Category Archives: evolutionary psychiatry

A Talk About The Evolution of Mind

Psychologist Professor Thomas Suddendorf gives a fascinating talk on the evolution of mind  with reference to comparative primatology. Understanding other primates gives us profound insights into the human mind and brain. Professor Suddendorf also gives us a warning about how our own activities are endangering the lives of our nearest living relatives.

An index of the site can be found here. The page contains links to all of the articles in the blog in chronological order. 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 justinmarley17@yahoo.co.uk. 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.

Does This Bonobo Have A Theory of Mind?

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 justinmarley17@yahoo.co.uk. 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.

The Ancient Human-Like Species with Frontal Brain Enlargement (AKA Brodmann Area 10)

Round Moni, lake in the volcanic craters of Kelimutu, Author: SerenadeGNU Free Documentation License

Modern humans (Homo Sapiens Sapiens) are not the only intelligent hominids to have existed in recent history. If we go back 30,000 years ago there were several other intelligent hominids that dominated their territories. Our ancestors had to work out how to coexist with these species. In the long run only our species survived. Thinking of these other hominids as distinct species is controversial in one special case – the so called ‘Hobbit Man’ of the Indonesian island of Flores also known as Homo Floresiensis.

The controversy centres on whether Homo Floresiensis were indeed a separate species or instead were humans with dwarfism. The debate was intense after their initial discovery although it has declined somewhat and the evidence is more in favour of them being a distinct species. The recovered specimens date back 18,000 years ago. Unfortunately early attempts at recovering DNA from the specimens were unsuccessful and the de facto gold standard of species identification through genome analysis is awaited.

Homo floresiensis, Ryan Somma , Creative Commons Attribution-Share Alike 2.0 Generic License (CC BY-SA 2.0)

However comparative anatomy helps to settle some of the questions. The authors of this Science paper produced a virtual endocast. In other words they used markings on the skull and other measurements to estimate the shape of the brain. They compared this brain to that of other species including modern humans with and without dwarfism. The researchers found that the brain shape was very different to that of modern humans. However it did fit relatively closely with that of a very distant ancestor of humans – Homo Erectus. The researchers went as far as to suggest that Homo Floresiensis and Homo Erectus shared a not too distant ancestor.

H.Floresiensis would have faced Giant Storks which towered at just under six feet compared to the 3 foot 6 height estimate for one of the recovered specimens (of a similar height to the other specimen). H.Floresiensis faced other challenges. To get to the Island of Flores it has been suggested that H.Flores was seafaring and the journey must have taken place during the initial migration. Other species in the region include Java Man (Homo Erectus) which lived around 1.8 million years ago.

The most interesting aspect of the above paper is that the researchers in this paper suggest that Brodmann Area 10 was relatively large when compared to scaled versions of the brains of other species.

Brodmann Area 10

In a previous post, I have argued that strictly speaking it is incorrect to label the Brodmann Areas on the basis of surface markings and instead Brodmann meant for them to be understood on the basis of the microscopic properties of the brain (cytoarchitecture). There is a more significant case for this in archaic species where we have little understanding of their neuroanatomy. Still we have to start somewhere. In another post I have written about the research findings in Brodmann Area 10 in humans. Thus research suggests a role for Brodmann Area 10 in memory (episodic memory and the recognition stage in spatial memory tasks) in humans as well as more complex motor activities and goal formation. There are alterations in the neurochemistry of BA10 in Schizophrenia whilst other research shows an increase in the cortical thickness in BA10 in people with Down Syndrome. Yet other studies show an increased activity in BA10 in risk-taking activities.

Clearly BA10 is a complex area with many possible functions including higher cognitive processes. Maybe H.Flores can tell us something about the brain changes that our distant intelligent ancestor H.Erectus evolved to make our species so successful in adapting to the environment.

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 justinmarley17@yahoo.co.uk. 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.