were doing? They were putting their bottoms into the trees and dumping all their excess heating to the tree.

刚开始，我们在长竿上安装了小型气象站，举到考拉身边，在考拉身上也安装了无线电发射器。同时，随机检测考拉生活区域其他树木的状况。但是娜塔莉注意到，在炎热天气下，考拉会从树上爬下来，选择更粗的树干，跳上去，抱住这些树干。我们刚开始不太理解它们的做法，但是娜塔莉检测到了树枝的温度，我们发现树枝的温度其实稍稍低于气温。然后，我们选用特殊照相机，拍下热量的照片，显示出各种读数。有了照片就一目了然了。考拉的身体紧贴树木是为了把多余的热量传给树木。

And were you surprised by what you found because it's known or presumably zoologists know that the fur on the stomach of the koalas is a lot thinner than it is elsewhere.

你们对这一发现感到吃惊吗？因为我们知道或者说动物学家知道，考拉腹部的皮毛要比其他部位薄得多。

Yeah, well, we knew that and we thought, well, maybe they, I guess one idea was that they just expose that during the hot weather so that heat comes out their chests into the air. What we didn't realize was how much cooler the tree trunks were than the air temperature. That wasn't obvious to us. It was obvious when we looked at the trees with the special camera, but it wasn't before that. And then it made a whole lot of sense. And it's really surprised a lot of biologists.

是的，我们知道。可能大家会认为，炎热天气下考拉会把胸前的皮毛暴露在空气重，从而释放热量。但这个观点忽略了树干温度要低于空气温度这一事实。我们开始也没注意到这一点，直到使用相机观察树木才发现，之前是不明显的。使用相机后才恍然大悟。这着实让许多生物学家吃惊。

And it's always eucalyptus trees, is it?

考拉抱的树总是桉树吗？

No, it's not. And not all eucalyptus trees is good as each other for this purpose, so we measure a whole, a few different species of eucalypts in their habitat where we did the study and also another kind of tree called acacia. And it turned out that the acacia was actually the best one. But they don't eat the leaves of the acacia trees, they only eat the leaves of the eucalypt trees.

不是的。不是所有桉树都适合考拉，所以我们在研究基地检测了考拉生存环境中几种不同的桉树类型。另一种树名叫刺槐，其实刺槐是考拉的最佳选择。但是它们不吃刺槐树叶，只吃桉树叶。