“He who understands baboons would do more towards metaphysics than Locke” – Charles Darwin
The theory of mind is the ability to understand that you have a mental state as do others and that the mental state of others may differ from yours. The mental state may include beliefs, feelings and other attributes of our inner world. The theory of mind has been described as a special feature of humans but there is a lot of debate about other species. For instance Dolphins and Chimpanzees are notable examples of species that are suggested to have a theory of mind although the arguments are extended to many other species.
I took the video above at Twycross Zoo and thought it rather interesting for a particular segment at 0.16-0.31. During this sequence the senior maternal Bonobo makes a number of rapid non-verbal gestures towards the infant Bonobo. These consist of gazing upwards, accentuated blinking, indicating with the head and holding and pushing with the right arm. The maternal Bonobo seems to be indicating to the infant to turn around and look in a certain direction. The direction is indicated by the maternal Bonobos gaze and when the infant Bonobo does not look in this direction, the firm holding arm of the maternal Bonobo pushes the infant to face in that direction.
This at least is my interpretation. If it is correct then it implies that the maternal Bonobo recognises the infant is not looking in the right direction. This in turn implies an inference about the visual perception of the infant. The sceptic may disagree with my interpretation and I accept that it is limited to a behavioural observation.
However if it were correct there would be two interesting points about this
1. This demonstrates the use of several non-verbal means of communication in an apparently goal directed behaviour. These gestures may have been important for the development of a theory of mind which has been so central to the success of the human race.
2. Bonobos are our second closest relatives. They are also referred to as Pygmy Chimpanzees and have branched off from the lineage of Chimpanzees. Furthermore our lineage diverged from Chimpanzees around 6 million years ago. There are vastly different estimates for this figure which tend to be modified by new estimates of genetic mutation rates and genome sequencing data. What is rather unfortunate however is that every other species that has branched off from our lineage after Chimpanzees (i.e in the past roughly 6 million years) is now extinct. This means that from an evolutionary perspective Bonobos and Chimpanzees are our nearest surviving relatives and provide us with valuable insights into our history.
In the above quote from Darwin, i’m sure he might have been equally fascinated by Bonobos which were first described in 1928 and are classed as Greater Apes.
Index: There are indices for the TAWOP site here and here Twitter: You can follow ‘The Amazing World of Psychiatry’ Twitter by clicking on this link. Podcast: You can listen to this post on Odiogo by clicking on this link (there may be a small delay between publishing of the blog article and the availability of the podcast). It is available for a limited period. TAWOP Channel: You can follow the TAWOP Channel on YouTube by clicking on this link. Responses: If you have any comments, you can leave them below or alternatively e-mail firstname.lastname@example.org. Disclaimer: The comments made here represent the opinions of the author and do not represent the profession or any body/organisation. The comments made here are not meant as a source of medical advice and those seeking medical advice are advised to consult with their own doctor. The author is not responsible for the contents of any external sites that are linked to in this blog.