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Aboriginal Australians descended from early migration of modern humans out of Africa

Genome sequencing study suggests that Aboriginal Australians are descended from early wave of modern humans who migrated out of Africa perhaps 62,000 - 75,000 years ago

Little did he know that giving a team of scientists a lock of his hair would provide answers to some profound questions about the origins of humankind in his native Australia. But that is exactly what happened when scientists sequenced his genome and found that he was descended from a very ancient wave of modern humanity out of Africa and eventually into Australia some 62,000 - 75,000 years ago.

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© Science/AAASReconstruction of early spread of modern humans outside Africa. The tree shows the divergence of the Aboriginal Australian (ABR) relative to the CEPH European (CEU) and the Han Chinese (HAN) with gene flow between aboriginal Australasians and Asian ancestors. Purple arrowshows early spread of the ancestors of Aboriginal Australians into eastern Asia ~62,000 to 75,000 years B.P. (ka BP), exchanging genes with Denisovans, and reaching Australia ~50,000 years B.P. Black arrow shows spread of East Asians ~25,000 to 38,000 years B.P. and admixing with remnants of the early dispersal (red arrow) some time before the split between Asians and Native American ancestors ~15,000 to 30,000 years B.P. YRI, Yoruba.
He is an Aboriginal Australian. The results of the genetic tests showed that modern humans migrated into Eastern Asia in more than one wave and that he, along with all of his fellow Aboriginal Australians, could claim direct heritage with a very early wave, perhaps even the first wave. This meant that his population constituted one of the oldest continuous populations outside of Africa.

Pills

Scientists discover virus that kills all grades of breast cancer 'within seven days'

Scientists at the Penn State College of Medicine said this week they have discovered a virus that is capable of killing all grades of breast cancer "within seven days" of first introduction in a laboratory setting.

The virus, known as adeno-associated virus type 2 (AAV2), is naturally occurring and carried by up to 80 percent of humans, but it does not cause any disease.

Researchers learned of its cancer-killing properties in 2005, after Penn State scientists observed it killing cervical cancer cells. They also found that women who carried the AAV2 virus and human papillomavirus (HPV), which causes cervical cancer, had a lower propensity to develop cervical cancer.

When combined in a lab recently, AAV2 eradicated all the breast cancer cells "within seven days," according to researchers. Better still, it proved capable of wiping out cancer cells at multiple stages, negating the need for differing treatments used today.

Stop

Human skin embedded with spider silk can stop a bullet

Dutch artist Jalila Essaïdi and cell biologist Abdoelwaheb El Ghalbzouri have blended spider silk with human skin to produce material that is three times stronger than kevlar.


Question

Did Our Human "Super Brain" Suddenly Appear 75,000 Years Ago?

Super Brain
© The Daily Galaxy

There is mounting archaeological evidence for the evolution of a human "super-brain" no later than 75,000 years ago that spurred a modern capacity for novelty and invention, according to John Hoffecher, an archaeologist at the University of Colorado.

While the concept of a human super-brain is analogous to social insects like bees and ants, which collectively behave as a super-organism by gathering, processing, and sharing information about their environment, there is one important difference, Hoffecker said. "Human societies are not super-organisms -- they are composed of people who are for the most part unrelated, and societies filled with competing individuals and families."

While crude stone tools crafted by human ancestors beginning about 2.5 million years ago likely were an indirect consequence of bipedalism (walking upright) -- which freed up the hands for new functions -- the first inklings of a developing super-brain likely began about 1.6 million years ago when early humans began crafting stone hand axes, thought by Hoffecker and others to be one of the first external representations of internal thought.

The emerging modern mind in Africa was marked by a three-fold increase in brain size over 3-million-year-old human ancestors like Lucy, thought by some to be the matriarch of modern humans. Humans were producing perforated shell ornaments, polished bone awls and simple geometric designs incised into lumps of red ochre by 75,000 years ago. "With the appearance of symbols and language -- and the consequent integration of brains into a super-brain -- the human mind seems to have taken off as a potentially unlimited creative force," Hoffecker said.

Info

"Our Universe Continually Cycles through a Series of 'Aeons'"

Big Bang
© The Daily Galaxy
The circular patterns within the cosmic microwave background suggest that space and time did not come into being at the Big Bang but that our universe in fact continually cycles through a series of "aeons," according to University of Oxford theoretical physicist Roger Penrose, who says that data collected by NASA's WMAP satellite supports his idea of "conformal cyclic cosmology".

Penrose's finding runs directly counter to the widely accepted inflationary model of cosmology which states that the universe started from a point of infinite density known as the Big Bang about 13.7 billion years ago, expanded extremely rapidly for a fraction of a second and has continued to expand much more slowly ever since, during which time stars, planets and ultimately humans have emerged. That expansion is now believed to be accelerating due to a scientific X factor called dark energy and is expected to result in a cold, uniform, featureless universe.

Penrose, however, said Physics World, takes issue with the inflationary picture "and in particular believes it cannot account for the very low entropy state in which the universe was believed to have been born - an extremely high degree of order that made complex matter possible. He does not believe that space and time came into existence at the moment of the Big Bang but that the Big Bang was in fact just one in a series of many, with each big bang marking the start of a new "aeon" in the history of the universe."

The core concept in Penrose's theory is the idea that in the very distant future the universe will in one sense become very similar to how it was at the Big Bang. Penrose says that "at these points the shape, or geometry, of the universe was and will be very smooth, in contrast to its current very jagged form. This continuity of shape, he maintains, will allow a transition from the end of the current aeon, when the universe will have expanded to become infinitely large, to the start of the next, when it once again becomes infinitesimally small and explodes outwards from the next big bang. Crucially, he says, the entropy at this transition stage will be extremely low, because black holes, which destroy all information that they suck in, evaporate as the universe expands and in so doing remove entropy from the universe."

Info

Study Shows How Brain Buys Time For Tough Choices

Brain Images
© Frank Lab/Brown UniversityThe hotter the color, especially in the circled area, the more likely the brain was to take its time making difficult decisions. Parkinson’s patients whose deep brain stimulators were on (right), were more impulsive — a cooler blue.

Some people who receive deep brain stimulation for Parkinson's disease behave impulsively, making quick, often bad, decisions. New research published in Nature Neuroscience explains why, and shows that under normal circumstances key parts of the brain collaborate to buy time for careful consideration of difficult decisions.

Take your time. Hold your horses. Sleep on it.

When people must decide between arguably equal choices, they need time to deliberate. In the case of people undergoing deep brain stimulation (DBS) for Parkinson's disease, that process sometimes doesn't kick in, leading to impulsive behavior. New research into why that happens has led scientists to a detailed explanation of how the brain devotes time to reflect on tough choices.

Michael Frank, professor of cognitive, linguistic, and psychological sciences at Brown University, studied the impulsive behavior of Parkinson's patients when he was at the University of Arizona several years ago. His goal was to model the brain's decision-making mechanics. He had begun working with Parkinson's patients because DBS, a treatment that suppresses their tremor symptoms, delivers pulses of electrical current to the subthalamic nucleus (STN), a part of the brain that Frank hypothesized had an important role in decisions. Could the STN be what slams the brakes on impulses, giving the medial prefrontal cortex (mPFC) time to think?

"We didn't have any direct evidence of that," said Frank, who is affiliated with the Brown Institute for Brain Science. "To test that theory for how areas of the brain interact to prevent you from making impulsive decisions and how that could be changed by DBS, you have to do experiments where you record brain activity in both parts of the network that we think are involved. Then you also have to manipulate the system to see how the relationship between recorded activity in one area and decision making changes as a function of stimulating the other area."

Frank and his team at Brown and Arizona did exactly that. They describe their findings in a study published online in the journal Nature Neuroscience.

Telescope

A Year Of Sunrises

Hundreds of pictures of Earth, each taken at about 06:00 local time, show the terminator - the day/night line - over the course of one year. The Earth is tilted with respect to its orbit, the so the angle of the sunrise line tilts first one way and then the other over time.

You can see Africa and Saudi Arabia to the upper right, and clouds frantically changing each day.

The images were taken with the METEOSAT-9 Earth-observing satellite.


Credit: NASA Earth Observatory

Magnify

Resurrected mammalian protein is a potent antibiotic

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© Tom Brakefield/GettyHow clean is my pouch?
If modern medicine cannot provide an answer to multidrug-resistant microbes, perhaps ancient animals can. Biologists have resurrected a mammalian antimicrobial compound that was last seen on Earth 59 million years ago when mammals were recovering from the Cretaceous-Tertiary extinction that wiped out the dinosaurs. Even now it is potent enough to destroy some of our most troublesome pathogens.

Last year the Infectious Diseases Society of America launched an initiative with the aim of producing 10 antibiotics to tackle multidrug-resistant bugs by 2020. The lower reaches of the tree of life are being explored for those antibiotics, says Ben Cocks of La Trobe University in Bundoora, Australia.

Already, promising molecules have been found in the tissues of primitive fish called lampreys (Proceedings of the National Academy of Sciences, DOI).

Sun

Neutrinos may have traveled faster than the speed of light

Scientists at CERN, the world's largest physics lab, announced a startling finding yesterday that would be enough to make Albert Einstein roll over in his grave: Subatomic particles, called neutrinos, have been found to be traveling faster than the speed of light.
Cern 01
© Anja Niedringhaus - APCERN

Display

Scientists Use Brain Imaging to Reveal the Movies in Our Mind


Berkeley - Imagine tapping into the mind of a coma patient, or watching one's own dream on YouTube. With a cutting-edge blend of brain imaging and computer simulation, scientists at the University of California, Berkeley, are bringing these futuristic scenarios within reach.

Using functional Magnetic Resonance Imaging (fMRI) and computational models, UC Berkeley researchers have succeeded in decoding and reconstructing people's dynamic visual experiences - in this case, watching Hollywood movie trailers.

As yet, the technology can only reconstruct movie clips people have already viewed. However, the breakthrough paves the way for reproducing the movies inside our heads that no one else sees, such as dreams and memories, according to researchers.

"This is a major leap toward reconstructing internal imagery," said Professor Jack Gallant, a UC Berkeley neuroscientist and coauthor of the study published online today (Sept. 22) in the journal Current Biology. "We are opening a window into the movies in our minds."