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Living African group discovered to be the most populous humans over the last 150,000 years

New genetic research reveals that a small group of hunter-gatherers now living in Southern Africa once was so large that it comprised the majority of living humans during most of the past 150,000 years. Only during the last 22,000 years have the other African ethnicities, including the ones giving rise to Europeans and Asians, become vastly most numerous. Now the Khoisan (who sometimes call themselves Bushmen) number about 100,000 individuals, while the rest of humanity numbers 7 billion. Their lives and ways have remained unaltered for hundreds of generations, with only recent events endangering their hunter-gatherer lifestyles. The study's findings will be published in the journal Nature Communications on 4 December 2014.

By comparing nearly all the genes of these individuals -- their genomes -- with the genomes of 1,462 people from around the world, the researchers discovered that the inflow of new genes into the Khoisan peoples has been quite restricted the past 150,000 years, indicating that this large hunter-gatherer culture was physically isolated for most of its history and that its men typically did not take wives from outside the group.

"Khoisan hunter-gatherers in Southern Africa always have perceived themselves as the oldest people" said Stephan Schuster, a former Penn State University professor, now at Nanyang Technological University in Singapore and a leader of the research team, which includes scientists at Penn State and other research universities in the United States, Brazil, and Singapore. The Nature Communication paper analyzes five study participants from different tribes in Namibia. The study investigated 420,000 genetic variants across 1,462 genomes from 48 ethnic groups in populations worldwide. These analyses reveal that Southern African Khoisans are genetically distinct not only from Europeans and Asians, but also from all other Africans. The paper's first author Hie Lim Kim, formerly at Penn State and now at Nanyang Technological University, said "It is fascinating to unravel the population history of humankind over the last 150,000 years."

By conducting extensive computational analyses, the team demonstrated that two of the sequenced individuals showed no signs of having inherited any genetic material from members of other ethnic groups. Interestingly, these individuals are the oldest members of the Ju/'hoansi tribe, which still live in protected areas of Northwest Namibia. "This and previous studies show that the Khoisan peoples and the rest of modern humanity shared their most recent common ancestor approximately 150,000 years ago, so it was entirely unexpected to find that this group apparently did not intermarry with non-Khoisan neighbors for many thousand years," said Webb Miller, professor of Bioinformatics at Penn State and a member of the research team. "The current Khoisan culture and tradition, where marriage occurs either among Khoisan groups or results in female members leaving their tribes after marrying non-Khoisan men, appears to be long-standing."



Scientists reveal the ancient origins of drinking alcohol

There’s an emerging branch of research called Paleogenetics that tries to answer the questions of the present by scrutinizing the genetic material of the past. And when it comes to figuring out when drinking alcohol began — igniting both merriment and alcoholism — you need to go pretty far back: 10 million years. That was when some curious primate stumbled across a rotting piece of fruit and thought, “Why not?” And boom, drinking was born.

That’s at least how a new theory published in the Proceedings of the National Academy of Sciences describes it. The consumption of alcohol, which otherwise wouldn’t have been palatable and might have been poisonous, was an evolutionary boon when our ancestors descended from the trees and started looking for food.

“Evolutionary biologists such as myself study so much peculiar and fascinating examples of organisms adapting to their environment, there is a cliche in our field: ‘Life will find a way,’” lead author Matthew Carrigan wrote in an e-mail to The Washington Post. “So when I began this research, I thought, ‘If ethanol is present in naturally fermenting fruit, why shouldn’t some frugivores adapt the molecular machinery to digest it?”

At the center of this molecular machinery is an enzyme called ADH4. This is a very important enzyme: first, because it’s found in a primate’s throat, stomach, and tongue; and second, because it is the first enzyme that can metabolize alcohol, including ethanol and other alcohols found in plants. So Carrigan and other researchers went about the task of analyzing ADH4′s evolutionary history by resurrecting ancient enzymes, believing it would tell them when such consumption began.



U.N. rights experts seek review of U.S. police practices

Source: Reuters

United Nations human rights experts on Friday called for a halt to racial profiling by U.S. law enforcement officers and a review of laws allowing police to use lethal force.

The independent experts regretted that grand juries in the United States had failed to indict police officers for killing two unarmed black men in separate incidents that have led to mass protests.

Sending to trial the cases of Michael Brown in Ferguson, Missouri, and Eric Garner in New York would have brought all evidence to light and allowed justice to take its course, they said in a statement.

"I am concerned by the grand juries' decisions and the apparent conflicting evidence that exists relating to both incidents," said Rita Izsak, U.N. special rapporteur on minority issues.

Read more: http://www.reuters.com/article/2014/12/05/us-usa-new-york-un-idUSKCN0JJ1E620141205

2014 on track for best year for hiring since 1999

US employers are thought to have hired at another robust pace in November in the latest sign that the United States is outshining struggling economies throughout the developed world.

Analysts have forecast that the economy generated 225,000 jobs last month and that the unemployment rate remained 5.8%, according to a survey by FactSet. If those predictions prove generally accurate, November would mark the 10th straight month of strong US job gains above 200,000 and would put 2014 on track to be the best year for hiring since 1999.

The government will release the November employment report at 8:30 a.m. ET on Friday.

The improving US job market contrasts with weakness elsewhere around the globe. Growth among the 18 European nations in the euro alliance is barely positive, and the eurozone's unemployment rate is 11.5%. Japan is in recession.

Read more: http://www.businessinsider.com/a-strong-us-jobs-would-put-hiring-in-1999-territory-2014-12

Friday TOON Roundup 3 - The Rest







Friday TOON Roundup 2 - Black and White

Friday TOON Roundup 1 - Choked to death

Is HIV Evolving Into A Weaker Virus?

Viruses are masters at mutating.

So the big concern with deadly viruses, like Ebola and hepatitis C, is that they will evolve into more dangerous forms over time.

It looks like just the opposite is happening with HIV — although it's happening slowly.

"HIV can generate any mutation in the book, on any day," says virologist Philip Goulder at the University of Oxford.

Over a 10-year period, HIV has picked up mutations that make it slightly less virulent in parts of southern Africa, Goulder and his team reported Monday in the Proceedings of the National Academy of Sciences.

That means it could take a little longer for some people to develop AIDS if they don't get HIV treatment. The mutations push back the average time to develop AIDS in Botswana from about 10 years to about 12.5 years, Goulder says.



Teacher orders third-grader to unclog toilet with bare hands

OTHELLO, Wash. – A Washington state teacher acknowledged ordering an 8-year-old student to unclog a toilet with his bare hands, and the boy’s parents say the educator deserves more than a reprimand.

Artie and Lisa Adams tell KEPR-TV that they learned of the Nov. 6 incident at Scootney Springs Elementary School in the small city of Othello when they asked their son about his day at school.

The third-grader said he reported the clog and teacher Brent Taylor told him to clear it with his bare hands.

The parents complained. The principal reprimanded Taylor and ordered the 23-year teaching veteran to review a hygiene course. Othello Superintendent George Juarez says he stands by the principal’s decision.



Tom the Dancing Bug TOON: Existing While Black

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