When I was a child, living in Poland, we believed that on Christmas Eve animals can speak human language. I waited till the magical time – midnight, and listened, but our dogs and cats did not take the opportunity to tell us what was on their mind. This tradition could have originated from the belief that the spirits of our ancestors could speak through the animals, or perhaps it referred to the presence of animals at the birth of Jesus. Either way, some scientists think that other species of animals have more in common with us than we think.
You might not be surprised to hear that dolphins have the skill of metacognition, that is the ability to think about, or oversee, their own thinking (Smith et al., 1995). In humans metacognition is related to self-reflection and self-awareness (Smith et al., 2012) . An example of this ‘thinking about thinking’ is the ‘tip-of-the-tong’ experience (when you are sure that you know something but cannot quite bring it to mind).
Researchers presented dolphins with sounds of different pitch, asking the animals to indicate the pitch of a given sound by touching response paddles (Smith et al., 1995). They increased the difficulty of the task by making some sounds very similar, therefore confusing the dolphins. In recognition that some sounds would be hard to differentiate, the dolphins were given the option to press a paddle indicating that they were ‘uncertain’ of the pitch of the sound. The ability to decline completion of a task due to uncertainty is an important aspect of metacognition. In humans the answer ‘I don’t know’ is thought to be based on the internal reflection: how likely is it that I will respond correctly? The less certain we are of our response, the more we hesitate. The dolphins in the experiment did indeed use the option ‘uncertain’ to decline completing the task when they thought it was too difficult. Moreover, this uncertainty was reflected in their behaviour: when sure of the response, dolphins swam towards the paddles so fast that the splash sometimes damaged the experimenters equipment. On the other hand, when they did not know the answer, they slowed, wavered and hesitated.
Other animals also showed the ability to monitor their own thinking. Similar to results seen in dolphins, macaques also show signs of metacognition. Specifically, when asked to decide whether the number of dots on the computer screen was smaller or greater than a value that they had learned before (Beran et al., 2006), macaques showed signs of hesitation and uncertainty when the task was hard. Other researchers asked the monkeys to match currently presented images to previous samples (Hampton, 2001). The more time elapsed between the pictures, the more ‘uncertain’ responses the animals gave. This was interpreted as an example of meta-memory – the ability to monitor our memories and decide whether they are clear enough to give a correct answer.
Does this mean that at least some animals, such as monkeys and dolphins, have consciousness? That depends on the definition of consciousness. Is hesitating and worrying about own performance enough? Do we need more sophisticated tests? Perhaps some of us (especially those living with pets) need no tests at all to feel that we have a lot in common with non-human animals and that we share our existence with them.
Post by Jadwiga Nazimek