Read the following passage.
A. The yearly journey of the ruby-throated hummingbird begins in winter. Most of these birds spend the winter between southern Mexico and northern Panama, and they start moving north as early as January. By the end of February many have reached the northern coast of the Yucatan. There they feed heavily, and a bird can almost double its weight, from about 3.25 grams to over 6 grams. Some then fly about 800 kilometres across the Gulf of Mexico, while others travel around it along the Texas coast. A bird that makes the crossing may weigh only 2.5 grams when it lands.
B. The birds arrive at their breeding grounds in Canada during the last two weeks of May. Each male sets up a territory with several sources of food and chases intruders away. Hummingbirds eat small insects and drink nectar, and they prefer tube-shaped flowers such as bee balm and columbines. As a bird moves from flower to flower, it carries pollen to other plants of the same species. After mating, the male takes no part in raising the young. The female builds the nest on her own and lays two white eggs, which hatch after 11 to 14 days.
C. The trip south begins in the second half of August and continues into the first week of September. Males leave first, followed by females and juveniles, and young birds make their first migration alone, without a parent. Before they go, hummingbirds feed intensely, a feeding frenzy that scientists call hyperphagia. The fat they build up yields more than twice as much energy per gram as carbohydrates or protein, and scientists have calculated that it can fuel nonstop flight of nearly 600 miles. Bird banding has shown that hummingbirds return to the very same place the following spring.
D. Weather is a serious danger. Storms and untimely frost can kill hummingbirds, and the autumn flight comes during peak hurricane season, when strong headwinds over the Gulf can exhaust weaker birds. On cold nights a hummingbird may enter a sleep-like state called torpor, in which its heart rate falls from about 500 beats a minute to fewer than 50. Feeders bring risks of their own, because birds may attack their reflections in nearby windows and injure themselves, so feeders should hang 5 to 10 metres from glass. In 2024, Environment and Climate Change Canada and Birds Canada estimated that about 6.1 million live in Canada, but numbers have been falling since a peak around 2005.
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.
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Correct Answer: B
Why this is correct: Look at Paragraph B. After mating, the male takes no part in raising the young. So the female does this work alone.
Passage Reference: After mating, the male takes no part in raising the young.
Tips: Paragraph C also mentions young birds and parents. Look for the paragraph about the nest.
Why the other options are wrong:
- A: Paragraph A follows the birds north from their winter home. It does not talk about raising young.
- C: Paragraph C says young birds fly south without a parent. That is about the fall trip, not about who cares for chicks in the nest.
- D: Paragraph D is about weather, feeders and bird numbers. Parents and chicks are not discussed.
- E: The male's role after mating is described in Paragraph B. He takes no part in raising the young.
Correct Answer: D
Passage Reference: Feeders bring risks of their own, because birds may attack their reflections in nearby windows and injure themselves, so feeders should hang 5 to 10 metres from glass.
Why this is correct: The clue is in Paragraph D. Birds may attack their reflections in nearby windows. That is why feeders should hang 5 to 10 metres from glass.
Tips: Look at what can happen to birds at a feeder near a house. Check whether they get hurt by the glass.
Why the other options are wrong:
- A: Paragraph A describes how the birds gain weight before a long flight. Feeders and windows are not in it.
- B: Paragraph B tells you that males chase intruders away. It does not mention windows or glass.
- C: Paragraph C is about the trip south and the fat the birds store. It says nothing about feeders.
- E: Paragraph D explains this danger. Birds may attack their own reflections in windows near feeders.
Correct Answer: E
Passage Reference: Some then fly about 800 kilometres across the Gulf of Mexico, while others travel around it along the Texas coast.
Why this is correct: Paragraph A tells you some birds fly about 800 kilometres across the Gulf of Mexico. It never says what time of day they fly.
Tips: Paragraph D mentions nights, but not for the crossing. Check if any paragraph says when the birds cross.
Why the other options are wrong:
- A: Paragraph A gives the distance across the Gulf and the birds' weight. It does not say whether they fly by day or by night.
- B: Paragraph B covers arrival in Canada and nesting. The Gulf crossing is not part of it.
- C: Paragraph C tells you when the fall trip starts. It gives no time of day for any flight.
- D: Paragraph D mentions headwinds over the Gulf and cold nights. It does not say the crossing happens at night.
Correct Answer: D
Passage Reference: In 2024, Environment and Climate Change Canada and Birds Canada estimated that about 6.1 million live in Canada, but numbers have been falling since a peak around 2005.
Why this is correct: Look at Paragraph D. It says numbers have been falling since a peak around 2005. The estimate is from 2024, so the drop has lasted about twenty years.
Tips: Paragraph A has numbers as well. Make sure the number you choose counts birds.
Why the other options are wrong:
- A: Paragraph A gives numbers too, but they are weights in grams. It says nothing about how many birds there are.
- B: Paragraph B tells you when the birds arrive in Canada. It does not give a population figure.
- C: Paragraph C describes the fall trip and fat storage. The size of the population is not mentioned.
- E: The fall in numbers since about 2005 is reported in Paragraph D, with the 2024 estimate.
Correct Answer: A
Passage Reference: There they feed heavily, and a bird can almost double its weight, from about 3.25 grams to over 6 grams.
Why this is correct: The clue is in Paragraph A. Before the crossing, a bird can almost double its weight. It grows from about 3.25 grams to over 6 grams.
Tips: Paragraph C also describes heavy feeding. Only one paragraph gives weights in grams.
Why the other options are wrong:
- B: Paragraph B lists what the birds eat in Canada. It does not say how much weight they gain.
- C: Paragraph C also talks about eating a lot before a trip. But it gives no weight figures at all.
- D: Paragraph D talks about weaker birds in strong winds. It does not say how heavy a bird becomes.
- E: Paragraph A gives this fact. A bird can almost double its weight before crossing the Gulf.
Correct Answer: E
Passage Reference: Males leave first, followed by females and juveniles, and young birds make their first migration alone, without a parent.
Why this is correct: Look at Paragraph C. It says young birds make their first migration alone, without a parent. It never compares their speed with the speed of adult birds.
Tips: Be careful here. Paragraph C mentions young birds, but check whether it gives any speed.
Why the other options are wrong:
- A: Paragraph A describes the trip north in winter and spring. It does not compare young and adult birds.
- B: Paragraph B covers nesting and eggs. The speed of young birds is not given.
- C: Paragraph C does talk about young birds flying south. But it only says they go alone, not how fast they fly.
- D: Paragraph D mentions weaker birds in strong headwinds. It never says young birds are slower.
Correct Answer: D
Passage Reference: On cold nights a hummingbird may enter a sleep-like state called torpor, in which its heart rate falls from about 500 beats a minute to fewer than 50.
Why this is correct: On cold nights, paragraph D explains, a hummingbird may enter torpor. Its heart rate falls from about 500 beats a minute to fewer than 50.
Tips: Find what happens to a bird's heartbeat on cold nights. Compare the lower rate with the normal one. Is it a small part of it?
Why the other options are wrong:
- A: Paragraph A describes the journey north and weight gain. It does not mention the heart or cold nights.
- B: Paragraph B covers territory, food and nesting. Nothing in it is about heart rate.
- C: Paragraph C explains how fat gives energy for the trip. It does not describe what happens on cold nights.
- E: Paragraph D explains torpor. On cold nights the heart rate drops from about 500 to under 50 beats.
Correct Answer: C
Passage Reference: The fat they build up yields more than twice as much energy per gram as carbohydrates or protein, and scientists have calculated that it can fuel nonstop flight of nearly 600 miles.
Why this is correct: Paragraph C tells you this. The fat the birds build up yields more than twice as much energy per gram as carbohydrates or protein. Over double means more than twice.
Tips: Paragraph A also uses the idea of 'double'. Ask whether it is about weight or energy.
Why the other options are wrong:
- A: Paragraph A tells you a bird almost doubles its weight. That is about weight, not about how much energy each gram gives.
- B: Paragraph B describes nectar and insects as food. It does not compare fat with protein.
- D: Paragraph D is about weather, feeders and numbers. Energy per gram is not mentioned.
- E: The energy in fat compared with protein is given in Paragraph C.
Correct Answer: B
Passage Reference: Hummingbirds eat small insects and drink nectar, and they prefer tube-shaped flowers such as bee balm and columbines.
Why this is correct: Look at Paragraph B. Hummingbirds prefer tube-shaped flowers such as bee balm and columbines. A narrow pipe is the same shape as a tube.
Tips: Ask which flowers these birds like best. Then check whether their form matches a narrow pipe.
Why the other options are wrong:
- A: Paragraph A says the birds feed heavily on the Yucatan coast before the crossing. It does not say which flowers they like.
- C: Paragraph C says the birds feed intensely before the fall trip. It does not say which flowers they like.
- D: Paragraph D talks about feeders near windows. It gives no flower shapes.
- E: Paragraph B names the flowers the birds prefer. They are tube-shaped, like bee balm.
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