THe Sherassic Park - A PaLeontologic adventure

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Alaska’s Frigid North Slope Was Once a Lush, Wet, Dinosaur Hotspot, Fossils Reveal​

Conditions north of the Arctic Circle, where dinosaurs roamed in abundance during the mid-Cretaceous, were warmer than today, with rainfall comparable to “modern-day Miami”

Christian Thorsberg Daily Correspondent
March 20, 2024

Boreal forests, spongy tundra and perpetual sunshine mark summertime in Alaska’s North Slope—the state’s northernmost region, which borders the Arctic Ocean. And when autumn comes, the landscape transforms into a snow-covered darkness, a harsh place endured throughout winter and spring by both people and wildlife.

But 100 million years ago, the dinosaurs roaming this region didn’t have to contend with the frigid conditions of present-day Alaska, according to a study published in late January in the journal Geosciences. Instead, the researchers say, mid-Cretaceous Alaskan climates were warmer, rich in groundwater and more reminiscent of today’s tropics than the Arctic, at least in terms of rainfall.


Scientists uncovered a large swath of fossilized dinosaur tracks, plants, feces and tree trunks in the foothills of the DeLong Mountains along the Kukpowruk River in the state’s northwest—well within the Arctic Circle. From these preserved remains, the team of paleontologists and geologists could construct a picture of the mid-Cretaceous climate and dinosaur life.

“We were at a spot where we eventually realized that for at least 400 yards, we were walking on an ancient landscape,” study co-author Anthony Fiorillo, formerly a paleontologist at Southern Methodist University and now executive director of the New Mexico Museum of Natural History and Science, says in a statement. “We found large upright trees with little trees in between and leaves on the ground. We had tracks on the ground and fossilized feces… It was just like we were walking through the woods of millions of years ago.”

A ten-centimeter-wide theropod track found along the banks of the Kukpowruk River. Anthony Fiorillo

Researchers analyzed rocks, preserved logs and plant material, learning the area was once a network of rivers or deltas and floodplains. Fossilized tree stumps, some as wide as two feet in diameter, hinted at a former thick forest.

The site was also “crazy rich with dinosaur footprints,” says Fiorillo in the statement. Roughly 75 fossil tracks indicate the relatively warm area supported plant-eating and carnivorous dinosaurs, and it likely attracted prehistoric birds, which made 15 percent of the tracks.


Additionally, the warm, wet paleoclimate received up to 70 inches of precipitation annually. “The samples we analyzed indicate it was roughly equivalent to modern-day Miami,” Fiorillo adds in the statement.

The research was focused at and near the Nanushuk Formation, an outcrop of sedimentary rock between 94 million and 113 million years old—which, crucially, formed around the same time as an early version of the Bering Land Bridge connecting Asia and North America.

Almost every Cretaceous Period dinosaur that eventually lived in what came to be the American Southwest crossed that land bridge, the team told High Country News’ Emily Schwing in September. Studying the prehistoric creatures’ Alaska range, they say, helps shed light on their cross-continental journey.

But some of the greatest insights from the study are the clues it offers into ancient climates.

“The tracks are interesting, but I think the more important information in the paper is that there’s a geochemical record of high rainfall and fossils of decent-sized trees,” Matthew Carrano, a research geologist and Dinosauria curator at the Smithsonian’s National Museum of Natural History, tells Smithsonian magazine in an email.

While the polar region received varying amounts of sunlight throughout the year in the Cretaceous, similar to today, the findings show the weather was more consistently warmer and wet. How the region’s flora and fauna survived, the authors suggest in the statement, may offer clues into our climate-changing present and future, with the Arctic warming as much as four times faster than the rest of the world.

“Given that we have no similar ecosystems today, this is important because it provides us with a past window into times when increased global warmth permitted very different environments near the poles,” Carrano says.

For the team, this fossil site is a new jumping-off point for further research into the dynamics of the Cretaceous Arctic.

“I keep saying it’s like going to the candy store,” Fiorillo told High Country News. “Someone opened the door and here [the dinosaurs] are.”

https://www.smithsonianmag.com/smar...et-dinosaur-hotspot-fossils-reveal-180983990/

 

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Fossil of ‘largest snake to have ever existed’ found in western India​

Scientists estimate Vasuki indicus was up to 15m long, weighed a tonne and would have constricted its prey

Some of the vertebrae discovered in Gujarat, the largest of which was about 11cm wide. Photograph: AP

Fossil vertebrae unearthed in a mine in western India are the remains of one of the largest snakes that ever lived, a monster estimated at up to 15 metres in length – longer than a T rex.

Scientists have recovered 27 vertebrae from the snake, including a few still in the same position as they would have been when the reptile was alive. They said the snake, which they named Vasuki indicus, would have looked like a large python and would not have been venomous.

The lignite mine where the fossil was found is located in Panandhro, in the western state of Gujarat.

“Considering its large size, Vasuki was a slow-moving ambush predator that would subdue its prey through constriction like anacondas and pythons. This snake lived in a marshy swamp near the coast at a time when global temperatures were higher than today,” said Debajit Datta, a postdoctoral researcher in palaeontology at the Indian Institute of Technology Roorkee and the lead author of the study, published in the journal Scientific Reports on Thursday.

Because of the incomplete nature of the Vasuki remains, the researchers gave an estimated length range of 11-15 metres and 1 tonne in weight.


Vasuki, named after the snake king associated with the Hindu deity Shiva, rivals in size another huge prehistoric snake called Titanoboa, whose fossils were discovered in a coalmine in northern Colombia in 2009. Titanoboa, estimated at 13 metres long and more than 1 tonne, lived between 58m and 60m years ago. The largest living snake today is Asia’s reticulated python at 10 metres.

“The estimated body length of Vasuki is comparable to that of Titanoboa, although the vertebrae of Titanoboa are slightly larger than those of Vasuki. However, at this point, we cannot say if Vasuki was more massive or slender compared to Titanoboa,” said Sunil Bajpai, a palaeontologist, professor at Roorkee and the study’s co-author.

These huge snakes lived during the Cenozoic era, which began after the dinosaur age ended 66m years ago.

The biggest Vasuki vertebra was about 11cm (4in) wide. Vasuki appears to have had a broad, cylindrical body perhaps around 44cm wide. The skull was not found.

“Vasuki was a majestic animal,” Datta said. “It may well have been a gentle giant, resting its head on a high porch formed by coiling its massive body for most parts of the day or moving sluggishly through the swamp like an endless train.”

The researchers are unsure what prey Vasuki ate, but considering its size it could have included crocodilians. Other fossils found in the area included crocodilians and turtles, as well as fish and two primitive whales, Kutchicetus and Andrewsiphius.

Vasuki was a member of the madtsoiidae snake family that appeared roughly 90m years ago but went extinct about 12,000 years ago. These snakes spread from India through southern Eurasia and into north Africa after the Indian subcontinent collided with Eurasia about 50m years ago, Bajpai said.

This was a dominant snake family during the dinosaur age’s late stages and into the early Cenozoic before its diversity dropped, he added.

“Snakes are amazing creatures that often leave us stunned because of their size, agility and deadliness,” Datta said. “People are scared of them as some snakes are venomous and have a fatal bite. But snakes perhaps attack people out of fear rather than with an intent to attack. I believe snakes, like most animals, are peaceful creatures, and an important component of our ecosystem.”

https://www.theguardian.com/environment/2024/apr/18/fossils-largest-snake-found-western-india