Sharks use Earth’s magnetic fields as a map when making long-distance migrations, scientists say


Sharks are the ocean’s world travellers, swimming thousands of kilometres a year to their favoured locations.

But how do they pull off these impressive feats of navigation without looking out for landmarks?

A US team has shown that sharks use the Earth’s magnetic fields as a map when making long-distance migrations to specific locations.

The findings are published today in the journal Current Biology.

“Even when they’re far away, the animals know where they are and where to swim to get home,” said study co-author Bryan Keller at Florida State University. 

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Magnetic map readers?

Many species of sharks, skates and rays travel far and wide in the ocean, with some species returning to the same locations each year.

In 2005, a great white shark called “Nicole” made a record-breaking return trip from South Africa to Australia, swimming over 20,000 kilometres in just nine months.

For half a century, researchers have suspected that sharks are sensitive to magnetic fields, which could be used for navigation.

Other animals like sea turtles, lobsters and newts are known to be magnetically sensitive, but no-one has been able to confirm whether sharks are too.

Homeward bound

To find out, Mr Keller and colleagues captured 20 juvenile bonnethead sharks – a small coastal species that return to the same estuaries each year – from off the coast of Florida.

They brought the sharks back to the lab and placed them in holding tanks.

Surrounding the tanks were wooden frames with copper wires running along their edges.

The team built frames with copper wires to recreate the magnetic fields in locations where sharks frequent. (

Supplied: Keller et al./Current Biology

)

By tweaking the current running through these wires, the researchers were able to recreate the magnetic fields the sharks would experience in three different locations.

When the team adjusted the current to match conditions 600 kilometres south of where the sharks were collected from, they swam in a northward direction, indicating that they were able to read the magnetic field like a map to guide them home.

They also checked what happened when the magnetic field values north of Florida, in the middle of the state of Tennessee, were reproduced.

In this case, the sharks showed no particular swimming preference.

The researchers reasoned this might be because the sharks’ magnetic map-reading abilities were learned from locations they frequent.

Since they would never have experienced a land-based magnetic field before, the animals would not be able to rely on it to navigate.

A shark in a tank
The researchers exposed the sharks to different magnetic fields and tracked their swimming direction.(

Supplied: Bryan Keller

)

And when the researchers exposed the sharks to the magnetic field conditions of the site where they were captured from, they didn’t swim in a particular direction as they were already “home”.

“This suggests that sharks have an amazing ability to detect and navigate using the Earth’s magnetic field,” said Nathan Hart, a neurobiologist at Macquarie University who was not involved in the study.

All in the genes

The researchers also wanted to explore whether magnetic fields could help explain another mystery: why sharks from the same species are genetically distinct in different locations?

The team compared mitochondrial genes (passed down from the mother) and nuclear genes (inherited from both parents) in bonnethead sharks from various locations in the northwest Atlantic Ocean.

They also tracked the difference in magnetic field values, sea surface temperatures, and coastal distances between the locations.

It turned out that the magnetic fields across the locations accounted for more variation in the sharks’ mitochondrial DNA than temperature and distance. 

This suggests that on an evolutionary scale, females that initially colonised an area may have selected it based on similarities between the magnetic fields of that location and the one they originally came from, Mr Keller said.

This tendency to stick to specific locations means that sharks don’t cross paths with far-flung members of the same species, leading to genetically distinct groups scattered throughout the Atlantic Ocean.

A built-in compass?

While it’s clear that sharks rely on magnetic navigation to cruise the seas, the next step is figuring out how they pick up on these magnetic cues.

Even though there are no shortage of theories on how animals, including sharks, can detect magnetic fields — from the presence of light-sensitive pigments in the eye to tiny crystals of magnetite in the nose and head — scientists are still scratching their heads. 

For instance, migratory birds also use the Earth’s magnetic fields to guide their flights paths, but they are only able to pick up on them during the day, suggesting that light plays a role.

However, other animals, such as turtles, are able to read magnetic maps in complete darkness.

“This is definitely still an unsolved mystery in biology,” Professor Hart said.

“Given how many animals detect and orient to the Earth’s magnetic field, it’s an important one to solve.”

Mr Keller said that it would be also interesting to explore whether magnetic fields generated by human activities — such as underwater cables and offshore wind farms — throw off sharks’ sense of direction. 

“If a shark is using magnetic navigation to find a target and it detects an anomaly, it could get confused.”

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Gold Fields extends Perenti contract



Perenti’s underground mining division has secured a $200 million extension of works on Gold Fields’ Agnew operations in WA.

Thank you for dropping in to My Local Pages and seeing this story involving West Australian news called “Gold Fields extends Perenti contract”. This news release was presented by MyLocalPages as part of our local and national news services.

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Melbourne City to call Casey Fields home


The “Team 11” bid for A-League inclusion is over after glamour club Melbourne City’s decision to tap into a potential supporter base of 1.9 million people with their move to a new sports facility in southeast Melbourne.

The club’s new Etihad City Football Academy will be located at Casey Fields, already the home of the Melbourne Demons’ AFL, AFLW and VFL teams.

The academy will include an elite training tablet pitch, four full-sized floodlit pitches, a two-storey elite performance and headquarters building and eventually a 4000-capacity mini stadium.

Currently based at La Trobe University in Bundoora, City’s move comes after signing a heads of agreement with the City of Casey and City of Greater Dandenong.

It’s a move that has met the approval of the region’s “Team 11”, who had promised to keep fighting for A-League inclusion despite being beaten by Western United to a licence in 2018.

“Team 11 was different to all the other bids,” said Team 11 project manager Matt Windley, who initiated talks with Melbourne City 18 months ago.

“It was community driven, it was grassroots driven, it was driven by the councils.

“We didn’t care what the team was. We just wanted a team out here because it’s the most multicultural place in Australia, it’s got grassroots soccer clubs coming out its noses … we’re a long way from the city.

“We wanted a team to call our own … we don’t get to choose the name, we don’t get to choose the colours but in terms of what it does for community, everybody wins with Melbourne City.

“Team 11 dies but it’s because of Team 11 that this is happening. Melbourne City is our team.”

Melbourne City CEO Brad Rowse said: “Our infrastructure strategy is fundamental to the success of Melbourne City and City Football Group, creating the foundation for our long-term and sustainable growth.

“The opportunity presented at Casey Fields is clear – a brand-new purpose-built facility with bigger capacity, more pitches and right in the heart of a diverse and growing community with a deep footballing tradition.

“Today’s announcement marks the end of an extensive process and the beginning of an exciting journey.

“We are delighted to call southeast Melbourne our new home.”

City of Greater Dandenong Mayor Angela Long said: “Today’s announcement is an incredible reward for four years of hard work by many people across the City of Greater Dandenong, the City of Casey and Cardinia Shire,”

“Our previous southeast Melbourne A-League bid set out to foster grassroots football development with professional pathways, to connect with and grow our burgeoning business community, to market the region to national and international audiences and to provide a platform for community outreach programs.

“The proposed Dandenong Sports and Events Centre was an important part of that bid, and today’s announcement marks a step forward in bringing that idea to life.

“In Melbourne City FC we have found an established and well-loved partner with the same long-term and sustainable approach to development, a deep-rooted passion for community and a global network through its owners City Football Group.”

City’s move is sure to increase their small fan base, with football the number one participation sport in southeast Melbourne.

There are 115 grassroots clubs and 23,000 registered players across the wider region, which has a population of 1.9 million people.

City’s academy will shift to the already completed “stage 1” community and academy facilities in February 2021.

“Stage 2” facilities will be completed by early 2022 when City takes full occupation of the site.

City’s W-League team will play their first home match of the season on January 2 at Dandenong City Soccer Club.

“To be able to welcome Melbourne City’s extraordinary W-League team within a matter of weeks makes today’s announcement all the more exciting and will serve as a huge inspiration to young girls across Greater Dandenong and the region,” Ms Long said.



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‘New Acts will turn farmers labourers in their own fields’


The Bharath bandh called by different organisations was a grand success on Tuesday. The bandh was complete with shutters downed at many mandal headquarters and Telangana Rashtra Samithi (TRS) activists taking an active role.

The bandh was observed in support of the farmers agitating in New Delhi demanding repeal of three farm Acts passed in Parliament.

At several places, tractors with party flags flying high were parked on the highway at Toopran whike police remained mute spectators.

At Sangareddy, traffic came to a standstill. All the three highways — Nanded -Akola, Mumbai Highway and Nagapur Highway — were blocked for more than five hours. Slogans were raised against the Union government

People struck in vehicles suffered for want of water and food.

Addressing a gathering here, Finance Minister T. Harish Rao, who led the agitation, said the entire nation was supporting the agitation by farmers. He said that in 1967, minimum support price of ₹65 per quintal for wheat was introduced by the then agriculture minister Jagjivan Ram and presently 23 crops were covered by it.

“The new farm Acts will benefit corporate organisations and harm the interests of farmers. More than 92.5 % farmers across the State are having less than five acrest. The Cotton Corporation of India (CCI) has issued orders that only 40 quintals per farmer will be procured for acre. The Centre has warned that 60 lakh metric tonnes of paddy will not be procured from the State if bonus is given to fine variety paddy. Let us create awareness among farmers on these Acts. Even while Prime Minister of Britain has responded on the agitation of Indian farmers, our Prime Minister is silent,” said Mr. Harish Rao.

Referring to the farm Acts, he questioned whether small farmers would be in a position to sell the produce at far-off place as majority were small farmers. Farmers would become labourers in their own field with corporate farming. On removing the limit of godown stock, the Minister said this would also benefit corporate entities as farmers could not stock produce for long.

“For the past one month, farmers from Punjab and Haryana have been on the road. We have to save farmers. Now, roads were dug to prevent farmers entering New Delhi,” said Lok Sabha member K. Prabhakar Reddy.

MLC Farooq Hussain, and Forest Development Corporation chairman Onteru Pratap Reddy were present.



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Trump’s court nominee fields tough questioning on second day of hearings


Donald Trump”s Supreme Court nominee Amy Coney Barrett faced a second day of questions on Capitol Hill on Tuesday where Democratic senators grilled her on issues such as abortion, healthcare, and a potential election fight.

The nominee, a favourite for conservatives, insisted that she did not have a personal agenda, stating that she would decide cases “as they come.”

Barrett, a 48-year-old appellate court judge, was nominated to replace liberal icon Justice Ruth Bader Ginsburg who died last month due to complications from pancreatic cancer.

Her nomination to the court would create a 6-3 conservative majority, tilting the court to the right for years to come.

On her second day of hearings, she insisted her personal conservative views would not influence her legal judgements.

“Judges can’t just wake up one day and say I have an agenda, I like guns, I hate guns, I like abortion, I hate abortion, and walk in like a royal queen and impose their will on the world,” Barrett told the Senate Judiciary Committee during its second day of hearings.

“It’s not the law of Amy,” she said. “It’s the law of the American people.”

The top Democrat on the panel Senator Dianne Feinstein said it was “distressing not to get a good answer” on how Barrett would handle landmark abortion cases including Roe v Wade and the follow up case Planned Parenthood v Casey.

“I don’t have an agenda to try to overrule Casey,” Barrett said. “I have an agenda to stick to the rule of law and decide cases as they come.”

But she also declined to characterise Roe v Wade as a “super-precedent” case that should not be overturned.

“Let’s not make any mistake about it,” said Senator Kamala Harris, the Democratic vice presidential candidate, who said that allowing Trump to fill the seat with Barrett “poses a threat to safe and legal abortion in our country.”

Barrett, like her former mentor Justice Antonin Scalia, says she is an originalist, meaning she interprets the Constitution’s text as it was written at the time.

“I interpret the Constitution as a law, that I interpret its text as text and I understand it to have the meaning that it had at the time people ratified it. So that meaning doesn’t change over time. And it’s not up to me to update it or infuse my own policy views into it,” Barrett said.

Republicans have defended Barrett’s personal views and Catholic faith against criticism on her potential views on abortion and same-sex marriage.

Senate Republicans have rushed through the nomination hoping to confirm the judge before the November 3 election. The same Senators refused to confirm Barack Obama’s 2016 candidate because it was eight months before an election.

But if confirmed, Barrett would join the court before a challenge to the Affordable Care Act, otherwise known as Obamacare, that Republicans have tried to repeal.

Barrett told Senators she is “not hostile” to the law despite past writings that have been perceived as critical of it.

“I’m not here on a mission to destroy the Affordable Care Act,” Barrett said. Yet she struggled to answer specifics about the law as well.

On racism in the US, she said it “persists” and that the death of George Floyd at the hands of police had a “very personal” effect on her family.

But she told Democratic Senator Dick Durbin that “making broader diagnoses about the problem of racism is kind of beyond what I’m capable of doing as a judge.”

She also declined to say whether she would recuse herself from any election related cases.

Senator Lindsay Graham has set an initial committee vote on Barrett’s nomination for Thursday, underscoring Republicans’ confidence and goal to allow the full Senate to vote on her nomination by the end of the month.



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SuperCoach Racing: It’s time to strike while scoring opportunities are high, with short fields in big Group 1 races, SuperCoach, Racing, horse racing, Ranvet Stakes, George Ryder Stakes, Rosehill Guineas, William Reid Stakes, Rosehill, The Valley


As SuperCoach Racing moves into Round 3 this weekend, here’s everything you need to know about the dual-track race round which begins tonight at The Valley and continues tomorrow at Rosehill, with two massive opportunities to maximise scoring with limited starters in two Group 1 races.

Watch more than 50 sports LIVE & On-Demand on KAYO. New to Kayo? Get your 14-day free trial & start streaming instantly >

It’s been a crazy few weeks to kick off the SuperCoach Racing season, with packed schedules, and now the threat of COVID-19 disrupting the plans of trainers and jockeys in Victoria where restrictions are being put in place.

Victorian jockeys will be split into two groups – the best Category 1 hoops in Melbourne will be isolated and banned from riding at trackwork and jumpouts, saving themselves for race days only, with this isolation method set to apply AFTER Saturday’s racing.



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Karnataka plans industrial park at Kolar Gold Fields, requests Centre to hand over part of gold mines land


Bengaluru: Karnataka is pursuing plans to set up an industrial park on 3,200 acres of unused land owned by Bharat Gold Mines (BGML) at Kolar Gold Fields, about 94 kilometres from Bengaluru. Chief minister BS Yediyurappa and industries minister Jagadish Shettar discussed the subject with Union Minister for Coal, Mines and Parliamentary Affairs Pralhad Joshi on Friday.

The central public sector undertaking owns 12,109 acres at KGF, part of which could be used for setting up an industrial park.

The location is ideal for solar manufacturers, automobile units, electronics and pharmaceutical companies to invest as it is well connected by expressway and railway, the chief minister said while chairing a high level meeting that reviewed mining and geology related issues. The availability of land, Shettar said, will be known in six months after the mines and geology department conducts a survey to see if the place has any mineral deposits. If it is free of any major natural resources, then the Karnataka Industrial Areas Development Board (KIADB) will take approvals from the Centre, and begin work on setting up the park.

KGF is about 90 km from Bengaluru International Airport, 260 km from Chennai port and 314 km from Krishnapatnam port, and hence, is strategically located, the minister said. The site has the required infrastructure to set up a full-fledged industrial park and generate jobs in Kolar district.

The initiative is part of the state government’s efforts to attract investments in places away from Bengaluru and take industrial development across the state.





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Extreme weather conditions force road closures in NSW, good falls in snow fields


A strong cold front has brought widespread snow falls and ice, closing roads in the New South Wales’ Central West and Southern Highlands.

But skiers are celebrating, with good falls at Perisher and Thredbo.

Sixty-six centimetres of snow fell overnight at Perisher and the resort is expecting further blizzard conditions today.

Drivers are warned to watch out for icy roads in the region.

The Great Western Highway between Bathurst and Marrangaroo and the Mitchell Highway from Shadforth to Dunkeld, west of Bathurst are both closed.

Jenolan Caves Road is also closed between Hampton and Hartley due to the extreme conditions.

Snow has fallen at Millthorpe in the NSW Central West.(ABC News: Mollie Gorman)

a fish statue underneath heavy snow
The Big Trout Motor Inn in Oberon in central western NSW this morning.(Instagram: mcarpo)

People in the Central West of the state are out sightseeing and locals said the snow was falling, “a lot heavier and thicker than usual”.

Don Stafford from Yetholme Crest, west of Lithgow, said he had received “about three inches”.

“It’s very cold, it’s not very interesting … you don’t want to spend much time out there,” he said.

“I’m staying inside from now on, I’ll watch a few replays of the football.”

People in snow.
People enjoying the conditions at Blackheath in the Blue Mountains.(ABC News: Lydia Feng)
A road with snow.
A road near Millthorpe.(ABC News: Mollie Gorman)

Alicia Hewitt, from the Millthorpe Corner Store, said the snow had brought a lot of people in.

“Mainly visitors I think, a lot of locals have chosen to stay in bed in the warmth, but visitors come out to see the snow.”

The State Emergency Service (SES) says damaging winds will also affect much of the state today, with a gale warning issued for the Illawarra, Macquarie Coast, Hunter Coast, and Eden Coast.

Damaging winds are expected to continue over the weekend, SES spokeswoman Sharon Ladeira said.

“People need to obviously move their cars away from trees secure or put loose items away from your house or balcony. Those damaging winds are expected to continue until at least the first part of Sunday,” she said.

There is also a strong wind warning for Sydney as well as the Byron, Batemans and Coffs Coasts.

Heavy snow on top of cars.
Cars blanketed in snow at Oberon.(Facebook: Pat Henwood)



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Sunflower fields provide Instagram selfie profits for farms


Farmers and pick-your-own growers are capitalising on the power of social media by providing photo opportunities in sunflower fields.

One farm on Hayling Island, Hampshire, has reported an increase in business and up to 1,000 visitors a day.

They pay £5 per person to pick six sunflowers and take pictures.

Similar sites across England, including on the Isle of Wight, in the New Forest, Titchfield and Oxfordshire, have also reported record numbers.

Video by Emily Ford and Ben Moore



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Education polishes skills for many fields


We have children aged from three to over 18 years old, including some international students. The layers of complexity of caring for this age range, their unique learning styles, behaviours, dispositions and talents, and meeting the needs of our staff, current and future parents plus a network of past student alumni of over 10,000, means that the gaps between scheduled meetings are consumed every day in providing a personalised service to stakeholders.

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How long have you been doing this job and what first sparked your interest in this area?

This is my third year as a principal at Ivanhoe Girls’ and I was formerly the principal of the
Australian International School in Malaysia. Prior to that I was the head of Moreton Bay College
in Queensland.

My career goal was to be the best mathematics teacher I could be and to share and foster the love and passion of mathematics in my students.

I spent the first 18 months after university in a computer consultant role before my first full year as a teacher and, a year later, an appointment as a head of computer studies in an independent girls’ school. I then became a senior computing lecturer at TAFE.

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I left work to become a stay-at-home mum for seven-and-a-half years, then returned to teaching.

I had roles as a year level co-ordinator, academic counsellor and head of mathematics before being offered a role as head of practicum at Bond University and, later, head of education.

The increasing pull to have greater direct engagement with students and their education led me to return to the schooling sector as a head of senior school/deputy principal role in an independent girls’ school in Queensland.

What was the most unexpected thing you have had to do in your job?

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The most bizarre was the writing and implementation of a bodyguard policy for the Australian International School. In Malaysia, schools need to take a range of security measures that are unheard of in Australia. On any given day I had 12 guards who would be on duty at the school. In addition to the school security team, many children had their own private security arrangements.

What is the worst thing you have had to do?

Informing the year 10 cohort that they had lost one of their own and that we had lost precious members of our school community. It is at challenging times like these that you somehow find the strength to dig deeper into your personal reserves than you thought possible in order to ensure a community can move forward with optimism and hope.

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How transferable are your skills?

In particular, the negotiation skills you hone could be used in a political or diplomatic career, the leadership skills could be used to run a range of businesses and not-for-profit organisations and the human resource management skills could be used to provide leadership training across a broad range of industries.

The project-management skills required for facility management, plus the business and financial acumen required for strategic planning, are transferable to any role comparable to a CEO or business leader.

The emotional intelligence required to lead a community of learners, and facilitate an environment where everyone, from our youngest students to the teachers and professional staff, is in a situation where they can thrive as individuals, can sometimes require the skills of a life coach.

Did you have a different career before you became a teacher, and how were those skills relevant to what you do now?

I worked for 18 months as a computer consultant for a large computer company when I first graduated from Melbourne University. During the time in that role I was fortunate to be sent on many computer training courses in which I learnt about computers and their capability.

While I enjoyed many aspects of the job, I realised that I really did want to be a teacher and I had some new skills that would be of significant benefit to students. One year later, at 24 years of age, I had my first head-of-department role: head of computer studies at an independent girls’ school in Adelaide.

What advice do you have for people wanting to get into this career?

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There is no career, other than teaching, in which a person can have such a significant and profound positive influence on young people. The work is not easy and is often exhausting, but it is fulfilling, humbling and incredibly important.

There are many pathways to becoming a great teacher, and they do not always go through the traditional school-to-university-to-teaching path.

Some of the best teachers I have come across are those who have enjoyed rich life and career experiences before deciding to pivot to a career in teaching.

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