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Nunavut's ancient Qikiqtania fish fossil helps shed new light on evolution – CBC.ca

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Nunavut’s rich fossil record has a new star, the roughly 365-million-year-old Qikiqtania Wakei.

It was named after the Qikiqtani region of Nunavut, where it was found, and the late David Wake, an acclaimed evolutionary biologist.

“Some of the fossils that are coming out of Ellesmere Island and northern Canada are so important for how we as scientists and people in general understand this period of life on earth,” said Tom Stewart, an assistant professor at Penn State, who recently reported about Qikiqtania in the journal Nature.

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Millions of years back, it was a different world: When Qikiqtania lived in the polar region, the now-treeless land would have resembled today’s Amazon River delta.

Tom Stewart, assistant professor at Penn State, looks at the fossils of Qikiqtania. (Stephanie Sang)

In its waters were fish, some of which had started to move on to the land.

But, among those fish which left behind fossil traces, Qikiqtania has revealed itself to be a new creature.

“It’s exciting for a few reasons,” Stewart said.

They knew Qikiqtania was new and “also something very unusual,” he said.

“From a first impression, we could tell this was an animal that is closely related to the first animals that had fingers and toes. “

But Qikiqtania’s fins showed it was quite different from those first animals.

That’s because they didn’t see any muscles which would have needed to be move onto land.

“It was doing something very different. This fish was not [out of the water.] We think this was the evolution of a fish that used to live on the ground,” he said.

Looking at animals today, Stewart said it’s not “so crazy” to think of a fish transitioning from water to land or back and forth over time.

A portrait of a man pointing into the broad landscape around him.
Neil Shubin, professor of Organismal Biology and Anatomy at the University of Chicago, stands in Ellesmere Island where he discovered both the Qikiqtania and Tiktaalik fossils days apart in 2004. (Edward Daeschler)

Some frogs also live wholly in the water, while others live mainly on the land, he said.

But to see a similar dynamic taking place so long ago, through Qikiqtania, was “really exciting and unexpected for us,” Stewart said.

But the revelation wasn’t immediate.

It started on a 2004 trip to Ellesmere near the eastern arm of Bird Fiord, where Neil Shubin, now at the University of Chicago, had picked up the fossil, which was lying exposed on the ground.

Members of the team would walk on the rocks on hillsides looking for a particular colour or texture that might indicate a fossil.

In the case of Qikiqtania, the scales of the fish were white and they had bumps on them, so they knew there was a fossil.

In 2004, the fossil was bundled up and taken south, along with hundreds of others, for painstaking study.

Finally two years ago, Stewart and his team brought the fossil to Shubin’s laboratory for a CT scan.

“We could look inside the fossil and see a whole lot of preserved parts of the animal that we didn’t know existed,” said Stewart, adding it was new but “also something very unusual.”

Pieces of the fish's fossils, including its jaw and scales are laid out in a row.
This image shows the preserved jaws and scales from the Qikiqtania fossil. (Tom Stewart)

Fossils of an ancient fish species Tiktaalik roseae were also found during that 2004 trip to Ellesmere.

Tiktaalik is one of the best-known ancient transitional species between fish and land-dwelling tetrapods, or animals with two pairs of limbs.

Both Qikiqtania and Tiktalik will remain at the Nunavut fossil collection of the Canadian Museum of Nature in Ottawa until a museum facility can welcome them home.

Research on Qikiqtani took place thanks to people in Resolute Bay and Grise Fiord, the Iviq Hunters and Trappers of Grise Fiord, and Nunavut’s Department of Heritage and Culture.

To them— and on behalf of the entire research team, Stewart said “nakurmiik.”

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Solar Storm That Caused Dazzling Auroral Display Could Linger

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(Bloomberg) — A brilliant display of northern lights touched off by a massive geomagnetic storm was visible to a wide swath of the world Friday, and the aurora could linger through Saturday in many places if the weather is clear.

Red, purple and green streamers of the aurora borealis dazzled viewers in North America on Friday and were seen much farther south than normal, with people in California, Arizona and Texas reporting they could see it, according to AccuWeather, Inc. Typically, the spectacular display is only visible in northern locales like Alaska, North Dakota, Canada and Iceland.

The display was touched off by a severe geomagnetic storm that peaked about 12:04 a.m. Friday, according to the US Space Weather Prediction Center, and if the weather is clear, more could be in store on Saturday.

A coronal mass ejection, an explosion of magnetic fields and plasma from the sun’s atmosphere, hit Earth early Friday with more force than initially forecast. These events can disrupt Earth’s magnetic field causing auroral displays, as well as disrupting satellites, communication and electric grids.

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Read more: A Swedish Resort Lets You See the Northern Lights From Your Room

The US Space Weather Prediction Center had originally expected a G2 level storm Friday on its five-step scale, the event measured in at G4, one of the strongest triggered on Earth since 2017.

In addition to the dazzling auroral displays, a G4 storm can cause headaches for power grid operators and force spacecraft to adjust their orbits. The storm can also degrade satellite navigation, radio broadcasts and even cause pipelines to build up an electric charge. In early 2022, Elon Musk’s SpaceX lost 40 Starlink satellites because of a solar storm.

The impacts from the coronal mass ejection have trailed off, but energy coming from what scientists call a “coronal hole” will continue at least through Saturday and that could mean the aurora could be seen by viewers across Europe, Asia and North America through Sunday, the UK Met Office said on its website.

There are currently eight sunspot clusters visible on the side of the sun facing Earth, however another coronal mass ejection blasting toward us isn’t forecast, the UK Met Office said.

 

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An airplane-sized asteroid will pass between the Earth and moon’s orbits Saturday

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An asteroid dubbed “city killer” for its size will pass harmlessly between the moon and the Earth Saturday evening.

The asteroid 2023 DZ2 will pass at a distance of over 100,000 miles, less than half the distance between the Earth and the moon. It’s about 160 feet long — about the size of an airliner. An asteroid that size could cause significant damage if it hit a populated area, hence its nickname.

“While close approaches are a regular occurrence, one by an asteroid of this size (140-310 ft) happens only about once per decade, providing a unique opportunity for science,” NASA Asteroid Watch tweeted.

Astronomers from the International Asteroid Warning Network, established about 10 years ago to coordinate international responses to potential near-Earth object impact threats, will be monitoring and learning from this asteroid.

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NASA Asteroid Watch called the opportunity “good practice” in case “a potential asteroid threat were ever discovered.”

Near-Earth objects are asteroids or comets that pass close to the Earth’s orbit, and they generally come from objects that are affected by other planets’ gravity, moving them into orbits that push them close to Earth, according to the United Nations Office for Outer Space Affairs.

The European Space Agency maintains a risk list of 1,460 objects, which catalogs every object with a non-zero chance of hitting Earth over the next 100 years. Asteroid 2023 DZ2, which is in orbit around the sun, is not on the risk list.

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Large asteroid to zoom between Earth and Moon

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On Saturday, the 2023DZ2 will come within a third of the distance from the Earth to the Moon.

A large asteroid will safely zoom between Earth and the Moon on Saturday, a once-in-a-decade event that will be used as a training exercise for planetary defence efforts, according to the European Space Agency.

The asteroid, named 2023 DZ2, is estimated to be 40 to 70 metres (130 to 230 feet) wide, roughly the size of the Parthenon, and big enough to wipe out a large city if it hit our planet.

At 19:49 GMT on Saturday, it will come within a third of the distance from the Earth to the Moon, said Richard Moissl, the head of the ESA’s planetary defence office.

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Though that is “very close”, there is nothing to worry about, he told AFP news agency.

Small asteroids fly past every day, but one of this size coming so close to Earth only happens about once every 10 years, he added.

The asteroid will pass 175,000km (109,000 miles) from Earth at a speed of 28,000 kilometres per hour (17,400 miles per hour). The Moon is roughly 385,000km (239,228 miles) away.

An observatory in La Palma, one of Spain’s Canary Islands, first spotted the asteroid on February 27.

Last week, the United Nations-endorsed International Asteroid Warning Network decided it would take advantage of the close look, carrying out a “rapid characterisation” of 2023 DZ2, Moissl said. That means astronomers around the world will analyse the asteroid with a range of instruments such as spectrometers and radars.

The goal is to find out just how much we can learn about such an asteroid in only a week, Moissl said. It will also serve as training for how the network “would react to a threat” possibly heading our way in the future, he added.

The asteroid will again swing past Earth in 2026, but poses no threat of impact for at least the next 100 years – which is how far out its trajectory has been calculated.

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