NARRATOR:
You will hear two students discussing a presentation about woolly mammoths with their tutor.
NARRATOR:
First, you have some time to look at questions 21 to 24.
NARRATOR:
Now listen carefully and answer questions 21 to 24.
TUTOR:
Right, Rosie and Martin, let's see how far you've got with your presentation on woolly mammoths.
ROSIE:
Sure, we've brought along a brief plan.
TUTOR:
Your main focus is a research study in North America, is that right?
MARTIN:
Yes, though, we thought the opening should give some background first.
MARTIN:
We'll explain that woolly mammoths were relatives of today's elephants, and lived during the last ice age, many thousands of years ago.
ROSIE:
We considered starting with a short extract from a cartoon about mammoths, but it might seem rather childish.
ROSIE:
A diagram could work better.
ROSIE:
Perhaps a timeline with pictures to show the period when they lived.
MARTIN:
What about a sketch of a herd crossing the ice?
MARTIN:
Your timeline idea would introduce the topic more effectively.
TUTOR:
After that, you cover the mammoth tooth discovered on St. Paul's Island in Alaska, and explain why the find mattered.
ROSIE:
Russell Graham found the tooth beneath a rock in a cave.
ROSIE:
It was exceptionally well preserved.
ROSIE:
It looked almost as though it had only recently been taken from the animal's jaw.
ROSIE:
Tests showed that it was about 6,500 years old.
TUTOR:
And why was that result important?
ROSIE:
Because mammoth remains previously discovered on the North American mainland dated from much earlier.
ROSIE:
Finding such a comparatively recent tooth was extraordinary.
MARTIN:
Then we'll use an animated graphic to reconstruct the region in prehistoric times.
MARTIN:
At first, St. Paul's was joined to the mainland, so mammoths, bears, and other animals could move freely across the whole area.
ROSIE:
As the climate became warmer, sea levels rose and the land connection disappeared.
ROSIE:
The mammoths were left cut off on the new island, with no route back to the mainland.
MARTIN:
They actually continued living there for several thousand years after mammoths had vanished from the mainland.
TUTOR:
Do researchers know what caused the mainland population to disappear?
ROSIE:
There isn't a definite explanation.
MARTIN:
Next we'll describe how Graham's team worked out when the island mammoths became extinct.
MARTIN:
They placed it at 5,600 years ago, which is unusually precise for an event in prehistory.
MARTIN:
Their evidence came from material collected in the mud at the bottom of an island lake.
MARTIN:
By examining the layers, they could identify plant fragments, volcanic ash, and even mammoth DNA deposited over time.
MARTIN:
The method itself is routine, although analyzing the samples took almost two years.
NARRATOR:
Before you hear the rest of the discussion, you have some time to look at questions 25 to 30.
NARRATOR:
Now listen and answer questions 25 to 30.
TUTOR:
Why don't you now review the main sections of the presentation and decide what still has to be done for each one?
MARTIN:
For the introduction, we're planning to use that visual.
MARTIN:
So once we've made it, I suppose the section is finished.
ROSIE:
I'm not convinced.
ROSIE:
We should prepare detailed notes covering every point we want to mention rather than trusting ourselves to remember it all.
ROSIE:
The opening matters too much to improvise.
ROSIE:
The discovery of the tooth is probably the most striking part, but our only source so far is that article we found online, and it doesn't give us much detail.
ROSIE:
Perhaps we could contact the scientist who directed the research and ask for some additional information.
MARTIN:
That sounds useful.
MARTIN:
What should we do with the section about the researcher's original questions?
MARTIN:
We've gathered plenty of material, but we need a lively way to present it.
ROSIE:
We could invite the audience to propose questions of their own.
ROSIE:
Then check how many our presentation can answer.
ROSIE:
It shouldn't take very long.
TUTOR:
Yes, that would make the session more varied.
MARTIN:
Then there's the later work on the island, particularly the analysis of the lake mud.
MARTIN:
We may have included too much.
MARTIN:
Do you think some of it should be removed?
ROSIE:
I'd keep the information, but the way it's arranged is confusing at the moment.
MARTIN:
In that case, we could put the research stages into chronological order.
ROSIE:
The section on the results and possible interpretations is nearly complete, although we ought to rehearse it and check that it stays within the allotted time.
MARTIN:
It will probably fit, but we should confirm that.
TUTOR:
For the final section on its significance today, you've collected some strong ideas.
TUTOR:
What's missing is your own interpretation, rather than another summary of other people's views.
MARTIN:
We'll work on that.
NARRATOR:
That is the end of part three.
NARRATOR:
You now have one minute to check your answers
