Evaluate the study by Hassett et al. (monkey toy preferences) in terms of two strengths and two weaknesses. At least one of your evaluation points must be about ethics.

Mark scheme

Marking points from the official mark scheme (Feb/Mar 2024). The mark or mark type is shown in brackets.

1. [5] (Level 5) Very good evaluation including the named issue. Thoroughly addresses both strengths and both weaknesses in detail. Selection of evidence is very thorough and effective.
2. [2-3] (Strength - Standardisation/Reliability) The study followed a standardised procedure, such as offering all monkeys the same pairs of toys for 30 seconds, making it easier to replicate and increasing its reliability.
3. [2-3] (Strength - Internal Validity/Observations) The use of video cameras for observations allowed for objective data collection and potential inter-rater reliability checks, increasing the internal validity of the preference recordings.
4. [2-3] (Weakness - External Validity/Sample Generalisability) The sample only had 34 rhesus monkeys, all captive-bred and housed in an enclosure. This small, specific sample may limit the generalisability of the findings to a wider population of rhesus monkeys, particularly those in the wild where toy choice and environmental factors differ significantly.
5. [2-3] (Weakness - Ethics/Housing) The study raises ethical concerns regarding housing. While the monkeys were housed in a large 25x25-foot enclosure and were socially housed within their troop, living in captivity may still impact their behaviour and well-being, potentially making their toy preferences unnatural compared to wild monkeys.