The Real Question: Who Didn't Have Sex with Neanderthals?
The only modern humans whose ancestors did not interbreed with Neanderthals are apparently sub-Saharan Africans, researchers say.
New findings suggest modern North Africans carry genetic traces from Neanderthals, modern humanity's closest known extinct relatives. Although modern humans are the only surviving members of the human lineage, others once roamed the Earth, including the Neanderthals. Genetic analysis of these extinct lineages’ fossils has revealed they once interbred with our ancestors, with recent estimates suggesting that Neanderthal DNA made up 1 percent to 4 percent of modern Eurasian genomes. Although this sex apparently only rarely produced offspring, this mixing was enough to endow some people with the robust immune systems they enjoy today. |  |
HUMAN EXPANSION FROM AFRICA COMES INTO FOCUS
A new, comprehensive review of human anthropological and genetic records gives the most up-to-date story of the “Out of Africa” expansion that occurred about 45,000 to 60,000 years ago.
This expansion, detailed by three Stanford geneticists Henn, Cavalli-Sforza, and Feldman presents an up-to-date version of the model. In the recent study is published in this edition of the Proceedings of the National Academy of Sciences they conclude it had a dramatic effect on human genetic diversity, which persists in present-day populations. As a small group of modern humans migrated out of Africa into Eurasia and the Americas, their genetic diversity was substantially reduced.
This expansion, detailed by three Stanford geneticists Henn, Cavalli-Sforza, and Feldman presents an up-to-date version of the model. In the recent study is published in this edition of the Proceedings of the National Academy of Sciences they conclude it had a dramatic effect on human genetic diversity, which persists in present-day populations. As a small group of modern humans migrated out of Africa into Eurasia and the Americas, their genetic diversity was substantially reduced.
Singing Sand Dunes Explained
When Marco Polo heard it in China, he suspected evil spirits. When residents of Copiapo, Chile, heard it emanating from a sandy hill, they dubbed the peak El Bramador, for its roars and bellows.
Scientists today call it "singing sand," but they're all referring to the same thing: As sand grains shuffle down the slopes of certain sand dunes, they produce a deep, groaning hum that reverberates for miles.
But how these dunes produce this "music" remains a much debated mystery. Another vexing question is why different dunes sing different tunes—and how can some even sing more than one note at a time?.
Scientists today call it "singing sand," but they're all referring to the same thing: As sand grains shuffle down the slopes of certain sand dunes, they produce a deep, groaning hum that reverberates for miles.
But how these dunes produce this "music" remains a much debated mystery. Another vexing question is why different dunes sing different tunes—and how can some even sing more than one note at a time?.
Mother convicted over cannabis in breast milk
A woman has been convicted of giving cannabis to her 3-month old baby through her breast milk, in what is believed to be the first case of its kind in New Zealand.
The 29-year-old Wanganui woman was charged with administering a class C controlled drug, namely cannabis, to a person under the age of 18. |  |
Plants recognise pathogenic and beneficial microorganisms
Plant roots are surrounded by thousands of bacteria and fungi living in the soil and on the root surface. To survive in this diverse environment, plants employ sophisticated detection systems to distinguish pathogenic microorganisms from beneficial microorganisms.
Here the so-called chitin molecules from microorganisms, along with modified versions, play an important role as they are detected by the plant surveillance system. Legumes, for example, build a defence against pathogenic microorganisms in response to simple chitin molecules.
Here the so-called chitin molecules from microorganisms, along with modified versions, play an important role as they are detected by the plant surveillance system. Legumes, for example, build a defence against pathogenic microorganisms in response to simple chitin molecules.
Europe's oldest prehistoric town unearthed in Bulgaria
Archaeologists in Bulgaria say they have uncovered the oldest prehistoric town found to date in Europe.
The walled fortified settlement, near the modern town of Provadia, is thought to have been an important centre for salt production. Its discovery in north-east Bulgaria may explain the huge gold hoard found nearby 40 years ago. Archaeologists believe that the town was home to some 350 people and dates back to between 4700 and 4200 BC. |  |
SISTINE CHAPEL AT 500 YEARS: THREATENED BY TOURISM
Michelangelo's Sistine chapel frescoes are threatened by the effects of too many visitors, experts have warned on Wednesday, as the masterly painted ceiling celebrated its 500th anniversary.
"The anthropic pressure with dust, the humidity of bodies, carbon dioxide produced by perspiration can cause discomfort for the visitors and, in the long run, damage to the paintings," Antonio Paolucci, director of the Vatican Museums, wrote in the Vatican newspaper L'Osservatore Romano. |  |
Medieval female skeleton dug up; it may be church founder
A skeleton found in the same boneyard where English King Richard III may have been buried might be one of the founders of the Church of the Grey Friars, archaeologists announced Tuesday.
Scientists have yet to examine the female skeleton, though they are subjecting a male skeleton suspected to be Richard III's to rigorous testing. Nevertheless, the researchers said it was no surprise to find a woman buried at the medieval church in Leicester, England. |  |
Five Early Primates You Should Know
Finding the earliest primates isn’t easy. The first members or our order probably lived about 65 million years ago and were rat-sized critters known mainly from teeth. With such scant evidence, researchers have had a hard time classifying these creatures and making connections to modern primates. Still, scientists have identified dozens of early primate, or probable primate, species. If you’re unfamiliar with our earliest origins, here are five primates to know.
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When People Worry About Math, the Brain Feels the Pain
Mathematics anxiety can prompt a response in the brain similar to when a person experiences physical pain, according to new research at the University of Chicago.
Using brain scans, scholars determined that the brain areas active when highly math-anxious people prepare to do math overlap with the same brain areas that register the threat of bodily harm -- and in some cases, physical pain. "For someone who has math anxiety, the anticipation of doing math prompts a similar brain reaction as when they experience pain -- say, burning one's hand on a hot stove," said Sian Beilock, professor of psychology at the University of Chicago and a leading expert on math anxiety. |  |
Storm kills NYU lab mice, crippling medical research
One of New York University's medical research facilities has lost thousands of laboratory mice to Hurricane Sandy's storm surge, a research setback that could take years to correct, according to scientists.
The NYU Langone Medical Center confirmed on Wednesday that the Smilow Research Center, one of three animal research facilities on campus, "was adversely impacted by the severity of the flood surge and the speed with which it came on.". |  |
We must heed the warnings from superstorm Sandy
AS New Scientist goes to press, north-east North America is reeling in the aftermath of superstorm Sandy. People are dead, millions are without electricity and damage estimates top $20 billion. And that is far from the full impact. Over the next few weeks, the true extent will become clear to millions of people who must now clean up. Whether the implications are clear to their leaders is another question.
Oddly, the lesson of Sandy is the same as the lesson of the Eurozone crisis and other recent events such as the Egyptian revolution: complex systems play by their own rules. You can't manage them in a linear way. We live in a web of systems: if one falls, it takes others with it.
Oddly, the lesson of Sandy is the same as the lesson of the Eurozone crisis and other recent events such as the Egyptian revolution: complex systems play by their own rules. You can't manage them in a linear way. We live in a web of systems: if one falls, it takes others with it.
"Geoengineers" Think They Can Save the Planet with High-Risk Projects
For almost 20 years, I’ve been spending time on a craggy stretch of British Columbia’s shoreline called the Sunshine Coast. This summer, I had an experience that reminded me why I love this place, and why I chose to have a child in this sparsely populated part of the world.
It was 5 a.m. and my husband and I were up with our 3-week-old son. Looking out at the ocean, we spotted two towering, black dorsal fins: orcas, or killer whales. Then two more. We had never seen an orca on the coast, and never heard of their coming so close to shore. In our sleep-deprived state, it felt like a miracle, as if the baby had wakened us to make sure we didn’t miss this rare visit.
It was 5 a.m. and my husband and I were up with our 3-week-old son. Looking out at the ocean, we spotted two towering, black dorsal fins: orcas, or killer whales. Then two more. We had never seen an orca on the coast, and never heard of their coming so close to shore. In our sleep-deprived state, it felt like a miracle, as if the baby had wakened us to make sure we didn’t miss this rare visit.
Police allowed to install cameras on private property without warrant
A federal judge has ruled that police officers in Wisconsin did not violate the Fourth Amendment when they secretly installed cameras on private property without judicial approval.
The officers installed the cameras in an open field where they suspected the defendants, Manuel Mendoza and Marco Magana, were growing marijuana. The police eventually obtained a search warrant, but not until after some potentially incriminating images were captured by the cameras. The defendants have asked the judge to suppress all images collected prior to the issuance of the search warrant.
The officers installed the cameras in an open field where they suspected the defendants, Manuel Mendoza and Marco Magana, were growing marijuana. The police eventually obtained a search warrant, but not until after some potentially incriminating images were captured by the cameras. The defendants have asked the judge to suppress all images collected prior to the issuance of the search warrant.
FATAL DISTRACTION: CAN UFOS CAUSE AIR ACCIDENTS?
Pilots have been seeing unexplained things outside their cockpit windows since the dawn of aviation.
One of the most legendary examples happened near the end of World War II when both Allied and German pilots reported seeing fiery glowing objects that followed their planes and then disappeared in wild maneuvers. The sky phantoms were nicknamed foo-fighters (long before the 1990s alternative rock band), and thought to be secret military weapons. The term "UFO" didn't appear until a few years later -- at the height of anticipation over the eventuality of human space travel. |  |
People May Be Just a Bit Psychic, Even They Don’t Know It
WALL STREET JOURNAL
Scientists understandably don’t have much patience for the notion of extrasensory perception. Yet evidence persists in the psychological literature that people’s bodies sometimes unconsciously “predict” unpredictable future events. These visceral responses don’t appear to be the result of sheer chance.
That’s the result of a meta-analysis of earlier papers on this subject conducted by a trio of researchers led by Julia Mossbridge of Northwestern University.
That’s the result of a meta-analysis of earlier papers on this subject conducted by a trio of researchers led by Julia Mossbridge of Northwestern University.
Monsters Are People Too, Says Dungeons And Dragons Study
A pair of eyes in front of us automatically lures our own gaze, even if they belong to an animal. But what about a monster with multiple eyes located not on the head, but on its hands or legs or torso? Where do we first look?
The question is neither straightforward nor silly. Brains are complex things, and so are the faces that eyes are often tucked into. Dolphins, dogs, monkeys, birds, goats, people and other organisms, for example, are primed to automatically follow the gaze of both familiar and unfamiliar species. But we don’t know how this widespread gaze-recognition circuitry works, or what image draws our attention. Is it the eyes themselves, or their typical central location, or the complexities of face, or something else?. |  |
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