Cambridge IELTS 10 Academic Reading Test 4: answers explained

Explanation for each answer

Passage 1 · Q1–13 The megafires of California

1. Question 1

   Note completion

   Question

   movement: ______ more unpredictably

   Answer

   spread

   Location

   Passage 1, paragraph 1

   Sentence in the passage

   The wildfires themselves, experts say, are generally hotter, faster, and spread more erratically than in the past.

   Explanation

   The note states that wildfires move more 'unpredictably' compared to the past, and asks for a word to complete the phrase '__________ more unpredictably'. The third sentence of the first paragraph says wildfires "spread more erratically than in the past". 'Erratic' is a synonym for 'unpredictable'. The word 'spread' fits grammatically and matches the context, and is one word, adhering to the word limit.

2. Question 2

   Note completion

   Question

   size of fires: ______ greater on average than two decades ago

   Answer

   10/ ten times

   Location

   Passage 1, paragraph 2

   Sentence in the passage

   Megafires, also called ‘siege fires’, are the increasingly frequent blazes that burn 500,000 acres or more - 10 times the size of the average forest fire of 20 years ago.

   Explanation

   The note asks about the size of megafires compared to the past, stating they are '__________ greater on average than two decades ago'. The first sentence of the second paragraph defines 'Megafires' as blazes that "burn 500,000 acres or more – 10 times the size of the average forest fire of 20 years ago". This directly provides the numerical comparison: they are '10 times' greater. The answer is '10', which is a number and fits the 'ONE WORD AND/OR A NUMBER' limit.

3. Question 3

   Note completion

   Question

   rainfall: ______ average

   Answer

   below

   Location

   Passage 1, paragraph 3

   Sentence in the passage

   One explanation for the trend to more superhot fires is that the region, which usually has dry summers, has had significantly below normal precipitation in many recent years.

   Explanation

   The note asks about rainfall levels in relation to wildfires today, indicating it's '__________ average'. The first sentence of the third paragraph provides a reason for the trend to more superhot fires: the region "has had significantly below normal precipitation in many recent years". 'Precipitation' is a synonym for rainfall. The phrase 'below normal' corresponds to 'below average'. The word 'below' fits the blank grammatically and adheres to the 'ONE WORD AND/OR A NUMBER' limit.

4. Question 4

   Note completion

   Question

   more brush to act as ______

   Answer

   fuel

   Location

   Passage 1, paragraph 4

   Sentence in the passage

   The unintentional consequence has been to halt the natural eradication of underbrush, now the primary fuel for megafires.

   Explanation

   The note mentions 'more brush' and asks what it acts as. The fourth paragraph discusses the unintentional consequence of stopping wildfires quickly: it "has been to halt the natural eradication of underbrush, now the primary fuel for megafires." 'Underbrush' is the same as 'brush'. The passage explicitly states that underbrush is now the 'primary fuel' for megafires. The word 'fuel' fits the blank and meets the 'ONE WORD AND/OR A NUMBER' limit.

5. Question 5

   Note completion

   Question

   extended fire ______

   Answer

   seasons

   Location

   Passage 1, paragraph 5

   Sentence in the passage

   Second is fire seasons that on average are 78 days longer than they were 20 years ago.

   Explanation

   The note lists factors contributing to increased damage, including 'extended fire __________'. The fifth paragraph lists three other factors. The second factor mentioned is "fire seasons that on average are 78 days longer than they were 20 years ago". This directly supports the idea of 'extended fire seasons'. The word 'seasons' completes the phrase and fits the 'ONE WORD AND/OR A NUMBER' limit.

6. Question 6

   Note completion

   Question

   more building of ______ in vulnerable places

   Answer

   homes/ housing

   Location

   Passage 1, paragraph 5

   Sentence in the passage

   Third is increased construction of homes in wooded areas.

   Explanation

   The note asks about increased building of '__________ in vulnerable places' as a reason for more damage. The fifth paragraph lists factors, and the third factor is "increased construction of homes in wooded areas". The sixth paragraph reinforces this, stating, "We are increasingly building our homes in fire-prone ecosystems". 'Wooded areas' and 'fire-prone ecosystems' are examples of 'vulnerable places'. The phrase 'building of homes' matches 'building of __________'. The word 'homes' fits the blank and the 'ONE WORD AND/OR A NUMBER' limit. 'Housing' would also be acceptable based on other parts of the text referring to 'residential housing'.

7. Question 7

   True / False / Not Given

   Question

   The amount of open space in California has diminished over the last ten years.

   Answer

   TRUE

   Location

   Passage 1, paragraph 7

   Sentence in the passage

   ‘What once was open space is now residential homes providing fuel to make fires burn with greater intensity,’ says Terry McHale of the California Department of Forestry firefighters' union.

   Explanation

   Californian population has grown by more than 600,000 a year for a decade, and a fire union spokesman says land that was once open is now covered by homes. Less open space because of housing growth matches the statement, so it is TRUE.

8. Question 8

   True / False / Not Given

   Question

   Many experts believe California has made little progress in readying itself to fight fires.

   Answer

   FALSE

   Location

   Passage 1, paragraph 8

   Sentence in the passage

   That said, many experts give California high marks for making progress on preparedness in recent years, after some of the largest fires in state history scorched thousands of acres, burned thousands of homes, and killed numerous people.

   Explanation

   The statement claims that many experts believe California has made 'little progress' in preparing for fires. The eighth paragraph begins by stating, 'That said, many experts give California high marks for making progress on preparedness in recent years'. 'High marks' is the opposite of 'little progress'. Therefore, the passage contradicts the statement, making it FALSE.

9. Question 9

   True / False / Not Given

   Question

   Personnel in the past have been criticised for mishandling fire containment.

   Answer

   TRUE

   Location

   Passage 1, paragraph 8

   Sentence in the passage

   Stung in the past by criticism of bungling that allowed fires to spread when they might have been contained, personnel are meeting the peculiar challenges of neighborhood - and canyon- hopping fires better than previously, observers say.

   Explanation

   The statement says that personnel in the past were criticized for mishandling fire containment. The second sentence of the eighth paragraph states that personnel were "Stung in the past by criticism of bungling that allowed fires to spread when they might have been contained". 'Criticism of bungling' means they were criticized for mishandling, and 'allowed fires to spread when they might have been contained' refers to mishandling containment. This directly supports the statement, making it TRUE.

10. Question 10

    True / False / Not Given

    Question

    California has replaced a range of firefighting tools.

    Answer

    TRUE

    Location

    Passage 1, paragraph 9

    Sentence in the passage

    State promises to provide more up-to-date engines, planes, and helicopters to fight fires have been fulfilled.

    Explanation

    The statement claims California has replaced a range of firefighting tools. The ninth paragraph confirms this. Its first sentence states that "State promises to provide more up-to-date engines, planes, and helicopters to fight fires have been fulfilled." The second sentence mentions unions complaining in the past about "dilapidated equipment, old fire engines" and now praising the state's commitment and increased funding. This evidence shows that the state has provided and likely replaced older equipment with new, 'up-to-date' tools, making the statement TRUE.

11. Question 11

    True / False / Not Given

    Question

    More firefighters have been hired to improve fire-fighting capacity.

    Answer

    NOT GIVEN

    Explanation

    The statement claims that more firefighters have been hired. The passage discusses increased funding for firefighting, better equipment (engines, planes, helicopters), improved communication, strategies, and command facilities. It mentions firefighters' unions praising the state's commitment. However, the passage does not contain any information about whether the number of firefighters employed has increased. Therefore, this information is NOT GIVEN.

12. Question 12

    True / False / Not Given

    Question

    Citizens and government groups disapprove of the efforts of different states and agencies working together.

    Answer

    FALSE

    Location

    Passage 1, paragraph 11

    Sentence in the passage

    There is a sense among both government officials and residents that the speed, dedication, and coordination of firefighters from several states and jurisdictions are resulting in greater efficiency than in past ‘siege fire’ situations.

    Explanation

    The statement suggests that citizens and government groups disapprove of different states and agencies working together. The eleventh paragraph states: 'There is a sense among both government officials and residents that the speed, dedication, and coordination of firefighters from several states and jurisdictions are resulting in greater efficiency than in past ‘siege fire’ situations.' 'Government officials and residents' represent government groups and citizens. Their feeling that coordination is resulting in 'greater efficiency' indicates approval, not disapproval. This contradicts the statement, making it FALSE.

13. Question 13

    True / False / Not Given

    Question

    Randy Jacobs believes that loss of life from fires will continue at the same levels, despite changes made.

    Answer

    FALSE

    Location

    Passage 1, paragraph 12

    Sentence in the passage

    ‘Notwithstanding all the damage that will continue to be caused by wildfires, we will no longer suffer the loss of life endured in the past because of the fire prevention and firefighting measures that have been put in place,’ he says.

    Explanation

    The statement claims Randy Jacobs believes the loss of life will continue at the same levels. The final paragraph quotes Randy Jacobs. He states, 'Notwithstanding all the damage that will continue to be caused by wildfires, we will no longer suffer the loss of life endured in the past because of the fire prevention and firefighting measures that have been put in place'. This clearly indicates his belief that loss of life will NOT continue at the same levels ('no longer suffer the loss of life endured in the past'). This directly contradicts the statement, making it FALSE.

Passage 2 · Q14–26 Second nature

1. Question 14

   Summary completion

   Question

   Psychologists have traditionally believed that a personality ______ was impossible and that by a … a person’s character tends to be fixed.

   Answer

   transformation/ change

   Location

   Paragraph A

   Sentence in the passage

   Psychologists have long held that a person's character cannot undergo a transformation in any meaningful way and that the key traits of personality are determined at a very young age.

   Explanation

   The first part of the note states that psychologists traditionally believed a personality ________ was impossible. The first sentence of the passage says: 'Psychologists have long held that a person’s character cannot undergo a transformation in any meaningful way...'. The word 'transformation' from the passage fits the blank, meaning a significant change. This matches the idea of something being 'impossible'. The answer is one word, fitting the limit.

2. Question 15

   Summary completion

   Question

   Psychologists have traditionally believed that a personality … was impossible and that by a ______ a person’s character tends to be fixed.

   Answer

   young age

   Location

   Paragraph A

   Sentence in the passage

   Psychologists have long held that a person's character cannot undergo a transformation in any meaningful way and that the key traits of personality are determined at a very young age.

   Explanation

   The note continues by saying that by a ________ a person's character tends to be fixed. The first sentence of the passage also states that 'the key traits of personality are determined at a very young age'. This phrase 'very young age' directly matches the context of character being fixed early in life. 'Young age' consists of two words, which is within the limit.

3. Question 16

   Summary completion

   Question

   One of the easiest qualities to acquire is ______ However, regardless of the quality, it is necessary to learn a wide variety of different … in order for a new quality to develop; for example, a person must understand and feel some … in order to increase their happiness.

   Answer

   optimism

   Location

   Paragraph A

   Sentence in the passage

   Some qualities are less challenging to develop than others, optimism being one of them.

   Explanation

   The note then discusses positive psychologists and that one of the easiest qualities to acquire is __________. The first sentence of the second paragraph (Section A continues) says: 'Some qualities are less challenging to develop than others, optimism being one of them.' 'Less challenging to develop' is a paraphrase of 'easiest to acquire'. The sentence explicitly names 'optimism' as one of these qualities. The answer is one word, fitting the limit.

4. Question 17

   Summary completion

   Question

   One of the easiest qualities to acquire is … However, regardless of the quality, it is necessary to learn a wide variety of different ______ in order for a new quality to develop; for example, a person must understand and feel some … in order to increase their happiness.

   Answer

   skills/ techniques

   Location

   Paragraph A

   Sentence in the passage

   However, developing qualities requires mastering a range of skills which are diverse and sometimes surprising.

   Explanation

   The note states that regardless of the quality, it is necessary to learn a wide variety of different __________ in order for a new quality to develop. The second sentence of the second paragraph (Section A) says: 'However, developing qualities requires mastering a range of skills which are diverse and sometimes surprising.' The phrase 'mastering a range of skills which are diverse' corresponds to learning a 'wide variety of different __________'. The word 'skills' fits perfectly. The answer is one word, fitting the limit.

5. Question 18

   Summary completion

   Question

   One of the easiest qualities to acquire is … However, regardless of the quality, it is necessary to learn a wide variety of different … in order for a new quality to develop; for example, a person must understand and feel some ______ in order to increase their happiness.

   Answer

   negative emotions/ feelings

   Location

   Paragraph A

   Sentence in the passage

   For example, to bring more joy and passion into your life, you must be open to experiencing negative emotions.

   Explanation

   The final part of the note gives an example: a person must understand and feel some __________ in order to increase their happiness. The third sentence of the second paragraph (Section A) provides this example: 'For example, to bring more joy and passion into your life, you must be open to experiencing negative emotions.' The phrase 'bring more joy and passion into your life' relates to increasing happiness. It states that one 'must be open to experiencing negative emotions'. The phrase 'negative emotions' fits the blank. It consists of two words, within the limit.

6. Question 19

   Matching features

   Question

   People must accept that they do not know much when first trying something new.

   Answer

   E

   Location

   Paragraph F

   Sentence in the passage

   Psychologist Todd Kashdan has this advice for those people taking up a new passion: 'As a newcomer, you also have to tolerate and laugh at your own ignorance.

   Explanation

   The statement says people must accept their lack of knowledge when starting something new. In Section F, psychologist Todd Kashdan gives advice for people taking up a new passion. The third sentence of the seventh paragraph (Section F) quotes him saying: 'As a newcomer, you also have to tolerate and laugh at your own ignorance.' 'As a newcomer' implies first trying something new, and 'tolerate and laugh at your own ignorance' means accepting they do not know much. This matches the statement and identifies Todd Kashdan (Option E) as the source.

7. Question 20

   Matching features

   Question

   It is important for people to actively notice when good things happen.

   Answer

   C

   Location

   Paragraph D

   Sentence in the passage

   She recommends you train yourself to pay attention to good fortune by writing down three positive things that come about each day.

   Explanation

   The statement suggests it's important to actively notice good things. In Section D, Suzanne Segerstrom, a professor of psychology, discusses increasing optimism. The second sentence of the fifth paragraph (Section D) states: 'She recommends you train yourself to pay attention to good fortune by writing down three positive things that come about each day.' 'Train yourself to pay attention to good fortune' is a direct instruction to actively notice good things. This advice is given by Suzanne Segerstrom (Option C).

8. Question 21

   Matching features

   Question

   Courage can be learned once its origins in a sense of responsibility are understood.

   Answer

   G

   Location

   Paragraph H

   Sentence in the passage

   According to Cynthia Pury, a psychologist at Clemson University, Pedeleose's story proves the point that courage is not motivated by fearlessness, but by moral obligation.

   Explanation

   The statement links courage to being learned and originating from a sense of responsibility. Section H discusses courage. The fifth sentence of the tenth paragraph (Section H) quotes Cynthia Pury saying: 'According to Cynthia Pury... courage is not motivated by fearlessness, but by moral obligation.' 'Moral obligation' is a strong sense of responsibility. The very next sentence states: 'Pury also believes that people can acquire courage.' This combination of points from Cynthia Pury (Option G) directly supports the statement that courage can be learned and is based on a sense of responsibility ('moral obligation').

9. Question 22

   Matching features

   Question

   It is possible to overcome shyness when faced with the need to speak in public.

   Answer

   A

   Location

   Paragraph B

   Sentence in the passage

   Inherently introverted, he realised early on that as an academic, his reticence would prove disastrous in the lecture hall.

   Explanation

   The statement talks about overcoming shyness (reticence/introversion) when speaking publicly (in a lecture hall). In Section B, Christopher Peterson discusses changing personality traits. The second sentence of the third paragraph (Section B) says he was 'Inherently introverted' (shy/reticent) and realised this would be 'disastrous in the lecture hall' (public speaking). The third sentence states he 'learned to be more outgoing and to entertain his classes', showing he overcame this when required to speak publicly. Christopher Peterson (Option A) is the person described.

10. Question 23

    Matching information

    Question

    a mention of how rational thinking enabled someone to achieve physical goals

    Answer

    E

    Location

    Paragraph E

    Sentence in the passage

    Streeter learned to untangle her fears from her judgment of what her body and mind could do.

    Explanation

    The question asks for mention of how rational thinking helped achieve physical goals. The correct answer is Section E. According to the passage's structure (`sectionrange`), Section E corresponds to the sixth paragraph of the passage. This section discusses Tanya Streeter, a freediver (physical goal). The fifth sentence of this paragraph states: 'Streeter learned to untangle her fears from her judgment of what her body and mind could do.' This describes using rational thinking ('judgment') to overcome emotional barriers ('fears') to achieve physical limits ('what her body and mind could do'). The following sentence reinforces this by stating the limit wasn't where she emotionally 'thought' it was, but higher based on reality.

11. Question 24

    Matching information

    Question

    an account of how someone overcame a sad experience

    Answer

    C

    Location

    Paragraph C

    Sentence in the passage

    He was preparing for university, when he had an accident that put an end to his sports career.

    Explanation

    The question asks for an account of overcoming a sad experience. The correct answer is Section C. Section C corresponds to the fourth paragraph. This section describes David Fajgenbaum, who had a sad experience: an accident ending his sports career, leading to physical rehabilitation and depression. The paragraph details how he overcame this by launching a support group to help himself and others, taking action despite his pain.

12. Question 25

    Matching information

    Question

    a description of how someone decided to rethink their academic career path

    Answer

    G

    Location

    Paragraph G

    Sentence in the passage

    In 2004, physician-scientist Mauro Zappaterra began his PhD research at Harvard Medical School.

    Explanation

    The question asks for a description of rethinking an academic career path. The correct answer is Section G. Section G corresponds to the eighth paragraph. This paragraph discusses Mauro Zappaterra, a physician-scientist doing PhD research at Harvard. It states he was 'miserable' because his research wasn't compatible with his interests. He took a break, learned about alternative techniques, and then 'switched labs', indicating a significant change and rethinking of his academic research path.

13. Question 26

    Matching information

    Question

    an example of how someone risked his career out of a sense of duty

    Answer

    H

    Location

    Paragraph H

    Sentence in the passage

    For marketing executive Kenneth Pedeleose, it meant speaking out against something he thought was ethically wrong.

    Explanation

    The question asks for an example of someone risking their career due to a sense of duty. The correct answer is Section H. Section H corresponds to the tenth paragraph. This section provides the example of Kenneth Pedeleose, a marketing executive. It describes him speaking out against unethical behaviour (manager intimidating staff), documenting it, and taking the evidence to a senior director, explicitly stating he knew 'his own job security would be threatened'. This action, taken despite personal risk, stems from a sense of duty regarding ethical behaviour and staff well-being, which Cynthia Pury later labels a 'moral obligation'.

Passage 3 · Q27–40 When evolution runs backwards

1. Question 27

   Multiple choice

   Question

   When discussing the theory developed by Louis Dollo, the writer says that

   Answer

   C

   Location

   Passage 3, paragraph 3

   Sentence in the passage

   Early 20th-century biologists came to a similar conclusion, though they qualified it in terms of probability, stating that there is no reason why evolution cannot run backwards -it is just very unlikely.

   Explanation

   The question asks about the writer's description of Louis Dollo's theory. The third paragraph, which discusses Dollo's law, states in its third sentence: 'Early 20th-century biologists came to a similar conclusion, though they qualified it in terms of probability, stating that there is no reason why evolution cannot run backwards -it is just very unlikely.' This shows that biologists in the early 20th century took Dollo's principle and modified it by adding the element of probability (it's unlikely, not impossible). This directly supports option C.

2. Question 28

   Multiple choice

   Question

   The humpback whale caught off Vancouver Island is mentioned because of

   Answer

   D

   Location

   Passage 3, paragraph 4

   Sentence in the passage

   In 1919, for example, a humpback whale with a pair of leglike appendages over a metre long, complete with a full set of limb bones, was caught off Vancouver Island in Canada.

   Explanation

   The passage mentions the humpback whale with leg-like appendages as an example of an exception to Dollo's law (paragraph 3, sentence 2). The reason it is discussed is explicitly stated in the following sentence (paragraph 3, sentence 3): 'Explorer Roy Chapman Andrews argued at the time that the whale must be a throwback to a land-living ancestor.' This highlights the *explanation* offered for the whale's unusual features (the appendages), supporting option D.

3. Question 29

   Multiple choice

   Question

   What is said about ‘silent genes’?

   Answer

   C

   Location

   Passage 3, paragraph 6

   Sentence in the passage

   If these silent genes are somehow switched back on, they argued, long-lost traits could reappear.

   Explanation

   The question asks about 'silent genes'. Paragraph 5 discusses Rudolf Raff's research into this topic. The third sentence of this paragraph states: 'If these silent genes are somehow switched back on, they argued, long-lost traits could reappear.' This directly indicates that silent genes are hypothesized to cause the 're-emergence of certain characteristics' (long-lost traits), confirming option C.

4. Question 30

   Multiple choice

   Question

   The writer mentions the mole salamander because

   Answer

   B

   Location

   Passage 3, paragraph 8

   Sentence in the passage

   As a possible example, the team pointed to the mole salamanders of Mexico and California.

   Explanation

   The writer introduces the mole salamanders immediately after detailing Raff's theory about silent genes and their potential lifespan (paragraph 6). The first sentence of paragraph 7 explicitly states: 'As a possible example, the team pointed to the mole salamanders of Mexico and California.' This indicates the salamanders are used to illustrate or support Raff's theory. The final sentence of the paragraph further reinforces this: 'The salamander example fits with Raff’s 10million-year time frame.' This confirms the example is used to suggest that Raff's theory is correct or at least plausible within its proposed timescale.

5. Question 31

   Multiple choice

   Question

   Which of the following does Wagner claim?

   Answer

   A

   Location

   Passage 3, paragraph 9

   Sentence in the passage

   According to his analysis of the Bachia family tree, the toed species re-evolved toes from toeless ancestors and, what is more, digit loss and gain has occurred on more than one occasion over tens of millions of years.

   Explanation

   The question asks about Gunter Wagner's claims regarding Bachia lizards. Paragraph 8 details Wagner's research. The final sentence of this paragraph states: 'According to his analysis of the Bachia family tree, the toed species re-evolved toes from toeless ancestors and, what is more, digit loss and gain has occurred on more than one occasion over tens of millions of years.' This clearly indicates Wagner claims that features (digits/toes) have been 'lost and regained' ('digit loss and gain') 'on more than one occasion', which aligns perfectly with option A.

6. Question 32

   Matching sentence endings

   Question

   For a long time biologists rejected

   Answer

   F

   Location

   Passage 3, paragraph 1

   Sentence in the passage

   For the better part of a century, most biologists have been reluctant to use those words, mindful of a principle of evolution that says ‘evolution cannot run backwards.

   Explanation

   The sentence stem is 'For a long time biologists rejected'. The first paragraph (sentence 1) mentions biologists' reluctance to use 'evolutionary throwback' words because evolution supposedly 'cannot run backwards'. The third paragraph elaborates on this, stating that Dollo proposed irreversibility (sentence 1) and 'the idea of irreversibility in evolution stuck' (sentence 4). Rejecting the idea that evolution 'cannot run backwards' is equivalent to rejecting 'the possibility of evolution being reversible'. Thus, option F correctly completes the sentence based on the passage.

7. Question 33

   Matching sentence endings

   Question

   Opposing views on evolutionary throwbacks are represented by

   Answer

   G

   Location

   Passage 3, paragraph 2

   Sentence in the passage

   The word has ugly connotations thanks largely to Cesare Lombroso, a 19th-century Italian medic who argued that criminals were born not made and could be identified by certain physical features that were throwbacks to a primitive, sub-human state.

   Explanation

   The sentence stem is 'Opposing views on evolutionary throwbacks are represented by'. Paragraph 1 discusses Cesare Lombroso's view that certain criminal features were 'throwbacks' (sentence 1), giving the term 'ugly connotations'. Paragraph 2 introduces Louis Dollo by contrasting his work with Lombroso's: 'While Lombroso was measuring criminals, a Belgian palaeontologist called Louis Dollo was studying fossil records and coming to the opposite conclusion.' (sentence 0). Dollo's conclusion, that evolution was irreversible, was directly 'opposite' to the idea of throwbacks implied by Lombroso's view. Therefore, Lombroso's view and Dollo's findings represent opposing perspectives on the possibility or meaning of evolutionary throwbacks. Option G fits this.

8. Question 34

   Matching sentence endings

   Question

   Examples of evolutionary throwbacks have led to

   Answer

   A

   Location

   Passage 3, paragraph 5

   Sentence in the passage

   Since then, so many other examples have been discovered that it no longer makes sense to say that evolution is as good as irreversible.

   Explanation

   The sentence stem is 'Examples of evolutionary throwbacks have led to'. Paragraph 4 discusses how numerous examples of exceptions to Dollo's law have emerged (sentence 0). The very next sentence states: 'And this poses a puzzle: how can characteristics that disappeared millions of years ago suddenly reappear?' (sentence 1). The 'puzzle' is a question arising directly from the existence of these examples of throwbacks. The question is about 'how certain long-lost traits' (characteristics that disappeared millions of years ago) 'could reappear'. This matches option A.

9. Question 35

   Matching sentence endings

   Question

   The shark and killer whale are mentioned to exemplify

   Answer

   B

   Location

   Passage 3, paragraph 10

   Sentence in the passage

   One possibility is that these traits are lost and then simply reappear, in much the same way that similar structures can independently arise in unrelated species, such as the dorsal fins of sharks and killer whales.

   Explanation

   The sentence stem is 'The shark and killer whale are mentioned to exemplify'. Paragraph 9 discusses possible explanations for the reappearance of lost traits. The second sentence of this paragraph uses sharks and killer whales as an analogy: 'in much the same way that similar structures can independently arise in unrelated species, such as the dorsal fins of sharks and killer whales'. The dorsal fin is a 'particular feature' that occurs in two different, unrelated species ('sharks and killer whales'). Thus, they are used to exemplify 'the occurrence of a particular feature in different species' (similar structures arising independently). This matches option B.

10. Question 36

    Matching sentence endings

    Question

    One explanation for the findings of Wagner’s research is

    Answer

    D

    Location

    Passage 3, paragraph 10

    Sentence in the passage

    Another more intriguing possibility is that the genetic information needed to make toes somehow survived for tens or perhaps hundreds of millions of years in the lizards and was reactivated.

    Explanation

    The sentence stem is 'One explanation for the findings of Wagner’s research is'. Paragraph 9 discusses possible explanations for Wagner's observation that traits (toes) reappeared over very long timescales. The third sentence of this paragraph presents 'Another more intriguing possibility' which is 'that the genetic information needed to make toes somehow survived... and was reactivated.' 'Genetic information needed to make toes' represents 'certain genetic information'. Its 'survival' is its 'continued existence'. This explanation directly relates to Wagner's findings about traits reappearing over tens of millions of years. Thus, option D correctly completes the sentence.

11. Question 37

    Yes / No / Not Given

    Question

    Wagner was the first person to do research on South American lizards.

    Answer

    NOT GIVEN

    Explanation

    The passage mentions Gunter Wagner's research on a group of South American lizards called Bachia (paragraph 8, sentence 1). However, it only states that he 'reported some work' on them and analysed their family tree. It does not provide any information indicating whether he was the very first person to conduct research on South American lizards in general or even specifically on this group. Therefore, this information is not present in the passage.

12. Question 38

    Yes / No / Not Given

    Question

    Wagner believes that Bachia lizards with toes had toeless ancestors.

    Answer

    YES

    Location

    Passage 3, paragraph 9

    Sentence in the passage

    According to his analysis of the Bachia family tree, the toed species re-evolved toes from toeless ancestors and, what is more, digit loss and gain has occurred on more than one occasion over tens of millions of years.

    Explanation

    The statement claims that Wagner believes Bachia lizards with toes evolved from toeless ancestors. Paragraph 8 discusses Wagner's research on Bachia lizards. Sentence 5 explicitly states: 'According to his analysis of the Bachia family tree, the toed species re-evolved toes from toeless ancestors'. This confirms that Wagner's belief, based on his analysis, is exactly what is stated in the question. Therefore, the answer is YES.

13. Question 39

    Yes / No / Not Given

    Question

    The temporary occurrence of long-lost traits in embryos is rare.

    Answer

    NO

    Location

    Passage 3, paragraph 11

    Sentence in the passage

    Early embryos of many species develop ancestral features.

    Explanation

    The statement claims that the temporary occurrence of long-lost traits in embryos is rare. Paragraph 10 discusses another possible explanation for throwbacks, involving embryonic development. Sentence 2 states: 'Early embryos of many species develop ancestral features.' The phrase 'many species' is the opposite of 'rare'. It implies this is a common phenomenon across a wide range of species. Therefore, the passage contradicts the statement, and the answer is NO.

14. Question 40

    Yes / No / Not Given

    Question

    Evolutionary throwbacks might be caused by developmental problems in the womb.

    Answer

    YES

    Location

    Passage 3, paragraph 11

    Sentence in the passage

    The answer may lie in the womb.

    Explanation

    The statement suggests that evolutionary throwbacks might result from developmental problems in the womb. Paragraph 10 presents an alternative explanation for throwbacks, stating 'The answer may lie in the womb.' (sentence 1). It explains that embryonic development normally involves losing ancestral features (sentence 4). Sentence 5 says: 'If for any reason this does not happen, the ancestral feature may not disappear, leading to an atavism.' The phrase 'If for any reason this does not happen' in the context of developmental programs losing features during embryonic development ('in the womb') directly implies that a failure in this normal developmental process can lead to a throwback (atavism). A failure in a developmental program is a 'developmental problem'. Therefore, the passage supports the idea that developmental problems in the womb might cause throwbacks. The answer is YES.