First day of dinosaur extinction, new research


This July 2016 video says about itself:

Experience the Disaster that Wiped Out Dinosaurs

When the dinosaur-killing asteroid struck Earth, most of the impact energy was directed outwards and upwards into space. Only 1% of the force traveled down into the ground, but it was enough to ring the planet like a bell and wipeout species around the globe. Only those creatures able to seek shelter from the intense heat on the surface survived.

From the University of Texas at Austin in the USA:

Rocks at asteroid impact site record first day of dinosaur extinction

September 9, 2019

Summary: The research centers on the asteroid impact that wiped out non-avian dinosaurs, with the researchers getting the most detailed look yet of the aftermath that followed by examining the rocks and debris that filled the crater within the first 24 hours after impact.

When the asteroid that wiped out the dinosaurs slammed into the planet, the impact set wildfires, triggered tsunamis and blasted so much sulfur into the atmosphere that it blocked the sun, which caused the global cooling that ultimately doomed the dinos.

That’s the scenario scientists have hypothesized. Now, a new study led by The University of Texas at Austin has confirmed it by finding hard evidence in the hundreds of feet of rocks that filled the impact crater within the first 24 hours after impact.

The evidence includes bits of charcoal, jumbles of rock brought in by the tsunami‘s backflow and conspicuously absent sulfur. They are all part of a rock record that offers the most detailed look yet into the aftermath of the catastrophe that ended the Age of Dinosaurs, said Sean Gulick, a research professor at the University of Texas Institute for Geophysics (UTIG) at the Jackson School of Geosciences.

“It’s an expanded record of events that we were able to recover from within ground zero,” said Gulick, who led the study and co-led the 2016 International Ocean Discovery Program scientific drilling mission that retrieved the rocks from the impact site offshore of the Yucatan Peninsula. “It tells us about impact processes from an eyewitness location.”

The research was published in the Proceedings of the National Academy of Sciences on Sept. 9 and builds on earlier work co-led and led by the Jackson School that described how the crater formed and how life quickly recovered at the impact site. An international team of more than two dozen scientists contributed to this study.

Most of the material that filled the crater within hours of impact was produced at the impact site or was swept in by seawater pouring back into the crater from the surrounding Gulf of Mexico. Just one day deposited about 425 feet of material — a rate that’s among the highest ever encountered in the geologic record. This breakneck rate of accumulation means that the rocks record what was happening in the environment within and around the crater in the minutes and hours after impact and give clues about the longer-lasting effects of the impact that wiped out 75% of life on the planet.

Gulick described it as a short-lived inferno at the regional level, followed by a long period of global cooling.

“We fried them and then we froze them,” Gulick said. “Not all the dinosaurs died that day, but many dinosaurs did.”

Researchers estimate the asteroid hit with the equivalent power of 10 billion atomic bombs of the size used in World War II. The blast ignited trees and plants that were thousands of miles away and triggered a massive tsunami that reached as far inland as Illinois. Inside the crater, researchers found charcoal and a chemical biomarker associated with soil fungi within or just above layers of sand that shows signs of being deposited by resurging waters. This suggests that the charred landscape was pulled into the crater with the receding waters of the tsunami.

Jay Melosh, a Purdue University professor and expert on impact cratering, said that finding evidence for wildfire helps scientists know that their understanding of the asteroid impact is on the right track.

“It was a momentous day in the history of life, and this is a very clear documentation of what happened at ground zero,” said Melosh, who was not involved with this study.

However, one of the most important takeaways from the research is what was missing from the core samples. The area surrounding the impact crater is full of sulfur-rich rocks. But there was no sulfur in the core.

That finding supports a theory that the asteroid impact vaporized the sulfur-bearing minerals present at the impact site and released it into the atmosphere, where it wreaked havoc on the Earth’s climate, reflecting sunlight away from the planet and causing global cooling. Researchers estimate that at least 325 billion metric tons would have been released by the impact. To put that in perspective, that’s about four orders of magnitude greater than the sulfur that was spewed during the 1883 eruption of Krakatoa — which cooled the Earth’s climate by an average of 2.2 degrees Fahrenheit for five years.

Although the asteroid impact created mass destruction at the regional level, it was this global climate change that caused a mass extinction, killing off the dinosaurs along with most other life on the planet at the time.

“The real killer has got to be atmospheric”, Gulick said. “The only way you get a global mass extinction like this is an atmospheric effect.”

The research was funded by a number of international and national support organizations, including the National Science Foundation.

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Gigantoraptor dinosaurs, video


This 8 September 2019 video says about itself:

The Giant ‘Egg Thief‘ – Gigantoraptor

Oviraptorosaurs are an amazing group of dinosaurs, and there’s one species, which grew to giant sizes, that has some particularly fascinating mysteries surrounding it.

New duck-billed dinosaur discovery in Japan


This 6 August 2019 video says about itself:

New duck-billed dinosaur, Kamuysaurus japonicus, discovered by scientists

A dinosaur that was unearthed from 72-million-year-old marine deposits in northern Japan belongs to a new genus and species, researchers announced. A partial tail was first found in 2013 in Mukawa Town, Hokkaido, in Japan. Later excavations discovered a nearly complete skeleton that is the largest ever found in Japan.

From Hokkaido University in Japan:

A new duck-billed dinosaur

September 5, 2019

The dinosaur, whose nearly complete skeleton was unearthed from 72 million year old marine deposits in Mukawa Town in northern Japan, belongs to a new genus and species of a herbivorous hadrosaurid dinosaur, according to the study published in Scientific Reports. The scientists named the dinosaur Kamuysaurus japonicus.

A partial tail of the dinosaur was first discovered in the outer shelf deposits of the Upper Cretaceous Hakobuchi Formation in the Hobetsu district of Mukawa Town, Hokkaido, in 2013. Ensuing excavations found a nearly complete skeleton that is the largest dinosaur skeleton ever found in Japan. It’s been known as “Mukawaryu”, nicknamed after the excavation site.

In the current study, a group of researchers led by Professor Yoshitsugu Kobayashi of the Hokkaido University Museum conducted comparative and phylogenetic analyses on 350 bones and 70 taxa of hadrosaurids, which led to the discovery that the dinosaur belongs to the Edmontosaurini clade, and is closely related to Kerberosaurus unearthed in Russia and Laiyangosaurus found in China.

The research team also found that Kamuysaurus japonicus, or the deity of Japanese dinosaurs, has three unique characteristics that are not shared by other dinosaurs in the Edmontosaurini clade: the low position of the cranial bone notch, the short ascending process of the jaw bone, and the anterior inclination of the neural spines of the sixth to twelfth dorsal vertebrae.

According to the team’s histological study, the dinosaur was an adult aged 9 or older, measured 8 meters long and weighed 4 tons or 5.3 tons (depending on whether it was walking on two or four legs respectively) when it was alive. The frontal bone, a part of its skull, has a big articular facet connecting to the nasal bone, suggesting the dinosaur may have had a crest. The crest, if it existed, is believed to resemble the thin, flat crest of Brachylophosaurus subadults, whose fossils have been unearthed in North America.

The study also shed light on the origin of the Edmontosaurini clade and how it might have migrated. Its latest common ancestors spread widely across Asia and North America, which were connected by what is now Alaska, allowing them to travel between the two continents. Among them, the clade of Kamuysaurus, Kerberosaurus and Laiyangosaurus inhabited the Far East during the Campanian, the fifth of six ages of the Late Cretaceous epoch, before evolving independently.

The research team’s analyses pointed to the possibility that ancestors of hadrosaurids and its subfamilies, Hadrosaurinae and Lambeosaurinae, preferred to inhabit areas near the ocean, suggesting the coastline environment was an important factor in the diversification of the hadrosaurids in its early evolution, especially in North America.

Turtle trampled by dinosaur, other discoveries


This 4 September 2019 video says about itself:

A New Species of Whale & A Turtle Trodden on by a Dinosaur– 7 Days of Science

That poor turtle! That wasn’t funny at all! What are you talking about?! Oh, before I forget, here’s a link to One World.

That turtle was Plesiochelys bigleri, from the Jurassic age in Switzerland, trampled by a sauropod dinosaur. See here.

Apparently, sauropod dinosaurs were not as good in sparing turtles’ and tortoises’ lives as these modern African elephants.

Tyrannosarus rex, air conditioner in its head


This 2018 video is called 10 Interesting Facts About TYRANNOSAURUS REX.

This August 2019 video says about itself:

What do the T-rex, crocodiles and alligators have in common? Casey Holliday, a professor of anatomy at MU, used thermal imaging to find that these three creatures used an internal cooling system to stay cool in the heat.

From the University of Missouri-Columbia in the USA:

T. Rex had an air conditioner in its head, study suggests

September 4, 2019

Tyrannosaurus rex, one of the largest meat-eating dinosaurs on the planet, had an air conditioner in its head, suggest scientists from the University of Missouri, Ohio University and University of Florida, while challenging over a century of previous beliefs.

In the past, scientists believed two large holes in the roof of a T. rex’s skull — called the dorsotemporal fenestra — were filled with muscles that assist with jaw movements.

But that assertion puzzled Casey Holliday, a professor of anatomy in the MU School of Medicine and lead researcher on the study.

“It’s really weird for a muscle to come up from the jaw, make a 90-degree turn, and go along the roof of the skull,” Holliday said. “Yet, we now have a lot of compelling evidence for blood vessels in this area, based on our work with alligators and other reptiles.”

Using thermal imaging — devices that translate heat into visible light — researchers examined alligators at the St. Augustine Alligator Farm Zoological Park in Florida. They believe their evidence offers a new theory and insight into the anatomy of a T. rex’s head.

“An alligator’s body heat depends on its environment,” said Kent Vliet, coordinator of laboratories at the University of Florida’s Department of Biology. “Therefore, we noticed when it was cooler and the alligators are trying to warm up, our thermal imaging showed big hot spots in these holes in the roof of their skull, indicating a rise in temperature. Yet, later in the day when it’s warmer, the holes appear dark, like they were turned off to keep cool. This is consistent with prior evidence that alligators have a cross-current circulatory system — or an internal thermostat, so to speak.”

Holliday and his team took their thermal imaging data and examined fossilized remains of dinosaurs and crocodiles to see how this hole in the skull changed over time.

“We know that, similarly to the T. rex, alligators have holes on the roof of their skulls, and they are filled with blood vessels,” said Larry Witmer, professor of anatomy at Ohio University’s Heritage College of Osteopathic Medicine. “Yet, for over 100 years we’ve been putting muscles into a similar space with dinosaurs. By using some anatomy and physiology of current animals, we can show that we can overturn those early hypotheses about the anatomy of this part of the T. rex’s skull.”

Deinonychus caused new views on dinosaurs


This 28 August 2019 video says about itself:

The Raptor That Made Us Rethink Dinosaurs

In 1964, a paleontologist named John Ostrom unearthed some fascinating [Deinonychus] fossils from the mudstone of Montana. Its discovery set the stage for what’s known today as the Dinosaur Renaissance, a total re-thinking of what we thought we knew about dinosaurs.

Australian dinosaurs, videos


This 30 June 2019 video says about itself:

Australian Dinosaurs (Part 1)

Here we take a look at a few of the most unique and interesting dinosaurs that were first discovered in Australia.

This 14 July 2019 video says about itself:

Australian Dinosaurs (Part 2)

Here we’re taking a look at 3 more species of dinosaurs that were all first discovered in Australia.