英语听力：2013-05-19 完美捕食 Perfect Predators —8

 Sauroposeidon towers over Deinonychus. In fact, its mammoth¹ size is its primary defense². But this giant begins life very small. 

 

For Deinonychus, Sauroposeiden would be a great meal, at least the juveniles³, because there would’ve been lots of them and because they would’ve been effectively defenseless. 

 

When Sauroposeidon reaches full size at around 25 years old, nothing can compete. But this Goliath starts out about the size of a house cat. When these eggs hatch, the young grow fast, but not fast enough. They won’t even reach a ton in weight for at least three years, giving the raptor Dinosaurs⁴ plenty of time to attack. 

 

There’s good evidence that Deinonychus killed animals that weighed 10 times as much as it. 

 

And 10 times Deinonychus’ weight in raw meat is a very big meal. 

 

They could probably feast for a while on, say, a three-year-old Sauroposeidon, an animal the size of a hippo.

 

Bringing down an animal 10 times your size takes more than just brains. It requires highly advanced senses. 

 

We can tell that it had a good sense of vision, good hearing, and a pretty good sense of smell.

 

In fact, like few carnivores of its day, Deinonychus has a sense of smell so acute, it can track prey⁵ in the dead of night. 

 

Inside the snout are two nasal passages. Like an air filter, sheets of sensory⁶ tissue are folded to maximize surface area. This tissue contains millions of chemoreceptors, nerves that capture odor molecules⁷. So Deinonychus can sniff⁸ out prey from miles away. 

 

The sense of smell in Deinonychus could alert…

 

1 mammoth   

n.长毛象；adj.长毛象似的，巨大的

参考例句：

• You can only undertake mammoth changes if the finances are there.资金到位的情况下方可进行重大变革。
• Building the new railroad will be a mammoth job.修建那条新铁路将是一项巨大工程。

2 defense   

n.防御，保卫；[pl.]防务工事；辩护，答辩

参考例句：

• The accused has the right to defense.被告人有权获得辩护。
• The war has impacted the area with military and defense workers.战争使那个地区挤满了军队和防御工程人员。

3 juveniles   

n.青少年( juvenile的名词复数 )；扮演少年角色的演员；未成年人

参考例句：

• Do you think that punishment for violent crimes should be the same for juveniles and adults? 你对暴力犯罪的惩罚对于青少年和成人应一样吗？ 来自生活英语口语25天快训
• Juveniles Should we not exactly in need of such strength and conviction? 少年的我们难道不正是需要这种力量和信念吗？ 来自互联网

4 dinosaurs   

n.恐龙( dinosaur的名词复数 )；守旧落伍的人，过时落后的东西

参考例句：

• The brontosaurus was one of the largest of all dinosaurs. 雷龙是所有恐龙中最大的一种。 来自《简明英汉词典》
• Dinosaurs have been extinct for millions of years. 恐龙绝种已有几百万年了。 来自《简明英汉词典》

5 prey   

n.被掠食者，牺牲者，掠食；v.捕食，掠夺，折磨

参考例句：

• Stronger animals prey on weaker ones.弱肉强食。
• The lion was hunting for its prey.狮子在寻找猎物。

6 sensory   

adj.知觉的，感觉的，知觉器官的

参考例句：

• Human powers of sensory discrimination are limited.人类感官分辨能力有限。
• The sensory system may undergo long-term adaptation in alien environments.感觉系统对陌生的环境可能经过长时期才能适应。

7 molecules   

分子( molecule的名词复数 )

参考例句：

• The structure of molecules can be seen under an electron microscope. 分子的结构可在电子显微镜下观察到。
• Inside the reactor the large molecules are cracked into smaller molecules. 在反应堆里，大分子裂变为小分子。

8 sniff   

vi.嗅…味道；抽鼻涕；对嗤之以鼻，蔑视

参考例句：

• The police used dogs to sniff out the criminals in their hiding - place.警察使用警犬查出了罪犯的藏身地点。
• When Munchie meets a dog on the beach, they sniff each other for a while.当麦奇在海滩上碰到另一条狗的时候，他们会彼此嗅一会儿。