One of my students was cleaning up the laboratory; we recycle whatever we can, so she was collecting all the empty bottles, throwing them in a bin, separating out the caps and putting them on the counter where Griffin, an African grey parrot, was sitting. She called me over and said, "You told me that parrots are destructive foragers and that they don't really put things together, so come here and take a look." There was Griffin, taking smaller caps and putting them into bigger caps, then picking up the pairs and throwing them off the side of the counter. This incident occurred at about the same time that he was saying things like "want walnut," "green grape," and other 2-word combinations of that nature.
We took a deep breath and said, "Okay, a nice anecdote but we must look at the behaviour scientifically." We started examining 3-level combinations. We began by giving Griffin lots of different bottle caps, jar lids and things that he could put together, and also training him on a very small number of 3-label combinations - 2-corner wood, 2-corner paper, 5-corner wood, 5-corner paper - to give him the idea of combining labels. We started the experiment around June, and months went by and he wasn't putting together more than 2 bottle caps or lids and wasn't saying any 3-label combinations. But we kept working. Then in February, within the space of about 10 days, he started making 3-object combinations and putting 3 labels together.
It was as though something in his brain had had to mature or some wiring had to develop. Interestingly, over the course of the experiment, the percentage of 3-label combinations and the percentage of 3-item combinations were the same: about 6 - 10%. He wasn't very proficient at any of the triple combinations but he was forming them. He continued primarily to utter 2-label combinations and construct 2-object combinations; he succeeded on something like 200 of 210 two-object attempts, performing easily and correctly. The fascinating point was that of all of his vocal 3-label combinations, he used only one on which he had been trained. The rest of his 3-label utterances were ones he put together himself, like "want green nut" or "wanna go chair." He used 14 representative 3-label combinations and repeated each of those many times.
What the data suggest to me is that if one starts with a brain of a certain complexity and gives it enough social and ecological support, that brain will develop at least the building blocks of a complex communication system. Why is this material important as well as fascinating? Because it suggests that to understand the evolutionary bases for cognition, we must also examine cognition in creatures quite removed from humans. Other forms of cognition exist that are as interesting, as important, and that might have similar evolutionary bases.
Parrots live in an environment that both matches and differs from that of apes. With respect to similarities, birds have to deal with a complex ecology. Grey parrots, for example, forage up to 60 kilometers a day. They are at least as long-lived as apes, so they must keep track of changes in the rain forest and the savanne over the course of 30 to 60 years - both seasonal changes and long-term environmental changes. Greys live in large flocks. They separate out into pairs during breeding seasons. We don't know much about their social strata, but they definitely defend their nest areas from other pairs.
When I first wanted to begin this research, I submitted a grant proposal to NIH, and the panel came back with reviews essentially asking me what I was smoking, because nobody thought birds could do anything remotely like what I was proposing. So I worked with undergraduate volunteers, with my friends' high-school children, and showed that parrots could referentially label objects. I resubmitted the grant to NSF. I got a very small amount of funding. When it came up for renewal, the reviewers said, "That's fine, but do parrots understand categorisation?" My students and I then demonstrated that Alex could label an object by its colour, its shape, and its material; we showed an understanding of hierarchical categories. Nobody thought birds could do that. Then my critics said, "But parrots don't have concepts of 'same' and 'different' the way chimps do." So we made Alex do this task "backwards and in heels": the chimps had only to designate whether 2 objects were the same or different; Alex had to look at 2 items and tell you the label of the category that was the same or different, that is, with respect to colour, shape, or material. We'd give him two wooden squares of different colours, and ask "What's different?", or a yellow paper triangle and a blue wooden one and ask "What's same?"
Then we started looking at concepts of absence, because people said that animals don't have such a concept. I argued that of course they have to respond to absence of information in the wild: they understand that "if my neighbour bird is not singing, it is probably gone and I can invade its territory." So we demonstrated that Alex could respond "none" if nothing was same or different about two items.
The same issues arose with concepts of number. Many scientists felt that animals don't have a number sense because they don't understand abstract representations and relational concepts. We therefore did a series of studies on number, showing that Alex could, for example, look at a tray of intermingled red and blue balls and blocks and tell us how many blue blocks were on the tray (that is, ignore the red and blue balls and the red blocks, and focus on one subset of items); a 4-year-old child has problems with such a task. Every time that people said that parrots can't do something, I've been able to show that they have some ability with respect to the concept in question, and in some cases I've been able to show more complex understanding than other researchers have been able to show in the primates.
My research is important for the pet industry. What I've tried to explain to parrot owners is that what they have in a cage in their living room is a creature with the sentience of a 4- to 6-year-old child. I try to convince them that you can't just lock it in a cage for 8 hours a day without any kind of interaction. I don't mean just interpersonal interaction, or having other birds around; parrots have to be intellectually challenged. In the wild they are constantly challenged - challenged to find food, challenged to avoid predators, and challenged by the intra-flock interactions. In contrast, what does a pet do? The bird sits alone in a cage all day, with ample food and water in nice accessible cups, and vegetates. Some birds in such situations pluck their feathers; they scream, they bite - they act in ways similar to those of a 4-year-old having a temper tantrum because it had been left it alone in a playpen for 8 hours with maybe one toy and some snacks. I've tried to help these people understand what they are getting themselves into, and hopefully have convinced them to enrich the lives of these birds as much as possible.
One of the other things to remember when you have a pet parrot is that this bird is a flock creature. One parrot in the wild is a dead parrot - it can't forage and look for predators at the same time. So when you have one bird in your house, or even two birds of separate species, you have a bird that is seeking companions as well as stimulation.
One of the things we tried to do was to devise different types of computer-based enrichment programs for birds. We created something called "InterPet Explorer," which was a modified web browser. The bird had 4 choices of input: it could see video, listen to music, see pictures, or play a game. Within each of those categories were 4 choices. Under the music selection, for example, the bird could choose clips of rock, country, classical or jazz. Alex would play with this system for about an hour in the morning before we came into the lab. At first he interacted with it a lot, then seemed to lose interest; the students were concerned that the system was a failure. I asked them, "How often are you changing content?" They then reorganised the system to use different channels of Internet radio so that Alex had something different whenever he clicked a choice, and his interest shot back up.
Ben Resner and Bruce Blumberg created "Rover@Home," in which you could play with your dog over the Internet while you were at work. These are examples of the kinds of interactive systems we were trying to develop, so you could sit at your desk during your coffee break and use cameras and computers to connect with your animal. I hoped it would be the start of a serious research program, not just for pets, but also to enrich the lives of various species in zoos and even research subjects in animal care facilities. For a lot of reasons, it didn't happen. The idea is still out there, though, and I hope somebody will continue it one day.
There are many studies my students and I still want to do with our parrots. For example, we want to look at spatial concepts. For humans, "over" and "under" are pretty standard concepts. Parrots, in contrast, are more 3-dimensional. As they fly, within a second what is over them is under and vice versa. Could a parrot understand the concept of over and under separate from the relationship to its own body? For example, if it learned to tell you that the key is above the cork with respect to the midline of its head, what would happen if you then moved both objects above its head? Could it still understand "over" and "under" for two items when they aren't correlated to its own body as the frame of reference? We also want to pursue numbers further. At present, Alex can identify quantities up to 6, but is it real counting? Would he succeed on a task in which you gave him two lines of objects - with the same numbers of items - but then crunch one together, to make it shorter? If you ask children, they come to understand that the numbers are the same in the two lines, but earlier in development they confuse length with number. How will parrots respond?
We will do more studies with recursion. A paper in Science published in October 2002 stated only humans produce recursive phrases - that recursion is thus what separates human language from animal communication systems. But parrots, dolphins and sea lions respond to recursive sentences. Dolphins and sea lions differentially respond to statements such as "Touch the surfboard that is grey and to the left" versus "Swim over the Frisbee that is black and to your right." Alex responds to questions such as "What object is green and 3-corner?" versus "What colour is wood and 4-corner?" or "What shape is paper and purple?"
Some scientists say that animals' responses involve comprehension rather than production, and therefore don't count. But comprehension is often used as evidence of concept, particularly in young children who aren't yet verbal. Rather than argue, we are trying to train Alex to produce long phrases in response to questions like "Where's the key?" or "Where's the nut?" - to have him answer us "It's in the blue cup that's on the tray," or "It's in the yellow box on the chair." Those are tasks on which we are eager to begin. Such research touches on consciousness and what defines human language; how does one reconcile arguments for the uniqueness of humans with evidence for lower-level building blocks of these phenomena in other creatures?
I never claim that Alex has full-blown language; I never would. I'm not going to be able to put Alex on a stand and have you interview him the way you interview me. But Alex has basic building blocks that are language-like behaviours - and also elements of phenomena like consciousness and awareness. Is Alex conscious? Personally, I believe so. Can I prove it? No. Does he have perceptual awareness? That I can prove.
We hide things in various ways under cups; Alex and Griffin show that they know that the objects are still there, meaning that they understand that "out of sight" does not mean the object ceases to exist. We play the equivalent of shell games with our birds (like games at carnivals, where you hide an object under one of 3 cups and then switch the cups around) and both birds still find the hidden item. We did one study in which the procedure requires the experimenter to deceive the subject. We made believe that we were putting the object under one cup but sneaked it under another other or replaced it with a less desirable item. Alex went over to where he expected the item to be, picked up the cup, and found that the nut was not there; he started banging his beak on the table and throwing the cups around. Such behaviour shows that Alex knew the object was supposed to be there and that it wasn't. He gave very clear evidence that he perceived something, and that his awareness and expectations were violated. Griffin responded the same way.
There are some things that the birds do that, colloquially speaking, "just blow us away." We were training Alex to sound out phonemes, not because we wanted him to read as humans do, but we wanted to see if he understood that his labels are made up of sounds that can be combined in different ways to make new words. He now babbles, producing strings like "green, cheen, bean, keen", so we have evidence, but we needed more solid data.
Thus we tried to get him to sound out refrigerator letters, the same way one would train children on phonics. We were doing demos at the Media Lab for our corporate sponsors; we had a very small amount of time scheduled and the visitors wanted to see Alex work. So we put a number of differently coloured letters on the tray that we use, put the tray in front of Alex, and asked, "Alex, what sound is blue?" He answered, "Ssss." It was an "s", so we said "Good birdie" and he replied, "Want a nut." I didn't want him sitting there using our limited amount of time to eat a nut, so I told him to wait, and asked, "What sound is green?" Alex answered, "Ssshh." He was right, it was "sh," and we went through the routine again: "Good parrot." "Want a nut." "Alex, wait. What sound is orange?" "Ch." "Good bird!" "Want a nut." We went on and on and Alex clearly got more and more frustrated. He finally got very slitty-eyed and looked at me and stated, "Want a nut. Nnn, uh, tuh."
Not only could you imagine him thinking, "Hey, stupid, do I have to spell it for you?" but the point was, he had leaped over where we were had begun sounding out the letters of the words for us. This was in a sense his way of saying to us, "I know where you're headed! Let's get on with it," which gave us the feeling that we were on the right track with what we were doing. These kinds of things don't happen in the lab on a daily basis, but when they do, they make you realise there's a lot more going on inside these little walnut-sized brains than you might at first imagine.