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New prehistoric plant discovery highlights the unexpected diversity of non-flowering plants – The Conversation

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The renowned Apple Bay fossil locality of northern Vancouver Island is helping us reimagine seed plant diversity in the Early Cretaceous, the last of three geologic periods comprising the Mesozoic Era.

Until recently, it was assumed that most major lineages of seed plants had been recognized in the fossil record. Their evolution and relationships to one another are still being debated, but few botanists believed that we might still be missing wide swathes of vascular plant diversity.

Using fossils from this site, my colleagues (paleobotanists Gar Rothwell and Ruth Stockey) and I have been challenging the assumption that the plant fossil record is largely complete. Our recent discovery of a new genus of non-flowering seed plants illustrates that researchers’ understanding of seed plant diversity in the Cretaceous is by no means complete.

Exceptionally detailed fossilization

In Apple Bay, sandstone and siltstone beds tilt gently up, variably exposed with every falling tide, and giving few clues as to their scientific significance. This site is a konservat lagerstätte: a fossil locality with exceptional preservation.

During the Early Cretaceous (about 136 million years ago), seasonal storms and flooding events swept vegetation out into a marine basin. Plant debris rapidly settled and fossilized at a cellular level of detail. This type of fossilization is called permineralization.

Permineralized plants offer a wealth of anatomical information, enabling us to ascertain features of plant development, organography (the arrangement of plant organs) and reproduction — data critical for understanding plant evolution. In the two decades we’ve been studying Apple Bay, it has become apparent that this site contains the most comprehensive record of terrestrial vegetation immediately prior to the evolution and radiation of angiosperms (flowering plants).

Flower power

A mere five to 10 million years after the Apple Bay flora settled into marine sediments, angiosperms were becoming abundant in the fossil record. Through the Late Cretaceous, they came to dominate terrestrial landscapes.

Prevailing narratives in plant biology suggest angiosperms out-competed other seed plants. Perhaps angiosperms were more adaptive to changing climate; used nutrients more effectively; or gymnosperms — non-flowering seed plants — were already in decline by the Early Cretaceous, enabling angiosperms to opportunistically occupy newly available niche space.

Welwitschia mirabilis, a type of non-flowering seed plant, in the Namibian desert.
(Shutterstock)

The vast majority of seed plants that have ever lived are now extinct. The gymnosperms that are still alive are themselves relics of a much greater fossil diversity, and many major lineages of seed plants are known only from the fossil record. The permineralized plants of Apple Bay demonstrate that seed plants were even more diverse throughout the Cretaceous than botanists had previously realized.

Gymnosperms are well-represented in the Apple Bay flora. They include conifers and gnetophytes, which still have living exemplars like Welwitschia. They also include bennettitalean and doylealean plants, which represent wholly extinct orders. Indeed, the extinct Doyleales were first described from Apple Bay in 2009, and have subsequently been found in Mongolia as well.

Plant discovery

The new plant, Xadzigacalix quatsinoensis, probably also represents yet another order of extinct plants. The name is a nod to Kwak̓wala-speaking First Nations — the Apple Bay locality occurs within traditional and unceded territory of the Quatsino First Nation. Xadzigacalix derives from xa̱dziga, a Kwak̓wala word for plant resin, and calix, which is Latin for chalice. The name reflects the resinous, fleshy cupule that surrounds and protected the seeds of the Xadzigacalix plant.

The seeds of this plant have complex three-layered seed coats and were produced at the tip of a woody stem. A cupule encloses most of the seed, except for a narrow tube through which the embryo would have been pollinated. This organography, along with anatomical features like vascular tissue that are observable at a cellular level, constitute a novel combination of features not found in any other lineage of plants.

It’s not yet clear which group of seed plants actually gave rise to the angiosperms. Xadzigacalix likely represents a new order of seed plants, perhaps distantly related to gnetophytes or angiosperms. While research in plant molecular systematics (a discipline that uses genetic data to understand plant relatioships) has resolved most evolutionary relationships within flowering plants, their origins and nearest relatives remain mysterious.

a cross section of a fossilised plant structure

A fossilized seed and cupule of Xadzigacalix quatsinoensis.
(Az Klymiuk), Author provided

Part of this problem is that the group of seed plants most closely related to angiosperms is almost certainly extinct. Several major groups of cupulate Mesozoic gymnosperms, sometimes called corystosperms or seed ferns, have been suggested as possible relatives of angiosperms. The Xadzigacalix plant is yet another possible contender to the broader “family tree” of flowering plants.

Perplexing origins

Our assessment of the evolutionary context of the Xadzigacalix plant led us to re-evaluate the other groups of plants frequently suggested as angiosperm relatives. Throughout the Mesozoic, many seed plants “experimented” with an array of different seed-enclosing structures.

We examined whether these cupulate structures are developmentally derived from leaf or shoot tissues. Across all Mesozoic seed plants, cupules appear to be a case of evolutionary convergence, where different seed plants independently evolved similar features. It’s by no means clear if the cupules of any group are genuinely similar to the carpels — the female organs — of flowering plants.

I believe the reason angiosperm origins remain perplexing is that we still stand to discover the entirety of Mesozoic plant diversity. Our discovery of Xadzigacalix hints at how much there is is left to learn.

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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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