Listen to a lecture in a zoology class.
P: OK, calm down, please… it’s time to get started… You can continue your chitchat after class. Our topic for today is hibernation.
When it begins getting cold in the north as winter approaches, uh, different types of animals deal with the approach of the cold weather in different ways. Some animals move south to warmer weather, some animals increase their activity to stay warm, and other animals hibernate during the cold weather. So today, we’ll be discussing this third category of animals, the animals like
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groundhogs and bears that go into a state of unconsciousness or semi-consciousness during the cold winter months.
The first animal we’ll look at is the groundhog. The groundhog is one of the best-known hibernators. It goes into its burrow 4 or 5 feet underground sometime in the fall, and, uh, it doesn’t come out until spring. A groundhog stays in its underground burrow for the entire winter, without coming out. Now because the groundhog hibernates so completely, it’s the groundhog that has achieved prominence in our folklore as the animal that’s responsible for determining whether or not winter’s over and it’s safe to come out of hibernation.
You see, according to folklore, the groundhog will come out of the burrow where it’s hibernating on Groundhog Day in February. If winter’s over, the groundhog will remain out of its burrow, but if winter’s going to last for a while longer, the groundhog will scurry back into its burrow… Yes, Amanda, do you have a question?
A: Yes, I do. Does the groundhog have a good record, you know, about predicting whether winter’s over?
P: Uh, no, not really. It’s just a folktale, and the groundhog isn’t… um… batting much more than fifty-fifty. Now, back to the discussion of hibernation, with a little more emphasis on its scientific nature.
We’ve discussed the groundhog, which hibernates throughout the cold weather. Other animals that hibernate in a similar fashion are bats and squirrels. Now, we’ll look at the bear, which hibernates in a different manner.
You see, bears don’t hibernate as completely as groundhogs, bats or squirrels. In the southern half of the United States, bears don’t hibernate at all because the weather doesn’t get cold enough for them to hibernate. In the northern half of the United States, bears may not stay in hibernation for the entire wither. They may come out of their hibernation during the winter and wander about before returning to hibernation… Yes, Tom, what’s your question?
T: Well, professor, I’m not… uh… exactly sure what… um… hibernation is. I mean … how is hibernation different from sleep?
P: Ah, … that’s a good question, Tom, one that I’m a little late in clarifying. Hibernation is different from sleep, and these differences between sleep and hibernation are seen in body temperature and heart rate. You see, the main characteristics of hibernation, which are very different from sleep, are that body temperature and heart rate decrease significantly. When an animal comes out of hibernation, the heart rate and body temperature increase to the levels normal during waking hours.
During the period when a large animal, uh… such as a bear, is coming out of hibernation, the animal’s entire body does not warm at once. The area around the heart warms up first. As the heart warms up, it begins beating at its normal rate, and it's then able to pump blood around the rest of the body.
These are the main points that we need to cover about hibernation. Now, we’ll take a short break before moving on to the next subject.
Listen again to part of the lecture. Then answer the question.
(A)The students are late to class.
(B)The students are quite calm.
(C)The students must stay after class.
(D)The students are too noisy.
What is the topic of the talk?
(A)Why the groundhog hibernates
(B)Which folktales relate to hibernation
(C)How various animals hibernate
(D)Where animals hibernate
What is NOT mentioned by the professor as a way that various types of animals prepare for the cold weather?
(A)Some build warmer dens or nests.
(B)Some head to southern climates.
(C)Some increase their activity.
(D)Some hibernate, at least partially.
Listen again to part of the lecture. Then answer the question.
(A)He believes in it.
(B)He’s shocked by it.
(C)He’s enthusiastic about it.
(D)He’s unimpressed by it.
Which is NOT a good hibernator?
(A)A groundhog
(B)A squirrel
(C)A bat
(D)A bear
Listen again to part of the lecture. Then answer the question.
(A)To indicate that Tom should have asked that question earlier
(B)To show that hibernation should have been defined earlier
(C)To state that the lecture should have been started earlier
(D)To indicate that the question had already been answered
What happens to body temperature and heart rate during hibernation?
Click on 2 answers
(A)Body temperature increase
(B)Body temperature decrease
(C)Heart rate increase
(D)Heart rate decrease
What part of the bear most likely warms up first from hibernation?
(A)The head
(B)The paws
(C)The chest
(D)The tail