[ 2204听力 ]

Posted 2023-02-07 we1less

[ 第一次课 生物学 ]

Listen to part of a lecture in a Zoology class
(female professor) OK, last time we started our discussion on horns and antlers, and we mostly focused on antlers. Um, would someone remind us of the differences between horns and antlers?

        antlers  n. 鹿角

        提问：would

        对比：differences

        笔记示范 ：an

(male student) Well, antlers are made of bone, and they have to be regrown every year, that is, they fall off in the winter and start growing again in the spring. Horns are permanent. They don’t fall off, and they are not made of bone. They are actually made of the same stuff that fingernails are made of.

        笔记示范 ：

(professor) Good, um, what else? OK, Sharon?

(female student) Antlers are found on members of the deer family, like deer, moose, elk and so on, and it’s usually just the males that have them. But many different kinds of animals have horns and they can usually be found on both males and females, you know, depending on species.

        笔记示范 ：

(professor) Um, and what are they used for?

(female student) Well, both horns and antlers can be used for competing for mates, defending territory, and even protection from predators.

        compete  vi. 竞争;对抗;参加比赛(或竞赛)

(professor) OK, good, and, um, now, today we’re gonna focus on horns, and horns found on creatures other than mammals.

(male student) Do you mean, like, birds, like, great horn owls?

        owl  n. 猫头鹰;

        great horn owl  大角鸮

(female student) Excuse me, but aren’t the horns on a horned owl really just tufts of feathers that stick up and only look like horns?

        horned owl  雕鸮

        tuft  n. 簇;(在底部丛生或聚集的)一绺毛发，一丛草

        stick up  撅;竖起

(professor) Yes, that’s right. Uh, a few birds have the word horn in their names, but, they don’t really have horns.

But I was thinking about the examples from our textbook.

(male student) Chameleons and, uh, what was the other one?

(female student) Dung beetles

(professor) Right, the dung beetle in our book is one of those species where just the male has horns. Do you remember what they are used for?

(male student) Male dung beetles use their horns to keep away other dung beetles. Uh, they live in tunnels, so their horns are used for keeping competitors away from a female mate. They use their horns to block a rival’s passage through the tunnel.

(professor) Right, yes, to keep competitors away. 

And what about those chameleons? Hmm?

(female student) The Jackson’s chameleon? It has a different reason for having horns.

(professor) OK, go on.

(female student) Well, it’s got those three horns sticking out of its face, and they use them partly to keep competitors away from their mates like dung beetles, but also just to defend their territory.

(professor) That’s right. Yes, chameleons in general, including the Jackson’s chameleon, are not well-known for their ferocity, and they are just as likely to try to outstare a rival chameleon as to try to push it around with its horns. But you’re right, uh, some animals, even the occasional chameleon, use their horns to protect their territory.

        in general  一般（或总的）说来;

        ferocity  n. 残暴;凶猛;凶恶;猛烈

(female student) What about defending themselves from predators?

(professor) Good, I’m glad you mention that one, because that reminds me of a recent study on the horned lizard, and how it uses its horns not just to defend itself against attacking predators, but also to frighten predators into not attacking in the first place.

Um, in the study, the biologists compared the length of the horns of living horned lizards with those of dead horned lizards, lizards that had been killed by their main predator, a bird called a shrike which is like a hawk. The study found that the horns on the live lizards were ten percent longer than the horns of lizards that were killed. The study also concluded that any lizards with horns that were at least, uh, if I’m not mistaken, eighty percent as long as its head, seem to be safe from the birds. So, for the horned lizard, it seems that the longer the horn, the better their chances.

实验：in the study

        ① 实验目的  [ 分层中心 / 文章主旨 ]

        ② 实验对象

        ③ 实验步骤  [ 脑补 ]

        ④ 结果 + 评价 The study found

OK, now, last time we mentioned the cost of antlers, about how in order for deer to grow antlers, their bodies have to use minerals from their bones. And so, one cost of the antlers to the deer is the temporary weakening of their bones while the antlers are growing. It’s actually similar to cost of horns on dung beetles. So, what do you remember about that? John?

(male student) Well, um, for insects, like the dung beetle, the cost of horn is, well, I’d say it’s a trade-off.

(professor) How so?

(male student) Well, say a horn grows on a beetle’s head. The beetle usually ends up with smaller organs near that horn, like the antennae, or the eyes. And they end up smaller, because that one horn use nutrients those organs could have used to grow to their full size.

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1. What is the lecture mainly about?

        答案：概括性的、总结性的、文章大部分说的；kw：horn

A) Differences between mammal and insect horns

B) The uses of horns by various animal species

C) Identifying different animal species by their horns

D) Various reasons most mammals and insects lack horns 

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2. According to the lecture, in what way are antlers different from horns? [choose two answers]

        [ 提问 + 对比 ] bone；regrow；deer；male

A) Their permanence

        permanence  n. 永久性;持久性;永久

B) Their purposes 

        purpose  n. 意图;目的;用途;

C) The material they are made of

D) Their evolution

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3. What purpose do dung beetle horns primarily serve?

        [ 提问 ] keeping competitors away

A) To dig tunnels for living space

B) To help in finding food

C) To attract female dung beetles

D) To defend against rival males

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4. What did the study on horned lizards conclude?

        Predators

        [ 因果 ] the longer the horn, the better their chances.

A) Lizards with longer horns were more likely to attract males.

B) Lizards with longer horns were less likely to be attacked by predators.

C) The eye size of the horned lizards was affected by the size of their horns.

D) Predators were more attracted to female than male horned lizards.

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5. In the lecture, what is the reduced size of dung beetle’s antennae and eyes compared to?

        [ 对比 ]

        [ 因果 ] deer - bone 

A) The number of horns on a chameleon’s face

B) The length of the horned lizard’s horns

C) The weakening of the deer’s bones during the growth of antlers

D) The size of the deer’s antlers during winter

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6. What does the student imply when she says this:  

        ① 句意

        ② 逻辑

        互动性的对话

        [ 强调 / 否定 ]

        but / wait / excuse me / well

        [ 赞同 ]

        p：观点 A

        s：so ... + B

A) She is not sure how birds should be classified.   跟中心不相关

B) She did not understand what the man said.

C) The man’s statement is incomplete.

        statement  n. 陈述;声明;报表;说法;报告;

        incomplete  adj. 不完整的;不完全的;不完善的

D) There is a problem with the man’s example.