27. What is the writer’s purpose in the first paragraph?

• A. to reject a long-held belief

• B. to criticise a common activity

• C. to express concern about a change

• D. to support a distinction between species

28. According to the second paragraph, ‘good service’ by cleaner wrasse involves the removal of

• A. mucus but not body tissue.

• B. parasites but not other substances.

• C. mucus in return for other benefits.

• D. parasites in return for other types of food.

29. According to the third paragraph, what conclusion did Bshary reach about Red Sea cleaner wrasse?

• A. They are less likely to harm loyal clients.

• B. They may refuse clients of certain species.

• C. They compete with one another to attract more clients.

• D. They provide better service to encourage clients to return.

30. The writer refers to research around Lizard Island to make the point that clients described as ‘visitor fish’ may

• A. be vulnerable to changes in climate conditions.

• B. be able to control the activities of other fish.

• C. receive fewer benefits if cleaner numbers fall.

• D. be in danger of attack from cleaners in that area.

31. In the fifth paragraph, Bshary says that it will probably be necessary to rethink ideas about

• A. the power of animal brains.

• B. the structure of animal brains.

• C. the development of animal brains.

• D. the number of animals with large brains.

Questions 32–35

Complete the summary using the list of words, A–F below.
Write the correct letter, A–F, in boxes 32–35 on your answer sheet.

Toby Kiers’ research on biological trading

Toby Kiers studies the way that mycorrhizal fungi and plants interact, each providing the other with necessary 32 ________​ ​ (a)   ​ ​ . She found the structure of the fungal network and its link with the plants allow them to make similar 33 ________ ​ (b)   to humans. It also appears that the fungi avoid trading with plants that may not be 34 ________ ​ (c)   of the required product, and that they may create 35 ________ (d)   of the substance they are trading so that its value increases.

• chemical elements
• trading decisions
• good suppliers
• deliberate shortage
•  business prioritie
• economic indicators

36. Human use of money is an example of simple economic behaviour.

• TRUE

• FALSE

• NOT GIVEN

37. 37.Primate trading methods have been studied for longer than those of other types of organism.

• TRUE

• FALSE

• NOT GIVEN

38. 38. Fungal-plant systems provide useful and detailed information on trading procedures.

• TRUE

• FALSE

• NOT GIVEN

39. 39. Feelings and emotions may affect business practices among humans.

• TRUE

• FALSE

• NOT GIVEN