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Genomic Study Traces Roma to Northern India
By SINDYA N. BHANOO, The New York Times, December 10, 2012

The Roma people of Europe, often called Gypsies, are long thought to have originated in India because of similarities between Roma and Indian languages. But historical records are scanty.

Now a wide-ranging genomic study appears to confirm that the Roma came from a single group that left northwestern India about 1,500 years ago.

“Some genetic studies have also pointed to India before, but it was not clear what part of India,” said an author of the study, David Comas, an evolutionary biologist at Pompeu Fabra University in Barcelona.

Dr. Comas led the study with Manfred Kayser from Erasmus University Rotterdam in the Netherlands. They and other colleagues report their findings in a recent issue of Current Biology.



The researchers studied 800,000 genetic markers in more than 150 Roma from 13 groups and compared them with people from other ethnic groups. Dr. Comas and his colleagues found that the Roma are also genetically similar to other Europeans.

“Fifteen hundred years ago these people went to the Balkans and then spread all over Europe,” Dr. Comas said. “And they have mixed with Europeans during different periods throughout.”

At about 11 million, the Roma are Europe’s largest minority, and are frequently the subject of political dispute in the European Union. The marginalized group is still nomadic, often building illegal camps.

“This is an example of one minority that has been ignored in most genetic studies,” Dr. Comas said. “What we have now is an idea of the origins and genetic structure of this population.”





How to Control an Army of Zombies
By CARL ZIMMER, The New York Times, December 5, 2012

In the rain forests of Costa Rica lives Anelosimus octavius, a species of spider that sometimes displays a strange and ghoulish habit.

From time to time these spiders abandon their own webs and build radically different ones, a home not for the spider but for a parasitic wasp that has been living inside it. Then the spider dies — a zombie architect, its brain hijacked by its parasitic invader — and out of its body crawls the wasp’s larva, which has been growing inside it all this time.

The current issue of the prestigious Journal of Experimental Biology is entirely dedicated to such examples of zombies in nature. They are far from rare. Viruses, fungi, protozoans, wasps, tapeworms and a vast number of other parasites can control the brains of their hosts and get them to do their bidding. But only recently have scientists started to work out the sophisticated biochemistry that the parasites use.



“The knowledge that parasites can manipulate their hosts is old. The new part is how they do it,” said Shelley Adamo of Dalhousie University in Nova Scotia, a co-editor of the new issue. “The last 5 to 10 years have really been exciting.”

In the case of the Costa Rican spider, the new web is splendidly suited to its wasp invader. Unlike the spider’s normal web, mostly a tangle of threads, this one has a platform topped by a thick sheet that protects it from the rain. The wasp larva crawls to the edge of the platform and spins a cocoon that hangs down through an opening that the spider has kindly provided for the parasite.

To manipulate the spiders, the wasp must have genes that produce proteins that alter spider behavior, and in some species, scientists are now pinpointing this type of gene. Such is the case with the baculovirus, a virus sprinkled liberally on leaves in forests and gardens. (The cabbage in a serving of coleslaw carries 100 million baculoviruses.)

Human diners need not worry, because the virus is harmful only to caterpillars of insect species, like gypsy moths. When a caterpillar bites a baculovirus-laden leaf, the parasite invades its cells and begins to replicate, sending the command “climb high.” The hosts end up high in trees, which has earned this infection the name treetop disease. The bodies of the caterpillars then dissolve, releasing a rain of viruses on unsuspecting hosts below.

David P. Hughes of Penn State University and his colleagues have found that a single gene, known as egt, is responsible for driving the caterpillars up trees. The gene encodes an enzyme. When the enzyme is released inside the caterpillar, it destroys a hormone that signals a caterpillar to stop feeding and molt.

Dr. Hughes suspects that the virus goads the caterpillar into a feeding frenzy. Normally, gypsy moth caterpillars come out at night to feed and then return to crevices near the bottom of trees to hide from predators. The zombie caterpillars, on the other hand, cannot stop searching for food.

“The infected individuals are out there, just eating and eating,” Dr. Hughes said. “They’re stuck in a loop.”

Other parasites manipulate their hosts by altering the neurotransmitters in their brains. This kind of psychopharmacology is how thorny-headed worms send their hosts to their doom.

Their host is a shrimplike crustacean called a gammarid. Gammarids, which live in ponds, typically respond to disturbances by diving down into the mud. An infected gammarid, by contrast, races up to the surface of the pond. It then scoots across the water until it finds a stem, a rock or some other object it can cling to.

The gammarid’s odd swimming behavior allows the parasite to take the next step in its life cycle. Unlike baculoviruses, which go from caterpillar to caterpillar, thorny-headed worms need to live in two species: a gammarid and then a bird. Hiding in the pond mud keeps a gammarid safe from predators. By forcing it to swim to the surface, the thorny-headed worm makes it an easy target.

Simone Helluy of Wellesley College studies this suicidal reversal. Her research indicates that the parasites manipulate the gammarid’s brain through its immune system.

The invader provokes a strong response from the gammarid’s immune cells, which unleash chemicals to kill the parasite. But the parasite fends off these attacks, and the host’s immune system instead produces an inflammation that infiltrates its own brain. There, it disrupts the brain’s chemistry — in particular, causing it to produce copious amounts of the neurotransmitter serotonin.

Serotonin influences how neurons transmit signals. Dr. Helluy proposes that the rush of serotonin triggered by the thorny-headed worms corrupts the signals traveling from the eyes to the brain. Normally, an escape reflex causes the gammarid to be attracted to the darkness at the bottom of its pond. Thorny-headed worms may cause their host to perceive sunlight as darkness, and thus swim up instead of down.

Whether humans are susceptible to this sort of zombie invasion is less clear. It is challenging enough to figure out how parasites manipulate invertebrates, which have a few hundred thousand neurons in their nervous systems. Vertebrates, including humans, have millions or billions of neurons, and so scientists have made fewer advances in studying their zombification.

Most of the research on vertebrate zombies has been carried on a single-celled parasite, Toxoplasma gondii. Like thorny-headed worms, it moves between predators and their prey. Toxoplasma reproduces in the guts of cats, which shed it in their feces.

Mammals and birds can pick up the parasite, which invade their brain cells and form cysts. When cats eat these infected animals, Toxoplasma completes its cycle. Scientists have found that Toxoplasma-infected rats lose their fear of cat odor — potentially making them easier prey to catch.

Glenn McConkey of the University of Leeds and his colleagues have found a possible explanation for how Toxoplasma wreaks this change. It produces an enzyme that speeds the production of the neurotransmitter dopamine, which influences mammals’ motivation and how they value rewards. Adding extra dopamine might make Toxoplasma’s hosts more curious and less fearful.

But Ajai Vyas of Nanyang Technological University in Singapore has found evidence that Toxoplasma simultaneously manipulates its hosts in other ways. Infected male rats, he found, make extra testosterone. This change makes the males more attractive to females, and when they mate the males spread the parasite to females.

By causing male rats to make more testosterone, Toxoplasma may do more than spread itself to other rats. Testosterone also tamps down fear. The infected rats may thus become even less concerned when they pick up the scent of a cat.

This research could potentially provide important clues about human behavior. In the case of Toxoplasma, for example, humans can become hosts if they handle contaminated cat litter or eat parasite-laden meat. Some studies have linked Toxoplasma infection with subtle changes in personality, as well as with a higher risk of schizophrenia.

Dr. Adamo, the co-editor of the journal’s new issue, thinks this new science of “neuroparasitology” can offer inspiration to pharmaceutical companies that are struggling to find effective drugs for mental disorders. “A number of the big companies have given up on their neuroscience labs,” she said. “Maybe the parasites can teach us something.”

She points out that the way parasites manipulate brains is profoundly different from drugs like Prozac. “The way that a parasite goes about changing behavior is not the way a neurobiologist would do it,” she said.

A typical drug focuses on just one type of molecule in the brain. Parasites, on the other hand, often launch a much broader attack that still manages to cause a specific change in their host. “Perhaps tweaking several systems simultaneously might give better results than trying to hit one particular system with a sledgehammer,” Dr. Adamo said.

But she added that she and other parasitologists barely understand those zombifying tweaks. “All we know now,” she said, “is they have their own ways.”





Divining the Weather, With Methods Old and New
By DAN BARRY, The New York Times, December 9, 2012

In these times of upset and uncertainty, comfort comes in knowing that dental floss can cut a dense cheesecake more cleanly than any knife. That cloves of garlic will send ants scurrying. That a cow requires at least 15 pounds of hay per day. That the state bird of South Dakota is the ring-necked pheasant.

For the 217th consecutive year, useful facts and tips like these have been assembled in J. Gruber’s Hagerstown Town and Country Almanack, a deceptively slim volume that is available to farmers, merchants and all good citizens — especially those residing in the Middle Atlantic States — at the nominal cost of $4.99.

Contained within its 82 pages is the accumulated wisdom of many generations of farmers who lived and worked according to the arc of the sun and the pull of the moon. This means that in addition to reporting that our nation’s fifth vice president was Elbridge Gerry and that the gift of a daffodil represents unrequited love, Gruber’s Almanack also provides “conjecture of the weather and other astronomical information.”

For example, if you want to know what weather to expect in New England next Thanksgiving Day, the almanac offers an answer with a better-than-even shot at accuracy: “Snow, heavy south.”

This is the educated guess of Bill O’Toole, 70, a retired college math professor who, for more than four decades, has served as the almanac’s seventh prognosticator — or conjecturer, or calculator — a line of work that began in 1797 with a star-savvy blacksmith. Mr. O’Toole is tall and bearded, with large eyes that convey wonder in all things, and a business card that declares in black and white his gray-area profession.

Working from desk space carved out of the book clutter of a brick row house here in Emmitsburg, about a mile south of the Pennsylvania line, Mr. O’Toole endeavors to divine the weather as much as 18 months in advance. He does so with a conjurer’s brew of age-old wisdom and 21st-century technology that includes a range of tools, from a software program of astronomical data produced by the United States Naval Observatory to the meticulous tracking — through some 30 computer programs he has written — of all things lunar.



The moon matters, Mr. O’Toole says, as people who work the land discovered long ago. “They noticed a trend,” he says. “When the moon changed phase close to midnight, the weather over the next lunar week, between six and nine days, would be fair, agreeable, calm. But it was just the opposite if it occurred close to noon: snowy, rainy, stormy, disagreeable.”

After completing his calculations, Mr. O’Toole charts his predictions on postcard-size weather maps of the continental United States, drawing a map for every week. Here, then, a test: Did the prognosticator foretell Sandy, the fall’s calamitous superstorm?

He points to a blue-ink swirl that he drew on one of those small maps. In June 2011. “Tropical storm from Atlantic,” the Almanack predicted — somewhat prematurely, it turned out. “I was off by a week and a few days,” he says. “Not too bad, considering this was done 16 months earlier.”

Mr. O’Toole ignores the occasional charge of quackery. He says that a person could predict the weather 25 percent of the time by simply throwing darts at a board, but that he shoots for better than 50 percent. And, in the annual “Conjecturer’s Column” that he writes for the almanac, he is nothing if not candid about his performance.

“Daily forecasts for the mid-Atlantic region were correct 55.1 percent of the time, slightly below last year’s 59.3 percent, which was the best in recent years,” Mr. O’Toole wrote in the current almanac. “The worst month for daily forecasts was October at 38.7 percent; the best was May, clocking in at 72.6 percent.”

Mr. O’Toole grew up in nearby Waynesboro, Pa. His father, William, was a toolmaker and sales representative, his mother, Dora, a homemaker and parish secretary who had grown up on a dairy farm. After she died at 91 last year, Mr. O’Toole found a diary in which his mother had faithfully recorded the weather every day for nearly 70 years.

High 76 degrees; rain; bright moonlit night...

“A deeply ingrained tradition among farmers,” he explained. A small way of trying to make sense of the natural world by those so grounded in it.

Mr. O’Toole was a boy so drawn to the moon and the stars that in high school he helped to establish an amateur astronomy club. After flirting with the idea of a career in astronomy, he graduated from Mount St. Mary’s University here, and promptly joined its math department as a teacher.

Then one day in 1969, he says, he received a call from “out of the blue” (a hoary expression that refers to the sky). It was the business manager of Gruber’s Almanack, and he wanted to know: Are you familiar with our publication?

Oh, yes.

Originally published in German, then German and English, then only in English when German became a dead-to-me language during World War I, the Gruber Almanack was as much a part of the local universe as Jupiter and Saturn. You’d punch a hole in the top left corner, hang it on a string, and consult it for — well, as the almanac puts it:

“The rising, setting, and Eclipses of the Sun and Moon; the phases, places, and southing of the Moon; the aspects of the planets; the rising, setting, and southing of the most conspicuous planets and fixed stars; the equation of time; with a variety of useful and entertaining matter, anecdotes, &c., &c.”

The business manager went on to explain that the almanac’s sixth prognosticator had passed away, and it was in need of its seventh. Was Mr. O’Toole interested?

Oh, yes.

He inherited his predecessor’s charts and notes and, before long, was using the lunar cycle and other variables to recommend the best days to plant, to weed, to harvest — even to go fishing (May 30 next year is good, for example, but May 31 is better).

The almanac has been passed on through the generations within the same family. These days it is owned and produced by three men driven more by loyalty than by money: Mr. O’Toole, a retired professor, is the prognosticator; Jerry Spessard, 63, a retired insurance agent and part-time inventor, is the longtime business manager; and Charles W. Fisher Jr., 63, a retired sales executive, is the editor and great-great-great-great-great-grandson of Johann Gruber.

Over the years, circulation has waxed and waned — it now is about 85,000 — but the readership remains fully engaged. Mr. Spessard often receives calls about sweet recollections of a grandmother’s reliance on the almanac, as well as angry complaints about a typographical error that might disrupt the spin of the earth.

But the earth continues to spin, and J. Gruber’s Hagerstown Town and Country Almanack continues to advise and to console. Dental floss can also be used as an emergency shoelace. The state flower of Maryland is the black-eyed Susan. And if you plan to be in the mid-Atlantic next Memorial Day, the prognosticator suggests that you might want to pack an umbrella.





Bid to Preserve Manhattan Project Sites in a Park Stirs Debate
By WILLIAM J. BROAD, The New York Times, December 3, 2012

A plan now before Congress would create a national park spread over three states to protect the aging remnants of the atomic bomb project from World War II, including an isolated cabin where grim findings threw the secretive effort into a panic.

Scientists used the remote cabin in the seclusion of Los Alamos, N.M., as the administrative base for a critical experiment to see if plutonium could be used to fuel the bomb. Early in 1944, sensitive measurements unexpectedly showed that the silvery metal underwent a high rate of spontaneous fission — a natural process of atoms splitting in two.

That meant the project’s design for a plutonium bomb would fail. J. Robert Oppenheimer, the project’s scientific head, was so dismayed that he considered resigning.

But he and his colleagues pressed ahead with a new design. On July 16, 1945, the world’s first atom bomb — a lump of plutonium at its core — illuminated the darkness of the central New Mexican desert with a flash of light brighter than the sun.

The plan for a Manhattan Project National Historical Park would preserve that log cabin and hundreds of other buildings and artifacts scattered across New Mexico, Washington and Tennessee — among them the rustic Los Alamos home of Dr. Oppenheimer and his wife, Kitty, and a large Quonset hut, also in New Mexico, where scientists assembled components for the plutonium bomb dropped on Japan.

“It’s a way to help educate the next generation,” said Cynthia C. Kelly, president of the Atomic Heritage Foundation, a private group in Washington that helped develop the preservation plan.



Jonathan B. Jarvis, director of the National Park Service, said the narrative of the bomb’s creation deserved a wide audience.

“There is no better place to tell a story than where it happened,” Mr. Jarvis said in a statement. “The National Park Service will be proud to interpret these Manhattan Project sites and unlock their stories in the years ahead.”

But critics have faulted the plan as celebrating a weapon of mass destruction, and have argued that the government should avoid that kind of advocacy.

Historians and federal agencies reply that preservation does not imply moral endorsement, and that the remains of so monumental a project should be saved as a way to encourage comprehension and public discussion.

Supporters of the atomic park are pressing for a vote on the measure in the expiring 112th Congress. The House, influenced by the critics, rejected the plan in September, and advocates are re-engaging members with new arguments in an effort to tip the balance of opinion in their favor.

“Both the House and Senate had hearings,” Ms. Kelly said in an interview. “We’re guardedly optimistic.”

The bills are sponsored by a bipartisan group of 10 lawmakers, mainly from the three states, led in the Senate by Jeff Bingaman of New Mexico, a Democrat, and in the House of Representatives by Doc Hastings of Washington, a Republican.

The plan has been in development for more than a decade. It began when the federal Energy Department — a descendant of the Manhattan Project that owns many of the sites — asked for guidance from the government’s Advisory Council on Historic Preservation.

In 2001, the council’s panel of distinguished experts recommended that the sites be established “as a collective unit administered for preservation, commemoration, and public interpretation in cooperation with the National Park Service.”

In 2004, Congress directed the secretary of the interior to study the park’s feasibility, in consultation with the secretary of energy. Last year, Ken Salazar, the interior secretary, wrote to Congress recommending its establishment.

He called the bomb’s development “one of the most transformative events in our nation’s history,” noting that it ushered in the atomic age, changed the international role of the United States and helped set the stage for the cold war.

Supporters of the park argue that preserving and managing the atomic sites is Washington’s least expensive option. Five years of National Park Service care, they say, would cost $21 million; demolishing the buildings and atomic sites would run to $200 million.

Ms. Kelly, of the Atomic Heritage Foundation, said the overall goal was commemoration, not celebration. She argued that even regrettable aspects of history — like the American Indian massacres and Civil War battles — deserved site preservation and cultural remembrance.

“This is a major chapter of American and world history,” she said. “We should preserve what’s left.”








‘Famous’ Wolf Is Killed Outside Yellowstone
By NATE SCHWEBER, The New York Times, December 8, 2012

Yellowstone National Park’s best-known wolf, beloved by many tourists and valued by scientists who tracked its movements, was shot and killed on Thursday outside the park’s boundaries, Wyoming wildlife officials reported.

The wolf, known as 832F to researchers, was the alpha female of the park’s highly visible Lamar Canyon pack and had become so well known that some wildlife watchers referred to her as a “rock star.” The animal had been a tourist favorite for most of the past six years.

The wolf was fitted with a $4,000 collar with GPS tracking technology, which is being returned, said Daniel Stahler, a project director for Yellowstone’s wolf program. Based on data from the wolf’s collar, researchers knew that her pack rarely ventured outside the park, and then only for brief periods, Dr. Stahler said.

This year’s hunting season in the northern Rockies has been especially controversial because of the high numbers of popular wolves and wolves fitted with research collars that have been killed just outside Yellowstone in Idaho, Montana and Wyoming.



Wolf hunts, sanctioned by recent federal and state rules applying to the northern Rockies, have been fiercely debated in the region. The wolf population has rebounded since they were reintroduced in the mid-1990s to counter their extirpation a few years earlier.

Many ranchers and hunters say the wolf hunts are a reasonable way to reduce attacks on livestock and protect big game populations.

This fall, the first wolf hunts in decades were authorized in Wyoming. The wolf killed last week was the eighth collared by researchers that was shot this year after leaving the park’s boundary.

The deaths have dismayed scientists who track wolves to study their habits, population spread and threats to their survival. Still, some found 832F’s death to be particularly disheartening.

“She is the most famous wolf in the world,” said Jimmy Jones, a wildlife photographer who lives in Los Angeles and whose portrait of 832F appears in the current issue of the magazine American Scientist.

Wildlife advocates say that the wolf populations are not large enough to withstand state-sanctioned harvests and that the animals attract tourist money. Yellowstone’s scenic Lamar Valley has been one of the most reliable places to view wolves in the northern Rockies, and it attracts scores of visitors every year.

Date: 2012-12-11 05:17 pm (UTC)
From: [identity profile] alexeye.livejournal.com
our guide told us about the zombie spiders when we were on a NIGHT HIKE in monteverde. right around when we saw the tarantula and the pit viper. i am shocked i slept at all the rest of that trip.

Date: 2012-12-13 02:34 pm (UTC)
From: [identity profile] brdgt.livejournal.com
Some good friends of ours are in Thailand for the year - they say they focus on keeping the bed free of spiders and bugs and lizards and give up on the rest of the house...

Date: 2012-12-13 05:49 am (UTC)
From: [identity profile] lindaquelinda.livejournal.com
dammit. that sucks about the wolves.

Date: 2012-12-13 02:34 pm (UTC)
From: [identity profile] brdgt.livejournal.com
I know :( I saw a great documentary that included that particular wolf earlier this year.

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