Obama Promises Faster Transition in Afghanistan

President Obama and Afghan President Hamid Karzai said today that most U.S. combat operations in Afghanistan would end this spring, signaling a quickening troop drawdown that will bring the decade-long war to a close at the end of 2014.

"Our troops will continue to fight alongside Afghans when needed, but let me say it as plainly as I can: Starting this spring, our troops will have a different mission -- training, advising, assisting Afghan forces," Obama announced at an East Room news conference in Washington.

"It will be a historic moment and another step toward full Afghan sovereignty, something I know that President Karzai cares deeply about, as do the Afghan people," he said.

Administration officials said Afghan forces were "exceeding initial expectations" in their capabilities. Afghan security forces are expected to lead 90 percent of security operations across the country in February.

"By the end of next year -- 2014 -- the transition will be complete," Obama said. "Afghans will have full responsibility for their security, and this war will come to a responsible end."

The rosy assessments belied the serious political, economic and security challenges that remain.

Left unanswered by Obama and Karzai: How many U.S. troops might stay after 2014; what their mission would be and whether they could be effective; and whether the forces would have immunity from prosecution in Afghan courts.

Charles Dharapak/AP Photo

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Obama said he was still reviewing recommendations from the Pentagon and will make an announcement in the coming weeks after penning an anticipated bilateral security agreement with Afghanistan. Karzai said the exact number would be up to the United States to decide.

Both leaders confirmed in a statement that the United States "does not seek permanent bases in Afghanistan."

They also agreed today to turn over battlefield combatants held by the U.S. military in Afghanistan to Afghan government control, which has been long-sought by Karzai.

Roughly 66,000 U.S. troops are serving in Afghanistan. The military has proposed keeping several thousand troops in the country after 2014 as advisers, trainers and logistical support for Afghan forces; the White House has said it remains open to pulling out all troops entirely.

Obama's visit with Karzai was the first face-to-face encounter since the November election and since last year's dramatic increase in so-called green-on-blue attacks, when U.S. and NATO soldiers have been killed by the Afghans they are training or working alongside.

There were 45 insider attacks in 2012 that resulted in 62 deaths among coalition forces, including 35 Americans. There has been one attack already in the first 11 days of 2013.

The White House summit included a private Oval Office meeting between Obama, Karzai and Vice President Joe Biden. The trio also attended a private lunch in the Old Family Dining Room.

Karzai Thursday attended meetings with Defense Secretary Leon Panetta and top military brass at the Pentagon, where he was afforded all the pomp and circumstance accorded a head of state: a 21-gun salute, and marching bands and honor guards from the Army, Navy, Air Force, Marines and Coast Guard.

Karzai's relationship with the United States has at times been a rocky one as he has sometimes made critical statements about the allied troop presence in his country. U.S. officials believe he has made those comments out of political expediency to improve his standing with Afghans and show his independence.

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Bibles used by King, Lincoln to be part of Obama’s second inauguration

Martin Luther King Jr. carried a black leather King James Bible on his journeys as a young pastor starting out in Montgomery, Ala. He turned to this “traveling Bible” for inspiration, his family says, as he fought for freedom and equality.

President Obama will put his hand over King’s well-worn Bible at his public swearing-in at the U.S. Capitol on Jan. 21, the holiday celebrating the birthday of the slain civil rights leader. King’s Bible will be stacked with the burgundy velvet and gilded Bible used by President Abraham Lincoln at his first inauguration.

Obama chose the Lincoln Bible for his inauguration in 2009, making him the first president to do so since it was initially used in 1861. President Harry S. Truman also used two Bibles, as did Dwight D. Eisenhower and Richard M. Nixon.

The announcement about the Bibles, to be made publicly Thursday, is part of the slow unspooling of inaugural details that fascinates lovers of ceremonial Americana.

Presidential inaugurations have become more filled with rites, and such decisions are especially weighty now at a time when the White House is aware that Americans are struggling to come together.

King’s family said in a statement that he would be “deeply moved” to see Obama use the traveling Bible on Martin Luther King Jr. Day, “and we hope it can be a source of strength for the President as he begins his second term.”

“With the Inauguration less than two weeks away, we join Americans across the country in embracing this opportunity to celebrate how far we have come, honor the legacy of Martin Luther King Jr. through service, and rededicate ourselves to the work ahead,” the statement added.

According to the Presidential Inaugural Committee, which organizes the swearing-in ceremony, King traveled with various books, including this Bible. “It was used for inspiration and preparing sermons and speeches, including during Dr. King’s time as pastor of Dexter Avenue Baptist Church” in Montgomery, the committee said in a statement.

Obama and Vice President Biden will be sworn in privately on Sunday, Jan. 20 — the date required by the Constitution. For that first ceremony, Obama will use the family Bible of his wife’s family. According to the inaugural committee, that Bible “was a gift from the First Lady’s father, Fraser Robinson III, to his mother, LaVaughn Delores Robinson, on Mother’s Day in 1958. Mrs. Robinson was the first African-American woman manager of a Moody Bible Institute’s bookstore.” That Bible was the only one Michelle Obama’s grandmother used after that, a committee statement said.

For both the private and then the Monday public ceremonies, Biden will be sworn in with a Bible that has been in his family since 1893: a five-inch-thick volume with a Celtic cross on the cover. He also used it for his swearings-in as a U.S. senator and in 2009 as vice president.

Some aspects of the inaugural ceremony have changed slightly over the decades. Having official prayers offered dates only to the 1930s, historians say. But presidents have used Bibles to be sworn in since George Washington, even though the Constitution does not require it. The Constitution also does not require the phrase “So help me God” at the end, but that has become standard, said Donald Ritchie, the historian of the U.S. Senate.

He also noted that the image of the president’s spouse holding the Bible dates only to Lady Bird Johnson doing so in 1965.

Chief justices of the Supreme Court now traditionally deliver the oath, but Ritchie said any federal official can do so.

Several non-Christian members of Congress have recently used other scriptures, including Rep. Keith Ellison, the first Muslim elected to Congress, in 2007. The Minnesota Democrat used a Koran owned by Thomas Jefferson.

Obama veered from tradition in one key aspect of the ceremony: He invited Myrlie Evers-Williams, widow of slain civil rights figure Medgar Evers, to deliver the invocation prayer. It will be the first time a woman, and a layperson rather than clergy, has done so.

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American Express cuts 5,400 jobs

American Express said Thursday it would lay off 8.5 per cent of its workforce in 2013, in an effort to contain operating expenses and adapt to customers moving to online and mobile platforms.

The bank said it would eliminate 5,400 jobs, though some of those will be offset by new positions, for a net cut of 4-6 per cent of the 63,500-strong workforce.

The layoffs will span different staff groups and businesses, both in the United States and its international operations, the company said.

The largest reductions will be in AmEx's travel businesses "which operate in an industry that is being fundamentally reinvented as a result of the digital revolution."

It said it took a US$400 million restructuring charge in its fourth quarter to December 31 to cover some of the severance costs of the layoffs.

The restructuring is "designed to contain future operating expenses, adapt parts of the business as more customers transact online or through mobile channels, and provide the resources for additional growth initiatives in the US and internationally," AmEx said.

Excluding the restructuring costs and other special items, the bank said its fourth-quarter net earnings came in at US$1.2 billion, the same as the year-earlier figure.

After the extra costs, net income was at US$637 million, or 56 cents a share, compared with US$1.01 a share for the fourth quarter of 2011.

"Maintaining our momentum in this environment will require us to evolve our business, embrace new technologies, become more efficient and generate resources to invest in the many growth opportunities we've identified," said chief executive Kenneth Chenault.

"For the next two years, our aim is to hold annual operating expense increases to less than three per cent.

"The overall restructuring program will put us in a better position as we seek to deliver strong results for shareholders and to maintain marketing and promotion investments at about nine per cent of revenues."

- AFP/jc

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Visit of Pak judicial commission will not be affected

NEW DELHI: Although the killing of two Indian soldiers by the Pakistan army has sparked widespread outrage, the incident will not affect the visit of a Pakistani judicial commission to India in connection with the 26/11 Mumbai terror attack case with home minister Sushilkumar Shinde seeing it as a "very positive step".

Shinde said the inclusion of Ujjwal Nikam, special prosecutor in the trial of Lashkar-e-Taiba gunman Ajmal Kasab in a team that visited Pakistan in December as an indicator of some positive movement.

Asked about the date of the visit of the Pakistani judicial commission for cross examination of four persons in connection with the 26/11 trial, Shinde said no date has been fixed yet but the government wants that the process should be completed soon.

"It (proposed visit of the panel) is a very positive step. The way they would be coming, we would also go ... We want this case to be concluded as early as possible," he said.

He said the team that had visited Pakistan last month had finalized the terms of reference of the judicial commission.

Asked whether infiltration into Jammu and Kashmir has been on the rise, Shinde said "infiltration has been going on" but Indian security forces were successful in eliminating many of the terrorists who entered in the recent past.

He said there was no information that Pakistan-based extremists were involved in Tuesday's killing of two Indian soldiers but some infiltrators could have been involved in some of the recent attacks on Indian soldiers.

The agreement on the second visit of the panel was finalized on December 25 in Islamabad following several rounds of discussions on complex technical and legal issues between a four-member visiting Indian delegation and Pakistani officials.

During its visit, the Indian team secured assurance from Pakistani authorities that the findings of the second judicial commission would not be summarily rejected by the anti- terrorism court that is conducting the trial of the seven LeT terrorists including the outfit's operational commander Zakiur Rehman Lakhvi.

The panel had visited Mumbai for the first time in March last year. But it was not allowed to cross examine the witnesses. It had then just recorded their statement and returned. Its findings were subsequently rejected by the anti-terrorism court in Rawalpindi as the panel's members were not allowed to cross-examine the Indian witnesses.

The witnesses are metropolitan magistrate RV Sawant Waghule, who recorded the confessional statement of hanged terrorist Ajmal Kasab, investigating officer Ramesh Mahale and two doctors from the state-run hospitals who had conducted autopsies of nine terrorists.

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How "Cheating" Slime Mold Escapes Death

Cheaters do prosper—at least if you're a slime mold, a new study says.

The slime mold Dictyostelium discoideum, found in most warm parts of the world, has an unusual life cycle. Most of the time Dicytostelium cells are "happy" single cells that hang out and eat bacteria, according to study leader Lorenzo Santorelli of the University of Oxford, who conducted the research while at Rice University and Baylor College of Medicine.

But sometimes, when food is scarce, different strains of Dictyostelium, including a mutated strain, form a mobile, multicellular organism called a "slug." This cluster then sprouts a stalk called a fruiting body, which produces spores that disperse into new slime molds. (Also see "Slime Has Memory but No Brain.")

For a slug to produce a stalk, however, nearly 20 percent of its cells must die—essentially sacrificing themselves to pass on their genes. (Get a genetics overview.) The remaining 80 percent live on and become spores.

Now, for the first time, Santorelli and colleagues have figured out the mechanism by which the mutated strain is able to survive in higher numbers than the others.

It suppresses normal cells from becoming spores, thereby forcing more of these cells to sacrifice themselves for the stalk and die. Meanwhile, more cells in the mutated strain become spores—and thus avoid dying as stalk cells. In other words, more than the "fair share" of cheater cells see another day.

Cheating Cells Surprisingly Healthy

To make the discovery, the team mixed the cheater strain with normal strains and observed that more cells in the cheater strain live on. (See "Smart Slime, Ovulating Strippers Among 2008 Ig Nobels.")

On one hand, this isn't all that surprising, Santorelli noted: "Cooperation is always under attack in any organism—trying to get something for [yourself], it's just nature."

But what is striking, he said, is that usually cheaters eventually cause the entire cooperative system to collapse. Not so in Dictyostelium—somehow it's evolved a way to keep everything running smoothly, said Santorelli, whose study was recently published in the journal BMC Evolutionary Biology.

What's more, cheaters are usually weaker than cooperative individuals. But not in Dictyostelium cheaters, which appear to be quite healthy.

Santorelli wants to find out how the cheater strain is so successful. And, just maybe, the lowly slime mold could unravel the evolutionary and genetic basis for cooperation, he added.

"Slime mold is an amazing organism."

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Jodi Arias: 'No Jury Will Convict Me' for Murder

The jury in the Jodi Arias murder trial watched a television interview today in which Arias said "no jury will convict me" for killing her ex-boyfriend, Travis Alexander.

Arias added that she could never imagine committing such a violent act as killing Alexander.

"I understand all the evidence is really compelling," she said in the interview. "In a nutshell, two people came in and killed Travis. I've never even shot a gun. That's heinous. I can't imagine slitting anyone's throat."

She went on to tell the interviewer, "No jury will convict me and you can mark my words on that. ... I am innocent."

Arias made the statements to the television show "Inside Edition" after she was indicted for murdering Alexander. Months later, she would confess to killing him in his Mesa, Ariz., home and say it was in self-defense.

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The tape was played on the fifth day of testimony in Arias' trial, in which police allege that she carried out the murder with such brutal force that she stabbed Alexander 27 times, slashed his throat from ear to ear, and shot him in the head.

Arias, now 32, has claimed Alexander was a controlling and abusive "sexual deviant" who she was forced to kill in self-defense.

She could face the death penalty if convicted of Alexander's murder.

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The defense petitioned the court to declare a mistrial at the end of testimony today, but the request was denied by Judge Sherry Stephens. Arias' attorneys claimed that testimony presented by Det. Esteban Flores about whether Arias shot Alexander first or at the end of the attack was different from his earlier testimony and, therefore, affected whether Arias was "especially cruel" during the killing -- but Stephens denied that it had any effect.

The jury also watched as dozens of photos of blood-spattered walls, flooring, stained carpets and blood smeared sink were explained in detail by a forensic analyst from the Mesa Police Department, who noted that on many of the stains water had been mixed with the blood and diluted it.

The prosecution has alleged that Arias tried to wash away the evidence of the killing with water.

Prosecutors spent much of today and Wednesday using Arias' recorded statements and other testimony to prove that she lied about her relationship with Alexander, where she was when Alexander was killed, and even where she worked as a bartender.

The testimony today suggested that Arias lied to her new boyfriend Ryan Burns about working at a bar called Margaritaville in her hometown of Yreka, Calif.

"Is there any restaurant in Yreka called Margaritaville? Has there ever been?" prosecutor Juan Martinez asked Nathaniel Mendes, a former detective with the Siskiyou County Sheriff's Office in California.

"No, sir," Mendes replied.

Mendes testified that Arias worked at a restaurant called Casa Ramos in Yreka, not a bar called Margaritaville, as she told Burns.

Mendes also went over receipts showing that Arias rented a car the day before she killed Alexander, and noted that she went to a rental outfit 90 miles from her hometown despite two businesses that rented cars in Yreka.

Arias told friends and investigators that she rented a car to go on a road trip to visit Burns, in West Jordan, Utah, on June 3, 2008. She showed up at Burns' house a day late with cuts on her hands, but told Burns that she got lost driving and that the cuts were from broken glass at her Margaritaville bartending job, according to Burns' testimony Wednesday.

The trail of receipts showed that Arias drove from California to Alexander's hometown of Mesa, Ariz., on Tuesday, June 4, 2008.

There, the pair had sex and took sexually graphic photos of one another, according to photographs and the opening statement of Arias' lawyer. Shortly after the tryst, Arias killed Alexander, both sides agree.

Burns testified that Arias never mentioned going to Alexander's house when she arrived at his home in Utah. He said he did not know that Arias and Alexander were still sexually involved, and that she told him they had broken up.

When she arrived at his home 24 hours after killing Alexander, she seemed "normal," he said. The pair kissed and cuddled, and went out with Burns' friends, where she laughed and made conversation.

Prosecutors have played recorded phone conversations between detectives and Arias in the weeks after Alexander's body was found. She could be heard apparently lying multiple times to investigators as they asked about the last time she spoke with Alexander and her trip to Utah.

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Hilda Solis resigns as labor secretary; some others in Cabinet to stay on

The reshuffling of President Obama’s Cabinet gained speed Wednesday when Labor Secretary Hilda Solis announced her resignation, but White House officials said three others, including Attorney General Eric Holder, would remain in their jobs.

Obama hailed Solis, who presided over a period of high unemployment, as “a tireless champion for working families” during “the worst economic downturn since the Great Depression.” In a statement Wednesday, the president said that “her efforts have helped train workers for the jobs of the future, protect workers’ health and safety and put millions of Americans back to work.”

Solis had been the first, and only, Hispanic American woman in a top Cabinet post. Her resignation, following the resignation of Environmental Protection Agency administrator Lisa Jackson and the withdrawal of Susan Rice from consideration for secretary of state, intensifies debate over whether there will be enough racial and gender diversity in Obama’s second-term Cabinet.

Obama has been restocking his cabinet ahead of his inauguration Jan. 20, this week unveiling nominees to lead the Defense Department and Central Intelligence Agency. On Thursday, he is expected to nominate White House Chief of Staff Jacob J. Lew to be Treasury secretary. Earlier, he named Sen. John F. Kerry (D-Mass.) as his choice for secretary of state. All four nominees are white men.

White House aides said, however, that Holder, Health and Human Services Secretary Kathleen Sebelius and Veterans Affairs Secretary Eric Shinseki would remain in their current posts. People familiar with Holder’s thinking said he does not expect to stay in office for Obama’s entire second term, and perhaps for as little as a few months.

Obama relied heavily on support from women and minority groups in the election, and some supporters have voiced concerns about a lack of women in top Cabinet jobs. But White House press secretary Jay Carney defended the president’s hiring record Wednesday, saying that Obama believes “diversity is important.”

“Women are well-represented here in the president’s senior staff,” Carney said. “These stories are in reaction to a couple of appointments.” He suggested waiting to see the “totality” of the president’s second-term Cabinet before rendering judgment on the diversity of his senior staff.

Solis has been widely expected to resign to run for office in Los Angeles, most likely for the powerful Los Angeles County Board of Supervisors.

In an interview at a Washington Post Live event in December, Solis recalled that a high school counselor “told me that I was not college material and that I should lower my sights and stay as secretary. Thirty years later, I can say my title is secretary of labor.”

Solis has defended the administration's record on job creation despite a stubbornly high unemployment rate that now stands at 7.8 percent nationwide and is far higher for African Americans and Latinos.

She has also come under criticism from some coal mine safety experts for failing to shake up the department’s Mine Safety and Health Administration or implement effective new regulations in the wake of the Upper Big Branch coal mine explosion in West Virginia, which killed 29 workers.

“What regulatory scheme has grown out of Upper Big Branch that has changed mine safety?” said J. Davitt McAteer, a former MSHA director and author of a report on the disaster. “The answer is nothing.” While acknowledging potential obstacles to changes in other parts of the government, McAteer said, “you’ve got to be able to put a package together and push it through, but that hasn’t happened.”

Nonetheless, news of her resignation prompted praise from leading Democrats and labor leaders.

AFL-CIO President Richard Trumka issued a statement saying that Solis, who came from a blue-collar family, had “brought urgently needed change” to the Labor Department. He said that, under her, the department “talks tough and acts tough on enforcement, workplace safety, wage and hour violations and so many other vital services.”

House Minority Leader Nancy Pelosi (D-Calif.) called her “an unflinching advocate for American workers.”

In a tweet Wednesday, Solis said: “We’ve accomplished much over the last 4 years, but none of it would have been possible without our greatest asset: America’s workers.”

Sari Horwitz and Al Kamen contributed to this report.

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US plays tough with Karzai on Afghan troops

WASHINGTON: US officials plan a mix of hardball negotiating and flattery during a visit by Afghan President Hamid Karzai as President Barack Obama decides how deeply to cut forces in America's longest war.

Karzai will be Obama's first foreign visitor of 2013, with a White House meeting on Friday and State Department dinner on Thursday. The Afghan leader met Wednesday with senators including Republican leader Mitch McConnell.

The talks come as the freshly re-elected Obama charts out plans to pull most of the 68,000 US troops out of Afghanistan. The United States and its allies have already agreed to withdraw combat troops by the end of 2014 but questions remain on a US training and security role after that.

Ben Rhodes, a deputy national security adviser, told reporters Tuesday that Obama sought to prevent Al-Qaeda's return to Afghanistan but would not rule out any ideas including the so-called zero option -- leaving no US troops at all.

Afghanistan watchers in Washington largely saw the hints as a strategy aimed at Karzai, who has had a tumultuous relationship with the Obama administration and is seen as wanting US troops to stay as long as possible.

James Dobbins, a former US diplomat involved in the establishment of Karzai's government in 2001, called the airing of the zero option "a tactical move designed to indicate to Karzai that he has less leverage in this negotiation than he might otherwise."

Dobbins, who considered a Taliban return to power in post-2014 Afghanistan to be possible but unlikely, said troop levels would be determined by how much the United States was willing to spend after more than 11 years of war.

"My view is it's a straight cost/risk ratio. The more you're prepared to pay, the lower your risk; the higher your risk tolerance, the less you can get away with," Dobbins, now an expert at the Rand Corp., said at the Atlantic Council think tank.

News reports have said that some administration officials favour as few as several thousand troops in Afghanistan. Obama's nominees as his next secretary of state and defence secretary, John Kerry and Chuck Hagel, are both seen as supportive of a wide-scale military drawdown.

Marvin Weinbaum of the Middle East Institute said he expected Karzai to press hardest during the White House meetings over what equipment, including air power, the United States would leave or provide Afghan forces.

"He doesn't want the US to pull out completely and he doesn't think the US wants to pull out completely. So that's the meeting point, but he wants to use that as leverage to extract as much as possible," Weinbaum said of Karzai.

Weinbaum said the visit was also aimed at preserving a friendly atmosphere with Karzai, who "is so thin-skinned, if you look at him the wrong way, he thinks you're plotting his demise."

"A lot of these meetings are just to try to keep the chemistry from getting too ugly," said Weinbaum, who believed the plentiful events for Karzai "improve the chances that maybe you can convince him that he's loved."

Tensions rose between the United States and Afghanistan after Karzai won presidential elections in 2009 despite widespread charges of irregularities.

The Obama administration has also pressed Karzai to curb corruption, considered by some US officials to be a major impediment to increasing the government's legitimacy in Afghan eyes.

Opinion polls for several years have shown that the US public is tired of the human and financial cost of the Afghanistan war, initially launched after the September 11, 2001, attacks on the United States. US forces killed Osama bin Laden, the attack's mastermind, in Pakistan in 2011.

But neoconservative analysts Fred and Kimberly Kagan, writing in The Wall Street Journal, said that leaving only a tiny US military presence would impede operations against Al-Qaeda and risk a renewal of ethnic civil war.

"Those who say that Afghanistan can't get any worse than it is today lack both imagination and any knowledge of the country's recent history," they wrote.

- AFP/jc

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Pakistani attackers took away soldier’s head as ‘trophy’

NEW DELHI: The fog of war is a reality even during peace time along the troubled Indo-Pak border. So it is not surprising that Tuesday's gruesome attack on Indian soldiers has slightly different narratives, according to who you speak to.

What is clear is that three soldiers of 13 Rajputana Rifles, the "Barasingha" battalion deployed with two others in the Mendhar sector, were together when they were attacked by the Pakistani intruders. The soldiers were close to the LoC, ahead of Indian fencing built several meters inside the LOC.

The intelligence establishment says the three were returning after manning through the night to an advance post, ahead of the fence, when they were ambushed. They were on their way to the company headquarters around 10.45am when the attack took place.

However, Army officials said the three were acting as "scouts" ahead of the seven-member "area domination patrol" when they were ambushed.

All, however, agree the two — Lance Naik Hemraj and ​Lance Naik Sudhakar Singh—were killed immediately. The Pakistanis beheaded Hemraj — and carried his head back across the border as a "trophy" — and were then were trying to severe Singh's head but failed. Probably, it was then that the other Indian troops opened fire.

The gun-battle lasted for over 30 minutes. The third soldier, who was injured but escaped a brutal death, is being treated at the military hospital in Udhampur.

The Pakistani attackers took away the personal weapons of both Hemraj and Singh. Some sources indicate there was even hand-to-hand engagement between the two sides, knife injuries on the dead are indicative of that.

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Embryonic Sharks Freeze to Avoid Detection

Jane J. Lee

Although shark pups are born with all the equipment they'll ever need to defend themselves and hunt down food, developing embryos still stuck in their egg cases are vulnerable to predators. But a new study finds that even these baby sharks can detect a potential predator, and play possum to avoid being eaten.

Every living thing gives off a weak electrical field. Sharks can sense this with a series of pores—called the ampullae of Lorenzini—on their heads and around their eyes, and some species rely on this electrosensory ability to find food buried in the seafloor. (See pictures of electroreceptive fish.)

Two previous studies on the spotted catshark (Scyliorhinus canicula) and the clearnose skate (Raja eglanteria)—a relative of sharks—found similar freezing behavior in their young. But new research by shark biologist and doctoral student Ryan Kempster at the University of Western Australia has given scientists a more thorough understanding of this behavior.

It all started because Kempster wanted to build a better shark repellent. Since he needed to know how sharks respond to electrical fields, Kempster decided to use embryos. "It's very hard to test this in the field because you need to get repeated responses," he said. And you can't always get the same shark to cooperate multiple times. "But we could use embryos because they're contained within an egg case."

Cloaking Themselves

So Kempster got his hands on 11 brownbanded bamboo shark (Chiloscyllium punctatum) embryos and tested their reactions to the simulated weak electrical field of a predator. (Popular pictures: Bamboo shark swallowed whole—by another shark.)

In a study published today in the journal PLoS One, Kempster and his colleagues report that all of the embryonic bamboo sharks, once they reached later stages of development, reacted to the electrical field by ceasing gill movements (essentially, holding their breath), curling their tails around their bodies, and freezing.

A bamboo shark embryo normally beats its tail to move fresh seawater in and out of its egg case. But that generates odor cues and small water currents that can give away its position. The beating of its gills as it breathes also generates an electrical field that predators can use to find it.

"So it cloaks itself," said neuroecologist Joseph Sisneros, at the University of Washington in Seattle, who was not involved in the study. "[The embryo] shuts down any odor cues, water movement, and its own electrical signal."

Sisneros, who conducted the previous clearnose skate work, is delighted to see that this shark species also reacts to external electrical fields and said it would be great to see whether this is something all shark, skate, and ray embryos do.

Marine biologist Stephen Kajiura, at Florida Atlantic University, is curious to know how well the simulated electrical fields compare to the bamboo shark's natural predators—the experimental field was on the higher end of the range normally given off.

"[But] they did a good job with [the study]," Kajiura said. "They certainly did a more thorough study than anyone else has done."

Electrifying Protection?

In addition to the freezing behavior he recorded in the bamboo shark embryos, Kempster found that the shark pups remembered the electrical field signal when it was presented again within 40 minutes and that they wouldn't respond as strongly to subsequent exposures as they did initially.

This is important for developing shark repellents, he said, since some of them use electrical fields to ward off the animals. "So if you were using a shark repellent, you would need to change the current over a 20- to 30-minute period so the shark doesn't get used to that field."

Kempster envisions using electrical fields to not only keep humans safe but to protect sharks as well. Shark populations have been on the decline for decades, due partly to ending up as bycatch, or accidental catches, in the nets and on the longlines of fishers targeting other animals.

A 2006 study estimated that as much as 70 percent of landings, by weight, in the Spanish surface longline fleet were sharks, while a 2007 report found that eight million sharks are hooked each year off the coast of southern Africa. (Read about the global fisheries crisis in National Geographic magazine.)

"If we can produce something effective, it could be used in the fishing industry to reduce shark bycatch," Kempster said. "In [America] at the moment, they're doing quite a lot of work trying to produce electromagnetic fish hooks." The eventual hope is that if these hooks repel the sharks, they won't accidentally end up on longlines.

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