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"THAT DAMN BIRD"

For the past 26 years I've been studying the cognitive and communicative abilities of Grey parrots. My oldest bird, Alex, can identify about 50 different objects using English labels. He can also label seven colors, five shapes, and quantities up to and including six. He has functional use of phrases like "I want X" and "I wanna go Y", where X and Y, respectively, are object or location labels. He combines these labels to identify, refuse, request and categorize more than a hundred different items. He has concepts of bigger and smaller, of category, of sameness and difference, of absence of information, and of number.

We test him not only through direct questions about these concepts (e.g., "What color bigger?" for two differently sized and colored blocks), but also by using questions that involve complex structures—recursive phrases or conjunctive, recursive phrases—such as, "What object is green and three-corner?"; he answers all these questions with about 80% accuracy. We think the reason he doesn't achieve 100% accuracy is boredom; he seems to get tired of repeatedly telling us about colors and shapes and materials. For example, he sometimes will state every color but the correct one, behavior that suggests that he is carefully avoiding the right answer; statistically, he couldn't do that by chance.

He also understands categories in terms of hierarchical levels, so he knows that there's this weird (to him) sound called "color" and under that weird sound are grouped all these other sounds called "red," "blue," "green," "yellow," "orange," etc. that relate to a specific set of physical attributes of objects. Similarly, he understands there is another weird sound, "shape," and under that sound there are the other sound patterns "two-", "three-", "four-", "five-", and "six-corner" that relate to different physical attributes of the same objects. We can teach him new ways of categorizing items. If he's already learned to categorize items by color and shape, we can then ask him to categorize them by number. Furthermore, Alex demonstrates a certain level of intentionality involving requests. If he says that he wants grape and you give him a banana, you are going to end up wearing the banana....