Pictures: Civil War Shipwreck Revealed by Sonar

Photograph by Jesse Cancelmo

A fishing net, likely only decades old, drapes over machinery that once connected the Hatteras' pistons to its paddle wheels, said Delgado.

From archived documents, the NOAA archaeologist learned that Blake, the ship's commander, surrendered as his ship was sinking. "It was listing to port, [or the left]," Delgado said. The Alabama took the wounded and the rest of the crew and put them in irons.

The officers were allowed to keep their swords and wander the deck as long as they promised not to lead an uprising against the Alabama's crew, he added.

From there, the Alabama dropped off their captives in Jamaica, leaving them to make their own way back to the U.S.

Delgado wants to dig even further into the crew of the Hatteras. He'd like see if members of the public recognize any of the names on his list of crew members and can give him background on the men.

"That's why I do archaeology," he said.

(Read about other Civil War battlefields in National Geographic magazine.)

Published January 11, 2013

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CDC: Flu Outbreak Could Be Waning

The flu season appears to be waning in some parts of the country, but that doesn't mean it won't make a comeback in the next few weeks, according to the Centers for Disease Control and Prevention.

Five fewer states reported high flu activity levels in the first week of January than the 29 that reported high activity levels in the last week of December, according to the CDC's weekly flu report. This week, 24 states reported high illness levels, 16 reported moderate levels, five reported low levels and one reported minimal levels, suggesting that the flu season peaked in the last week of December.

"It may be decreasing in some areas, but that's hard to predict," CDC Director Dr. Thomas Frieden said in a Friday morning teleconference. "Trends only in the next week or two will show whether we have in fact crossed the peak."

The flu season usually peaks in February or March, not December, said Dr. Jon Abramson, who specializes in pediatric infectious diseases at Wake Forest Baptist Health in North Carolina. He said the season started early with a dominant H3N2 strain, which was last seen a decade ago, in 2002-03. That year, the flu season also ended early.

Click here to see how this flu season stacks up against other years.

Cheryl Evans/The Arizona Republic/AP Photo

Increasing Flu Cases: Best Measures to Ensure Your Family's Health Watch Video

Because of the holiday season, Frieden said the data may have been skewed.

For instance, Connecticut appeared to be having a lighter flu season than other northeastern states at the end of December, but the state said it could have been a result of college winter break. College student health centers account for a large percentage of flu reports in Connecticut, but they've been closed since the fall semester ended, said William Gerrish, a spokesman for the state's department of public health.

The flu season arrived about a month early this year in parts of the South and the East, but it may only just be starting to take hold of states in the West, Frieden said. California is still showing "minimal" flu on the CDC's map, but that doesn't mean it will stay that way.

Click here to read about how flu has little to do with cold weather.

"It's not surprising. Influenza ebbs and flows during the flu season," Frieden said. "The only thing predictable about the flu is that it is unpredictable."

Dr. William Schaffner, chair of preventive medicine at Vanderbilt University Medical Center in Nashville, Tenn., said he was expecting California's seeming good luck with the flu to be over this week.

"Flu is fickle, we say," Schaffner said. "Influenza can be spotty. It can be more severe in one community than another for reasons incompletely understood."

Early CDC estimates indicate that this year's flu vaccine is 62 percent effective, meaning people who have been vaccinated are 62 percent less likely to need to see a doctor for flu treatment, Frieden said.

Although the shot has been generally believed to be more effective for children than adults, there's not enough data this year to draw conclusions yet.

"The flu vaccine is far from perfect, but it's still by far the best tool we have to prevent flu," Frieden said, adding that most of the 130 million vaccine doses have already been administered. "We're hearing of shortages of the vaccine, so if you haven't been vaccinated and want to be, it's better late than never."

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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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BJP's Hindutva forces back in limelight

LUCKNOW: It was in late 1990, after the then chief minister Mulayam Singh Yadav ordered firing on unarmed Kar Sevaks leaving several dead and subsequently leading to Hindu outrage across the state that Kalyan Singh came up as a prominent discovery on Hindutva front. It was Bharatiya Janata Party's pan-Hindu outreach initiative which led Singh, belonging to the backward caste of Lodhs, ride the crest of Hindutva wave.

After being in and out of the party twice in the past, Kalyan already planning to make a third time entry in BJP, might put the party's shunned ideology at centre stage.

After remaining as chief minister in the BJP government twice -- 1991-1992 and 1997-1999, Kalyan left the party for the first time in December 1999 and returned again in January, 2004 before the Lok Sabha elections. He contested the 2004 Lok Sabha elections on the BJP ticket from Bulandshahar. Again before the Lok Sabha election of 2009, he left BJP and contested election from Etah Lok Sabha seat as an independent and subsequently won it.

Cut to 2012:

BJP's poor performance and Kalyan Singh' failure to present his own creation -- Jan Kranti Party, as a force to reckon with in 2012 Assembly election brought both of them closer, while Samajwadi Party-led by Mulayam's son Akhilesh Yadav won the election with majority.

Though third rejoining likely in over a decade, Kalyan's re-entry in BJP, now expected anytime, political pundits feel could be an attempt to repeat 1991 and 1998 history partially if not in totality. But, what can be for sure said is that the saffron outfit is on way to make yet another bid to revive hindutva, feel political experts.

The effort gains prominence with subsequent developments which have taken place in the state BJP in the past a few months.

The indicators:

Giving credence to the strategy is the debut made by firebrand sanyasin Uma Bharti in UP politics winning Charkhari assembly seat, rare presence of torch-bearers of hindutva Gorakhpur MP Yogi Adityanath and Pilibhit MP Varun Gandhi at party's state council meeting and unanimous election of Laxmikant Bajpayi, a known hardliner, as state BJP chief.

Former chief minister of Madhya Pradesh Uma Bharti, who is known for her firebrand image, rejoined BJP after a hiatus of a few years, has made a comeback in mainstream politics, for the first time from Uttar Pradesh's Charkhari. She won the seat in UP assembly election this year.

Besides, torch-bearers of hindutva including Pilibhit MP Varun Gandhi and Gorakhpur MP Yogi Adityanath were among a few, who have also hogged the limelight at the party's state council meeting held at erstwhile Capitol picture hall on December 2.

While the Rashtriya Swayemsewak Sangh (RSS)-backed Gorakhpur MP Yogi Adityanath is said to have made one of his first visit at the BJP's state council meeting. Yogi while talking to TOI had admitted that it was his first visit to the state BJP office. About his presence, the firebrand MP and torch-bearer of Hindutva said that even after his busy schedule in Gorakhpur, he had come to express support to newly-elected state BJP chief Laxmikant Bajpayi.

Both Yogi and Gandhi had remained out of sight for different reasons during UP Assembly elections in March 2012 clearly indicating differences among senior party leaders.

Last but not the least, the unanimous election of Laxmikant Bajpayi, known for his hardliner image, for full three-year term as state BJP chief.

With past political experiences proving that any communal simmering in the state has benefitted both 'Mullah' Mulayam's (called by Sadhvi Ritambhara after 1990 firing on kar sevaks) Samajwadi Party and Bharatiya Janata Party on politics of polarisation, around a dozen communal tensions have taken place in the state since Samajwadi Party came to power in March this year.

This has given opportunity to BJP to take on Samajwadi Party government in the state. While on the one hand, BJP leaders are now lambasting Akhilesh-led SP government for adopting Muslim appeasement policy, on the other hand they have questioned the state government's inability to contain communal tensions especially in Faizabad, Bareilly, Mathura, Ghaziabad etc.

The BJP has now decided to hold a Hahakar Rally on December 15 at Meerut on law and order issue and even presented reports of their fact-finding team on clashes in Mathura, Banda, and Sultanpur on Wednesday itself. The BJP state chief Laxmikant Bajpayi also demanded to the chief minister to set up a probe into a dozen communal clashes that have taken place in the last over five months by special investigation agency.A planned revival of Hindutva, it seems!

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Google and Twitter Help Track Influenza Outbreaks

This flu season could be the longest and worst in years. So far 18 children have died from flu-related symptoms, and 2,257 people have been hospitalized.

Yesterday Boston Mayor Thomas Menino declared a citywide public health emergency, with roughly 700 confirmed flu cases—ten times the number the city saw last year.

"It arrived five weeks early, and it's shaping up to be a pretty bad flu season," said Lyn Finelli, who heads the Influenza Outbreak Response Team at the Centers for Disease Control and Prevention (CDC).

Boston isn't alone. According to the CDC, 41 states have reported widespread influenza activity, and in the last week of 2012, 5.6 percent of doctor's office visits across the country were for influenza-like illnesses. The severity likely stems from this year's predominant virus: H3N2, a strain known to severely affect children and the elderly. Finelli notes that the 2003-2004 flu season, also dominated by H3N2, produced similar numbers. (See "Are You Prepped? The Influenza Roundup.")

In tracking the flu, physicians and public health officials have a host of new surveillance tools at their disposal thanks to crowdsourcing and social media. Such tools let them get a sense of the flu's reach in real time rather than wait weeks for doctor's offices and state health departments to report in.

Pulling data from online sources "is no different than getting information on over-the-counter medication or thermometer purchases [to track against an outbreak]," said Philip Polgreen, an epidemiologist at the University of Iowa.

The most successful of these endeavors, Google Flu Trends, analyzes flu-related Internet search terms like "flu symptoms" or "flu medication" to estimate flu activity in different areas. It tracks flu outbreaks globally.

Another tool, HealthMap, which is sponsored by Boston Children's Hospital, mines online news reports to track outbreaks in real time. Sickweather draws from posts on Twitter and Facebook that mention the flu for its data.

People can be flu-hunters themselves with Flu Near You, a project that asks people to report their symptoms once a week. So far more than 38,000 people have signed up for this crowdsourced virus tracker. And of course, there's an app for that.

Both Finelli, a Flu Near You user, and Polgreen find the new tools exciting but agree that they have limits. "It's not as if we can replace traditional surveillance. It's really just a supplement, but it's timely," said Polgreen.

When people have timely warning that there's flu in the community, they can get vaccinated, and hospitals can plan ahead. According to a 2012 study in Clinical Infectious Diseases, Google Flu Trends has shown promise predicting emergency room flu traffic. Some researchers are even using a combination of the web database and weather data to predict when outbreaks will peak.

As for the current flu season, it's still impossible to predict week-to-week peaks and troughs. "We expect that it will last a few more weeks, but we can never tell how bad it's going to get," said Finelli.

Hospitals are already taking precautionary measures. One Pennsylvania hospital erected a separate emergency room tent for additional flu patients. This week, several Illinois hospitals went on "bypass," alerting local first responders that they're at capacity—due to an uptick in both flu and non-flu cases—so that patients will be taken to alternative facilities, if possible.

In the meantime, the CDC advises vaccination, first and foremost. On the bright side, the flu vaccine being used this year is a good match for the H3N2 strain. Though Finelli cautions, "Sometimes drifted strains pop up toward the end of the season."

It looks like there won't be shortages of seasonal flu vaccine like there have been in past years. HealthMap sports a Flu Vaccine Finder to make it a snap to find a dose nearby. And if the flu-shot line at the neighborhood pharmacy seems overwhelming, more health departments and clinics are offering drive-through options.

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Judge: Holmes Can Face Trial for Aurora Shooting

Jan 10, 2013 8:45pm

(Arapahoe County Sheriff/AP Photo)

In a ruling that comes as little surprise, the judge overseeing the Aurora, Colo., theater massacre has ordered that there is enough evidence against James Holmes to proceed to a trial.

In an order posted late Thursday, Judge William Sylvester wrote that “the People have carried their burden of proof and have established that there is probable cause to believe that Defendant committed the crimes charged.”

The ruling came after a three-day preliminary hearing this week that revealed new details about how Holmes allegedly planned for and carried out the movie theater shooting, including how investigators say he amassed an arsenal of guns and ammunition, how he booby-trapped his apartment to explode, and his bizarre behavior after his arrest.

PHOTOS: Colorado ‘Dark Knight Rises’ Theater Shooting

Holmes is charged with 166 counts, including murder, attempted murder and other charges related to the July 20 shooting that left 12 people dead and 58 wounded by gunfire. An additional 12 people suffered non-gunshot injuries.

One of the next legal steps is an arraignment, at which Holmes will enter a plea. The arraignment was originally expected to take place Friday morning.

Judge Sylvester indicated through a court spokesman that he would allow television and still cameras into the courtroom, providing the outside world the first images of Holmes since a July 23 hearing. Plans for cameras in court, however, were put on hold Thursday afternoon.

“The defense has notified the district attorney that it is not prepared to proceed to arraignment in this case by Friday,” wrote public defenders Daniel King, Tamara Brady and Kristen Nelson Thursday afternoon in a document objecting to cameras in court.

A hearing in the case will still take place Friday morning. In his order, Judge Sylvester said it should technically be considered an arraignment, but noted the defense has requested a continuance.  Legal experts expect the judge will grant the continuance, delaying the arraignment and keeping cameras out of court for now.

Sylvester also ordered that Holmes be held without bail.

Holmes’ attorneys have said in court that the former University of Colorado neuroscience student is mentally ill. The district attorney overseeing the case has not yet announced whether Holmes, now 25, can face the death penalty.

SHOWS: World News

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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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Israeli, US defence chiefs discuss Middle East issues

WASHINGTON: US Defence Secretary Leon Panetta and his Israeli counterpart Ehud Barak met to underscore a "strong US commitment to Israel's security", the Pentagon said.

US Defence Department spokesman George Little said in a statement that the two men "discussed a range of issues, and expressed their commitment to ensuring continued cooperation on many important regional issues -- particularly Syria, Iran, and Gaza".

"The secretary commended Minister Barak on his tireless efforts in advancing the US-Israel strategic relationship," Little said, adding the pair "reiterated the strong US commitment to Israel's security and the strong US-Israel defence relationship."

The meeting was the 11th for Barak and Panetta, who is leaving his post shortly.

President Barack Obama has nominated former US senator Chuck Hagel to succeed Panetta, a longtime Washington figure who has said he will be leaving public life.

- AFP/al

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Kin bid tearful adieu to soldier killed by Pakistan troops

MATHURA: Hundreds of villagers joined family in bidding adieu on late Wednesday evening to deceased Lance Naik Hemraj Singh, who was killed by Pakistan troops during a ceasefire violation in Jammu and Kashmir.

In Singh's native village of Shernagar under Mathura district of Uttar Pradesh, scores of locals flocked to the soldier's residence to honour him.

The inconsolable family of the soldier comprising an ageing mother, his wife, two daughters and a toddler son was seen being pacified by local women.

Army officials who escorted Singh's coffin from New Delhi participated in the last rite and also gave a rifle salute by firing several rounds in the air in honour of the soldier who died at the hands of the enemy at the Line of Control (LoC).

Lance Naik Hemraj, one of the two Indian soldiers killed by Pakistani troops in a violation of truce on the Kashmir border, was the family's sole breadwinner.

Hemraj, who joined the Army in 2001, was the second of three brothers and the sole earning member of his family after the death of his father.

Pakistani troops crossed the territory's heavily militarised LoC on Tuesday (January 08) and fired at an Indian army patrol.

The body of one of the soldiers was found "badly mutilated" in a forested area on the side controlled by India, Indian military officials said. Pakistan has denied the allegation.

The army had said that in a separate incident later on Tuesday, both sides shot at each other for more than an hour across the Line of Control (LoC) that divides Jammu and Kashmir.

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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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