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How Animals May Have Conquered Snowball Earth

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Planet Earth used to be something like a cross between a deep freeze and a car crusher. During vast stretches of the planet’s history, everything from pole to pole was squashed beneath a blanket of ice a kilometer or more thick. Scientists call this snowball Earth.

Some early animals managed to endure this frigid era from roughly 720 to 580 million years ago, but they had their work cut out for them. Despite their valiant successes, the repeated expansion and contraction of giant ice sheets pulverized the hardy extremophiles’ remains leaving almost no trace of them in the fossil record and scientists with little to no idea of how they managed to survive.

“It’s basically like having a giant bulldozer,” says Huw Griffiths of the British Antarctic Survey. “The next glacial expansion would have just erased all that and turned it into mush, basically.”

Despite the lack of direct evidence thanks to all that glacial churning, Griffiths argues it is reasonable to propose that a diverse range of animal life inhabited snowball Earth. He suggests that this flourishing would have pre-dated the so-called Cambrian explosion, a period around 540 million years ago when a great and unprecedented diversity of animal life emerged on Earth. “It’s not a huge leap of imagination that there were much smaller, simpler things that existed before that,” Griffiths says.

The full picture of animal life during this time is lost, but Griffiths and his colleagues take a stab in a recent paper at trying to figure out what it might have looked like.

The team considered three different frozen periods. The first was the Sturtian snowball Earth, which began about 720 million years ago. It lasted for up to 60 million years. This is a mind-blowingly long time—it’s nearly as long as the period between the end of the dinosaur era and today. Then came the Marinoan snowball Earth, which started 650 million years ago and lasted a mere 15 million years. It was eventually followed by the Gaskiers glaciation around 580 million years ago. This third glaciation was shorter still and is often called a slushball rather than a snowball Earth because the ice coverage was likely not as extensive.

Though the ice smushed most of the fossils from these periods, scientists have found a handful of remnants. These rare fossils portray the weird animals that existed around the time of the Gaskiers glaciation. Among these ancient slushball-Earth dwellers were the frondomorphs—organisms that looked a bit like fern leaves. Frondomorphs lived fixed to the seafloor beneath the ice and possibly absorbed nutrients from the water as it flowed around them.

Short on direct evidence, Griffiths and his colleagues instead argue that the survival strategies of animals during the great freezes of the past are likely echoed by the life that dwells in the most similar environment on Earth today—Antarctica.

Many animals, such as sea stars and sponges, eke out an existence on the seafloor beneath the ice off Antarctica. Photo by Norbert Wu/Minden Pictures

Some modern Antarctic inhabitants such as anemones live upside down affixed to the underside of the sea ice. One of the favorite feeding strategies of krill is grazing microorganisms on this upturned plane. Perhaps early animals foraged and found shelter in such locations, too, Griffiths and his colleagues suggest.

It’s also possible that the waxing and waning of sea ice introduced algae or other microorganisms living on the ice into seawater allowing them to bloom, which might have provided food for other early animals.

One of the challenges that inhabitants of a snowball Earth faced was the possible lack of oxygen, both because the oxygen levels in the air were low and because there was limited mixing from the atmosphere into the water. But oxygenated meltwater high in the water column might have supported animals that depended on it. Some denizens that live on the Antarctic seafloor today, such as certain species of feather star, solve this problem by relying on water currents to bring a steady flow of oxygen and nutrients from the small areas of open water at the surface to deep below the ice shelves. There’s no reason to think this didn’t happen during the Gaskiers slushball Earth period, too.

“We are really talking about very basic forms of life … but at the time that’s all you’d have needed to be king of the animals,” says Griffiths.

Alongside frondomorphs, the seafloor might also have been inhabited by sponges. Some fossil evidence of sponges dates back to well before the Sturtian snowball Earth, though there is some debate over this, says Griffiths.

Ashleigh Hood, a sedimentologist at the University of Melbourne in Australia who was not involved in the research, jokes that “everyone, including us, has their oldest sponge that they’ve found in the record and no one else believes them.”

Some modern sponges live symbiotically with bacteria, which may help them access nutrients when other food is scarce. “That’s probably based off a survival strategy they had really early on in their history,” Hood suggests.

Andrew Stewart, assistant curator at the Museum of New Zealand Te Papa Tongarewa who also wasn’t involved in the paper, has studied countless species from harsh Antarctic environments. Many of these organisms cope in incredibly dark, cold, or chemically toxic places. For Stewart, Antarctic extremophiles are a reminder of how robust life on Earth really is—and perhaps always has been.

“It’s just the most amazing place,” he says. “You go, No, bollocks, nothing can survive there! Well, actually it can.”

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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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