Transcript

Commentary

The study of the human brain has been a popular area of research as we have sought to understand its inner workings. One approach has been to look at how our brains have evolved and what aspects are held in common with other animals.

Here in Japan one of the longest running animal studies is happening at Kyoto University.

Professor Tetsuro Matsuzawa heads up the Primate Research Institute, one of the most respected laboratory studies into chimpanzees in the world.

Professor Tetsuro Matsuzawa

Oh, look at that. Amazing.

Commentary

Known as the Ai Project, it was named after the first chimpanzee to arrive there forty-three years ago.

Professor Tetsuro Matsuzawa

I clearly remember when I was twenty-six, as Assistant Professor of this Institute, I met the chimpanzee named Ai. I was fascinated to see chimpanzees in everyday life.

Up to that point I had no idea about chimpanzees, and I thought it must be a big black monkeys. But it’s not a big black monkey, it’s really something so like us. From the beginning I recognised the great similarity between the chimpanzee and me.

That is called pant-hoot - greeting voice. He say hello I’m here. You called me and I’m here and she called I’m here too.

To know the chimpanzees you can know about humans because we share the common ancestor only six million years ago. So, if you want to know, you yourself, in comparison to the other creatures, the most important one is the evolutionary neighbour. That means chimpanzees.

Commentary

Matsuzawa believes that the only way to understand more about the chimpanzee mind and life as a whole is to study them both in captivity and in the wild. In Guinea, West Africa, he’s running a series of field studies on wild chimpanzees, while here in Kyoto he’s able to run controlled experiments in a laboratory setting.

Professor Tetsuro Matsuzawa

Here we have a group of fourteen chimpanzees of three generations. Chimpanzees are group living, isolated single chimpanzee is no more chimpanzee, so all chimpanzees should be put together. They are living in a group in their natural habitat, so do they in captivity. And I provided a small forest for them. So this is a forest. Fifteen metres high climbing frames – hi Chloe – and a lot of vegetation. Trees and shrubs. I’m not teaching human language to the chimpanzees. I really want to communicate with them in their way of communication. In this community not only chimps but also humans co-exist together and definitely they know that I’m the top-ranking male.

Commentary

Matsuzawa’s knowledge of chimpanzee culture and traditions underpin his field studies in Guinea. Here, he is leading the way on researching how chimpanzees learn to use tools, such as leaves to drink water, twigs to tease out termites and rocks to crack nuts.

Professor Tetsuro Matsuzawa

I really want to know the chimpanzee way of passing the knowledge, techniques, values, to the next generation.

So here is a chimpanzee, three and a half years old. Not yet acquired the skill. Then the girl went to an adult chimpanzee who is cracking open nuts and carefully watching the skill in this close distance. This is their way of observation. Now the girl went back to her original place to try to crack open nuts. Still very difficult. So it’s very clear she’s not motivated to eat the kernel. She’s really motivated to make the copy of the adult behaviour. So they do not teach - they show the good model.

Commentary

Until recent years, tool use had been considered uniquely human. The discovery of tool use in chimpanzees in the wild is not only an insight into chimpanzee culture and learning processes, but tells about how tool use may have developed in early humans.

In his laboratory work, Matsuzawa was again interested in finding out how chimpanzees learn. He wanted to explore photographic memory and so invented a series of experiments using numerical sequences. Part of the task involved his chimpanzees memorising at a glance the numerals presented on a computer screen. Matsuzawa uses a technique of ‘participation observation’ in his studies. Every day there is a ritual of inviting the chimpanzees to take part in tasks. This means it’s a voluntary participation.

Today he’s working with Ai and her ten-year old son Ayumu.

Professor Tetsuro Matsuzawa

So every day in the first session we confirm their knowledge about the numerical sequence, 1 through 9. Both Ai, chimpanzee and Ayuma, chimpanzee. The mother and the child. So now already more than 9, 10, 11, up to 12, is tested in this session and in the next session we will test up to 19. This sound we call ‘chime’ and when he makes a correct response – chime. The most important point is the feedback – whether it is correct or incorrect, by the sound – but the correct trial is accompanied by a small treat.

Commentary

The treat is part of the food rations the chimpanzees receive every day. Chopped apples and raisins are released automatically by the computer programme, in return for a correct response.

The chimpanzees signal when they have finished the session.

Professor Tetsuro Matsuzawa

The knocking means the request. ‘Please in a hurry to prepare the next session. I’m ready to go.’

Commentary

They are now ready for the masking experiment.

Professor Tetsuro Matsuzawa

So the task is ‘give me the question’ and it’s so quick. Seven numerals touch one then the other numerals are gone. Still he can remember what numerals appeared in which position, so this is a real performance. So Ayuma, chimpanzee, can remember the seven numerals at a glance. Young chimpanzee is better than other chimpanzee in general, so that is in the case too in Ai and Ayumu. Ayumu, the son, is better than the mother. The phenomenon itself is very close to our cases, human cases. The younger generation is good at learning new things than the older persons.

Commentary

At the end of each session there is a period of play and grooming. This is important for both bonding and reinforcing status.

Ai may be playing with children’s toys, but no child could match her or her son’s memory skills. Human participants also take part in the study – attempting the same task and using the same equipment. Now the session is over, Matsuzawa’s students, Lyla and Akiho, decide to have a go themselves.

Lyla

I can’t memorise the order and position of the numerals. It’s very difficult.

Akiho

If I pass 5 then it’s getting difficult I think – 3, 4. 5 – I don’t know the next one. My score was 20 per cent.

Lyla

And my score was only 10 per cent.

Akiho

But Ayuma, the young chimpanzee’s, score was over 50 per cent.

Professor Tetsuro Matsuzawa

Let’s try to challenge Ayumu, the chimpanzee. OK, let me try again. Nope, let me concentrate. Wow, difficult. Whoops. Oops. Embarrassing. So I completely failed, but this is Ayumu’s performance – 1,2,3,4,5,6,7,8,9. So this clearly tells us that there is a cognitive task – memorising numerals at a glance – in which young chimpanzees are better than human adults.

We know one among thousands human children has this kind of capability, but all of the three young chimpanzees, showed this kind of photographic memory. So it’s a clear difference. Chimpanzees are good at memorising things at a glance.

So what’s the meaning of this finding? Human has a linguistic capability that is really uniquely human. Human speech, human language. What is the advantage of human speech, human language? That is very clear that the information is portable.

Suppose that you see a creature passing in front of you, there was a white spot on the forehead and brown hairs and black hairs on the legs, this kind of immediate memory may be important for next encounter. But, suppose that you can summarise your direct experience to say “horse, wild horse”. You can bring back your experience to your community to say ‘I saw the horse in that place. Let’s go together to hunt. It’s a big meat.’ So this kind of thing is the clear advantage of having the language, having the symbol in comparison to the direct memory. So chimpanzees lives in the world of the here and now, so that very good at capturing the world in front of them. That is proved by photographic memory of chimpanzee.

So I have my own evolutionary scenario, this kind of things. So the common ancestor six million years ago may have had this kind of photographic memory and it’s still kept in chimpanzee lineage. But human lineage, we lost. We got the symbolic representation, we got speech and language.

Commentary

Matsuzawa’s work shows that in the course of cognitive development humans have acquired linguistic skills, but he maintains this has been at the expense of losing their photographic memory.

Professor Tetsuro Matsuzawa

It’s my great pleasure to be here to talk about my study on the chimpanzee mind.

Commentary

Matsuzawa has published his findings widely and disseminated them on the world stage at conferences, but he has found that for some people the idea that chimpanzees can outperform humans is difficult to accept.

Professor Tetsuro Matsuzawa

It’s so interesting to see the response by the ordinary people about this thing. And I’m so surprised to see that it’s very difficult for some people to accept the truth.

Some says, ‘Oh, it’s operant conditioning of food reward.’ Or, ‘intensive training is necessary.’ Or, ‘it must be a genius chimpanzee.’ So, anyway, the point is, people are not so happy to see the truth that chimpanzees can be better than us.

It might be a single case, but in which chimpanzee can outperform humans. So therefore, we cannot say that humans are always superior to the other creatures.