SECTION 3
READING PASSAGE 3
You should spend about 20 minutes on Questions 28-40 which
are based on Reading Passage 3 below.
Extinct: the Giant Deer
Toothed
cats, mastodons, giant sloths, woolly rhinos, and many other big, shaggy
mammals are widely thought to have died out around the end of the last ice age,
some 10,500 years ago.
A
The Irish elk is also known as
the giant deer (Megaloceros giganteus). Analysis of ancient bones and teeth by
scientists based in Britain and Russia show the huge herbivore survived until
about 5,000 B.C. – more than three millennia later than previously believed.
The research team says this suggests additional factors, besides climate change,
probably hastened the giant deer’s eventual extinction. The factors could
include hunting or habitat destruction by humans.
B
The Irish elk, so-called because
its well-preserved remains are often found in lake sediments under peat bogs in
Ireland, first appeared about 400,000 years ago in Europe and Central Asia.
Through a combination of radiocarbon dating of skeletal remains and the mapping
of locations where the remains were unearthed, the team shows the Irish elk was
widespread across Europe before the last “big freeze.” The deer’s range later contracted
to the Ural Mountains, in modern-day Russia, which separate Europe from Asia.
C
The giant deer made its last stand in
western Siberia, some 3,000 years after the ice sheets receded, said the
study’s co-author, Adrian Lister, professor of palaeobiology at University
College London, England. “The eastern foothills of the Urals became very
densely forested about 8,000 years ago, which could have pushed them on to the
plain,” he said. He added that pollen analysis indicates the region then became
very dry in response to further climatic change, leading to the loss of
important food plants. “In combination with human pressures, this could have
finally snuffed them out,” Lister said.
D
Hunting by humans has often been
put forward as a contributory cause of extinction of the Pleistocene megafauna.
The team, though, said their new date for the Irish elk’s extinction hints at
an additional human-made problem – habitat destruction. Lister said, “We
haven’t got just hunting 7,000 years ago – this was also about the time the
first Neolithic people settled in the region. They were farmers who would have
cleared the land.” The presence of humans may help explain why the Irish elk
was unable to tough out the latest of many climatic fluctuations – periods it
had survived in the past.
E
Meanwhile, Lister cast doubt on
another possible explanation for the deer’s demise – the male’s huge antlers.
Some scientists have suggested this exaggerated feature – the result of females
preferring stags with the largest antlers, possibly because they advertised a
male’s fitness – contributed to the mammal’s downfall. They say such antlers
would have been a serious inconvenience in the dense forests that spread northward
after the last ice age. But, Lister said, “That’s a hard argument to make
because the deer previously survived perfectly well through wooded
interglacials [warmer periods between ice ages].” Some research has suggested
that a lack of sufficient high-quality forage caused the extinction of the elk.
High amounts of calcium and phosphate compounds are required to form antlers,
and therefore large quantities of these minerals are required for the massive
structures of the Irish Elk. The males (and male deer in general) met this
requirement partly from their bones, replenishing them from food plants after
the antlers were grown or reclaiming the nutrients from discarded antlers (as
has been observed in extant deer). Thus, in the antler growth phase, Giant Deer
was suffering from a condition similar to osteoporosis. When the climate changed
at the end of the last glacial period, the vegetation in the animal’s habitat
also changed towards species that presumably could not deliver sufficient
amounts of the required minerals, at least in the western part of its range.
F
The extinction of megafauna
around the world was almost completed by the end of the last ice age. It is
believed that megafauna initially came into existence in response to glacial
conditions and became extinct with the onset of warmer climates. Tropical and
subtropical areas have experienced less radical climatic change. The most
dramatic of these changes was the transformation of a vast area of North Africa
into the world’s largest desert. Significantly, Africa escaped major faunal
extinction as did tropical and sub-tropical Asia. The human exodus from Africa
and our entrance into the Americas and Australia were also accompanied by
climate change. Australia’s climate changed from cold-dry to warm-dry. As a
result, surface water became scarce. Most inland lakes became completely dry or
dry in the warmer seasons. Most large, predominantly browsing animals lost
their habitat and retreated to a narrow band in eastern Australia, where there
were permanent water and better vegetation. Some animals may have survived
until about 7000 years ago. If people have been in Australia for up to 60 000
years, then megafauna must have co-existed with humans for at least 30 000
years. Regularly hunted modern kangaroos survived not only 10 000 years of
Aboriginal hunting, but also an onslaught of commercial shooters.
G
The group of scientists led by
A.J. Stuart focused on northern Eurasia, which he was taking as Europe, plus
Siberia, essentially, where they’ve got the best data that animals became
extinct in Europe during the Late Pleistocene. Some cold-adapted animals, go through
into the last part of the cold stage and then become extinct up there. So
you’ve actually got two phases of extinction. Now, neither of these coincide –
these are Neanderthals here being replaced by modern humans. There’s no obvious
coincidence between the arrival of humans or climatic change alone and these
extinctions. There’s a climatic change here, so there’s a double effect here.
Again, as animals come through to the last part of the cold stage, here there’s
a fundamental change in the climate, reorganization of vegetation, and the
combination of the climatic change and the presence of humans – of advanced
Paleolithic humans – causes this wave of extinction. There’s a profound
difference between the North American data and that of Europe, which summarize
that the extinctions in northern Eurasia, in Europe, are moderate and
staggered, and in North America severe and sudden. And these things relate to
the differences in the timing of human arrival. The extinction follows from
human predation, but only at times of fundamental changes in the environment.
Questions 28-32
Complete the following summary of
the paragraphs of Reading Passage.
Using NO MORE THAN THREE WORDS from the Reading Passage for each answer.
Write
your answers in boxes 28-32 on your
answer sheet.
Having been preserved well in
Europe and Central Asia, the remains of the Irish elk was initially found
approximately 28………………………. Around 29…………………………, they were driven to live
in the plain after being restricted to the Ural Mountains. Hunting was
considered as one of the important factors of Irish elk’s extinction, people
have not started hunting until 30……………………..
when Irish elk used to get through under a variety of climatic fluctuations.
The huge antlers may possibly
contribute to the reason why Irish elk extinct, which was highly controversial
as they live pleasantly over the span of 31……………………….
Generally, it is well-known that, at the last maximum ice age, mammals become
extinct about 32…………………….
Questions 33-35
Answer the questions below.
Choose NO MORE THAN THREE WORDS AND/OR A NUMBER
from the passage for each answer.
33
What kind of physical characteristics
eventually contributed to the extinction of Irish elk?
34
What kind of nutrient substance needed in
maintaining the huge size of Irish elk?
35
What geographical evidence suggested the
advent of human resulted in the extinction of Irish elk?
Questions 36-39
Choose the letter A-D and fill in boxes 36-39
A
Eurasia
B
Australia
C
Asia
D
Africa
36
the continents where humans imposed a little
impact on large mammals extinction
37
the continents where the climatic change was
mild and fauna remains
38
the continents where both humans and
climatic change are the causes
39
the continents where the climatic change
along caused a massive extinction
Question 40
Which statement is true according
to the Stuart team’s finding?
A
Neanderthals rather than modern humans
caused the extinction in Europe
B
Paleolithic humans in Europe along kill the
big animals such as Giant deer
C
climatic change was not solely responsible
for the megafauna extinction in Europe
D
moderate and staggered extinction was mainly
the result of fundamental climatic change
ANSWER
28. 400,000
years ago
29. 8000
years ago
30. 7000
years ago
31. wooded
interglacials
32. 10500
years ago
33. Male’s
huge antlers
34. minerals
35. habitat
destruction
36. B
37. D
38. A
39. C
40. C
PASSWORD: REALEXAM22
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