In the study by Pepperberg (parrot learning) the sample was only one parrot, Alex. This parrot could have differed from other parrots of the same species. Explain how two possible differences could have affected Pepperberg's study. 1 2

Mark scheme

Marking points from the official mark scheme (May/June 2021). The mark or mark type is shown in brackets.

1. [2] Alex could have been more intelligent; Which would have made grey parrots seem that they could understand concepts when they couldn't;
2. [2] Alex could have been less intelligent; Which would have made grey parrots seem slower to understand concepts than they really are;
3. [2] Alex was kept in a laboratory / wasn't in the wild; So had experiences that would have made his responses different from wild parrots;
4. [2] Alex had already been studied (for years) / had heard a lot of human speech; So had experiences that would have made his responses different from wild parrots; So he might have been less frightened of shapes / more familiar with different materials so perform better;