Evolution of the Human Brain

Chiltern Humanist Meeting

Evolution of the Human Brain

The first of our autumn series of meetings will be held on Tuesday 10 September at Wendover Library.

Chris Reynolds, a retired scientist who has been a member of our group for several years, will take a new look at the evolution of the human brain. This has been researched at a biological level and raises the question of whether there is an inbuilt reason why some people are drawn to religion whilst others are not.

By temperament Chris likes to stand back and get an overview, rather than getting stuck in a narrow specialist area. After taking a doctorate in Chemistry he started working with computers in 1965; he was soon involved in research, and developed a language called CODIL over the following years. As Reader in Computer Science at Brunel University, Uxbridge during the 1970’s, he became involved in a project, funded by the British Library, concerned with interactive publication, which in a very elementary way anticipated the World Wide Web. Later he edited an online professional book review service on the subject of Human-Computer Interaction. In retirement his main interests are genealogy and local history.

His talk promises to be an interesting and different take on evolution.

Humans like to think they are something special - If not actually made by God in his own image, or the centre of the universe, are least we can console ourselves that we are more intelligent than the other animals that inhabit  our planet.

Or can we? No animal needs a brain that is bigger than necessary to survive, and we only have to look at the other mammals that share this planet to see that there are many cases where a species can be characterized by a greatly enlarged organ, whether it is a giraffe with its long neck, an elephant with its greatly extended nose, or the hands of the bat. And what about the changes we see in the whales!

This talk assumes that all mammals have brains that use the same neural code, and that the human brain is no more than a normal animal brain which has been supercharged to give it more processing capacity. It considers the limitations one might expect from a very simple neural code, and asks what the evolutionary pressures would be on the braians of hominids who were faced with the drying out of the African rain forests three million years ago.

The key factor would seem to be the point where cultural knowledge passed between the generations became more important to survival than the basic brain mechanisms on their own. At this point it there was an advantage in have a larger brain and developing faster mechanisms for learning. Better learning means better tools for survival, and one of those tools is language, which will automatically develop from generation to generation. One could get an auto-catalytic situation where the culture we pass on is augmented at a growing rate in each successive generation. 

Unfortunately the basic animal neural code is mathematically not very sophisticated, and while this is not important to other animals the defects become more evident as the human species pushes the code to its limits. While many of the defects can be avoided using language the logical weaknesses, such as confirmation bias, can, and are, exploited by religions and political belief systems. Even scientists will not be immune, as they take part in the rat race for prestige and funds!

After the talk I will be posting the slides used and background notes on this blog..