USA Today News » Science US Newspaper site Tue, 23 Apr 2013 20:22:11 +0000 en-US hourly 1 Modern Europe’s Genetic History Starts in Stone Age – National Geographic News – National Geographic Tue, 23 Apr 2013 20:21:35 +0000 admin

Europeans as a people are younger than we thought, a new study suggests.

DNA recovered from ancient skeletons reveals that the genetic makeup of modern Europe was established around 4,500 years ago in the mid-Neolithic, and not by the first farmers who arrived in the area around 7,500 years ago or by earlier hunter-gatherer groups. (Read about Europes oldest known town.)

“The genetics show that something around that point caused the genetic signatures of previous populations to disappear,” said Alan Cooper, director of the Australian Centre for Ancient DNA at the University of Adelaide, where the research was performed.

“However, we don’t know what happened or why, and [the mid-Neolithic] has not been previously identified as [a time] of major change,” he said.

Furthermore, the origins of the mid-Neolithic populations that did form the basis of modern Europe are also unknown.

“This population moves in around 4,000 to 5,000 years ago, but where it came from remains a mystery, as we can’t see anything like it in the areas surrounding Europe,” Cooper said.

The surprising findings are part of a new study, published in this week’s issue of the journal Nature Communications, that provides the first detailed genetic history of modern Europe.

The study shows that “relatively recent migrations seem to have had a significant genetic impact on the population of Central Europe,” said study co-author Spencer Wells, who leads National Geographics Genographic Project. (Read about Europe’s “Wild Men” in National Geographic magazine.)

Genetic Signature

In the study, Cooper and his colleagues extracted mitochondrial DNA—which children inherit only from their mothers—from the teeth and bones of 39 skeletons found in central Germany. The skeletons ranged in age from about 7,500 to 2,500 years old.

The team focused on a group of closely related mitochondrial lineages—mutations in mitochondrial DNA that are similar to one another—known as haplogroup H, which is carried by up to 45 percent of modern Europeans.

Cooper and his colleagues focused on haplogroup H because previous studies have indicated the mutations might have been present in Europeans’ genetic makeup for several thousand years.

It’s unclear how this haplogroup became dominant in Europe. Some scientists have proposed that it spread across the continent following a population boom after the end of the last Ice Age about 12,000 years ago.

But the new data paint a different picture of the genetic foundation of modern Europe: Rather than a single or a few migration events, Europe was occupied several times, in waves, by different groups, from different directions and at different times.

The first modern humans to reach Europe arrived from Africa 35,000 to 40,000 years ago.By about 30,000 years ago, they were widespread throughout the area while their close cousins, the Neanderthals, disappeared. Hardly any of these early hunter-gatherers carried the H haplogroup in their DNA.

About 7,500 years ago during the early Neolithic period, another wave of humans expanded into Europe, this time from the Middle East. They carried in their genes a variant of the H haplogroup, and in their minds knowledge of how to grow and raise crops. (Related: Egypts Earliest Farming Village Found.)

Archeologists call these first Central European farmers the linear pottery culture (LBK)—so named because their pottery often had linear decorations.

The genetic evidence shows that the appearance of the LBK farmers and their unique H haplogroups coincided with a dramatic reduction of the U haplogroup—the dominant haplogroup among the hunter-gatherers living in Europe at that time.

Farmers Move In

The findings settle a longstanding debate among archaeologists, said Wells, who is also a National Geographic explorer-in-residence.

Archaeology alone can’t determine whether cultural movements—such as a new style of pottery or, in this case, farming—were accompanied by the movements of people, Wells said in an email.

“In this study we show that changes in the European archaeological record are accompanied by genetic changes, suggesting that cultural shifts were accompanied by the migration of people and their DNA.”

The LBK group and its descendants were very successful and spread quickly across Europe. “They became the first pan-European culture, if you like,” Cooper said.

Given their success, it would be natural to assume that members of the LBK culture were significant genetic ancestors of many modern Europeans.

But the team’s genetic analysis revealed a surprise: About 4,500 years ago in the mid-Neolithic, the LBK culture was itself displaced. Their haplogroup H types suddenly becamevery rare, and they were subsequently replaced by populations bearing a different set ofhaplogroup H variations.

Mysterious Turnover

The details of this “genetic turnover” event are murky. Scientists don’t know what prompted it, or even where the new colonizers came from.

“The extent or nature of this genetic turnover are not clear, and we don’t know how widespread it is,” Cooper said.

If this turnover were widespread, it could have been prompted by climate change or disease, he said.

“All we know is that the descendants of the LBK farmers disappeared from Central Europe about 4,500 years ago, clearing the way for the rise of populations from elsewhere, with their own unique H signatures.”

Peter Bogucki, an archeologist at Princeton University who has studied early farming societies in Europe, called the finding “really interesting” and noted the timing of the genetic turnover is curious.

“At the end of the fifth millennium—[about] 4,000 years ago—there are a lot of changes in the archeological record,” said Bogucki, who was not involved in the study.

For example, the long houses that LBK farmers and their descendants favored became less common. Also, the settlement patterns of people living in Central Europe began changing, as did their stone tools.

“There are major transformations during this time that haven’t really been all that well explained in interior Central Europe,” Bogucki said.

“It looks like the whole system of agricultural settlement that got established with the LBK ran its course through the fifth millennium and something caused people to change.”

Of Unknown Origins

Bogucki agrees that climate change might have been a trigger for the change in Europe’s genetic makeup, but he thinks it was only a factor and not the sole cause.

One thing that is clear from the genetic data is that nearly half of modern Europeans can trace their origins back to this mysterious group.

“About [4,500] years ago, you start seeing a diversity and composition of genetic signatures that are beginning to look like modern [Central] Europe,” Cooper said. “This composition is then modified by subsequent cultures moving in, but it’s the first point at which you see something like the modern European genetic makeup in place.”

Whatever prompted the replacement of genetic signatures from the first pan-European culture, Cooper is clearly intrigued. ”Something major happened,” he said in a statement, “and the hunt is now on to find out what that was.”

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Microraptor terrorized land and water new dino research reveals – SlashGear Tue, 23 Apr 2013 20:21:34 +0000 admin

It might sound like a killer drone, but the Microraptor was in fact an airborne terror that could harass fish as much as it did birds and mammals in the Cretaceous period, new dinosaur research has discovered. The flying dinosaur, known to be roughly the size of a hawk, had previously been believed to feed exclusively on what it could seize from the trees, but preserved stomach content examined by a team at the University of Alberta, Science Daily reports, revealed its appetites were far wider ranging.


The fossil was discovered in China, where it had been preserved in volcanic ash. That meant its stomach contents were preserved, which allowed the research team to identify fish remnants and overturn previous assumptions about the Microraptor’s diet, as well as where it lived and hunted.

“Now we know that Microraptor operated in varied terrain and had a varied diet,”Scott Persons, graduate student at the University of Alberta, said of the findings. Earlier evidence had suggested that the flying dinosaur stuck to the birds and squirrel-sized mammals it could find in trees.

“It took advantage of a variety of prey in the wet, forested environment that was China during the early Cretaceous period, 120 million years ago” Persons concluded, pointing out that the dinosaur’s teeth were, in fact, adapted to a mixed diet. Serrations on one side, with a forward-facing angle that allowed it to more quickly swallow fish after having dived down and scooped them out of the water.

The new discovery is notable because it makes Microraptor the first known flying raptor to prey on fish. The species is perhaps best known for featuring in Jurassic Park, though the film took liberties with the dinosaur’s anatomy, making it larger than in reality and missing out the feathers that would have covered a Velociraptor’s body.

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Comet Could Blast Earth With Weird Meteor Shower – Discovery News Tue, 23 Apr 2013 20:21:34 +0000 admin

A small but incredibly bright comet heading toward the sun could do more than dazzle Earth’s skies when it arrives later this year. Scientists say Comet ISON, already shedding dust at the prodigious rate of about 112,000 pounds per minute, could spark an unusual meteor shower.

Computer simulations predicting the location and movement of the comet’s dust trail show Earth will be passing through the fine-grained stream around Jan. 12, 2014.

Some of the particles, which are smaller in diameter than a red blood cell, should be pushed back by the pressure of sunlight, allowing them to be captured by Earth’s gravity when the planet plows through the largely invisible stream.

PHOTOS: Close Encounters with Comets

“As the comet passes Earth’s orbit going into the sun, you’ll have particles trailing behind it. But since it’s passing so close to the sun, you’re also going to have particles pushed away by the pressure of the sunlight. That means we’ll have particles coming outward and also falling inward. We don’t often deal with particles that come both directions,” said Bill Cooke, lead scientist at NASA’s Meteoroid Environment Office at the Marshall Space Flight Center in Huntsville, Ala.

The particles are so small that even though they will hit the atmosphere at about 125,000 mph, instead of burning up, triggering so-called “shooting stars,” they will be stopped entirely, predicts astronomer Paul Wiegert, with the University of Western Ontario in Canada.

The only visible and detectable sign of the comet dust might be a proliferation of bright blue clouds at the edge of space. Scientists suspect these so-called noctilucent, or “night-shining” clouds are be seeded by dust in the upper atmosphere.

PHOTOS: Russian Meteor Strike Aftermath

Eventually, the trapped comet dust will make its way — silently and invisibly — to the planet’s surface.

Comet ISON, which was discovered in September 2012 by amateur astronomers in Russia, is believed to be making its first swing into the inner solar system, so unlike repeat fliers, it hasn’t laid down a rich dust trail from previous orbits for Earth to fly through.

ISON is an acronym for the telescope the astronomers were using, the International Scientific Optical Network.

ANALYSIS: Awesome Mars-Comet Impact Less Likely

If the comet survives — and that’s a big if — the comet will about 700,000 miles above the surface of the sun when it makes its closest approach on Nov. 28. The closest it will come to Earth will be about 40 million miles on Dec. 26.

A comet in the 1970s passed 10 times farther away from the sun than ISON’s orbit and partially disintegrated, noted Cooke.

“ISON may very well not survive. I guess we won’t know for sure until we look for it to come out from behind the sun,” Cooke told Discovery News.

Currently the comet is about 280 million miles away from Earth and approaching the outer part of the asteroid belt.

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Watch: SpaceX Grasshopper hovers 820 ft above Earth – CBS News Tue, 23 Apr 2013 20:21:33 +0000 admin

SpaceX's Grasshopper taking off.

SpaceX’s Grasshopper taking off. / SpaceX

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NASA video displays 3 years of Sun images in 3 minutes – SlashGear Tue, 23 Apr 2013 20:21:32 +0000 admin

NASA‘s Solar Dynamics Observatory, more commonly known as SDO, has spent the last three years taking pictures of the sun, showing off its steady increase in activity as its latest 11-year cycle nears its peak. As part of the project, NASA has taken some of the images and compiled them into a single 3-minute video, which makes it easy to see the gradual increase in solar activity. You can check out the video after the jump.


The SDO started taking the pictures early in 2010, says NASA, snapping one image of the sun every 12 seconds, each shot being taken in 10 wavelengths. Each wavelength shows the sun in a different way, with four of them being featured in the second half of the video, which you can watch below. The video most prominently displays the sun in 171 Angstroms wavelength.

Although the SDO captured an image every 12 seconds, the video only features two images taken each day over the course of three years. Each image is shown for two frames, and the video has a frame rate of 29.7fps. As such, the video is only 3 minutes long, but makes it simple to note every 25-day rotation, as well as some other events, including a partial eclipse, a solar flare, and even the comet Lovejoy.

The solar images provide scientists with a constant stream of data to analyze, helping to solve questions and offer data on a variety of phenomenon. If you have an astute eye, you might notice that the sun seems to shrink and grow very slightly over the course of the video. NASA says this is because the spacecraft that took the images and the sun’s position are variable.

[via NASA]

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Human Stem Cells Restore Memory and Learning in Mice Brains – Science World Report Mon, 22 Apr 2013 15:04:40 +0000 admin


There’s a new breakthrough when it comes to restoring memory–at least in mice. Researchers have used human embryonic stem cells in the small mammals which allowed them to regain the ability to learn and remember.

The mice themselves were specially bred so that they wouldn’t reject transplants from other species. In order to simulate memory issues in the mice, the researchers intentionally damaged the part of the brain that is involved in both learning and memory–an area called the medial septum, which connects to the hippocampus by GABA and cholinergic neurons. They then cultured the embryonic stem cells in the lab, using chemicals that are known to promote development in nerve cells.

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The next step was actually transplanting the cells. They didn’t place these cells in the medial septum, though. Instead, the researchers placed the cells in the hippocampus, a vital memory center, located at the other end of the memory circuits. After this transplant, the cells slowly began to specialize and connect to the appropriate cells in the hippocampus in response to chemical directions from the brain.

This specialization didn’t come easily. The researchers had to ensure that the transplanted cells became neural cells–a critical part of the experiment.

“That means you are able to predict what the progeny will be, and for any future use in therapy, you reduce the chance of injecting stem cells that could form tumors,” said Su-Chun Zhang, the senior author, in a press release. “In many other transplant experiments, injecting early progenitor cells resulted in masses of cells–tumors. This didn’t happen in our case because the transplanted cells are pure and committed to a particular fate so that they do not generate anything else.”

In order to actually accomplish this cell direction, the researchers chemically directed the embryonic stem cells to begin differentiation into neural cells. They then injected these intermediate cells to prevent unwanted cell formation.

The most important step was yet to come, though. The researchers had to test to make sure that the implantation was actually effective. The mice were assessed with several common tests used to judge memory and and memory in the rodents. In the end, the researchers found that the mice scored significantly better than they had before the transplant.

The findings are a huge step forward when it comes to brain repair. Cell replacement with stem cells could potentially help people with memory-based conditions such as Alzheimer’s disease.

“Cholinergic neurons are involved in Alzheimer’s and Down syndrome, but GABA neurons are involved in many disorders, including schizophrenia, epilepsy, depression and addiction,” said Zhang in a press release.

Don’t get too excited, though. Stem-cell therapy is unlikely to be a cure-all. Psychiatric disorders are often complicated, and researchers aren’t always sure which part of the brain has gone “wrong.” That said, the research could be a vital step when it comes to better understanding what can be done to help those with memory disorders.

The findings are published in the journal Nature Biotechnology.

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Earth Day: Get Green With Google Doodles – Mashable – Mashable Mon, 22 Apr 2013 15:04:39 +0000 admin

Are you celebrating Earth Day? This year on April 22, more than one billion people “acknowledge the amazing planet we call home and take action to protect it.”

This year Earth Day is looking at “The Face of Climate Change” with a crowdsourced photo mosaic from individuals, organizations and companies across the world.

One company that always marks Earth Day is Google. Since 2001 it’s produced a specially-designed Doodle every year.

SEE ALSO: 13 Creative Google+ Cover Photo Hacks

To celebrate this special occasion, we’ve gathered all the Doodles. Take a look through our green gallery above. Let us know in the comments what you’re doing to mark Earth Day this year.

Image courtesy of Earth Day

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Cloning takes California’s ancient redwood trees abroad – USA Today – USA TODAY Mon, 22 Apr 2013 15:04:35 +0000 admin

A nonprofit group is shipping 18-inch clones of the towering trees to six countries to help fight climate change

COPEMISH, Mich. (AP) — California’s mighty redwoods are going international, cloned in an effort to promote reforestation and deal with climate change.

Although measuring just 18 inches (45 centimeters) tall, the laboratory-produced trees are genetic duplicates of three giants that were cut down in northern California more than a century ago. Remarkably, shoots still emerge from the stumps, including one known as the Fieldbrook Stump, which measures 35 feet (10.7 meters) in diameter. It’s believed to be about 4,000 years old. The tree was about 40 stories high before it was felled.

“This is a first step toward mass production,” said David Milarch, co-founder of Archangel Ancient Tree Archive, a nonprofit group spearheading the project, which is planting redwoods Monday (Earth Day) in Australia, New Zealand, Great Britain, Ireland, Canada, Germany and the U.S.

“We need to reforest the planet; it’s imperative. To do that, it just makes sense to use the largest, oldest, most iconic trees that ever lived,” Milarch said.

Milarch and his sons Jared and Jake, who have a family-owned nursery in Copemish, Michigan, became concerned about the condition of the world’s forests in the 1990s. They began crisscrossing the U.S. in search of “champion” trees that have lived hundreds or even thousands of years, convinced that superior genes enabled them to outlast others of their species. Scientific opinion varies on whether that’s true, with skeptics saying the survivors may simply have been lucky.

The Archangel leaders say they’re out to prove the doubters wrong. They’ve developed several methods of producing genetic copies from cuttings, including placing branch tips less than an inch long in baby food jars containing nutrients and hormones. The specimens are cultivated in labs until large enough to be planted.

In recent years, they focus has been on towering sequoias and redwoods, considered best suited to absorb massive volumes of carbon dioxide, the greenhouse gas primarily responsible for climate change.

“If we get enough of these trees out there, we’ll make a difference,” said Jared Milarch, the group’s executive director.

Archangel has an inventory of several thousand clones in various stages of growth that were taken from more than 70 redwoods and giant sequoias. NASA engineer Steve Craft, who helped arrange for David Milarch to address an agency gathering, said research shows that those species hold much more carbon than other varieties.

The challenge is to find places to put the trees, people to nurture them and money to continue the project, Jared Milarch said. The group is funded through donations and doesn’t charge for its clones.

“A lot of trees will be planted by a lot of groups on Arbor Day (April 26 in the United States), but 90 percent of them will die,” David Milarch said. “It’s a feel-good thing. You can’t plant trees and walk away and expect them to take care of themselves.”

The recipients of Archangel redwoods have pledged to care for them properly, he said. The first planting of about 250 took place in December on a ranch near Port Orford, Oregon. Others will be planted during Earth Day observances Monday at the College of Marin in Kentwood, Calif., and in parks and private estates in the other six countries.

“I know the trees will thrive here,” said Tom Burke, landscape manager at the College of Marin. “We’ve had redwoods in this area since God planted them.”

Copyright 2012 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

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Home » Sunnyside’s Dr. Bonnie Dunbar Inducted into the US Astronaut Hall of … – KAPP Mon, 22 Apr 2013 15:04:34 +0000 admin

Published Monday, April 22nd, 2013

<p>Bonnie Dunbar, Ph.D.</p>

Bonnie Dunbar, Ph.D.

Sunnyside Native and former NASA Astronaut Doctor Bonnie Dunbar is inducted into the US Astronaut Hall of Fame.

More than 30 legendary astronauts and space icons were present during Saturday’s star-studded ceremony at the Kennedy Space Center Visitor Complex.

Dunbar, who served as a shuttle mission specialist and payload commander, brings the number of space explorers enshrined in the Hall of Fame to 85.

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Chesapeake Bay’s Blue Crab Population Plummets: Cannibalism and Fish to … – Science World Report Mon, 22 Apr 2013 15:04:31 +0000 admin

Blue Crab

It turns out that Chesapeake Bay has something else to worry about aside from its underwater grasses. The bay’s blue crab population is at its lowest level in five years, according to Maryland officials. The drop in crabs has prompted tighter catch limits on the region’s iconic crustacean.

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The findings came after an annual winter survey of Maryland and Virginia waters, which found only 300 million crabs in total; that’s down by almost two-thirds from last year when Governor Martin O’Malley announced that the crabs had rebounded from a near population collapse in 2008. The recent announcement is a major setback for those who were working on rebuilding healthy population numbers.

After the near-collapse in 2008, Virginia and Maryland imposed catch limits on blue crabs and disallowed the catching of females. The results made fisheries optimistic; the population rebounded and in the winter of 2011 to 2012, the blue crabs were up by 66 percent from the 461 million in 2010.

Blue crabs are actually strongly linked to the underwater grasses and oyster beds of Chesapeake Bay. The oysters provide the crustaceans with nourishment while the grasses present it with shelter. Unfortunately, the spread of underwater grasses has declined drastically in recent years due to massive storms and excessively warm waters in 2010. In fact, researchers found that the grasses have dropped by as much as 21 percent in 2011.

Surprisingly, though, it turns out that the number of females needed to sustain the population is actually above the usual threshold. Instead, it’s the number of juvenile crabs that seem to have disappeared. The recent survey discovered that juveniles dropped by 80 percent since last year.

Fishing doesn’t seem to be the cause of this drop, either. Instead, an influx of crab-eating fish–red drum, in particular–may have precipitated the massive population decline. Another possibility is that many of the crabs are turning to cannibalism and are eating the younger and smaller crabs, according to the Baltimore Sun.

Currently, fisheries and officials are taking the drop of population numbers into account. It’s likely that the catch will be limited this year, which means less blue crab meat for the rest of us.

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