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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Oscar Nominations 2013: Full List













"Lincoln" is leading the way to the 2013 Oscars. This morning, the biopic about the 16th president picked up 12 Academy Award nominations, including best director for Steven Spielberg and best actor for Daniel Day-Lewis.


Ang Lee's "Life of Pi" followed close behind with 11 nominations. "Les Miserables" and "Silver Linings Playbook" tied for third place, with eight nominations each.


The Academy also named its eldest and youngest best actress nominees ever. "Beasts of the Southern Wild" star Quvenzhané Wallis, 9, is up for best actress along with "Amour" lead Emmanuelle Riva, 85.


See who made the cut below, and weigh in on who you want to win with Oscar.com's My Picks, an interactive and social Oscar ballot that allows you to pick who you think will win in each category. You can compete with your Facebook friends when the Academy Awards air on Feb. 24.


FULL COVERAGE: The 85th Annual Academy Awards


Best Picture:


"Beasts of the Southern Wild"


"Silver Linings Playbook"


"Zero Dark Thirty"


"Lincoln"


"Les Miserables"


"Life of Pi"


"Amour"


"Django Unchained"


"Argo"


My Picks: Create an Oscar Ballot and Play With Friends


Best Supporting Actor:


Christoph Waltz, "Django Unchained"


Philip Seymour Hoffman, "The Master"


Robert De Niro, "Silver Linings Playbook"


Alan Arkin, "Argo"


Tommy Lee Jones, "Lincoln"


PHOTOS: 2013 Oscar Nominees


Best Supporting Actress:


Sally Field, "Lincoln"


Anne Hathaway, "Les Miserables"






David James/Dreamworks/AP











Seth MacFarlane, Emma Stone Discuss Oscar Nominations Watch Video









Jacki Weaver, "Silver Linings Playbook"


Helen Hunt, "The Sessions"


Amy Adams, "The Master"


RELATED: Oscar's Likely Winners


Best Director:


David O. Russell, "Silver Linings Playbook"


Ang Lee, "Life of Pi"


Steven Spielberg, "Lincoln"


Michael Haneke, "Amour"


Benh Zeitlin, "Beasts of the Southern Wild"


Best Actor:


Daniel Day Lewis, "Lincoln"


Denzel Washington, "Flight"


Hugh Jackman, "Les Miserables"


Bradley Cooper, "Silver Linings Playbook"


Joaquin Phoenix, "The Master"


Best Actress:


Naomi Watts, "The Impossible"


Jessica Chastain, "Zero Dark Thirty"


Jennifer Lawrence, "Silver Linings Playbook"


Emmanuelle Riva, "Amour"


Quvenzhané Wallis, "Beasts of the Southern Wild"


Best Original Screenplay:


"Zero Dark Thirty"


"Django Unchained"


"Moonrise Kingdom"


"Amour"


"Flight"


Best Adapted Screenplay:


"Lincoln"


"Silver Linings Playbook"


"Argo"


"Life of Pi"


"Beasts of the Southern Wild"


Best Animated Feature:


"Frankenweenie"


"The Pirates! Band of Misfits"


"Wreck-It Ralph"


"Paranorman"


"Brave"


Best Foreign Feature:


"Amour"


"A Royal Affair"


"Kon-Tiki"


"No"


"War Witch"


Best Visual Effects:


"Life of Pi"


"The Hobbit: An Unexpected Journey"


"The Avengers"


"Prometheus"


"Snow White and the Huntsman"


Best Cinematography:


"Skyfall"


"Anna Karenina"


"Django Unchained"


"Life of Pi"


"Lincoln"


Best Costume Design:


"Anna Karenina"


"Les Miserables"


"Lincoln"


"Mirror Mirror"


"Snow White and the Huntsman"


Best Documentary Feature:


"Searching for Sugar Man"


"How to Survive a Plague"


"The Gatekeepers"


"5 Broken Cameras"


"The Invisible War"


Best Documentary Short:


"Open Heart"


"Inocente"


"Redemption"


"Kings Point"


"Mondays at Racine"


"Snow White and the Huntsman"


Best Film Editing:


"Lincoln"


"Silver Linings Playbook"


"Life of Pi"


"Argo"


"Zero Dark Thirty"


Best Makeup and Hairstyling:


"Hitchcock"


"The Hobbit: An Unexpected Journey"


"Les Miserables"


Best Music (Original Score):


"Anna Karenina"


"Argo"


"Life of Pi"


"Lincoln"


"Skyfall"


Best Music (Original Song):





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Many bills name post offices; another snag for Hagel; and the inauguration soundtrack (read-this roundup)





(Justin Sullivan - Getty Images)
Here’s what the Loop is reading today:



Congress goes postal — Who says Congress can’t tackle the tough issues? A new analysis finds that an astonishing “15 percent of all bills passed and signed into law in the last five congresses named a post office.”



Nomination snag — So much for moving quickly on nominations. Sen. Lindsay Graham (R-S.C.) wants to wait to take action on the nomination of John Brennan to be CIA director until the Obama administration gives Congress the answers he’s been seeking on the terrorist attacks in Libya.



Inauguration soundtrack — Obama bestie Beyonce is among the big names performing at the inaugural concert. And poet Richard Blanco (who unlike Blue Ivy’s mom, you won’t read about in every issue of US Weekly) will read at the swearing-in ceremony.

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Hong Kong leader survives impeachment bid






HONG KONG: Hong Kong pro-democracy lawmakers failed in an unprecedented bid on Wednesday to impeach the city's embattled Beijing-backed leader, after they accused him of breaking housing laws and urged him to quit.

The city's first impeachment motion, which accused Leung Chun-ying of lying, dereliction of duty and serious breaches of the law in a row stemming from illegal structures at his luxury home, was denied after eight hours of debate.

The 27 pro-democracy lawmakers who signed the joint motion -- which they said was a symbolic move -- voted in favour, while 37 voted against in the 70-seat legislature which is dominated by pro-Beijing members.

Wednesday's vote followed a protest on New Year's Day in which tens of thousands took to the streets to urge Leung to quit and to press for greater democracy, 15 years after the city returned to Chinese rule.

The former British colony maintains a semi-autonomous status, with its own legal and judicial system, but cannot choose its leader through the popular vote.

Leung took office in July after he was picked by a 1,200-strong election committee dominated by pro-Beijing elites, amid rising anger over what many perceive to be China's meddling in local affairs.

China has said the chief executive could be directly elected in 2017 at the earliest, with the legislature following by 2020.

Unauthorised structures are a politically sensitive issue in the space-starved city of seven million and demonstrators have used the scandal to press for universal suffrage in choosing Hong Kong's leader.

Leung secured the chief executive role after criticising his rival Henry Tang over illegal structures at Tang's home.

But he has since acknowledged and apologised for structures at his own home which were built without planning permission.

Maverick lawmaker "Long Hair" Leung Kwok-hung, wearing a T-shirt reading "We topple a tyrant", accused the new leader of lying about his own structures during campaigning when he presented the impeachment motion earlier on Wednesday.

"He has used dishonest ways to win the election," he said.

Chief Secretary Carrie Lam, second in command in Leung's administration, said the motion was unnecessary and urged lawmakers to work together on policy and livelihood issues.

But Democratic Party chairwoman Emily Lau said the motion was a symbolic gesture to show the deepening public mistrust toward Leung, claiming the leader had "cheated his way to power".

"This is the first time we have a motion in the legislature to impeach a cheating chief executive," she said.

If the motion had been passed, the city's highest court would have had to initiate an investigation. At least two-thirds of the legislature would need to endorse a guilty finding before Leung could be removed from office.

Earlier, rival protesters traded barbs outside the legislature and security personnel had to step in at one point when an angry pro-government supporter charged towards the rival group, TV footage showed.

Leung's popularity ratings have fallen since the controversy, with discontent over issues including sky-high property prices and anti-Beijing sentiment remaining high.

- AFP/xq



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Severed head of Indian soldier yet to be found: Army

RAJOURI/NEW DELHI: The Indian Army on Wednesday said both the soldiers killed during an attack by Pakistani troops across the Line of Control (LoC) in Jammu and Kashmir were decapitated and that one severed head was yet to be recovered.

"The bodies of two soldiers were brutalised — one head was severed and another body was beheaded... It (the head of one of jawan) has not being recovered — probably they have taken it along with them", deputy commander of the 25 Division Brigadier J K Tiwari told reporters in Rajouri.

The Army had not been able to recover the head of Lance Naik Sudhakar Singh, he said. Singh was killed along with Lance Naik Hemraj in Tuesday's unprovoked attack in Medhar area in Poonch sector.

The Army on Tuesday said one of the two bodies was mutilated while other sources said the heads of both the Indian soldiers have been chopped off and that one was taken away by Pakistani intruders.

According to Army sources in Delhi, the Pakistan army regulars who were involved in the attack wore black uniforms and they had slit the throats of both the soldiers in a brutal manner and that the bodies were badly mutilated.

Giving details about the incident, Tiwari said eight soldiers belonging to the 13 Rajputana Rifles were carrying out area domination patrolling (ADP) in two escort parties including 6 jawans on back side and two on the front about 600 metres inside the LoC.

Army officials said the fence on the LoC in that particular area in Krishna Ghati is built 2 Kms inside Indian territory and the Pakistani troops did not have to cross the obstacle to enter Indian territory.

Then men wearing black clothes, suspected to be from the Pakistani special forces, took benefit of the thick fog and dense forests and laid ambush, Tiwari said, adding that they fired on patrol party and fire fight continued for 30 minutes. There were also reports that the Pakistani troops belonged to 29 Baloch regiment.

"After the firing stopped, patrol parties moved ahead and came acoss the two dead jawans in a mutilated condition", he said. The incident took place near the Sona Gali area close to the LoC.

The Mendhar area has been the hub of ceasefire violations and cross-border firings in the last one year with close to 90 such incidents.

The area is known as the Barasingha battalion area and is under the overall command of the 10 brigade of the Indian Army.

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Pictures: Wildfires Scorch Australia Amid Record Heat

Photograph by Jo Giuliani, European Pressphoto Agency

Smoke from a wildfire mushrooms over a beach in Forcett, Tasmania, on January 4. (See more wildfire pictures.)

Wildfires have engulfed southeastern Australia, including the island state of Tasmania, in recent days, fueled by dry conditions and temperatures as high as 113ºF (45ºC), the Associated Press reported. (Read "Australia's Dry Run" inNational Geographic magazine.)

No deaths have been reported, though a hundred people are unaccounted for in the town of Dunalley, where the blazes destroyed 90 homes.

"You don't get conditions worse than this," New South Wales Rural Fire Service Commissioner Shane Fitzsimmons told the AP.

"We are at the catastrophic level, and clearly in those areas leaving early is your safest option."

Published January 8, 2013

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Hospitals Flooded With Flu Patients













U.S. emergency rooms have been overwhelmed with flu patients, turning away some of them and others with non-life-threatening conditions for lack of space.


Forty-one states are battling widespread influenza outbreaks, including Illinois, where six people -- all older than 50 -- have died, according to the state's Department of Public Health.


At least 18 children in the country have died during this flu season, according to the U.S. Centers for Disease Control and Prevention.


The proportion of people seeing their doctor for flu-like symptoms jumped to 5.6 percent from 2.8 percent in the past month, according to the CDC.


Northwestern Memorial Hospital in Chicago reported a 20 percent increase in flu patients every day. Northwestern Memorial was one of eight hospitals on bypass Monday and Tuesday, meaning it asked ambulances to take patients elsewhere if they could do so safely.


Dr. Besser's Tips to Protect Yourself From the Flu








Earliest Flu Season in a Decade: 80 Percent of Country Reports Severe Symptoms Watch Video











Flu Season Hits Country Hard, 18 States Reach Epidemic Levels Watch Video





Most of the hospitals have resumed normal operations, but could return to the bypass status if the influx of patients becomes too great.


"Northwestern Memorial Hospital is an extraordinarily busy hospital, and oftentimes during our busier months, in the summer, we will sometimes have to go on bypass," Northwestern Memorial's Dr. David Zich said. "We don't like it, the community doesn't like it, but sometimes it is necessary."


A tent outside Lehigh Valley Hospital in Salisbury Township, Pa., was set up to tend to the overflowing number of flu cases.


A hospital in Ohio is requiring patients with the flu to wear masks to protect those who are not infected.


State health officials in Indiana have reported seven deaths. Five of the deaths occurred in people older than 65 and two younger than 18. The state will release another report later today.


Doctors are especially concerned about the elderly and children, where the flu can be deadly.


"Our office in the last two weeks has exploded with children," Dr. Gayle Smith, a pediatrician in Richmond, Va., said


It is the earliest flu season in a decade and, ABC News Chief Medical Editor Dr. Besser says, it's not too late to protect yourself from the outbreak.


"You have to think about an anti-viral, especially if you're elderly, a young child, a pregnant woman," Besser said.


"They're the people that are going to die from this. Tens of thousands of people die in a bad flu season. We're not taking it serious enough."



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India says two soldiers killed in clash with Pakistan troops






SRINAGAR, India: Pakistani troops killed two Indian soldiers on Tuesday near the tense disputed border between the nuclear-armed neighbours in Kashmir and one of the bodies was badly mutilated, the Indian army said.

The firefight broke out at about noon on Tuesday (0630 GMT) after an Indian patrol discovered Pakistani troops about half a kilometre (1,600 feet) inside Indian territory, an army spokesman told AFP.

A ceasefire has been in place along the Line of Control that divides the countries since 2003, but it is periodically violated by both sides and Pakistan said Indian troops killed a Pakistani soldier on Sunday.

Relations had been slowly improving over the last few years following a rupture in their slow-moving peace process after the 2008 attacks on Mumbai, which were blamed by India on Pakistan-based militants.

"There was a firefight with Pakistani troops," army spokesman Rajesh Kalia told AFP from the mountainous Himalayan region.

"We lost two soldiers and one of them has been badly mutilated," he added, declining to give more details on the injuries.

"The intruders were regular (Pakistani) soldiers and they were 400-500 metres (1,300-1,600 feet) inside our territory," he said of the clash in Mendhar sector, 173 kilometres (107 miles) west by road from the city of Jammu.

In Islamabad, a Pakistan military spokesman denied what he called an "Indian allegation of unprovoked firing". He declined to elaborate.

On Sunday, Pakistan said Indian troops had crossed the Line of Control and stormed a military post. It said one Pakistani soldier was killed and another injured.

It lodged a formal protest with India on Monday over what it called an unprovoked attack.

India denied crossing the line, saying it had retaliated with small arms fire after Pakistani mortars hit a village home.

A foreign ministry spokesman said Indian troops had undertaken "controlled retaliation" on Sunday after "unprovoked firing" which damaged a civilian home.

The deaths are set to undermine recent efforts to improve relations, such as opening up trade and offering more lenient visa regimes which have been a feature of talks between senior political leaders from both sides.

Muslim-majority Kashmir is a Himalayan region which India and Pakistan both claim in full but rule in part. It was the cause of two of three wars between the neighbours since independence from Britain in 1947.

- AFP/fa



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CPM, Trinamool workers clash in West Bengal

KOLKATA: A number of people were injured on Tuesday in firing and stone-pelting in clashes between the workers of ruling Trinamool Congress and the opposition CPM in West Bengal, leaders from rival parties claimed.

The clashes took place in South 24-Parganas district, about 30 km from here, in which over a dozen cars were reportedly torched.

When contacted, superintendent of police Pravin Tripathi conceded that there was a law and order issue, but could not provide any figures or details. "I don't have any data right now," Tripathi said.

CPM leaders alleged that 15 of their cadres were attacked with firearms at Bamanghata by Trinamool leader Arabul Islam and his men. The activists were among a large number of workers and leaders coming in a convoy of 60 vehicles to join a proposed demonstration at district headquarters Alipore against the attack on former minister Abdur Rezzak Mollah, party leaders said.

"Fifteen of our workers were injured. Three of them have bullet injuries. Two were hit by stones. Several are serious," said Communist Party of India-Marxist (CPM) Bhangar zonal committee secretary Sattar Mollah.

On the other hand, Arabul Islam alleged that his car came under fire from the convoy carrying CPM workers.

"I have chest and leg injury. When they started firing, I fell under the car. They continued to fire. Then my workers rescued me," said Arabul, who was taken to a hospital.

Trouble flared up at Bhangar since late last week as one party office each of the CPM and Trinamool were damaged and set afire respectively.

When CPM legislator Mollah went to the area, he was allegedly attacked by Trinamool workers, led by former Trinamool lawmaker Arabul.

Mollah has been admitted to a private hospital with multiple injuries, and the incident has triggered a political uproar.

Chief minister Mamata Banerjee, who was indisposed and earlier cancelled all her programmes, rushed to the state secretariat Writers' Buildings and held a high-level meeting with senior administrative and police officials to take stock of the situation.

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Primitive and Peculiar Mammal May Be Hiding Out in Australia



It’d be hard to think of a mammal that’s weirder than the long-beaked, egg-laying echidna. Or harder to find.


Scientists long thought the animal, which has a spine-covered body, a four-headed penis, and a single hole for reproducing, laying eggs, and excreting waste, lived only in New Guinea. The population of about 10,000 is critically endangered. Now there is tantalizing evidence that the echidna, thought to have gone extinct in Australia some 10,000 years ago, lived and reproduced there as recently as the early 1900s and may still be alive on Aussie soil.


The new echidna information comes from zoologist Kristofer Helgen, a National Geographic emerging explorer and curator of mammals at the Smithsonian Institution. Helgen has published a key finding in ZooKeys confirming that a skin and skull collected in 1901 by naturalist John T. Tunney in Australia is in fact the western long-beaked echidna, Zaglossus bruijnii. The specimen, found in the West Kimberley region of Western Australia, was misidentified for many years.


(More about echidnas: Get to know this living link between mammals and reptiles.)


Helgen has long been fascinated by echidnas. He has seen only three in the wild. “Long-beaked echidnas are hard to get your hands on, period,” he said. “They are shy and secretive by nature. You’re lucky if you can find one. And if you do, it will be by chance.” Indeed, chance played a role in his identification of the Australian specimen. In 2009, he visited the Natural History Museum of London, where he wanted to see all of the echidnas he could. He took a good look in the bottom drawer of the echidna cabinet, where the specimens with less identifying information are often stored. From among about a dozen specimens squeezed into the drawer, he grabbed the one at the very bottom.


(Related from National Geographic magazine: “Discovery in the Foja Mountains.”)


“As I pulled it out, I saw a tag that I had seen before,” Helgen said. “I was immediately excited about this label. As a zoologist working in museums you get used to certain tags: It’s a collector’s calling card. I instantly recognized John Tunney’s tag and his handwriting.”


John Tunney was a well-known naturalist in the early 20th century who went on collecting expeditions for museums. During an Australian expedition in 1901 for Lord L. Walter Rothschild’s private museum collection, he found the long-beaked echidna specimen. Though he reported the locality on his tag as “Mt Anderson (W Kimberley)” and marked it as “Rare,” Tunney left the species identification field blank. When he returned home, the specimen was sent to the museum in Perth for identification. It came back to Rothschild’s museum identified as a short-beaked echidna.


With the specimen’s long snout, large size, and three-clawed feet, Helgen knew that it must be a long-beaked echidna. The short-beaked echidna, still alive and thriving in Australia today, has five claws, a smaller beak, and is half the size of the long-beaked echidna, which can weigh up to 36 pounds (16 kilograms).



As Helgen began tracing the history and journey of the specimen over the last century, he crossed the path of another fascinating mind who had also encountered the specimen. Oldfield Thomas was arguably the most brilliant mammalogical taxonomist ever. He named approximately one out of every six mammals known today.


Thomas was working at the Natural History Museum in London when the Tunney echidna specimen arrived, still misidentified as a short-beaked echidna. Thomas realized the specimen was actually a long-beaked echidna and removed the skull and some of the leg bones from the skin to prove that it was an Australian record of a long-beaked echidna, something just as unexpected then as it is now.


No one knows why Thomas did not publish that information. And the echidna went back into the drawer until Helgen came along 80 years later.


As Helgen became convinced that Tunney’s long-beaked echidna specimen indeed came from Australia, he confided in fellow scientist Mark Eldridge of the Australian Museum about the possibility. Eldridge replied, “You’re not the first person who’s told me that there might be long-beaked echidnas in the Kimberley.” (That’s the Kimberley region of northern Australia.) Scientist James Kohen, a co-author on Helgen’s ZooKeys paper, had been conducting fieldwork in the area in 2001 and spoke to an Aboriginal woman who told him how “her grandmothers used to hunt” large echidnas.


This is “the first evidence of the survival into modern times of any long-beaked echidna in Australia,” said Tim Flannery, professor at Macquarie University in Sydney. “This is a truly significant finding that should spark a re-evaluation of echidna identifications from across northern Australia.”


Helgen has “a small optimism” about finding a long-beaked echidna in the wild in Australia and hopes to undertake an expedition and to interview Aboriginal communities, with their intimate knowledge of the Australian bush.


Though the chances may be small, Helgen says, finding one in the wild “would be the beautiful end to the story.”


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