The largest study ever conducted of DNA evidence extracted from long-dead woolly mammoths points to a rockier past for the iconic Ice Age giants than many had suspected. The last mammoths left in Siberia 50,000 to 5,000 years ago weren't natives, they report in the September 4th Current Biology. Rather, they were North Americans that had migrated in and replaced the dwindling Siberian populations.

In the new study, the researchers analyzed mitochondrial DNA from 160 mammoth samples from across Holarctica (a region encompassing present day North America, Europe and Asia), representing most of radiocarbon time.

Down Syndrome (DS) belongs to the group of conditions called 'aneuploidies', defined by an abnormal loss or gain of genetic material, i.e. fragments of chromosomes or whole chromosomes. Aneuploidies cause congenital anomalies that are a prime cause of infant death in Europe and the USA, and are currently on the increase with advancing maternal age in European countries. The number of people with DS in Europe exceeds half a million.

The condition is more common than muscular dystrophy and cystic fibrosis, but the development of new therapeutic concepts is hindered by the fact that unlike muscular dystrophy and cystic fibrosis, where a single mutated gene causing the disease is known, the entire human chromosome 21 (containing around 300 genes) still has to be dissected into individual gene-dose contributions to the DS symptoms.

Scientists investigating the mechanisms of Down Syndrome have revealed the earliest developmental changes in embryonic stem cells caused by an extra copy of human chromosome 21 – the aberrant inheritance of which results in the condition. Their study is published in the American Journal of Human Genetics.

Astronomers have taken the closest look ever at the giant black hole in the center of the Milky Way. By combining telescopes in Hawaii, Arizona, and California, they detected structure at a tiny angular scale of 37 micro-arcseconds - the equivalent of a baseball seen on the surface of the moon, 240,000 miles distant. These observations are among the highest resolution ever done in astronomy.

Using a technique called Very Long Baseline Interferometry (VLBI), a team of astronomers led by Doeleman employed an array of telescopes to study radio waves coming from the object known as Sagittarius A* (A-star). In VLBI, signals from multiple telescopes are combined to create the equivalent of a single giant telescope, as large as the separation between the facilities. As a result, VLBI yields exquisitely sharp resolution.

The Sgr A* radio emission, at a wavelength of 1.3 mm, escapes the galactic center more easily than emissions at longer wavelengths, which tend to suffer from interstellar scattering. Such scattering acts like fog around a streetlamp, both dimming the light and blurring details. VLBI is ordinarily limited to wavelengths of 3.5 mm and longer; however, using innovative instrumentation and analysis techniques, the team was able to tease out this remarkable result from 1.3-mm VLBI data.

Yale molecular and evolutionary biologists in collaboration with Department of Energy scientists produced the full genome sequence of Trichoplax, one of nature's most primitive multicellular organisms, providing a new insight into the evolution of all higher animals.

The findings reported in Nature show that while Trichoplax has one of the smallest nuclear genomes found in a multi-cellular creature, it contains signature sequences for gene regulation found in more complex animals and humans. Further, it defines Trichoplax as a branching point of animal evolution.

A new study has found that mothers who delivered vaginally compared to caesarean section delivery (CSD) were significantly more responsive to the cry of their own baby, identified through MRI brain scans two to four weeks after delivery.

The results of the study in The Journal of Child Psychology and Psychiatry suggest that vaginal delivery (VD) mothers are more sensitive to own baby-cry in the regions of the brain that are believed to regulate emotions, motivation and habitual behaviors.

In one week from today, the Large Hadron Collider(LHC) will take its first step 'back in time.' What is mass? What happened at the beginning of the universe? Are there other dimensions? We'll be on the way to finding out.

It's taken about 6,000 researchers, been over budget and behind schedule but it's finally ready to go.

If all goes according to plan, the superconducting magnets in the collider will zap atomic particles around the 17-mile tunnel at roughly the speed of light. Then the scientists will smash the particles together, replicating what happened mere nanoseconds after the first big bang.