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托福TPO/Official 65 Lec1听力原答案解析-音频翻译【新东方在线】

Listen to part of the lecture in a biology class.

直到大约30年前，科学界一致认为恐龙是冷血动物，

Until about 30 years ago, scientific opinion was pretty much unanimous in thinking that dinosaurs were cold-blooded creatures,

而不是像哺乳动物和鸟类那样的恒温动物。

and not warm blooded like mammals and birds.

这些术语：冷血和恒温动物是什么意思呢?

What are these terms cold- and warm-blooded mean?

嗯，它们是不精确的术语，有点不准确，但是为了一致性，我会继续使用它们。

Well, they are imprecise terms, a little bit inaccurate, but for the sake of consistency, I’ll continue to use them.

恒温动物，或者从技术上说是吸热动物，是利用自身的新陈代谢来维持相对较高的、通常恒定的体温的动物。

Warm-blooded animals, or technically, endothermic animals, are animals that use their own metabolism to maintain a relatively high, generally constant body temperature.

它们自己产生热量，而冷血动物，呃，技术上称为变温动物，

They generate their own heat, whereas cold-blooded animals, uh, technically called endothermic animals,

冷血动物主要依靠环境来调节体温。

cold-blooded animals rely on the environment primarily to regulate their body temperature.

它们的体温会随周围的温度变化很大。

And their body temperature can actually vary a great deal depending on the temperature surrounding them.

现在，就像我所说的，哺乳动物和鸟类是恒温动物，

Now, as I said, mammals and birds are warm-blooded creatures, 

我们是哺乳动物，这一点你们很熟悉,你们知道的，你们的身体一直保持几乎相同的温度

and we being mammals, you’re familiar with, you know, your body stays pretty much the same temperature all the time,

而如果你见过，比如说，你们知道的蛇或蜥蜴，他们在岩石上晒太阳，

whereas if you’ve ever seen, say, snakes or lizards you know, basking in the sun on the rock

你可以看到冷血生物的特征，它利用环境来帮助调节体温。

you can see the characteristic feature of a cold-blooded creature that is using the environment to help regulate its body temperature.

就像我说的，直到大约30年前，恐龙，因为它们看起来最像爬行动物，被认为是冷血动物。

As I said, until about 30 years ago, dinosaurs were, because they seem to most closely resemble reptiles, they were thought to be cold-blooded.

大约30年前，一些科学家开始提出恐龙实际上可能是恒温动物的可能性。

Then about 30 years ago a number of scientists began to suggest the possibility that dinosaurs might in fact be warm-blooded.

这是非常令人兴奋的，原因有很多。

This was very exciting for a variety of reasons.

恒温动物和我们更接近。他们更活跃。他们移动得更快。与冷血动物相比，它们可以生活在更广泛的环境中。

Warm-blooded creatures are closer to us. They are more active. They move faster. They can live in a wider range of environments than cold-blooded creatures.

所以很多科学家都支持恐龙是恒温。

So a lot of scientists kind of got on this bandwagon for warm-blooded dinosaurs.

但不幸的是，很多恐龙可能是恒温动物的证据都是间接的。

But unfortunately, a lot of the evidence for dinosaurs possibly being warm-blooded is indirect.

证据之一是，恐龙的化石遗迹表明，某些种类的恐龙有羽毛。

Among the pieces of evidence is that the fossilized remains of dinosaurs have shown that certain kinds of dinosaurs had feathers.

鸟类的羽毛，除了帮助某些鸟类飞翔之外，它们的主要功能之一是充当绝缘体。

Now, feathers in birds, one of their main functions, apart from helping certain birds to fly, is that they are an insulator.

它们可以保存体温，所以通过类推，一些人认为，好吧，如果它们是有羽毛的恐龙，也许它们有羽毛是为了保暖。

They preserve body heat, so by analogy, some people are argued, well, ok, if they were feathered dinosaurs, maybe they had feathers for insulation.

另一个间接证据是，一些恐龙，嗯，一些恐龙遗骸在今天的北极气候地区被发现，

Another piece of indirect evidence is that some dinosaurs, uh, well, some dinosaur remains have been found in areas,

事实上，恐龙生活在那里的时候，那里的气候可能非常寒冷。

latitudes that today have arctic climates and might in fact had very cold climates at the time that the dinosaurs were living there.

在北极的气候下，冷血动物很难发挥作用。

It’s hard to function as a cold-blooded creature in an arctic climate.

不幸的是，我们没有确切的气候信息。

Unfortunately, we don’t have exact climate information.

只有证据表明这些地区可能和现在一样寒冷。

It’s only been suggested that these areas might have been as cold as they are today.

所以，这并不是，你知道的，支持恐龙是温血动物的有力论据。

So again, this is not, you know, not a knockdown argument in favor of dinosaurs being warm-blooded.

温血理论的另一个论据与恐龙的解剖结构以及它们与温血动物的相似性有关。

Another argument for the warm-blooded theory has to do with looking at the anatomy of dinosaurs and at the similarities with warm-blooded animals.

如果你看看现在的世界，嗯，让我们看看，今天任何用两条腿走路的动物都是温血动物。

If you look at what’s around today, well, let’s see, today anything that walks on two legs is warm-blooded.

这适用于人类和其他一些灵长类动物，还有像鸵鸟这样的鸟类，明白吗?

That goes for humans and some other primates, and birds like the ostrich, okay?

只有温血动物，比如鸵鸟，才有直立的姿势。

Only warm-blooded creatures, you know, like ostriches, have upright posture.

好吧，恐龙是恒温动物的支持者说，看看恐龙，有些恐龙也有直立的姿势。

Alright, so proponents of the idea that dinosaurs were warm-blooded say, well, look at dinosaurs, some of them had upright posture too.

巧合吗?他们说不是，这些两足恐龙也是恒温动物。

Coincidence? They say no, these two-legged dinosaurs were warm-blooded too.

但另一方面，据我们所知，恐龙缺乏一种叫做呼吸鼻甲的身体结构。为什么这很重要呢?

Okay, but on the other hand, as far as we can tell, dinosaurs lacked a body structure called the respiratory turbinate. Why is that significant?

呼吸鼻甲是鼻腔内复杂的结构。

Respiratory turbinate are these complicated structures inside the nasal cavity.

它们与软组织相连，它们的功能是当空气穿过这些复杂的卷曲通道时，进来的空气被加热了

They are aligned with soft tissue and their function is that as the air passes through these complicated kinds of curlicue passages, air coming in is warmed up

so that warm-blooded creature isn’t shocked by..

它的肺部不会受到直接从外部吸入的冷空气的影响，因为冷空气会扰乱它的内部温度。

Its lungs aren’t shocked by receiving cold air directly from the outside, which would really disturb its internal temperature.

所以除非有其他我们不知道的机制，恐龙似乎缺乏所有现存温血动物的这一重要特征。

So unless there are some other mechanism that we don’t know about, it seems that these, that dinosaurs lacked this vital feature of all existing warm-blooded animals.

There is evidence that some dinosaurs had feathers. According to the professor, why does this support the theory that dinosaurs were warm-blooded?

What does the professor imply about regions that now have arctic climates?

Why does the professor mention ostriches?

What is the professor’s opinion of the theory that dinosaurs were warm-blooded?

What does the professor imply when she says this:

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