Cambridge IELTS 21 · Academic · Test 2 · Passage 1
Do Animals Dream? — IELTS Reading Answers
All 13 answers for Do Animals Dream?, Cambridge IELTS 21 Academic Reading Test 2 Passage 1, with evidence and explanations.
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Do Animals Dream? answer key at a glance
Questions 1–13. Tap an answer to see the evidence.
What this passage tests
The passage surveys sleep and dream research across species, from rats and pigeons to octopuses and cetaceans. Questions 1-5 complete a table of findings by species. Questions 6-13 are True/False/Not Given and turn on small wording differences such as 'may' versus 'does'.
Questions 1–5: Table Completion
Strategy: Work row by row. The row label tells you where to look; the column heading tells you what kind of word you need.
“For example, researchers compared the brain patterns of rats running through a maze when awake with their brain patterns during REM sleep. They found the patterns were very similar and concluded that the sleeping rats were dreaming about going through the maze”
Researchers compared rat brain patterns during a maze task and during REM sleep.
“Intriguingly, REM sleep activity was high in brain regions involved in processing visual information, especially images related to physical activities such as flying, which suggests that this may possibly be what the pigeons were dreaming about”
REM activity was high in brain regions 'processing visual information'.
“These include whales and dolphins, which do not shut down their entire brain when they sleep, but only half of it, keeping the rest awake”
Whales and dolphins shut down 'only half' of the brain when they sleep.
“It's thought that they don't experience REM sleep because during REM sleep animals are more vulnerable to extremes of temperature”
During REM sleep animals are 'more vulnerable to extremes of temperature'.
“They also show no sign of REM sleep, suggesting that they may only experience non-REM dreams, which are less vivid”
Non-REM dreams are 'less vivid', which completes the final cell of the table.
Questions 6–13: True / False / Not Given
Strategy: Judge the whole statement against the text. FALSE contradicts the passage; NOT GIVEN means the passage never addresses that specific claim.
Dreaming about past experiences helps us to create lasting memories of them.
“It is believed that when events are replayed in dreams, this helps to integrate memories into longer-term storage”
TRUE: replaying events in dreams 'helps to integrate memories into longer-term storage'.
It is now possible to tell what type of dream a dog is having.
“We are quick to interpret the twitching limbs and quiet barks of sleeping dogs, but the truth is that we don't know if there is an internal experience of chasing rabbits that comes along with that”
FALSE: we 'don't know if there is an internal experience' behind a dog's twitching limbs.
David Scheel's documentary was influential on other research into the sleeping patterns of octopuses.
“In 2019, while making a documentary, David Scheel of Alaska Pacific University in the USA housed an octopus named Heidi in a tank in his living room”
NOT GIVEN: the documentary is mentioned, but its influence on other research is not.
While it was asleep, the octopus called Costello reacted as if it was hunting.
“Costello, as the octopus was called, thrashed around, extended his mantle as if trying to make himself look bigger, and squirted ink as though he were being attacked by a predator”
FALSE: Costello thrashed, extended his mantle and squirted ink as if attacked, not as if hunting.
Scheel believes more research into octopuses' dreams should be carried out.
“The nightmare study is intriguing, says Scheel, but is only based on one animal. He argues that as well as outward behaviour, brain imaging is needed to show that the octopuses are replaying sequences of activities from their waking lives in dreams”
TRUE: Scheel argues brain imaging is needed, so further research should be carried out.
We may soon be able to share the dreams of other human beings.
“The trouble is that we will never be able to experience any animal's dreams. That goes for other humans' dreams too”
FALSE: the passage says 'we will never be able to experience any animal's dreams', including other humans'.
Hearing may be an important part of the dreams of some animals.
“For example, vision is the dominant sense for many humans, and so our dreams are heavily visual too. Dogs primarily navigate the world using smell while spiders rely much more on vibrations”
NOT GIVEN: the text notes dogs rely on smell and spiders on vibrations, but never says hearing matters in their dreams.
Interest in the reasons why humans dream has increased greatly in recent times.
“And if this is the case, it is possible that better understanding of these purposes might shed light on the true purpose of our own dreams”
NOT GIVEN: the passage says animal-dream research might reveal the purpose of dreams, not that public interest has grown.
Learn the question types in this passage
Traps in this passage
- The table is organised by species. Read the row label first, because the same detail (REM sleep) appears for several animals with different findings.
- Questions 9 and 10 look contradictory but are not: the octopus behaved as if attacked, and Scheel still wants brain imaging.
- Questions 12 and 13 are NOT GIVEN because the passage raises a possibility without making the claim in the statement.
Frequently asked questions
Where does the Do Animals Dream? passage come from?
It is Passage 1 of Cambridge IELTS 21 Academic Reading Test 2, and it covers Questions 1–13.
What question types appear in Do Animals Dream??
The passage is tested with Table Completion, True / False / Not Given. Each type is explained on this page, alongside the answers.
Are these reading answers reliable?
Every answer is paired with the sentence that proves it, so you can check each one against the passage yourself. Use the page after a timed attempt, not instead of one.
Cambridge IELTS is published by Cambridge University Press & Assessment. Band9Prep is not affiliated with Cambridge. This page is an independent study aid: it gives the answer key, the passage evidence and an explanation so you can review an attempt you have already made.