This conjecture is rubbish of course, but it entertains. We have not
begun to systematically optimize the human brain at all. Such
optimization may even try DNA adjustment in the future.
Where we have a serious weakness is that our education system is
multiply flawed let alone focused on the core objective of optimizing
any child's brain. That objective is not even recognized.
What happens instead is that the child makes choices that help or
hinder him for the balance of his life.
It is clear to me that all skills can be brought up to optimal levels
in everyone. Some may well take a lot longer but that is irrelevant.
Taking two years to perfect memory skills as compared to a standard
of six months is meaningless if it then allows you to complete a
history and law degree.
The other weakness in our education system is that low skill levels
make information gathering difficult. If you read all extant
material on a subject and clearly understand all read and then
discuss with others, odds are you will be on the top of your game and
your brain will produce surprises. None of this is going to happen
if your reading comprehension is flawed.
Brain development has two phases. Skill development to a high level
and application to polish those skills and acquire data.
Human intelligence
'peaked thousands of years ago and we've been on an intellectual and
emotional decline ever since'
STEVE CONNOR
MONDAY 12 NOVEMBER
2012
Is the human species
doomed to intellectual decline? Will our intelligence ebb away in
centuries to come leaving our descendants incapable of using the
technology their ancestors invented? In short: will Homo be left
without his sapiens?
This is the
controversial hypothesis of a leading geneticist who believes that
the immense capacity of the human brain to learn new tricks is under
attack from an array of genetic mutations that have accumulated since
people started living in cities a few thousand years ago.
Professor Gerald
Crabtree, who heads a genetics laboratory at Stanford University in
California, has put forward the iconoclastic idea that rather than
getting cleverer, human intelligence peaked several thousand years
ago and from then on there has been a slow decline in our
intellectual and emotional abilities.
Although we are now
surrounded by the technological and medical benefits of a scientific
revolution, these have masked an underlying decline in brain power
which is set to continue into the future leading to the ultimate
dumbing-down of the human species, Professor Crabtree said.
His argument is based
on the fact that for more than 99 per cent of human evolutionary
history, we have lived as hunter-gatherer communities surviving on
our wits, leading to big-brained humans. Since the invention of
agriculture and cities, however, natural selection on our intellect
has effective stopped and mutations have accumulated in the critical
“intelligence” genes.
“I would wager that
if an average citizen from Athens of 1000BC were to appear suddenly
among us, he or she would be among the brightest and most
intellectually alive of our colleagues and companions, with a good
memory, a broad range of ideas and a clear-sighted view of important
issues,” Professor Crabtree says in a provocative paper published
in the journal Trends in Genetics.
“Furthermore, I
would guess that he or she would be among the most emotionally stable
of our friends and colleagues. I would also make this wager for the
ancient inhabitants of Africa, Asia, India or the Americas, of
perhaps 2,000 to 6,000 years ago,” Professor Crabtree says.
“The basis for my
wager comes from new developments in genetics, anthropology, and
neurobiology that make a clear prediction that our intellectual and
emotional abilities are genetically surprisingly fragile,” he says.
A comparison of the
genomes of parents and children has revealed that on average there
are between 25 and 65 new mutations occurring in the DNA of each
generation. Professor Crabtree says that this analysis predicts about
5,000 new mutations in the past 120 generations, which covers a span
of about 3,000 years.
Some of these
mutations, he suggests, will occur within the 2,000 to 5,000 genes
that are involved in human intellectual ability, for instance by
building and mapping the billions of nerve cells of the brain or
producing the dozens of chemical neurotransmitters that control the
junctions between these brain cells.
Life as a
hunter-gatherer was probably more intellectually demanding than
widely supposed, he says. “A hunter-gatherer who did not correctly
conceive a solution to providing food or shelter probably died, along
with his or her progeny, whereas a modern Wall Street executive that
made a similar conceptual mistake would receive a substantial bonus
and be a more attractive mate,” Professor Crabtree says.
However, other
scientists remain sceptical. “At first sight this is a classic case
of Arts Faculty science. Never mind the hypothesis, give me the data,
and there aren’t any,” said Professor Steve Jones, a geneticist
at University College London.
“I could just as
well argue that mutations have reduced our aggression, our depression
and our penis length but no journal would publish that. Why do they
publish this?” Professor Jones said.
“I am an advocate of
Gradgrind science – facts, facts and more facts; but we need ideas
too, and this is an ideas paper although I have no idea how the idea
could be tested,” he said.
THE DESCENT OF MAN
Hunter-gatherer man
The human brain and
its immense capacity for knowledge evolved during this long period of
prehistory when we battled against the elements
Athenian man
The invention of
agriculture less than 10,000 years ago and the subsequent rise of
cities such as Athens relaxed the intensive natural selection of our
“intelligence genes”.
Couch-potato man
As genetic mutations
increase over future generations, are we doomed to watching
soap-opera repeats without knowing how to use the TV remote control?
1 comment:
This is a brilliant theory. I see but two minor flaws. 1. There is no ...you know ... like evidence. Never mind actua evidence, there is not even any ...like evidence.
2. The theory makes no actual measurable predictions. That is, the theory is not falsifiable. Which means that it is not really a scientific theory. More a theory like intelligent design is a theory.
Other than that, it is great.
Post a Comment