The Extinction of a Dinosaur: A Dramatic Transformation of Earth’s Landscape

Large dinosaurs such as Titanosaurus significantly influenced their ecosystems

Christian Jegou/Science Photography Library

The extinction of dinosaurs had profound consequences for Earth, leading to significant alterations in the planet’s landscapes, including shifts in river systems.

There is a clear distinction between various rock formations in North America before and after the end of the dinosaurs during the Cretaceous-Paleogene (K-PG) extinction event approximately 66 million years ago, triggered by the Chicxulub asteroid impact in the Yucatan Peninsula.

For example, the Green Gray Mudstone, recognized as the Hell Creek Formation from the dinosaur period, transitions into the more vivid pajama-striped layers of the Fort Union Formation, which hosts many lignite-rich charcoals from plant material that surfaced with the rise of mammals.

This transition was initially attributed to the direct impacts of asteroid strikes, such as increased rainfall. However, Luke Weaver from the University of Michigan and his team propose another explanation.

They examined floodplain areas in the western United States, revealing abrupt geological changes around the K-PG boundary, particularly in the Williston Basin, stretching across parts of Wyoming, Montana, and the Dakotas.

The multifaceted colorful layers from the Post-dinosaur period are believed to be deposits formed by rising water levels, creating temporary ponds. However, Weaver and his colleagues did not find supporting literature on water level changes during this era.

“There’s no evidence of extremely high water tables or particularly wet conditions,” he says. While there was an intrusion of seawater inland, the nearest instance occurred at least 300,000 years after the K-PG boundary.

Weaver’s team argues that significant sandstone layers formed post-K-PG boundary are indicative of large, stable rivers, known as Point Bar deposits, instead of temporary pond deposits. These layers can exceed 10 meters in thickness, reflecting the stability of these rivers.

Researchers attribute these findings to the extinction of dinosaurs. They propose that, like today’s large herbivores, dinosaurs were ecological engineers, disrupting vegetation, trampling, and grazing seedlings, inhibiting new plant growth.

“These creatures were colossal compared to modern fauna,” Weaver notes. For instance, while a contemporary elephant weighs around 5,000 kilograms, a Triceratops could weigh at least double that.

As they moved through and destroyed vegetation, the rivers would have flooded periodically instead of winding through forests. This change ultimately led to the expansion of marshy mudstone, according to Weaver. Once the dinosaurs vanished, tree roots stabilized the sediments, allowing water to flow through a meandering riverbed, thus creating point bars.

“This illustrates a landscape where biology plays a crucial role,” Weaver observes. Animals, he argues, significantly modify their environments, much like humans have drastically altered Earth’s landscapes.

Christopher Doughty from Northern Arizona University believes this perspective better explains the observed geological transformations than earlier theories. “In contemporary studies where large animals are removed from ecosystems, tree cover significantly increases,” he mentions. “With the extinction of dinosaurs, there were no longer large animals capable of uprooting trees. This led to a decrease in herbivory and reduced the disturbance of seedlings giving rise to robust tree growth.”

However, Cat Schroder from the University of New Mexico remains skeptical. “While there seems to be a correlation between large dinosaurs and open nutritional landscapes, causality hasn’t been established yet,” she says. “Forests thrived before, during, and after the age of dinosaurs.”

Doughty is using isotopic analysis of fossil leaves to investigate how forest structures have shifted since the dinosaurs went extinct.

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Source: www.newscientist.com

Astronomers Observe Dramatic Galaxy Collision 11 Billion Light-Years Away

Analysis from the ESO’s Very Large Telescope (VLT) and ALMA data indicates that intense radiation from a quasar within these galaxies affects the gas properties of other galaxies, reducing their ability to form new stars.



Artistic impression of a galaxy merger where the right galaxy hosts a quasar at its core. This quasar, containing a supermassive black hole, emits a powerful radiation cone that affects neighboring galaxies. This interaction can destroy gas and dust clouds, leaving behind only denser regions that may struggle to form stars. Image credit: ESO/M. Kornmesser.

“In the far reaches of the universe, two galaxies are entangled in an exhilarating conflict,” remarked Dr. Paschier Notardem, an astronomer affiliated with the Paris Astronomical Institute.

“On a collision course at speeds of 500 km/s, they collide multiple times, only to push one another away before gearing up for another round.”

“Thus, we refer to this system as the ‘space joust.’ However, these galactic contenders don’t fight fairly, utilizing quasars to strike with beams of radiation.”

Quasars are the luminous cores of certain distant galaxies powered by supermassive black holes, emitting substantial amounts of radiation.

The combination of a quasar with a galaxy was significantly more common during the universe’s first billion years, allowing astronomers to glimpse the remote past using powerful telescopes.

The light from this “joust of the universe” traveled over 11 billion years to reach us, providing a snapshot of the universe when it was merely 18% of its current age.



ALMA image showcasing the molecular gas content of two galaxies involved in a collision. Image credits: ALMA/ESO/NAOJ/NRAO/Balashev et al.

“According to Dr. Sergei Balashev from the Ioffe Institute,

the observations from the new VLT/ALMA indicate that radiation from the quasar J012555.11-012925.00 obliterates the normal gas and dust clouds in the surrounding galaxy, leaving only the densest regions.

These regions are likely too limited for star formation, causing a significant decline in stellar nurseries within the affected galaxy.

However, the transformed galaxies are not the only ones undergoing changes.

“These mergers are believed to funnel substantial amounts of gas into the supermassive black holes at the galaxies’ centers,” Dr. Balashev mentioned.

“In this cosmic arena, fresh supplies of fuel come within reach of black holes that power the quasar.”

“As these black holes are nourished, the quasar can persist in its destructive assault.”

A paper detailing these findings was published today in the journal Nature.

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S. Balashev et al. Quasar radiation transforms gas in a merged companion galaxy. Nature Published online on May 21, 2025. doi:10.1038/s41586-025-08966-4

Source: www.sci.news

The wildflowers and lakes of Death Valley showcase a dramatic contrast in climate

According to climate scientists, the impact of global warming on California’s interior is becoming more evident as desert droughts worsen and rainfall intensifies. Residents of Death Valley are witnessing these changes firsthand. The future of this resilient symbol lies in the ability of the desert’s plants, animals, and local economies to adapt to the evolving conditions in one of the Earth’s harshest environments.

“It’s fascinating to witness these changes up close,” remarked Donnelly. “It’s a clear indication of climate disruption.”

Two Unprecedented Storms

Susan Sorrels, who owns an ecotourism town near Death Valley National Park called Shoshone, described the weather in the area as always erratic. However, recent years have shown a distinct pattern. In early 2022, Death Valley, along with the rest of the American Southwest, experienced a historical drought lasting 22 years, leading to record-low soil moisture levels and the gradual demise of plants such as creosote bushes. The severity of these conditions was a testament to the extreme weather in the region.

“Desert shrubs are incredibly resilient but eventually succumb,” explained Lynn Sweet, a research ecologist at the University of California, Riverside.

In August of the same year, the region was struck by an unprecedented flood, receiving 1.7 inches of rain within a few hours. This storm caused significant damage to park infrastructure and left a lasting impact on the area.

About a year later, the remnants of Hurricane Hillary caused another extraordinary event, dumping 2.2 inches of rain in a day, exceeding the typical annual rainfall. This extreme shift from drought to heavy rainfall exemplifies the unpredictability of the changing climate.

Road workers work along Highway 190, where much of the road was washed away by Tropical Storm Hillary the week before, in Death Valley, Aug. 31, 2023.
Robert Gauthier/Los Angeles Times via Getty Images File

The aftermath of these storms led to challenges for Sorrels and her ecotourism business in Shoshone, with highway closures impacting accessibility during the peak tourist season.

Sorrels mentioned the local struggle to navigate through the economic impact of these weather fluctuations. She highlighted community efforts to expedite road repairs, ultimately reopening the park and highway for visitors.

In a surprising turn of events, Donnelly observed the growth of wildflowers in the region despite adverse conditions. The flowers, thriving in unusual ways, showcased a resilience that defied expectations.

Additionally, the presence of enough water led to the revival of Lake Manly, previously a dry lake bed filled with dust. This resurgence prompted the National Park Service to allow kayaking on the lake, a rare occurrence that highlighted the dramatic changes taking place in the region.

Source: www.nbcnews.com

European Space Agency predicts a dramatic crash landing for satellite on Earth

A European satellite that is malfunctioning is expected to fall to Earth and plunge uncontrollably through the atmosphere on Wednesday.

The European Space Agency said that most of the dead satellite is anticipated to burn up in the atmosphere and any surviving debris is unlikely to cause harm. However, it is challenging to determine the exact time and location of the spacecraft’s fall.

According to the Latest blog posts, the space agency estimated that the re-entry time will be around 10:41 a.m. ET on Wednesday, which would take approximately two hours. Based on the satellite’s orbit, the spacecraft was expected to be somewhere off the coast of North America in the Pacific Ocean during that period.

The space agency explained that much of the uncertainty about the re-entry of satellites is due to the challenge of predicting atmospheric density. Changes in air density, influenced by solar activity, impact the drag experienced by objects passing through Earth’s atmosphere.

The space agency stated that although there is uncertainty about the re-entry point of the dead satellite, it is unlikely to pose a threat to populated areas.

“Most of the satellites will burn out, and the surviving debris will be scattered somewhat randomly over a ground orbit averaging hundreds of kilometers long and tens of kilometers wide (this is why the risks involved are so great). “The reason for this is low),” said an expert from the agency’s Space Debris Countermeasures Office. I wrote it in a blog post.

The spacecraft, known as European Remote Sensing 2 or ERS-2, was an Earth observation satellite that collected data about Earth’s oceans, polar caps, and surface. The space agency said the satellite, launched in April 1995, was also used to monitor severe floods, earthquakes and other natural disasters in remote areas of the world.

Source: www.nbcnews.com

The Factors Behind the Dramatic Behavior of Killer Whales This Year

It’s easy to be misunderstood if your name has the word “murderer” in it.

Still, it appears to have been a wild year for killer whales. From “attacking” and sinking several boats off the coast of southwest Europe to hunting great white sharks around South Africa and Australia, this black-and-white behemoth is living up to its name as of 2023. It looked like.

The whale’s surprising behavior has repeatedly put the spotlight on one of the ocean’s top predators since spring, spawning internet memes and wondering if the whale is just playing around or planning revenge. It’s fueling debate about what’s going on.

But for scientists, the recent orca antics are more fascinating than horrifying, with some saying they show how much there is still to learn about these highly intelligent marine animals.

Perhaps the biggest orca news of the year was a series of mysterious incidents in which killer whales appeared to ram boats off the coast of the Iberian Peninsula. In May, three killer whales collided with the rudder and side of a sailing yacht in the area, causing the yacht to sink.

This “attack” comes amid an observed increase in encounters between killer whales and boats since 2020. Monica Wieland Shields, director of the Orca Behavior Institute, a nonprofit research institute in Washington, said hundreds of incidents have been reported during this time.

At least four ships have sunk in the past two years due to the damage, she said.

No injuries or deaths were reported, and in most cases the whales did not sink boats. However, the incident became so famous that it sparked a meme that heralded the beginning of the “Orca Rebellion” and the “Orca Wars.” Many social media users supported “Team Killer Whales” and claimed that whales had finally fought back against humans.

But Shields said the sinking evoked real fear as well as light-hearted fun.

“So many people have come to my state of Washington this year and asked, ‘Is it safe to see whales here? How big is our boat? Is it possible that a whale will attack this ship?” she said. “I’m worried that instead of people leaving with a sense of respect and fascination with whales, they’re leaving with a fear of whales that’s probably not warranted.”

Among experts, the incident off the coast of the Iberian Peninsula is puzzling and has sparked debate about the whale’s intentions.

Many scientists believe that killer whales do not attack at all.

“They’re not afraid of boats, and there’s nothing to eat there,” said Robert Pittman, a marine ecologist at Oregon State University’s Marine Mammal Research Institute. “They are intelligent, social animals, but they probably live in environments that are less stimulating for their mental abilities.”

So whales sometimes stumble upon something they find interesting and repeat the behavior for a while, he said.

Shields said videos of some of the incidents do not appear to show the killer whale intentionally aiming at the boat’s rudder or hull. Rather, she thought, the animals were likely acting out of curiosity and playfulness.

Josh McInnes, a behavioral ecologist at the University of British Columbia, agreed, noting that killer whales are known to engage in social learning by spreading and picking up behaviors within their pods. That could explain the series of boat encounters, he said.

Mr McInnes compared the behavior to roughhousing.

“Orcas are very athletic. They can grow up to 25 feet long and weigh up to 80,000 pounds, so when they come into physical contact with objects, they can get a little bit forceful,” he said.

Mr Shields said given the whale’s size, it would likely cause much more damage to ships and yachts if it carried out a coordinated attack.

Additionally, the idea that whales are standing up and fighting back doesn’t fit with what scientists know about killer whales.

“Orcas just want to have fun,” Pittman said. “Revenge is not inherently beneficial. Unless you are human, you have no adaptive capacity at all.”

But encounters between killer whales and boats weren’t the only stories making headlines this year. The whale also attracted attention for its ruthless hunting techniques.

In October, the carcass of a great white shark with its liver ripped out washed up on a beach near Portland, Australia. Researchers determined that killer whales were the culprit.

McInnes said killer whales do not normally prey on sharks, but they are capable of preying on sharks and have been previously observed preying on them in waters of Australia, Africa and even the Pacific Northwest. It is said that there is.

And why were sharks missing certain organs? Experts say this was purely practical.

“Sharks generally aren’t very nutritious for killer whales because they’re made of cartilage,” McInnes said. “But the liver is rich in fats and lipids, so it’s a very nutritious part to eat.”

In the past, killer whales have been known to target the liver when preying on sharks. Since 2017, scientists have been tracking the hunts of two killer whales, Port and Starboard, who killed at least eight great white sharks off the coast of South Africa and washed their liverless carcasses ashore.

In a video taken by a whale watching expedition off the coast of San Diego, a killer whale teaches its baby how to hunt by headbutting a dolphin. Erika Sacrison / Gone Whale Watching

However, orca behavior recorded in different parts of the world is generally unrelated. McInnes said different populations of killer whales are genetically distinct and do not normally socialize or interact.

But by studying all the observed events, scientists can gain broader insight into what killer whales are capable of and how they live.

Shields said she had “mixed feelings” about the attention that killer whales will receive in 2023. If anything, she said she hopes the headline will inspire people to get more involved in conservation efforts.

“I really hope that people take away from these stories a certain fascination and appreciation for killer whales,” Shields said. “They are found in every ocean and are present all over the planet. The ocean body closest to where you live is probably home to killer whales. So there’s a lot to learn. there is.”

Source: www.nbcnews.com

The Missoula Glacier Lake’s impact on the dramatic scaly area

Satellite image of parts of Akaland taken on May 14, 2023 by Landsat 8’s Operational Land Imager.

Ejecta from Missoula Glacier Lake has carved out channeled skeletal lands in Washington state.

Southeastern Washington is home to miles of rolling hills and a neat grid of farmland. Dozens of crops It is grown on precious farmland on the Columbia Plateau. But in some places, undulating streaks of scoured soil interrupt a series of angular plots or center-pivot irrigated fields.

These rocky scars channeled scrubland, and they were formed in a series of dramatic floods 10,000 to 20,000 years ago. Landsat 8’s OLI (Operational Land Imager) captured the image of part of Acarland, about 120 kilometers (75 miles) west of Spokane, on May 14, 2023.

The sources of water that carved these unusual landforms remained a mystery to geologists for decades. Then they came to understand that as the Cordilleran Ice Sheet moved south during the last ice age, it formed dams along the Clark Fork River. Glacial Lake Missoula grew behind this ice dam in what is now western Montana and eventually held as much water as Lake Erie and Lake Ontario combined. Geologists estimate that: a dam was formed and broke dozens of times Over thousands of years, each breach releases up to 600 cubic miles of water across the region.

Detailed view of the image above.

Floodwaters flowed south and southwest, eventually emptying into the Columbia River. In the process, they carved grooves, potholes, and long channels known as “coulees” into the volcanic basalt bedrock. The detailed map (above) shows one of these channels and reveals the striking contrast between flood scoured areas and arable land.

The canyon shown here is small compared to the others. Grand Coulee, the largest of the Channeled Scrublands north of this scene. Completed in 1942, Grand Coulee Dam was the largest concrete structure in the world until it was surpassed by dams in South America. Itaipu Dam 1984 and China three gorges dam Established in 2006.Currently America’s largest hydroelectric facility Provides irrigation water to the Columbia Plateau.

NASA Earth Observatory imagery by Lauren Dauphin using Landsat data from the U.S. Geological Survey.

Source: scitechdaily.com