Dr Paul Marsden is managing editor of the Journal of Memetics, the study of infectious ideas. He suggests that this type of group behaviour may have had a role to play in human evolution. In our distant past, one individual scratching would have alerted others that there were biting insects or parasites present. This would prime them to scratch itches of their own. Anyone who has been bitten several times by mosquitoes before they realized it will recognize the evolutionary value of this kind of advance warning. The outbreak of mass scratching may also promote mutual grooming, which is important in the necessary bonding of primate groups.
The problem comes when the reflex contagion is not related to a real threat. Normally, everyone would soon stop scratching, but people may unconsciously exaggerate symptoms to gain attention, or because it gets them a break from unappealing work. The lab workers were scanners, who spent the day laboriously examining the results of bubble-chamber tests; textile workers and clerical staff poring over records would also have found what they had to do quite tedious. Add the factor that skin conditions are notoriously susceptible to psychological influence, and it is easy to see how a group dynamic can keep the illusory parasites going.
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Question Focus: Identifying the starting action in the diagram that triggers the group response
Correct Answer: individual scratching
Why this is correct: Look at the first box in the diagram showing the initial action. The passage says one individual scratching started the chain reaction, so the diagram label must copy these exact words.
Passage Reference: In our distant past, one individual scratching would have alerted others that there were biting insects or parasites present. This would prime them to scratch itches of their own.
Common Mistake: Students sometimes write scratching only. This is incomplete because the passage specifies one individual scratching. This is a partial truth trap.
Paraphrasing: Passage: 'one individual scratching' = Diagram: 'starting action'
Tips: For diagram questions, identify whether the gap needs an action or a result before choosing words.
Key Vocabulary:
- individual = one person
- distant past = long ago
Question Focus: Understanding the immediate effect of the first action
Correct Answer: alerted others
Passage Reference: In our distant past, one individual scratching would have alerted others that there were biting insects or parasites present.
Why this is correct: The second box in the diagram shows what happens because of the scratching. The passage clearly states that it alerted others, which fits the cause-and-effect flow.
Common Mistake: Some students write warned others. This changes the wording and is not copied from the passage. This is a synonym trap.
Paraphrasing: Passage: 'alerted others' = Diagram: 'made other people aware'
Tips: Always copy the exact verb from the passage. Do not replace it with your own synonym.
Key Vocabulary:
- alert = warn
- parasites = small harmful creatures
Question Focus: Identifying a secondary social effect shown in the diagram
Correct Answer: grooming
Passage Reference: The outbreak of mass scratching may also promote mutual grooming, which is important in the necessary bonding of primate groups.
Why this is correct: The diagram shows an outcome related to group behavior. The passage says mass scratching may promote mutual grooming, so the key word to copy is grooming.
Common Mistake: Students may write mutual grooming, which is correct in meaning but may not fit the single gap if only one word is needed. This is a grammar fit trap.
Paraphrasing: Passage: 'mutual grooming' = Diagram: 'group activity'
Tips: Check how many words the gap can realistically hold on the diagram before copying.
Key Vocabulary:
- outbreak = sudden spread
- grooming = cleaning each other
Question Focus: Recognising the final social benefit in the diagram flow
Correct Answer: bonding
Passage Reference: The outbreak of mass scratching may also promote mutual grooming, which is important in the necessary bonding of primate groups.
Why this is correct: The last box in the diagram shows the long-term group result. The passage explains that grooming is important for bonding, so this word completes the process.
Common Mistake: Some students write relationships or unity, which are not in the passage. You must copy the exact word. This is a synonym trap.
Paraphrasing: Passage: 'bonding of primate groups' = Diagram: 'stronger group ties'
Tips: Final boxes in diagrams often show results or benefits. Look for conclusion words in the passage.
Key Vocabulary:
- bonding = forming close relationships
- primate = monkey or human-like animal
General Tips:
- Diagram completion answers follow the passage order. Find the first answer, then move forward.
- Never change the wording. Copy the exact word or words from the passage.
- Check the word limit carefully. More than two words is automatically wrong.
- Look at what the diagram box represents - action, result, or effect - before choosing the answer.
- Use grammar clues and diagram flow arrows to predict what type of word is missing.
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