Human Evolution Speeding Up, Study Says

Explosive population growth is driving human evolution to speed up around the world, according to a new study.

The pace of change accelerated about 40,000 years ago and then picked up even more with the advent of agriculture about 10,000 years ago, the study says.

The Genographic Project
And while humans are evolving quickly around the world, local cultural and environmental factors are shaping evolution differently on different continents.

"We're evolving away from each other. We're getting more and more different," said Henry Harpending, an anthropologist at the University of Utah in Salt Lake City who co-authored the study.

For example, in Europe natural selection has favored genes for pigmentation like light skin, blue eyes, and blond hair. Asians also have genes selected for light skin, but they are different from the European ones.

"Europeans and Asians are both bleached Africans, but the way they got bleached is different in the two areas," Harpending said.

He and colleagues report the finding this week in the journal Proceedings of the National Academy of Sciences.

Snips of DNA

The researchers analyzed the DNA from 270 people in the International HapMap Project, an effort to identify variation in human genes that cause disease and serve as targets for new medicines.

The study specifically looked for genetic variations called single nucleotide polymorphisms, or SNPs (pronounced "snips"), which are mutations at a single point on a chromosome.

"We look for parts of chromosomes that are common in the population but are new, and if they are common but recent, they must have gotten to high frequency by selection," Harpending explained.

"And the reason we know they are new or recent … is that they haven't had time to break and re-form," he added.

Over time, chromosomes randomly break and recombine to create new sequences of SNPs along the chromosome. A large number of identical SNPs means the mutation is advantageous and new.

The Genographic Project
The researchers' analysis found that 7 percent of human genes have been undergoing rapid, recent evolution.

If humans had always evolved at this rate, the difference between modern humans and chimps should be 160 times greater than it really is.

"We realized we must be in a transient [phase], that evolution hasn't been going this fast for long in our species," Harpending said. "And so we wondered why."

According to Charles Darwin's famous theory, evolution happens faster in big populations.

Harpending said the timing of the newly observed evolution acceleration coincides with explosive growth in human population, coupled with humans living in new environments and changing cultures.

The biggest changes have come since the end of the last ice age, about 10,000 years ago, which opened up new environments for the quickly expanding human population to grow from millions to billions.

More people mean more mutations, Harpending noted.

"You are also giving them the potential to be adaptive mutations," said Brian Verrelli, who studies population genetics and evolution at Arizona State University in Tempe and was not involved in the research.

Regional Differences

Verrelli said the new study is interesting and accurately explains the accelerated evolution with a plausible model based on demographics.

Importantly, he said, the research indicates that any speed-up in evolution "had to have happened differently in different geographic regions."

While Harpending and colleagues have yet to connect all the different evolving genes with specific traits, they have linked a few.

For example, Europeans as recently as 8,000 years ago developed lactose tolerance, which allows adults to drink fresh milk—a staple of the agricultural economy.

Genes that suppress body odor and dry ear wax are spreading rapidly in Asia. In Africa, a speed-up is found in genes that thwart malaria.

Many of the evolving genes appear related to changes in diet that accompanied the widespread adoption of agriculture, Harpending noted.

For example, Europeans can easily digest cereal grains (CRACKERS), but Kalahari bushmen in Africa, Australian Aborigines, and Native Americans often become diabetic when eating a high-carbohydrate diet.

"We can see the genes changing. We are evolving to cope with these new cereals," Harpending said.

Eventually, this rapid pace of genetic evolution should slow, assuming the human environment and diet stabilize, Harpending said.

However, infectious diseases evolve more quickly in large, sedentary populations, which may keep the adaptation cycle ramped up for the foreseeable future.

"It's going to take a while to stabilize," he said. "By 'a while,' I'm talking tens of thousands of years."

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bottom line. When do I get my super powers?

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Why would you write off the article when clearly there are truths to it.

-whites and asians evolving in response to colder climates with less sun
-asians less stinky (appocrine glands are either very low in asians or non-existent)

Ever bang asians?

Probably not since ur starting to sound like a product of close relatives producing an offspring. No wonder ur quick to claim that the gene pool is degrading.

The article doesn't address disorders, so that doesn't mean that such events don't occur.

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and the "other side" don't?

Somewhere a villiage is missing it's idiot....

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Owned!

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I'm a jerk.

Rubbish.... yet another bias and blind post by Mark.

Fucking inbreed.

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cracks me up how you refer to anyone remotely related to gene or evolution research as "darwinists", though the inaccuracy of said moniker has been explained to you ad nauseum.

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your sig was 1.8mb

Posts about genetics being rebuked by mark with double and triple posts..Batman battling all the while..mark being full of well-phrased bullshit...ahhh things are back to normal. The world is balanced


lol.

So why do you not believe that evolution could have occurred? Why couldn't it have been God's tool for creating the species on this planet?

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SOmething I learned in my Anthropology class:Regional Continuity Model proposes that local populations in Eruope, Asia and Africa continued their indigenous evolutionary development from archaic Homo Sapiens to anatomically modern humans by gene flow and are not a separate species. Evidence include that in China, certain dental and cranial traits show long histories of evolutionary occurrence in that area.
In particular, evidence for a broad and flat face is claimed to link fossil and modern inhabitants of the Far East. In the Indonesian/Australian region, a medley of cranial features has been used to aruge that modern Aborigines are descended from Javanese Homo erectus via Ngandong and Lake Mungo Australian type. Among the traits claimed to show evolutionary continuity in this part of the world are well-developed brow ridges a receding forehead and facial prognathism.
Problem with this theory is that anthropologists prefre a cladogenic (branching) speciation, not widespread phyletic change (Hiendergenesis). Experts also disagree on diagnostic usefulness of many traits to show regional continuity. Oldest modern fossil are from Africa, whereas modern humans appear much later elsewhere and finally there is a growing molecular evidence for our speices cladogenic evolution in Africa or Middle East. mtDNA collected from a Neanderthal specimen suggest that these people belong to a distinct and dead-end species that made little, if any contribution to modern human's gene pool.

Complete Replacement or "Out of Africa" proposes that anatomically modern populations arose in African within the last 200,000 years and then migrated replacing populations in Europe and Asia. Considers that little to no inbreeding occurred.
Evidence-genetic data (mtdNA) obtained from living people. By far the oldest skeletal material comes from Africa (Klasies River Mouth, Border Cave, Qafsezeh)
Problems-The methodology of moelcular scientists has been faulted. Using the same mt DNA material other scientists constructed differ from other groups without African roots (displays that Homo Sapiens arose in Asia, not Africa)

Partial Replacemnt proposes that anatomically modern Homo sapiens first evolved in African from Archaic Homo Sapiens over 100,000 years ago. Moving into Eurasia, modern humans hybridized, porbably to a limited degree, with resident archaic groups including Neanderthal and eventually replaced them. Gradual influence by environmental conditions.

Evidence of hybrid forms from Europe such as Lagar Velho 1 from Portugal.
Problems-not even data available.

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You make me laugh, marky

Darwinism, for the zillionth time, specifically refers to the theory of biological evolution developed by Charles Darwin. Guess what? Understanding of evolution has advanced and changed in the 150 years since. Calling those who believe in evolution "darwinists" is like referring to everyone involved in psychiatry as "freudists". The fact that you're incapable of making the distinction seriously undermines the remaining shreds of your credibility.

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your sig was 1.8mb

AHAHAHAHAHAHAHAHAHAHHAHAHAHAHAHAHAHAHAHHAHAHAHAHAH AHAHAHAHAHAHAHHAHAHAHAHAHAHAHAHAHAHAH!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! eleven

Really. It's like calling you a Jew. After all, the "foundational concept" of your religion remains unchanged, right? [/]

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your sig was 1.8mb

Mark thinks more like a woman than most of the guys on here do.

Why? Can't except logic and will ramble on and on to make her point that's been beaten to death.....

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