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Dolphins are teaching each other how to use shells to catch and eat fish – CBC.ca

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The first time Sonja Wild saw a dolphin using an empty seashell to scoop an unwitting fish into its mouth, she got so excited she almost forgot to photograph it.

This rare and unique hunting technique is called “shelling” or “conching.” A hungry dolphin will chase a hard-to-catch fish into an empty seashell, then ferry the shell to the surface where the dolphin uses its beak to jostle the prey into its mouth. 

“Seeing it for the first time was just a ‘wow’ moment because you do not expect a shell popping up right next to the boat that is being carried by a dolphin. You kind of, like, drop everything,” said Wild, a behavioural ecologist at the University of Konstanz and the Max Planck Institute of Animal Behavior in Germany.

“I was definitely mind-blown,” she told As It Happens guest host Duncan McCue.

Wild is the lead author of a new study in the journal Current Biology that documents how conching has spread through dolphin populations as the clever creatures teach each other how to do it.

Scientists have observed instances of conching going back at least 10 years, though it has always been a rare sight. 

Wild says there was a major uptick in sightings in Shark Bay, off the coast of Western Australia, after a 2011 marine heat wave killed off a large number of sea snails, leaving their shells ripe for the picking.

Wild and her colleagues have been observing the Shark Bay dolphins for years, mapping their social and genetic relationships. Between 2007 and 2018, they identified 1,000 individual dolphins and saw 19 of them engage in conching 42 times.

While conching still appears to be quite rare, Wild says all the dolphins who do it know each other. 

Dolphins off the coast of Western Australia are teaching each other how to use empty shells to trap and eat fish, new research has found. (Sonja Wild/Dolphin Innovation Project)

While analyzing their population data, the researchers found that conching spreads horizontally within dolphin generations, meaning from peer to peer, as opposed to vertically, from mother to calf.

“That is indeed quite special because dolphins normally rely very much on their mothers for foraging behaviour,” Wild said.

“And we’re now showing for the first time that they are, indeed, capable of learning foraging behaviour outside of the mother-calf bond.”

Sonja Wild is a behaviorral ecologist at the University of Konstanz and the Max Planck Institute of Animal Behaviour. (Submitted by Sonja Wild/Photo-Spice)

Janet Mann, a dolphin researcher at Georgetown University who wasn’t involved in the study, told the New York Times it’s impossible to say definitively that peer imitation is the only way dolphins learn about conching, noting we’ve “barely scratched the water’s surface” when it comes to understanding the behaviour.

Wild agrees. 

“It is very much possible that some dolphins may have learned this by themselves, by just interacting with their shells and then by accident kind of lifting them above the surface,” she said.

She says it’s possible, too, that some dolphins are passing the skill down to their young. But her team’s models “clearly show that the majority have learned from their peers.”

Why do they do it?

Wild says she’s not sure why dolphins use shells to trap and eat fish.

She says they are very playful creatures, and it could be as simple as “just a little bit of fun to get your meal in a different way than usual.”

But whatever their motivation, it proves they can adapt to a changing environment and pick up new skills — an ability that could help them survive as climate change alters ocean populations and makes food more scarce, she said.

Wild has been studying the dolphins of Shark Bay, Australia, for years. (Sonja Wild/Dolphin Innovation Project)

“Learning from your mother is very useful in kind of stable environments that don’t change, because the parental behaviour is tested and stable and adapted to the environment. But as soon as the environment changes, the behaviour may become outdated or inefficient or even maladaptive,” Wild said.

“And in that case, it’s beneficial if you start looking around to see what other dolphins are doing.”

‘Humans are not the only ones with culture’

Picking up new tricks from friends is rare in the animal kingdom, Wild said. It’s a form of learning that’s usually only observed in primates, including apes, chimpanzees and, of course, humans.

“It certainly helps to understand their intelligence by knowing that they are capable of innovating such remarkable behaviour, but it also helps us to understand that dolphin societies are maybe not that different from us humans,” Wild said.

“They have very complex social relationships. They use tools. They are able to learn to use tools from one another. So it kind of helps our understanding that humans are not the only ones with culture.”


Written by Sheena Goodyear. Interview produced by Katie Geleff and Jeanne Armstrong.

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Researchers spotted something strange in space and can't explain it – lintelligencer

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Researchers spotted something strange in space and can’t explain it

Researchers have spotted a new class of radio objects in space that has never been documented before.

Known as ‘Odd Radio Circles’ or ORC, it’s believed they may be coming from a mysterious structure from another galaxy, unseen by human eyes.

The waves take the form of blasts of colourful circular objects, which were pinpointed by cameras during a survey by the Australian Square Kilometre Array Pathfinder telescope (ASKA).

Despite searching for an optical, infrared, or X-ray source to the pulses, none could be traced, leaving experts baffled.

Researchers have concluded it is a never before recorded phenomenon, a review in Nature Astronomy reports.

The results of the extraordinary study are still to be peer-reviewed but offer a tantalising glimpse of a deep space mystery that could one day yield answers about the mysteries of the universe.

Researchers zoomed in on the objects during a survey of the universe using the ASKA.

After three snaps of the mysterious ORCS were captured they were compared to the existing archive and found to match a similar radio wave structure located in March 2013.

The authors of the study note radio images are normally sphere space objects – like remnants of dying stars as well as proto-planetary discs

These new ORCs by contrast “appear to be a new class of astronomical objects” they said.

A team of Astrophysicists write: ” We have found an unexpected class of astronomical objects which have not previously been reported, in the Evolutionary Map of the Universe Pilot survey, using the Australian Square Kilometre Array Pathfinder telescope.

“The objects appear in radio images as circular edge-brightened discs about one arcmin diameter, and do not seem to correspond to any known type of object.

“We speculate that they may represent a spherical shock wave from an extra-galactic transient event, or the outflow, or a remnant, from a radio galaxy viewed end-on.

“Assumed to be not in any way connected with a supernova remnant—the structure left over after a massive star burst, it was deemed as a possible result of a spherical shock wave arising from galactic winds.

“While this is a theoretical possibility, such a shock has not yet been observed elsewhere.”

They added it is possible the strange discs represent a new category of a previously unknown phenomenon, “such as the jets of a radio galaxy”.

It is not the first time weird radio signals are speculated to be coming from another galaxy. In February Fast radio bursts were documented at the Canadian Hydrogen Intensity Mapping Experiment (CHIME) in British Columbia.

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Bright, rare comet lighting up Canadian skies for next few days – CityNews Vancouver

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WINNIPEG (CITYNEWS) – Stargazers across Canada and the world have been catching rare glimpses of the brightest comet of the last two decades – and there’s still time to do so.

Comet Neowise, named after the satellite that first discovered it, is headed toward Earth and will continue to light up the night sky for the next few days. The best times to see it are just after sunset and around 3 a.m.

Scott Young, manager of the Planetarium at the Manitoba Museum says the comet, which is composed of rock and ice, dates back to the origin of the solar system. 

“Most of the time, these are not something you can see without a telescope,” said Young. “But once in a while, one of these comets surprises us and gets brighter than expected, and that is what we are seeing here. It is visible to the unaided eye and from a location away from city lights.

“It’s really cool to see a comet like this. This is probably, almost certainly, the first time that any humans have seen this particular object.”

Young says the comet will get as close as 100 million kilometres from Earth, which is normally too far to be seen with the naked eye.

“For whatever reason, this comet has melted a lot and the tail has grown very big and bright, and that’s what we’re able to see from this distance,” he said.

Photographer Shannon Bileski has captured several snapshots of the comet in the last few days. She says her photos were made even better by the presence of very vibrant clouds in the upper atmosphere.

“They’re very incredible to see and I knew the spot that I wanted to hit, try to hit the comet and that’s where I went,” said Bileski, whose bucket list included photographing a comet. “Get out, see it, shoot it. It’s pretty amazing to see.”

The last time a comet of this calibre was visible from Earth was Comet Hale-Bopp in 1997, according to Young. He says Comet Neowise is not expected to re-enter our solar system for another 6,000 years.

“They could happen at any time,” said Young. “They’re very unpredictable. We don’t know where they all are, and sometimes a new discovery like this one will come out of nowhere and just surprise us.

“Astronomers have basically dropped everything they are doing to take advantage of this limited opportunity.”

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Cosmic Cataclysm Allows Precise Test of Einstein’s Theory of General Relativity – SciTechDaily

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The MAGIC telescope system at the Roque de los Muchachos Observatory, La Palma, Canary Islands, Spain. Credit: Giovanni Ceribella/MAGIC Collaboration

In 2019, the MAGIC telescopes detected the first Gamma Ray Burst at very high energies. This was the most intense gamma-radiation ever obtained from such a cosmic object. But the GRB data have more to offer: with further analyses, the MAGIC scientists could now confirm that the speed of light is constant in vacuum — and not dependent on energy. So, like many other tests, GRB data also corroborate Einstein’s theory of General Relativity. The study has now been published in Physical Review Letters.

Einstein’s general relativity (GR) is a beautiful theory that explains how mass and energy interact with space-time, creating a phenomenon commonly known as gravity. GR has been tested and retested in various physical situations and over many different scales, and, postulating that the speed of light is constant, it always turned out to outstandingly predict the experimental results. Nevertheless, physicists suspect that GR is not the most fundamental theory, and that there might exist an underlying quantum mechanical description of gravity, referred to as quantum gravity (QG).

Some QG theories consider that the speed of light might be energy dependent. This hypothetical phenomenon is called Lorentz invariance violation (LIV). Its effects are thought to be too tiny to be measured, unless they are accumulated over a very long time. So how to achieve that? One solution is using signals from astronomical sources of gamma rays. Gamma-ray bursts (GRBs) are powerful and far away cosmic explosions, which emit highly variable, extremely energetic signals. They are thus excellent laboratories for experimental tests of QG. The higher energy photons are expected to be more influenced by the QG effects, and there should be plenty of those; these travel billions of years before reaching Earth, which enhances the effect.

Gamma-Ray Burst Hits MAGIC

Artist’s impression of a gamma ray burst observed by the MAGIC telescope system and satellite observatories.
Credit: Superbossa.com and Alice Donini

GRBs are detected on a daily basis with satellite-borne detectors, which observe large portions of the sky, but at lower energies than the ground-based telescopes like MAGIC. On January 14, 2019, the MAGIC telescope system detected the first GRB in the domain of teraelectronvolt energies (TeV, 1000 billion times more energetic than the visible light), hence recording by far the most energetic photons ever observed from such an object. Multiple analyses were performed to study the nature of this object and the very high energy radiation.

Tomislav Terzić, a researcher from the University of Rijeka, says: “No LIV study was ever performed on GRB data in the TeV energy range, simply because there was no such data up to now. For over twenty years we were anticipating that such observation could increase the sensitivity to the LIV effects, but we couldn’t tell by how much until seeing the final results of our analysis. It was a very exciting period.”

Naturally, the MAGIC scientists wanted to use this unique observation to hunt for effects of QG. At the very beginning, they however faced an obstacle: the signal that was recorded with the MAGIC telescopes decayed monotonically with time. While this was an interesting finding for astrophysicists studying GRBs, it was not favorable for LIV testing. Daniel Kerszberg, a researcher at IFAE in Barcelona said: “when comparing the arrival times of two gamma-rays of different energies, one assumes they were emitted instantaneously from the source. However, our knowledge of processes in astronomical objects is still not precise enough to pinpoint the emission time of any given photon.”

Traditionally the astrophysicists rely on recognizable variations of the signal for constraining the emission time of photons. A monotonically changing signal lacks those features. So, the researchers used a theoretical model, which describes the expected gamma-ray emission before the MAGIC telescopes started observing. The model includes a fast rise of the flux, the peak emission and a monotonic decay like that observed by MAGIC. This provided the scientists with a handle to actually hunt for LIV.

A careful analysis then revealed no energy-dependent time delay in arrival times of gamma rays. Einstein still seems to hold the line. “This however does not mean that the MAGIC team was left empty-handed,” said Giacomo D’Amico, a researcher at Max Planck Institute for Physics in Munich; “we were able to set strong constraints on the QG energy scale.” The limits set in this study are comparable to the best available limits obtained using GRB observations with satellite detectors or using ground-based observations of active galactic nuclei.

Cedric Perennes, postdoctoral researcher at the university of Padova added: “We were all very happy and feel privileged to be in the position to perform the first study on Lorentz invariance violation ever on GRB data in TeV energy range, and to crack the door open for future studies!”

In contrast to previous works, this was the first such test ever performed on a GRB signal at TeV energies. With this seminal study, the MAGIC team thus set a foothold for future research and even more stringent tests of Einstein’s theory in the 21st century. Oscar Blanch, spokesperson of the MAGIC collaboration, concluded: “This time, we observed a relatively nearby GRB. We hope to soon catch brighter and more distant events, which would enable even more sensitive tests.”

Reference: “Bounds on Lorentz Invariance Violation from MAGIC Observation of GRB 190114C” by V. A. Acciari et al. (MAGIC Collaboration), 9 July 2020, Physical Review Letters.
DOI: 10.1103/PhysRevLett.125.021301

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