Read the following passage.
A. The Canada lynx is a wild cat of the boreal forest, the northernmost forest in the Northern Hemisphere. Its large feet, covered in winter by thick, coarse hair, help it travel over snow. The lynx preys almost entirely on the snowshoe hare, so its fortunes depend closely on its prey. Hare numbers rise and fall in a cycle about 10 years long, and lynx numbers climb as hares increase and then crash. Scientists who studied the fur-trading records of the Hudson's Bay Company were able to trace these linked cycles over the past 200 years.
B. The snowshoe hare is one of the commonest forest mammals and is found only in North America. Its fur changes from grey-brown in summer to almost pure white in midwinter, a change triggered by the length of the day. At the peak of a cycle, hares can reach 500 to 600 per square kilometre, and in those years they may kill saplings and shrubs by stripping rings of bark. Peaks happen at roughly the same time across the hare's range, although they can differ by one to three years between regions. Declines are largely caused by predation, and lynx, red foxes, coyotes, mink, great horned owls and northern goshawks are among the common hunters of hares.
C. For the lynx, the cycle brings years of plenty and years of hunger. Snowshoe hares make up more than 75 per cent of its winter diet, and when they are abundant, a lynx may kill one every one or two days. When hares are scarce, each lynx needs a larger area to hunt. After a hare crash, about 40 per cent of the lynx population may starve. In the three to four years that follow, lynxes still breed, but the kittens die before winter. Lynxes that do not starve must move away, and during some past crashes they entered Edmonton, Calgary and Winnipeg.
D. Many questions remain open. Trapping during the low years of the cycle can seriously reduce or even wipe out local lynx populations, and some biologists have recommended closing trapping seasons entirely during those lows. Scientists also still poorly understand how lynxes use and share their home ranges. The effects of diseases such as rabies and distemper on lynx populations are also unknown. Logging, fire, habitat conversion and global warming are changing the forests, and scientists do not know how these changes will affect the 10-year cycle.
E. Not given in any of the above paragraphs.
Decide which paragraph, A to D, has the information given in each statement below. Select E if the information is not given in any of the paragraphs.
AI explanationShows the answer. Tap to open.
Correct Answer: B
Why this is correct: Look at Paragraph B. At the peak of a cycle, hares can reach 500 to 600 per square kilometre. A square kilometre is a thousand metres on each side. And 500 to 600 is hundreds of hares.
Passage Reference: At the peak of a cycle, hares can reach 500 to 600 per square kilometre, and in those years they may kill saplings and shrubs by stripping rings of bark.
Tips: Look for a number of hares in a piece of land, not a number of years.
Why the other options are wrong:
- A: In Paragraph A, hare numbers rise and fall in a cycle of about 10 years. No count of hares per area is given.
- C: Paragraph C mentions years when hares are abundant. It never says how many live in one piece of forest.
- D: Paragraph D is about trapping, disease and changing forests. It has no figures for hare numbers.
- E: The text gives this figure. The peak of 500 to 600 hares per square kilometre is in Paragraph B.
Correct Answer: D
Passage Reference: Scientists also still poorly understand how lynxes use and share their home ranges.
Why this is correct: Look near the end of Paragraph D. Scientists still poorly understand how lynxes use and share their home ranges. Sharing a home range is how the cats divide up space.
Tips: The statement describes a gap in research. Make sure the gap is about how the cats divide up space.
Why the other options are wrong:
- A: Paragraph A describes the lynx and its link to the hare. How lynxes use space is not discussed.
- B: Paragraph B mentions the hare's range across regions. It says nothing about lynxes sharing ground.
- C: Paragraph C tells you a lynx needs a larger hunting area when hares are scarce. That is stated as fact, not as an open question.
- E: The text does mention this. The poor understanding of home ranges is in Paragraph D.
Correct Answer: B
Passage Reference: Declines are largely caused by predation, and lynx, red foxes, coyotes, mink, great horned owls and northern goshawks are among the common hunters of hares.
Why this is correct: The clue is near the end of Paragraph B. Declines are largely caused by predation. Predation means animals hunting and eating other animals. The paragraph then lists the common hunters of hares.
Tips: Paragraph C also shows lynxes eating hares. Decide which paragraph explains why hare numbers drop.
Why the other options are wrong:
- A: Paragraph A tells you the lynx preys on the hare. It does not say what makes hare numbers fall.
- C: Paragraph C shows how often a lynx kills hares and what happens to lynxes after a crash. It does not say what causes the crash.
- D: Paragraph D talks about trapping lynxes and lynx diseases. It gives no cause for falling hare numbers.
- E: The text names this cause. Predation as the main reason for hare declines is in Paragraph B.
Correct Answer: E
Passage Reference: Peaks happen at roughly the same time across the hare's range, although they can differ by one to three years between regions.
Why this is correct: Be careful with Paragraph B. Peaks happen at roughly the same time across the hare's range. They can differ by one to three years between regions. But it never says which region peaks first, and east and west are not named.
Tips: Paragraph B gives a gap between regions. Check if it says which region is ahead.
Why the other options are wrong:
- A: Paragraph A gives the length of the cycle, about 10 years. It does not compare parts of the country.
- B: Paragraph B allows a gap of one to three years between regions. It names no region as earlier or later.
- C: Paragraph C names Edmonton, Calgary and Winnipeg as places lynxes entered. It does not say when hares peak there.
- D: Paragraph D lists open questions about trapping, disease and forests. East and west are never compared.
Correct Answer: C
Passage Reference: After a hare crash, about 40 per cent of the lynx population may starve.
Why this is correct: Look at Paragraph C. After a hare crash, about 40 per cent of the lynx population may starve. Forty per cent is a large share. Starving means dying from lack of food.
Tips: Paragraph A also mentions lynx numbers crashing. Find the paragraph that gives hunger as the cause.
Why the other options are wrong:
- A: In Paragraph A, lynx numbers crash after hares decline. It gives no share of lynxes lost to hunger.
- B: Paragraph B lists the lynx among the hunters of hares. It says nothing about lynxes dying.
- D: Paragraph D warns that trapping can reduce lynx numbers. Those losses come from people, not hunger.
- E: The text gives this share. The 40 per cent of lynxes that may starve is in Paragraph C.
Correct Answer: A
Passage Reference: Scientists who studied the fur-trading records of the Hudson's Bay Company were able to trace these linked cycles over the past 200 years.
Why this is correct: Check the last sentence of Paragraph A. Scientists studied the fur-trading records of the Hudson's Bay Company. From them, they traced the linked cycles over the past 200 years. Those records are business documents.
Tips: Two things must match here: the kind of documents and the number of years involved. Check both.
Why the other options are wrong:
- B: Paragraph B describes the hare cycle and its peaks. It does not mention records or how far back the pattern goes.
- C: Paragraph C tells of lynxes entering cities during past crashes. It does not use records to trace the cycle.
- D: Paragraph D lists what scientists still do not know. Old fur-trade records are not part of it.
- E: The text includes this. The fur-trading records and the 200 years are in Paragraph A.
Correct Answer: C
Passage Reference: In the three to four years that follow, lynxes still breed, but the kittens die before winter.
Why this is correct: Read Paragraph C. In the three to four years after a hare crash, lynxes still breed. But the kittens die before winter. Kittens are young lynxes, and winter is the cold season.
Tips: Focus on the young born after a collapse. Check what happens to them, and when.
Why the other options are wrong:
- A: Paragraph A tells you lynx numbers crash. It does not mention young lynxes or when they die.
- B: Paragraph B describes hares and their white winter fur. Lynx young are not discussed.
- D: Paragraph D names diseases and trapping as threats. Lynx kittens are not mentioned.
- E: You can read about the kittens that die before winter in Paragraph C.
Correct Answer: E
Passage Reference: Scientists who studied the fur-trading records of the Hudson's Bay Company were able to trace these linked cycles over the past 200 years.
Why this is correct: Paragraph A says scientists studied the fur-trading records of the Hudson's Bay Company to trace the cycles. It does not say who first noticed the pattern. Company workers are never mentioned.
Tips: Ask who noticed the pattern first. The text may name only the people who studied the records later.
Why the other options are wrong:
- A: The company's records are in Paragraph A, but the people there are scientists who studied them. Nobody is called the first to notice.
- B: Paragraph B describes the hare cycle. It names no one who discovered it.
- C: Paragraph C tells what happens to lynxes during the cycle. It does not say who spotted the cycle.
- D: Paragraph D mentions biologists and scientists only for questions that are still open.
Correct Answer: D
Passage Reference: Trapping during the low years of the cycle can seriously reduce or even wipe out local lynx populations, and some biologists have recommended closing trapping seasons entirely during those lows.
Why this is correct: Look at Paragraph D. Some biologists have recommended closing trapping seasons entirely during the low years. That means no trapping at all when lynx numbers are lowest.
Tips: You want advice from experts, not just a fact. Is the advice a full ban when cat numbers hit the bottom?
Why the other options are wrong:
- A: Paragraph A tells you lynx numbers crash. It does not suggest any limit on trapping them.
- B: Paragraph B lists animals that hunt hares. People trapping lynxes are not discussed.
- C: Paragraph C describes lynxes starving and moving away in low years. It gives no advice about trapping.
- E: The text gives this advice. Closing trapping seasons during the lows is in Paragraph D.
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