From the Pepperberg study (parrot learning):

Mark scheme

Marking points from the official mark scheme (Feb/Mar 2018). The mark or mark type is shown in brackets.

1. [1 mark for the result 1 mark for the use of data] Alex performed well above chance in this test (1 mark) Alex performed worse for familiar than for novel objects (1 mark) Alex's score was 76.6% (99/129) for all trials (2 marks) Alex's score was 69.7% (69/99) on first-trial-only (2 marks)
2. [2 marks - full answer 1 mark - partial/brief answer] That an avian subject, an African Grey parrot, showed symbolic comprehension/cognitive ability of the concept same/different. (2 marks) Because his scores on all tests (including first trial analyses) were significantly above chance this suggests that he understood what the questions were asking. This was then shown via the probe questioning. (2 marks) It would therefore appear that symbolic representation, in this case of same/different, is not exclusive to primates. (2 marks) The study showed that he could comprehend same/different. (1 mark) Not only primates can understand same/different. (1 mark)