This conjecture is rubbish of course, but it entertains. We have notbegun to systematically optimize the human brain at all. Suchoptimization may even try DNA adjustment in the future.
Where we have a serious weakness is that our education system ismultiply flawed let alone focused on the core objective of optimizingany child's brain. That objective is not even recognized.
What happens instead is that the child makes choices that help orhinder him for the balance of his life.
It is clear to me that all skills can be brought up to optimal levelsin everyone. Some may well take a lot longer but that is irrelevant. Taking two years to perfect memory skills as compared to a standardof six months is meaningless if it then allows you to complete ahistory and law degree.
The other weakness in our education system is that low skill levelsmake information gathering difficult. If you read all extantmaterial on a subject and clearly understand all read and thendiscuss with others, odds are you will be on the top of your game andyour brain will produce surprises. None of this is going to happenif your reading comprehension is flawed.
Brain development has two phases. Skill development to a high leveland application to polish those skills and acquire data.
Human intelligence'peaked thousands of years ago and we've been on an intellectual andemotional decline ever since'
STEVE CONNOR
MONDAY 12 NOVEMBER2012
http://www.independent.co.uk/news/science/human-intelligence-peaked-thousands-of-years-ago-and-weve-been-on-an-intellectual-and-emotional-decline-ever-since-8307101.html
Is the human speciesdoomed to intellectual decline? Will our intelligence ebb away incenturies to come leaving our descendants incapable of using thetechnology their ancestors invented? In short: will Homo be leftwithout his sapiens?
This is thecontroversial hypothesis of a leading geneticist who believes thatthe immense capacity of the human brain to learn new tricks is underattack from an array of genetic mutations that have accumulated sincepeople started living in cities a few thousand years ago.
Professor GeraldCrabtree, who heads a genetics laboratory at Stanford University inCalifornia, has put forward the iconoclastic idea that rather thangetting cleverer, human intelligence peaked several thousand yearsago and from then on there has been a slow decline in ourintellectual and emotional abilities.
Although we are nowsurrounded by the technological and medical benefits of a scientificrevolution, these have masked an underlying decline in brain powerwhich is set to continue into the future leading to the ultimatedumbing-down of the human species, Professor Crabtree said.
His argument is basedon the fact that for more than 99 per cent of human evolutionaryhistory, we have lived as hunter-gatherer communities surviving onour wits, leading to big-brained humans. Since the invention ofagriculture and cities, however, natural selection on our intellecthas effective stopped and mutations have accumulated in the critical“intelligence” genes.
“I would wager thatif an average citizen from Athens of 1000BC were to appear suddenlyamong us, he or she would be among the brightest and mostintellectually alive of our colleagues and companions, with a goodmemory, a broad range of ideas and a clear-sighted view of importantissues,” Professor Crabtree says in a provocative paper publishedin the journal Trends in Genetics.
“Furthermore, Iwould guess that he or she would be among the most emotionally stableof our friends and colleagues. I would also make this wager for theancient inhabitants of Africa, Asia, India or the Americas, ofperhaps 2,000 to 6,000 years ago,” Professor Crabtree says.
“The basis for mywager comes from new developments in genetics, anthropology, andneurobiology that make a clear prediction that our intellectual andemotional abilities are genetically surprisingly fragile,” he says.
A comparison of thegenomes of parents and children has revealed that on average thereare between 25 and 65 new mutations occurring in the DNA of eachgeneration. Professor Crabtree says that this analysis predicts about5,000 new mutations in the past 120 generations, which covers a spanof about 3,000 years.
Some of thesemutations, he suggests, will occur within the 2,000 to 5,000 genesthat are involved in human intellectual ability, for instance bybuilding and mapping the billions of nerve cells of the brain orproducing the dozens of chemical neurotransmitters that control thejunctions between these brain cells.
Life as ahunter-gatherer was probably more intellectually demanding thanwidely supposed, he says. “A hunter-gatherer who did not correctlyconceive a solution to providing food or shelter probably died, alongwith his or her progeny, whereas a modern Wall Street executive thatmade a similar conceptual mistake would receive a substantial bonusand be a more attractive mate,” Professor Crabtree says.
However, otherscientists remain sceptical. “At first sight this is a classic caseof Arts Faculty science. Never mind the hypothesis, give me the data,and there aren’t any,” said Professor Steve Jones, a geneticistat University College London.
“I could just aswell argue that mutations have reduced our aggression, our depressionand our penis length but no journal would publish that. Why do theypublish this?” Professor Jones said.
“I am an advocate ofGradgrind science – facts, facts and more facts; but we need ideastoo, and this is an ideas paper although I have no idea how the ideacould be tested,” he said.
THE DESCENT OF MAN
Hunter-gatherer man
The human brain andits immense capacity for knowledge evolved during this long period ofprehistory when we battled against the elements
Athenian man
The invention ofagriculture less than 10,000 years ago and the subsequent rise ofcities such as Athens relaxed the intensive natural selection of our“intelligence genes”.
Couch-potato man
As genetic mutationsincrease over future generations, are we doomed to watching soap-opera repeats without knowing how to use the TV remote control?
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