New DNA findings show that human genetic mutations are more recent, more rapid than once thought.

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http://www.philly.com/inquirer/health_science/weekly/20100208_Evolution_on_the_march.html?viewAll=y


Evolution on the march


Conventional wisdom holds that if you could bring back someone from 40,000 years ago, he or she would blend perfectly well with today's population.
After all, the fossils show that our ancestors were "anatomically modern" by 100,000 years ago, and by 40,000 B.C., they were creating complex tools and art.

It was easy to assume our species hadn't evolved much since then.

Now molecular biology is overturning that assumption.

Evidence for more recent evolution is coming not from fossils but from patterns seen in the DNA of contemporary people. Genes show that blue eyes, for example, apparently didn't exist until 6,000 years ago, and the ability to digest milk goes back just 7,000 years.

Scientists have compared genes from different ethnic groups and found more recent genetic mutations are changing the way some people metabolize food, store fat, grow hair, and fight disease.

One new mutation that appears only in Asians may improve hearing and balance.

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Already, for example, some scientists have theorized that recent genetic changes have endowed Ashkenazi Jews with higher average intelligence.

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The scientists argue that none of this work points to the superiority of one group or person over another. It's an old misconception that evolution is elevating humanity up some ladder of perfection, he said, or that one group could be more evolved than another.

"When we talk about natural selection, people think about survival-of-the fittest," Akey said, "but that's not really how it works."

Local environments bend the course of evolution. Traits that would make someone "fit" in one place could prove to be liabilities in another.

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Evolution through domestication can happen in just a few centuries, said Washington's Akey, who also studies genetics of domestic dogs. He's comparing breeds to see where the DNA is separating the Great Danes from the dachshunds, the border collies from the poodles.

Oddly, he said, he has found a parallel - at the DNA level, dogs and humans are showing some of the same changes. It's possible, he said, that both dogs and humans needed to acquire new disease-resistance genes in response to crowding. Or it could be a reflection of the taming and domestication of both species.

Dog brains are smaller than those of their ancestors, the wolves, and likewise our brains are apparently smaller than those of our ancestors 20,000 years ago, Harpending said. The human brain hit its peak and then began shrinking.

It may mean our ancestors needed more brainpower to survive in the wild, or it could be that our brains have become better organized and more compact - just as computers have done, he said.

It's a mystery, but perhaps there's an answer somewhere in our DNA.
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the repugs better not read this as it will confuse them to the point of sitting in the corner sucking their thumbs.

[WillParkinson]

1. Can the New X-Men be far behind?!?!

:-)

[Odin2005]

2. Or they will misuse it for racist purposes.

How long before they use the distribution if variants of the Microcephalin gene to "prove" that Whites are smarter than Blacks?

[anonymous171]

5. Shouldn't really matter. Biological equality is a bad standard for equality anyways .

[Bitwit1234]

3. Mutated DNA does cause cancer/

It used to be that you have a family say four brothers. The DNA would chance just a little from each brother's line to the other. You could tell they were related and brothers. But then the DNA mutated and it causes cancer and other diseases. I wish I were younger. I would have made DNA my line of work. It is so so fascinating.

[Trillo]

4. It's the amazing shrinking brain! n/t