Endotherms are animals such as modern birdsand mammals that keep their body temperatures constant. For instance, humansare endotherms and maintain an internal temperature of 37℃, no matterwhether the environment is warm or cold. Because dinosaurs were reptiles, andmodern reptiles are not endotherms, it was long assumed that dinosaurs were notendotherms. However, dinosaurs differ in many ways from modern reptiles, andthere is now considerable evidence that dinosaurs were, in fact, endotherms.
恒温动物是指诸如现代鸟类和哺乳动物这种可以保持体温恒定的动物。比如，人是恒温动物，无论环境温度是怎样，体温都维持在37℃。因为恐龙属于爬行动物，而现代的爬行动物都不属于恒温动物，所以长期以来恐龙都被当做是变温动物。然而，恐龙在很多地方都同现在的爬行动物不一致。同时，现在有大量的证据表明恐龙其实是恒温动物。
Polardinosaurs
One reason for believing that dinosaurswere endotherms is that dinosaur fossils have been discovered in Polar Regions.Only animals that can maintain a temperature well above that of the surroundingenvironment could be active in such cold climates.
极地恐龙
主张恐龙属于恒温动物的原因是在极地发现了恐龙。只有能够很好维持体温的动物才能在如此寒冷的地方生存。
Legposition and movement
There is a connection between endothermyand the position and movement of the legs. The physiology of endothermy allowssustained physical activity, such as running. But running is efficient only ifan animal’s legs are positioned underneath its body, not at the body’s side, asthey are for crocodiles and many lizards. The legs of all modern endotherms areunderneath the body, and so were the legs of dinosaurs. This strongly suggeststhat dinosaurs were endotherms.
腿的位置和运动方式
恒温动物和腿的位置及运动方式有一定联系。恒温动物的生理结构允许它们进行持续的物理运动，比如奔跑。但是，只有当腿长在身体的下部而不是两侧的时候才能快速地奔跑，而像鳄鱼或者很多蜥蜴的腿，都是长在身体两侧的。所有现代恒温动物的腿都是长在身体下部的，而恐龙的腿也具有同样的特点。这很有力地说明了恐龙是恒温动物。
Haversiancanals
There is also a connection betweenendothermy and bone structure. The bones of endotherms usually includestructures called Haversian canals. These canals house nerves and blood vesselsthat allow the living animal to grow quickly; and rapid body growth is in facta characteristic of endothermy. The presence of Haversian canals in boneis astrong indicator that the animal is an endotherm, and fossilized bones ofdinosaurs are usually dense with Haversian canals.
哈弗森管
恒温动物和骨结构之间也有相应的关联。很多恒温动物都有一种名为哈弗森管的骨结构。这种哈弗森管可以保护神经和血管以保障动物快速地生长，而快速生长恰恰是恒温动物的一个特征。哈弗森管的存在可以有力的说明该动物属于恒温动物，而恐龙的骨骼化石中常常可以观察到哈弗森管。
托福综合写作阅读部分需要提取的观点是：
- Main point: 恐龙是恒温动物
- Sub point 1: 恐龙的化石在极地发现，而极地只有恒温动物生存，所以恐龙是恒温动物。
- Sub point 2: 恐龙有跟恒温动物一样的腿结构，所以恐龙是恒温动物。(这个是有逻辑漏洞
的，一会在听力部分我再解释)
- Sub point 3: 恐龙跟恒温动物一样的哈弗森管，所以恐龙是恒温动物。
托福综合写作阅读观点抽出方法：
这篇文章的观点抽取上难度不是很大，但是问题的关键是要看到这个论证的逻辑链，而找到的逻辑链有助于我们在听力的时候快速精准地提取有用信息。
分论点一的逻辑是：只有恒温动物能适应极地的寒冷气候，而恐龙能适应，所以恐龙是恒温动物。这个只有让这个逻辑关系合格，所以只能翻过极地的状态和恐龙的状态了，
分论点二的逻辑是：是什么?是“所有现代恒温动物的腿都是长在身体下部的，而恐龙的腿也具有同样的特点”吗?不是的，腿长在身体下部是恒温动物的“必要不充分条件”。段内的逻辑是这样的：腿长在身体下部à可以快跑à可以持续剧烈运动à是恒温动物。然后呢?把恐龙带进去。哪个地方是有可能反驳的呢?听力部分一定是要打碎这个逻辑链。
分论点三的逻辑是：有哈弗森管à可以保护血管和神经à可以快速生长à恒温动物。而恐龙恰好有恒温动物。反驳的时候一定也是打碎逻辑链啦。
这种科学类的题目，很多都是建立在推测的基础上的，所以推理论证就是最常用的方式啦。因为，反驳的时候也一定用打碎逻辑链的方式。
听力材料：
Many scientists have problems with thearguments you read in the passage. They don’t think those arguments prove thatdinosaurs were endotherms.
很多科学家对你们刚刚听到的文章持有不同意见。他么认为这些理由不能支持恐龙是恒温动物。
Take the polar dinosaur argument. Whendinosaurs lived, even the Polar Regions, where dinosaur fossils have beenfound, were much warmer than today, warm enough during part of the year for animalsthat were not endotherms to live. And during the months when the Polar Regionswere cold, the so-called polar dinosaurs could have migrated to warmer areas orhibernated like many modern reptiles do. So the presence of dinosaur fossils inPolar Regions doesn’t prove the dinosaurs were endotherms.
先说一下极地恐龙的观点。当恐龙存在的时候，极地，也就是这些发现化石的地方比现在要暖和很多。而且当极地很冷的几个月里，这些极地恐龙会迁徙到暖和的地方或者像现在爬行动物一样选择冬眠。所以，在极地发现恐龙化石不能证明恐龙是恒温动物。
Well, what about the fact those dinosaurshave their legs placed under their bodies, not out to the side like crocodiles.That doesn’t necessarily mean dinosaurs were high-energy endotherms built forrunning. There is another explanation for having legs under the body. This bodystructure supports more weight, so with the legs under their bodies, dinosaurscan grow to a very large size.
Being large had advantages for dinosaurs,so we don’t need the idea of endothermy and running to explain why dinosaursevolved to have their legs under their bodies.
那么，恐龙的腿在身体下方而不是两侧是怎么回事呢?这个是不足以证明恐龙是可以进行奔跑类剧烈运动的恒温动物。腿生长在身体下部对于恐龙是别有的意义的。这样的结构可以支撑更多的重量。所以腿长在身体下部可以让恐龙长到非常大。对于恐龙来说，巨大的重量是非常有意义的，所以没有比用要用恒温动物和奔跑来解释为什么恐龙进化出这样的身体结构的。Ok, so how about bone structure? Many dinosaur bones do haveHaversian canals, and that is true.
The dinosaur bones also have growth rings.Growth rings are thickening of the bone that indicates periods of time when thedinosaurs weren’t rapidly growing. These growth rings are evidence that dinosaursstopped growing or grew more slowly during cooler periods. This pattern ofperiodic growth, you know, rapid growth followed by no growth or slow growth,and then rapid growth again, is characteristic of animals that are notendotherms. Animals that maintain a constant body temperature year-round astrue endotherms do grow rapidly even when the environment becomes cool.
恩，那么骨结构呢?很多恐龙确实有哈弗森管，这是事实不能否认。但是与此同时，恐龙还有生长环。生长环上比较厚的环节说明当时恐龙生长的缓慢。因此，生长环证明了恐龙在冷的时候生长缓慢甚至停止生长。这是一种周期性生长：一段时间不生长或者生长缓慢，然后接着快速生长。拥有这样生长方式的动物不是恒温动物。真正的恒温动物可以一年四季保持恒定的体温，因此可以在天气很冷的情况下快速生长。
托福综合写作听力笔记内容：
Main point：don’t
Sub point one: warmer, migrated,hibernated
Sub point two: doesn’t necessarily, forrunning, more weight, advantages
Sub point three: Haversian canals, growthring, slowly or stop V.S. rapid, periodic
这些词都听到了吗，都记下来了吗?如果都听到了，把他们带回到之前阅读部分总结的逻辑链，就可以告诉ETS是如何反驳的了，这样就能完成ETS要求的要体现阅读和听力部分的关系了。
托福综合写作范文(仅供参考)：
下面这篇作文是针对TPO第四套的综合写作(关于恐龙是否是恒温动物)写的，虽然有一些小错误，但ETS评分为满分。
Sample Response
The professor actually contradicts thestatements made in the passage. She is of the view that dinosaurs are notendotherms i.e. they were not able to keep their body temperature at a constantrate. The professor contradicts the issue of dinosaurs being endothers based onthe availability of fossils being available in thwe polar regions, she say thatthe polar regions in those days were not as cold as they are today i.e at leastwarm enough for dinosaurs to live. During harsh winters she says that there isa possibility of the dinosaurs actually migrating to warmer regions. The issueof leg position and movement being used as a reason to classify the dinosaursas endotherms does not please the professor either. She says that dinosaurs hadlegs under their bodies to support their huge bodies i.e the legs under thebody of the dinosaur were actually to support the huge weight of the dinosaurand not to provide it with a body structure like endotherms(which is actuallysuited for running).
The professor acknowledges the presence ofhaversian canals but also points out that that the fossils show the presence ofgrowth rings. These rings occur due to the thickening of the bone. Thethickening indicates that the dinosaurs were’nt actually growing continuouslybut were experiencing periods of rapid growth and periods of no growth insuccesion. This pattern. she says is characteristic of non-endothermicaanimals.
Thus it can be inferred that the professorchallenges the passage by giving reasons as to why she thinks that the dinosauris not an endotherm.
Description of Response:
Despite initial appearances, this responselargely succeeds in clearly and accurately presenting how the lecture points takeissue with the points in the reading passage that dinosaurs were endotherms.The first point regarding dinosaurs in polar regions could be a bit clearer.Otherwise, the response mainly suffers from typographical errors, but these arenot regarded as major problems; it is obvious that the writer has good controlof structure and vocabulary and the ability to use these to convey in anorganized and logical manner what has been understood and asked.