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'Frozen in place' fossils reveal dinosaur-killing asteroid struck in spring – Livescience.com

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Spring is a time for budding flowers, tender green leaves and baby animals. But 66 million years ago, that gentle season instead brought mass death and carnage from Earth’s catastrophic impact with a massive space rock.

Earth was forever changed after an enormous asteroid smashed into our planet at the end of the Cretaceous period (145 million to 66 million years ago), triggering a global extinction that wiped out 76% of life on Earth, including all nonavian dinosaurs, pterosaurs and most marine reptiles. Scientists recently pinpointed the season of the disaster and linked it to springtime in the Northern Hemisphere, after analyzing fossilized animals that died minutes after the impact.

They found the fossils at a site called Tanis, where a river once flowed through what is now North Dakota. After the asteroid struck near Mexico’s Yucatán Peninsula, the shock sent powerful waves roaring upstream toward Tanis, sweeping up fish and forest creatures and burying them alive under layers of soil. When the water subsided, it left behind an astonishingly well preserved 3D snapshot of destruction, captured within 30 minutes after the asteroid struck, the researchers reported in a new study. Fossils of those filter-feeding fish also held clues about their seasonal growth cycles, hinting that spring had sprung when the fish died and the dinosaurs‘ reign abruptly ended.

Related: The 5 mass extinction events that shaped the history of Earth

The moment of mass, instantaneous death preserved in Tanis, with broken and splintered fish fossils wrapped around tree branches and strewn in all directions, “was like the worst car crash you’ve ever seen, frozen in place,” said lead study author Melanie During, a doctoral candidate in the Department of Organismal Biology at Uppsala University in Sweden. It was also “the most spectacular deposit I’ve ever seen in my life,” During said at a news conference on Feb. 22.

During excavated Cretaceous fish at Tanis in August 2017, spending two weeks digging out fossils of paddlefish and sturgeons. Fish skeletons — even after fossilizing — retain records of an animal’s growth, which depends on seasonal food availability. By mapping these patterns in bone cell growth and density, the scientists hoped to identify which part of the growth cycle the Tanis fish had reached when they died, which could indicate what time of year it was.

The study authors scanned the fossils using synchrotron X-ray imaging, nondestructively imaging and reconstructing the fossils in 3D. They found tiny glass balls called spherules embedded in the fishes’ gills; these small spheres fused from ultrahot sediments when the asteroid struck and ejected towering plumes of dirt from the impact crater. Particles flew into Earth’s atmosphere and beyond and then rained back down on the planet as glassy beads. 

An impact spherule from the Tanis event deposit. (Image credit: During et al. (2022))

Other researchers who studied Tanis’ Cretaceous death pit calculated that impact spherules would have fallen between 15 and 30 minutes after the asteroid crashed into Earth. Because spherules were in the fishes’ gills but had not been swallowed, the fish were likely buried alive immediately after inhaling the glassy beads — within 30 minutes after the asteroid impact, according to the new study.   

Related: Photos: The freakiest-looking fish

Synchrotron scans also revealed signs of cell growth fluctuations in the fossilized bones, taking place over seven years. Much as trees mark the passage of time in the accumulation of rings, which are visible in cross sections of their trunks, fish add layers to their bones as they age, with growth peaking by the end of the summer and then declining over the winter. When the fish died, they were just entering a time of significant bone growth — which coincided with spring, study co-author Dennis Voeten, a research engineer at Uppsala University’s Department of Organismal Biology, said at the news conference.

“I think it makes sense to everyone that when a fish eats, its bone grows,” During told Live Science in an email. However, seeing this quantified in Cretaceous fossils “is really new and unbelievably informative for future studies,” she said.

A paddlefish from Tanis, prior to a scan at the European Synchrotron Radiation Facility in Grenoble, France. (Image credit: During et al. (2022))

Records of carbon isotopes, or variations of the element carbon, from one of the fishes further confirmed that the fish died in springtime, the scientists wrote in the study. Like bone growth, “the carbon isotope record shows a distinct cyclic pattern, where high values reflect high productivity of plankton,” which was the main food for paddlefish, said study co-author Jeroen van der Lubbe, an assistant professor in the Department of Earth Sciences at the Vrije Universiteit Amsterdam in the Netherlands. Plankton abundance is typically highest in summer; the isotope analysis showed that plankton productivity hadn’t yet peaked for the year, so the researchers concluded that the fish perished in the spring, van der Lubbe said at the news conference.

The timing of the asteroid impact likely had far-reaching consequences, with some species on Earth being better equipped to weather the disaster simply because of what season it was in their part of the world, the researchers reported. 

Organisms in the Northern Hemisphere, where spring was warming things up, were likely just emerging and were primed for growth and reproduction after the cold winter months. They would have been exposed and had fewer resources, having already depleted whatever stored reserves helped them survive the winter. A springtime ecosystem could therefore have been more vulnerable to the immediate effects of the impact than plants and animals in the Southern Hemisphere that were hunkering down for winter, During said.

“After the impact, a sudden cooling of unknown duration took place — which, of course, had its own influence on the extinction pattern,” During said. “Nevertheless, it is clear that the organismal groups that did not survive that catastrophic spring/autumn would not have been around to fight in the subsequent nuclear winter to begin with.” 

The findings were published online Wednesday (Feb. 23) in the journal Nature.

Originally published on Live Science.

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Here’s how Helene and other storms dumped a whopping 40 trillion gallons of rain on the South

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More than 40 trillion gallons of rain drenched the Southeast United States in the last week from Hurricane Helene and a run-of-the-mill rainstorm that sloshed in ahead of it — an unheard of amount of water that has stunned experts.

That’s enough to fill the Dallas Cowboys’ stadium 51,000 times, or Lake Tahoe just once. If it was concentrated just on the state of North Carolina that much water would be 3.5 feet deep (more than 1 meter). It’s enough to fill more than 60 million Olympic-size swimming pools.

“That’s an astronomical amount of precipitation,” said Ed Clark, head of the National Oceanic and Atmospheric Administration’s National Water Center in Tuscaloosa, Alabama. “I have not seen something in my 25 years of working at the weather service that is this geographically large of an extent and the sheer volume of water that fell from the sky.”

The flood damage from the rain is apocalyptic, meteorologists said. More than 100 people are dead, according to officials.

Private meteorologist Ryan Maue, a former NOAA chief scientist, calculated the amount of rain, using precipitation measurements made in 2.5-mile-by-2.5 mile grids as measured by satellites and ground observations. He came up with 40 trillion gallons through Sunday for the eastern United States, with 20 trillion gallons of that hitting just Georgia, Tennessee, the Carolinas and Florida from Hurricane Helene.

Clark did the calculations independently and said the 40 trillion gallon figure (151 trillion liters) is about right and, if anything, conservative. Maue said maybe 1 to 2 trillion more gallons of rain had fallen, much if it in Virginia, since his calculations.

Clark, who spends much of his work on issues of shrinking western water supplies, said to put the amount of rain in perspective, it’s more than twice the combined amount of water stored by two key Colorado River basin reservoirs: Lake Powell and Lake Mead.

Several meteorologists said this was a combination of two, maybe three storm systems. Before Helene struck, rain had fallen heavily for days because a low pressure system had “cut off” from the jet stream — which moves weather systems along west to east — and stalled over the Southeast. That funneled plenty of warm water from the Gulf of Mexico. And a storm that fell just short of named status parked along North Carolina’s Atlantic coast, dumping as much as 20 inches of rain, said North Carolina state climatologist Kathie Dello.

Then add Helene, one of the largest storms in the last couple decades and one that held plenty of rain because it was young and moved fast before it hit the Appalachians, said University of Albany hurricane expert Kristen Corbosiero.

“It was not just a perfect storm, but it was a combination of multiple storms that that led to the enormous amount of rain,” Maue said. “That collected at high elevation, we’re talking 3,000 to 6000 feet. And when you drop trillions of gallons on a mountain, that has to go down.”

The fact that these storms hit the mountains made everything worse, and not just because of runoff. The interaction between the mountains and the storm systems wrings more moisture out of the air, Clark, Maue and Corbosiero said.

North Carolina weather officials said their top measurement total was 31.33 inches in the tiny town of Busick. Mount Mitchell also got more than 2 feet of rainfall.

Before 2017’s Hurricane Harvey, “I said to our colleagues, you know, I never thought in my career that we would measure rainfall in feet,” Clark said. “And after Harvey, Florence, the more isolated events in eastern Kentucky, portions of South Dakota. We’re seeing events year in and year out where we are measuring rainfall in feet.”

Storms are getting wetter as the climate change s, said Corbosiero and Dello. A basic law of physics says the air holds nearly 4% more moisture for every degree Fahrenheit warmer (7% for every degree Celsius) and the world has warmed more than 2 degrees (1.2 degrees Celsius) since pre-industrial times.

Corbosiero said meteorologists are vigorously debating how much of Helene is due to worsening climate change and how much is random.

For Dello, the “fingerprints of climate change” were clear.

“We’ve seen tropical storm impacts in western North Carolina. But these storms are wetter and these storms are warmer. And there would have been a time when a tropical storm would have been heading toward North Carolina and would have caused some rain and some damage, but not apocalyptic destruction. ”

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Follow AP’s climate coverage at https://apnews.com/hub/climate

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Follow Seth Borenstein on Twitter at @borenbears

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Associated Press climate and environmental coverage receives support from several private foundations. See more about AP’s climate initiative here. The AP is solely responsible for all content.

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‘Big Sam’: Paleontologists unearth giant skull of Pachyrhinosaurus in Alberta

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It’s a dinosaur that roamed Alberta’s badlands more than 70 million years ago, sporting a big, bumpy, bony head the size of a baby elephant.

On Wednesday, paleontologists near Grande Prairie pulled its 272-kilogram skull from the ground.

They call it “Big Sam.”

The adult Pachyrhinosaurus is the second plant-eating dinosaur to be unearthed from a dense bonebed belonging to a herd that died together on the edge of a valley that now sits 450 kilometres northwest of Edmonton.

It didn’t die alone.

“We have hundreds of juvenile bones in the bonebed, so we know that there are many babies and some adults among all of the big adults,” Emily Bamforth, a paleontologist with the nearby Philip J. Currie Dinosaur Museum, said in an interview on the way to the dig site.

She described the horned Pachyrhinosaurus as “the smaller, older cousin of the triceratops.”

“This species of dinosaur is endemic to the Grand Prairie area, so it’s found here and nowhere else in the world. They are … kind of about the size of an Indian elephant and a rhino,” she added.

The head alone, she said, is about the size of a baby elephant.

The discovery was a long time coming.

The bonebed was first discovered by a high school teacher out for a walk about 50 years ago. It took the teacher a decade to get anyone from southern Alberta to come to take a look.

“At the time, sort of in the ’70s and ’80s, paleontology in northern Alberta was virtually unknown,” said Bamforth.

When paleontogists eventually got to the site, Bamforth said, they learned “it’s actually one of the densest dinosaur bonebeds in North America.”

“It contains about 100 to 300 bones per square metre,” she said.

Paleontologists have been at the site sporadically ever since, combing through bones belonging to turtles, dinosaurs and lizards. Sixteen years ago, they discovered a large skull of an approximately 30-year-old Pachyrhinosaurus, which is now at the museum.

About a year ago, they found the second adult: Big Sam.

Bamforth said both dinosaurs are believed to have been the elders in the herd.

“Their distinguishing feature is that, instead of having a horn on their nose like a triceratops, they had this big, bony bump called a boss. And they have big, bony bumps over their eyes as well,” she said.

“It makes them look a little strange. It’s the one dinosaur that if you find it, it’s the only possible thing it can be.”

The genders of the two adults are unknown.

Bamforth said the extraction was difficult because Big Sam was intertwined in a cluster of about 300 other bones.

The skull was found upside down, “as if the animal was lying on its back,” but was well preserved, she said.

She said the excavation process involved putting plaster on the skull and wooden planks around if for stability. From there, it was lifted out — very carefully — with a crane, and was to be shipped on a trolley to the museum for study.

“I have extracted skulls in the past. This is probably the biggest one I’ve ever done though,” said Bamforth.

“It’s pretty exciting.”

This report by The Canadian Press was first published Sept. 25, 2024.

The Canadian Press. All rights reserved.

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The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

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TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.

Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.

Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.

The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.

The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.

It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.

Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.

Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.

Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.

Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.

Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.

The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”

The Canadian Press. All rights reserved.

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