A shame, then, that he is now, in the words of Monty Python, an ex-parrot.
By the end, said Dr Pepperberg, Alex had the intelligence of a five-year-old child and had not reached his full potential. He had a vocabulary of 150 words. He knew the names of 50 objects and could, in addition, describe their colours, shapes and the materials they were made from. He could answer questions about objects’ properties, even when he had not seen that particular combination of properties before. He could ask for things – and would reject a proffered item and ask again if it was not what he wanted. He understood, and could discuss, the concepts of “bigger”, “smaller”, “same” and “different”. And he could count up to six, including the number zero (and was grappling with the concept of “seven” when he died). He even knew when and how to apologise if he annoyed Dr Pepperberg or her collaborators.
Its just amazing.