Eat five pieces of fruit and vegetable daily. Limit your consumption of meat; eat wild grains and fish, reduce salt and sugar. Exercise regularly. Talk a lot and tell stories; don’t work too hard; get plenty of sleep, and share and share alike1.
Humans have been using their brains to think, and their stomachs to digest food, since the beginning of human times; both processes appear so normal that we take them for granted. However, in the past fifty years medical scientists have discovered so much about the human digestive system, and the significance of different kinds of food, that we have a better “user guide” that enables us to use our bodies more effectively and as healthy beings we are living far longer. Discoveries about the brain might soon give us a better “user guide” to our thought processes — that would be a prize well worth the search.
It was the work done by archaeologists at the Sterkfontein Caves outside Johannesburg that helped to identify empathy and language as key components in intellectual development2. Talking alone can’t explain the amazing outburst of creativity that has shaped, and then reshaped the human experience during the last 100,000 years. In a remarkable proposition put forward in 2001 “The Madness of Adam and Eve”, David Horrobin3 suggests that this could have been stimulated by a slight mutation in the nature of the fats that comprise the myelin sheathing in the brain, possibly caused when our distant ancestors found ways of adding significant amounts of fish to their diets. Extensive research has shown that about 1.5% of every population anywhere in the world has the appropriate combination of genes to create a predisposition for schizophrenia, though only half of these actually become schizophrenic. Schizophrenia is a devastating condition that brings much misery to the sufferers; their brains just don’t seem to work consistently; and easily deteriorate into total chaos and illogicality.
Horrobin suggests that schizophrenia is a disease that randomly destroys sections of myelin sheathing so that the brain simply “leaks”, thus making endless false connections. His fascinating proposition is this; amongst the first and second level relatives of schizophrenics are some of the most creative people in the world, people like Beethoven, Einstein, Darwin, Handel, Coleridge, Tchaikovsky, Leonardo de Vinci, Hans Christian Anderson and Winston Churchill. Perhaps, postulated Horrobin, schizophrenia is the yeast within the dough of modern humanity which, in small quantities, liberates amazing creativity, but if too concentrated destroys a person. Very few of us, for example, could have discovered penicillin, or plasma-screen technology, but many of us ordinary mortals have been able to incorporate this into our thinking. Human progress is dependent not simply on geniuses alone, but on people with lesser intellects able to see the application of novel propositions.
Could this be put to the test? In 1989 Professor Bryan Sykes of Oxford4 developed a technology for extracting mitochondria DNA out of very old bones, so revealing an exact history of that individual’s evolutionary past on the female side. Sykes’ work attracted great interest when he extracted such DNA from a 9,000 year old skeleton found in Cheddar Gorge. Comparing the mitochondria DNA of that skeleton with samples taken from local people he found that three of those currently living in the village of Cheddar (two school children and the local history teacher) were almost direct descendents on the female side of that long-dead man. This was a stunning result with enormous implications for both the scientists and historians.
So, might Horrobin’s proposition be used to explore the origins of schizophrenia? For more than 100 years archaeologists have known that another species of human, Neanderthal Man5, coexisted with ourselves until suddenly disappearing about 30,000 years ago. Neanderthals were very similar to us; they were a big, heavy-boned species, with large brains, but they don’t seem to have been that bright — they had no complex technology, no art, and no form of religious behaviour. Maybe they were just like us but, and here is the fascinating proposition, without the benefit of schizophrenia maybe they had no imagination, no ability to think outside the immediate present. They have been dead so long, is it possible to ever know?
So far none of the genetic studies instigated by Sykes and others have found any trace in existing humans of random DNA that might have come from any Neanderthal ancestors. If our distant ancestors did mate with such neighbours their offspring were probably sterile, like asses. Which poses a fascinating question. Suppose it were possible to extract Neanderthal DNA from bones three or four times older than those found in Cheddar, might this tell us far more about why modern man is as he is, than ever we could find out by comparing our DNA with that of the chimpanzees or the bongos? Such an experiment seems about to happen. Scientists at the Max Planck Institute in Leipzig6 are confident that they are close to developing the technology to extract such “uncontaminated” Neanderthal DNA, and then over a two or three-year period they might be able to reassemble the 3 billion building blocks of the Neanderthal genome. Then, by comparing our DNA with that of the Neanderthals, we might just be able to understand far more about what it is that gives our human brains their amazing “brightness”.
This is an unfolding story. Our “shadows” may be far more important than we realise7. It is similar genetic technologies that are helping to explain our species remarkable colonisation of the entire world, a story that continues in Thesis 90. Thesis 81: 27th August 2006