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From DNA, scientists create skull of Neanderthal cousinScientists say they've deciphered features of the skull and some other details of a mysterious, extinct cousin of Neanderthals by analyzing its DNA. The genetic material came from the finger bone of a female member of the Denisovans, a population known mostly from small bone fragments and teeth recovered in Siberia's Denisova Cave. Denisovans may have occupied that cave from more than 200,000 years ago to around 50,000 years ago.

New study links anemia in early pregnancy to higher autism risk in childrenNew European research has found that women who suffer from anemia in early pregnancy, a condition which is usually more common in late pregnancy, may give birth to children who have a higher risk of autism and attention deficit hyperactivity disorder (ADHD). Carried out by researchers at the Karolinska Institutet, Sweden, the new study looked at 532,232 Swedish children and their 299,768 mothers to look at what effect the timing of an anemia diagnosis during pregnancy had on the fetus's neurodevelopment.

How to Cool a Planet With Extraterrestrial DustExtraterrestrial events -- the collision of faraway black holes, a comet slamming into Jupiter -- evoke wonder on Earth but rarely a sense of local urgency. By and large, what happens in outer space stays in outer space.A study published Wednesday in Science Advances offered a compelling exception to that rule. A team of researchers led by Birger Schmitz, a nuclear physicist at Lund University in Sweden, found that a distant, ancient asteroid collision generated enough dust to cause an ice age long ago on Earth. The study lends new insight to ongoing efforts to address climate change."We've shown that what happens in the solar system can have a big influence on Earth," said Philipp Heck, a curator of meteorites at the Field Museum of Natural History in Chicago and an author of the study. "Extraterrestrial events aren't always destructive. Many people think about meteorites as just dinosaur killers, but we found the opposite. A big collision in the asteroid belt had constructive consequences that led to cooling and biodiversification."Earth is frequently exposed to extraterrestrial matter; 40,000 tons of the stuff settle on the planet every year, enough to fill 1,000 tractor-trailers. But 466 million years ago, a 93-mile-wide asteroid collided with an unknown, fast-moving object between Mars and Jupiter. The crash increased the amount of dust arriving on Earth for the next 2 million years by a factor of 10,000. Schmitz, Heck and their team found that the dust triggered cooling in Earth's atmosphere that led to an ice age.In sufficient amounts, extraterrestrial dust can cool Earth by blocking the amount of solar radiation that reaches the surface. Because the dust from the asteroid collision accumulated gradually, the planet cooled gradually, allowing plant and animal species to adapt as sea levels dropped and temperatures declined by as much as 50 degrees Fahrenheit."Our study is the first time it has been shown that asteroid dust actually helps cool Earth to a dramatic extent," Schmitz said.The team derived their evidence from a study of fossil meteorites, extraterrestrial materials that long ago became embedded in Earth's rocks. They are so rare, Heck called them "Mona Lisas."The first was found in a Swedish limestone quarry in 1952, but it was shelved by an unsuspecting paleontologist and wasn't properly identified for another 27 years. In 1979, when a mineralogist realized the extraterrestrial origins of the rock, he prompted a systematic search for more in Swedish quarries. Researchers found 130 meteorites over the next two decades.Of these, Schmitz and his team determined that 129 derived from the same asteroid breakup. The meteorites were analyzed to determine their chemical composition, and their level of cosmic ray exposure was measured to confirm their outer-space origins and pin down when they arrived on Earth.By tracing the increase in the meteorites of certain isotopes, researchers were able to determine that extraterrestrial dust began to reach Earth about 50,000 years after the asteroid collision. A worldwide ice age began roughly 10,000 years later, during the Ordovician Period."We're talking about gentle changes that happened over 2 million years," Heck said. "If we could travel back in time, it wouldn't appear as a catastrophe to us; it would be more like a gentle nudge that led to global change and triggered diversification."When the team started its research, they hypothesized that the collision might have increased dust levels by a hundredfold. The chemical analysis soon revealed that dust levels had risen far more, by a factor of 10,000, an increase sufficient to markedly alter Earth's climate.Schmitz and his team believe their findings shed light on a mechanism that could eventually be used to counteract global warming. In their paper, they proposed that an asteroid could be captured and brought to one of the Lagrange points between the sun and Earth -- an unstable zone where the gravitational pull of each is equal -- allowing it to produce dust that blocks sunlight. They are not the first scientists to suggest using extraterrestrial dust for global cooling.However, Heck emphasized that their findings are only a basis for investigation. "Putting a rock into an unstable point that could make it fall into Earth has me worried," he said. "A small asteroid wouldn't cause a global extinction, but it could cause a local catastrophe or wipe out a city in the worst case."At the very least, Schmitz said, the study will help people appreciate Earth's connection to the rest of the solar system: "Geologists often think of nothing outside Earth. You have to understand what happens in space to get the full picture of what's happened on Earth."This article originally appeared in The New York Times.(C) 2019 The New York Times Company

Post-menopausal women should monitor their cholesterol levels says new studyAustralian researchers are advising post-menopausal women to keep an eye on their cholesterol, after finding that levels appear to increase after menopause. Carried out by researchers from the Australian National University (ANU), the new study analyzed 66 studies which looked at cholesterol levels of 68,394 pre-menopausal women and 46,261 post-menopausal, a total of 114,655 participants. The findings, published in the journal Menopause, showed that post-menopausal women had significantly higher cholesterol levels than pre-menopausal women, including triglycerides, total cholesterol, and LDL cholesterol, the "bad" cholesterol which helps transport fat molecules around the body.

Solar panels, vegan diets, no flights: meet America's climate revolutionariesThe last time Californian climate scientist Peter Kalmus was on an airplane was in 2012: He says it made him feel physically sick and like he was "stealing" from his children's future, and vowed never to fly again. US President Donald Trump's administration has made no secret of its disdain for climate science, but that hasn't stopped some ordinary Americans from finding ways to drastically reduce their own carbon footprints, hoping to persuade others through their examples. Kalmus was pursuing his post-doctoral studies in 2009 when he became increasingly concerned about the prospect of climate breakdown, tipping points such as the thawing of the Earth's permafrost triggering runaway global warming that wreaks havoc on weather systems.

Archaeologists in Bolivia find 400 year old Tiwanaku vesselsPre-Hispanic vessels over 400 years old have been found in the center of Bolivia's Tiwanaku ruins, archaeologists said Wednesday. The finding was made at the Kalasasaya temple during a research, conservation and restoration project undertaken with the support of UNESCO on the grounds of the ancient city, which is about 47 miles (75 kilometers) from the capital of La Paz, near the southern shore of Lake Titicaca.


Ocean power: A green option failing to make wavesInaugurated at La Richardais on the west coast by Charles de Gaulle in 1966, the plant produces about 500 Gigawatt hours of electricity per year -- enough to power 250,000 out of France's 30 million-odd households. It remains the sole power station of its type in France and one of only two large-scale tidal plants in the world -- the second largest after the Sihwa scheme inaugurated in South Korea seven years ago. "Ocean renewable energy has huge global potential, but is a largely untapped resource," Simon Neill of Bangor University's School of Ocean Sciences in Wales told AFP.

Teen activist to lawmakers: Try harder on climate changeSwedish teenager Greta Thunberg offered a blunt message to Congress on Tuesday as she brought her campaign for urgent action on climate change to the U.S. Capitol. "I know you're trying," she told Democratic senators at an invitation-only forum, "but just not hard enough. Massachusetts Sen. Ed Markey thanked the 16-year-old activist for her advice and her activism, which has gained worldwide attention by inspiring a series of protests and school strikes, including one set for Friday.


One in 16 American women forced into first sexual encounter: studyOne in 16 American women were either forced or coerced into their first sexual encounter, according to a study investigating the long-term negative impacts of such "trauma" on women's health. In the US, "the #MeToo movement has highlighted how frequently women experience sexual violence," the researchers wrote in the introduction. Published Monday in the American Medical Association's peer-reviewed journal (JAMA Internal Medicine), the study is based on a sample of more than 13,000 women aged 18 to 44, who were interviewed as part of a survey conducted between 2011 and 2017 by the Centers for Disease Control and Prevention (CDC).

Black carbon from air pollution found in placentas: studyBlack carbon particles typically emitted by vehicle exhaust and coal-fired power plants have been detected on the foetus-facing side of placentas, researchers said Tuesday. The concentration of particles was highest in the placentas of women most exposed to airborn pollutants in their daily life, according to a study in Nature Communications. "Our study provides compelling evidence for the presence of black carbon particles originating from air pollution in human placenta," the authors said.

Space Talent puts jobs at Blue Origin, SpaceX and elsewhere in one big databaseJeff Bezos' Blue Origin space venture and Elon Musk's SpaceX are often at odds, but there's at least one place where those two space-industry rivals are on the same page: the newly unveiled Space Talent job database. The search engine for careers in the space industry is a project of Space Angels, a nationwide network designed to link angel investors with space entrepreneurs. "If you've ever considered working in space, this jobs board has 3,000 reasons to make the leap," Space Angels CEO Chad Anderson said in a tweet. The database aggregates job postings from Blue Origin and SpaceX as… Read More

Scientists discover the 'most massive neutron star ever detected'Astronomers have discovered the "most massive neutron star ever measured," amassing to more than two times the mass of our sun, that they dub "almost too massive to exist," according to a statement from researchers at the Green Bank Observatory. "A neutron star is what remains when a very massive star goes supernova and dies, it is an extremely dense dead stellar core," Thankful Cromartie, 27, a graduate student at the University of Virginia and Grote Reber pre-doctoral fellow at the National Radio Astronomy Observatory, as well as lead author on the study published Monday in Nature Astronomy, explained to ABC News. Cromartie and her colleagues at the NANOGrav Physics Frontiers Centered measured the neutron star, dubbed J0740+6620, as 2.17 times the mass of our sun but packed into a sphere only 30 kilometers (approximately 18 miles) wide.