Two friends, Haji and Dottie, are discussing the ethics of the study by Yamamoto et al. (chimpanzee helping). Haji thinks the study is ethical but Dottie thinks the study is not ethical. Explain one reason why Haji is correct and one reason why Dottie is correct, using evidence from this study.

Mark scheme

Marking points from the official mark scheme (May/June 2023). The mark or mark type is shown in brackets.

1. 3 marks for Haji. 1 mark per correct point made. 1 mark available for naming guideline.
2. 3 marks for Dottie. 1 mark per correct point made. 1 mark available for naming guideline.
3. e.g., Haji The smallest number of animals should be used in research (1 mark: naming guideline) in order to meet the aims and goals of the study (1 mark). Yamamoto only used five chimpanzees / five kin pairs of chimpanzees in the study (1 mark).
4. The chimpanzees did not experience any deprivation (1 mark: reason) as they had access to food and water all of the time (1 mark).
5. e.g., Dottie Behaviours cannot be controlled by the use of rewards only (1 mark: naming guideline). In this case it could be argued that one chimpanzee did get a reward at the expense of the other (1 mark) which meant that the chimpanzee who did not receive a reward was stressed (1 mark).
6. The chimpanzees may have felt some distress (1 mark: reason) if they could not figure out which tool was the best choice (1 mark).