Navigation Links
Human Intellect Backsliding From Lack of Evolutionary Pressure: Study

FRIDAY, Nov. 16 (HealthDay News) -- The human race is slowly losing its intellectual and emotional capabilities because it no longer faces extreme evolutionary pressures, new research contends.

Human intelligence and behavior require optimal functioning of a large number of genes, but the intricate web of genes that gives people these capabilities has started to backslide, the scientists said in an article appearing Nov. 12 in the journal Trends in Genetics.

"The development of our intellectual abilities and the optimization of thousands of intelligence genes probably occurred in relatively nonverbal, dispersed groups of peoples before our ancestors emerged from Africa," study author Dr. Gerald Crabtree, of Stanford University, said in a journal news release.

In the early stages of human evolution, intelligence was critical for survival and there was immense selective pressure acting on the genes required for intellectual development. But once humans achieved a certain level of evolutionary progress, they slowly began to lose ground.

The development of agriculture led to urbanization, which may have weakened the power of natural selection to eliminate mutations that caused intellectual disabilities, the researchers explained.

Based on the frequency that harmful mutations appear in the human genome and the assumption that 2,000 to 5,000 genes are required for intellectual ability, Crabtree estimated the effect that the past 3,000 years (about 120 generations) of human history have had on humans. He concluded that all people now carry two or more mutations harmful to their intellectual or emotional stability.

He noted, however, that the loss of intellectual and emotional capabilities is quite slow and it's likely that a solution will be found in the future.

"I think we will know each of the millions of human mutations that can compromise our intellectual function and how each of these mutations interact with each other and other processes, as well as environmental influences," Crabtree said.

"At that time, we may be able to magically correct any mutation that has occurred in all cells of any organism at any developmental stage," he said. "Thus, the brutish process of natural selection will be unnecessary."

More information

The PBS show Nova asked experts to explain human intelligence.

-- Robert Preidt

SOURCE: Trends in Genetics, news release, Nov. 12, 2012

Copyright©2012 ScoutNews,LLC.
All rights reserved

Related medicine news :

1. Human umbilical cord blood cell co-culture supports embryonic stem cell expansion
2. Sociology, economics researchers receive grant to study development across the human lifespan
3. Gut Bacteria Often Similar in Humans, Chimps: Study
4. First trial in humans of minicells: A completely new way of delivering anti-cancer drugs
5. Testing pain killers on humans could save money and speed the arrival of new drugs
6. New, improved mouse model of human Alzheimers may enable drug discovery
7. Spread of human melanoma cells in mice correlates with clinical outcomes in patients
8. First gene therapy study in human salivary gland shows promise
9. Clinical trials for first-ever human hookworm vaccine advance
10. Bigger human genome pool uncovers rarer variants
11. A Viagra follow-up? Drug used to treat glaucoma actually grows human hair
Post Your Comments:
(Date:11/27/2015)... ... November 27, 2015 , ... The rapid speed at which ... age, more care is needed, especially with Alzheimer’s, dementia and other cognitive conditions ... overworked. The forgotten part of this equation: 80 percent of medical care occurs ...
(Date:11/27/2015)... (PRWEB) , ... November 27, 2015 , ... ... the November 27th edition of USA Today in Atlanta, Dallas, New York, Minneapolis, ... of 750,000. The digital component is distributed nationally, through a vast social media ...
(Date:11/27/2015)... ... November 27, 2015 , ... A simply groundbreaking television series, "Voices in ... that delves into an array of issues that are presently affecting Americans. Dedicated to ... dialogue, this show is changing the subjects consumers focus on, one episode at a ...
(Date:11/27/2015)... ... November 27, 2015 , ... Dr. Thomas Dunlap and ... and Dr. Tucker Bierbaum with Emergency Medicine at St., Joseph Health System’s Santa ... and Sepsis conditions present in similar ways and require time-critical intervention to avoid large ...
(Date:11/26/2015)... ... November 26, 2015 , ... CognisantMD and Cambridge ... imaging in the Waterloo region. Using the Ocean Platform, family physicians can now ... their electronic medical record (EMR) without the need for redundant patient entry or ...
Breaking Medicine News(10 mins):
(Date:11/26/2015)... Research and Markets ( ) has announced ... Outlook to 2019 - Rise in Cardiac Disorders and Growing ... to their offering. Boston ... scientific and others. --> The market ... Boston scientific and others. ...
(Date:11/26/2015)... 2015 ... the  "2016 Future Horizons and Growth ... Testing Market: Supplier Shares, Competitive Intelligence, ... --> ) has ... Future Horizons and Growth Strategies in ...
(Date:11/26/2015)... , November 26, 2015 ... the addition of the  "2016 Future ... European Therapeutic Drug Monitoring (TDM) Market: ... Intelligence, Emerging Opportunities"  report to their ... has announced the addition of the  ...
Breaking Medicine Technology: