Is pampered humanity getting steadily less intelligent? Since modern humans emerged from the evolutionary brambles of our ancient ancestry, our bodies and minds have been transforming under the pressures of natural and sexual selection.
But what of human intelligence? Has our cognitive ability risen steadily since our forebears knapped the first stone tools? Or are our smartest days behind us? Gerald Crabtree, a geneticist at Stanford University in California, bets on the latter. He believes that if an average Greek from 1,000 BC were transported to modern times, he or she would be one of the brightest among us.
In two articles published in the journal Trends in Genetics, the scientist lays out what might be called a speculative theory of human intelligence. At the heart of Crabtree's thinking is a simple idea. The scientist draws on recent studies to estimate a figure for the number of genes that play a role in human intellectual ability, and the number of new mutations that harm those genes each generation. Theory says humans losing intelligence - Technology & science - Science - LiveScience. Humans may be gradually losing intelligence, according to a new study.
The study, published Monday in the journal Trends in Genetics, argues that humans lost the evolutionary pressure to be smart once we started living in dense agricultural settlements several thousand years ago. "The development of our intellectual abilities and the optimization of thousands of intelligence genes probably occurred in relatively non-verbal, dispersed groups of peoples (living) before our ancestors emerged from Africa," said study author Gerald Crabtree, a researcher at Stanford University, in a statement. Since then it's all been downhill, Crabtree contends. The theory isn't without critics, with one scientist contacted by LiveScience suggesting that rather than losing our smarts, humans have just diversified them with various types of intelligence today.
Human Intelligence Declining, Controversial New Study Suggests. By: Tia Ghose, LiveScience Staff Writer Published: 11/12/2012 12:34 PM EST on LiveScience Humans may be gradually losing intelligence, according to a new study.
The study, published today (Nov. 12) in the journal Trends in Genetics, argues that humans lost the evolutionary pressure to be smart once we started living in dense agricultural settlements several thousand years ago. Ntroversial study suggests human intelligence peaked several thousand years ago and we've been on an intellectual and emotional decline ever since - Science - News. 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. “Furthermore, I would guess that he or she would be among the most emotionally stable of our friends and colleagues. Athenian man. Mutations in the human brain are making us stupider, new research shows. Stanford.edu Gerald Crabtree, lead author of the study published in the journal Trends in Genetics, claims the brain drain has been going on for centuries.
Specific Genes Linked to Big Brains and Intelligence. Brain size and smarts are, to some extent, genetic — and now, a team of more than 200 researchers has uncovered specific genes that are linked to both brain volume and IQ.
Though scientists have suggested bigger brains are "smarter," this study is the strongest case yet for a genetic connection to brain size and to IQ. Of course, brain size is not 100 percent correlated with a person's intelligence, and other factors, including connections between brain cells and even a person's experiences, play roles. "We found fairly unequivocal proof supporting a genetic link to brain function and intelligence. For the first time, we have watertight evidence of how these genes affect the brain," said lead researcher Paul Thompson, a neurologist at the University of California, Los Angeles, School of Medicine. The international research team pooled brain scans and genetic data from around the world as part of a collaboration known as ENIGMA (Enhancing Neuro Imaging Genetics through Meta-Analysis).
Humans are slowly but surely losing intellectual and emotional abilities, article suggests. Human intelligence and behavior require optimal functioning of a large number of genes, which requires enormous evolutionary pressures to maintain.
A provocative hypothesis published in a recent set of Science and Society pieces published in the Cell Press journal Trends in Genetics suggests that we are losing our intellectual and emotional capabilities because the intricate web of genes endowing us with our brain power is particularly susceptible to mutations and that these mutations are not being selected against in our modern society. "The development of our intellectual abilities and the optimization of thousands of intelligence genes probably occurred in relatively non-verbal, dispersed groups of peoples before our ancestors emerged from Africa," says the papers' author, Dr. Gerald Crabtree, of Stanford University. From that point, it's likely that we began to slowly lose ground.
But not to worry. Human intellectual abilities in decline, claims geneticist. 13 November 2012 by Will Parker An intriguing new hypothesis published in the journal Trends in Genetics suggests that we are losing our intellectual and emotional capabilities because the intricate web of genes endowing us with our brain power is particularly susceptible to mutations and that these mutations are not being selected against in the modern world.
The papers' author, Dr. Is human intelligence declining? « The k2p blog. There is as yet no evidence, no hard data, no way of testing his speculation but Gerald Crabtree, a genetics Professor at Stanford University, believes that human evolution no longer selects for or favours intelligence.
Our intelligence may have peaked as hunter-gatherers. He has a point. The intricacies of modern, “civilised”, human society where “weak” members of society are cared for by others, are such that many genetic characteristics have effectively been decoupled from survival and reproduction. “Intelligence” as one such genetic charateristic is no longer something that affects survival or reproduction. In fact from the fertility rates around the world today it is already apparent that the greater the wealth (GDP) the lower the reproduction rate. Trends in Genetics - Our fragile intellect. Part I. Trends in Genetics - Our fragile intellect. Part II. Is Entire Human Race. Stanford University genetics professor Gerald Crabtree, thinks humans have been dumbing down for some time now.
He may be right, but not necessarily for the reasons he thinks. ...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......Life as a hunter-gatherer was probably more intellectually demanding than widely supposed, he says. Our Fragile Intellect -- PDF article by Gerald Crabtree discussing his theory From a newsrelease on the study: According to the 10,000 Year Explosion, civilisation actually accelerated human evolution in good ways. Crabtree Laboratory: Developmental Genetics, Chemical Biology, Signaling and Chromatin Regulation.