Natural History (13.8 billion years BC – 3.3 million BC)

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weatheriscool
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Re: Natural History (13.8 billion years BC – 3.3 million BC)

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wjfox wrote: Tue Oct 04, 2022 6:50 pm Asteroid that wiped out the dinosaurs also triggered a global tsunami

Published 1:59 PM EDT, Tue October 4, 2022

When a city-size asteroid slammed into Earth 66 million years ago, it wiped out the dinosaurs – and sent a monster tsunami rippling around the planet, according to new research.

[...]

It’s the first global simulation of the tsunami caused by the Chicxulub impact to be published in a peer-reviewed scientific journal, according to the authors.

The tsunami was powerful enough to create towering waves more than a mile high and scour the ocean floor thousands of miles away from where the asteroid hit, according to the study. It effectively wiped away the sediment record of what happened before the event, as well as during it.

“This tsunami was strong enough to disturb and erode sediments in ocean basins halfway around the globe, leaving either a gap in the sedimentary records or a jumble of older sediments,” said lead author Molly Range, who began working on the study as an undergraduate student and completed it for her master’s thesis at the University of Michigan.

Researchers estimate that the tsunami was up to 30,000 times more energetic than the December 26, 2004 Indian Ocean tsunami, one of the largest on record, that killed more than 230,000 people. The energy of the asteroid impact was at least 100,000 times larger than the Tonga volcanic eruption earlier this year.

Read more: https://edition.cnn.com/2022/10/04/worl ... index.html


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I'd bet the wave would look kind of like the one in 2012. ;) It was probably still 500+ even entering the indian ocean. Imagine such a tsunami happening now. 5 billion people dead?
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Re: Natural History (13.8 billion years BC – 3.3 million BC)

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weatheriscool wrote: Wed Oct 05, 2022 5:43 am
Imagine such a tsunami happening now. 5 billion people dead?
Difficult to calculate, but around 40% of the world's population lives within 100 km of the coast.

I think casualties from the immediate impact wouldn't actually be that high (relatively speaking). Most deaths would probably come later, from the plunging temperatures and collapse of agriculture.

It seems unlikely that the human race could survive an impact on the scale of Chicxulub. It would be a thoroughly miserable end. Only a few mammals smaller than, say, a cat, would survive – in underground burrows, etc.
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Re: Natural History (13.8 billion years BC – 3.3 million BC)

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The Big Bang theory explains where all the hydrogen and helium in the universe came from.
In the 1940s, Ralph Alpher and George Gamow calculated that the early universe was hot and dense enough to make virtually all the helium, lithium and deuterium (hydrogen with a neutron attached) present in the cosmos today; later research showed where the primordial hydrogen came from. This is known as “Big Bang nucleosynthesis,” and it stands as one of the most successful predictions of the theory. The heavier elements (such as oxygen, iron and uranium) were formed in stars and supernova explosions.

The best evidence for the Big Bang is in the form of microwaves. Early on, the whole universe was dense enough to be completely opaque. But at a time roughly 380,000 years after the Big Bang, expansion spread everything out enough to make the universe transparent.

The light released from this transition, known as the cosmic microwave background (CMB), still exists. It was first observed in the 1960s by Arno Penzias and Robert Wilson. That discovery cemented the Big Bang theory as the best description of the universe; since then, observatories such WMAP and Planck have used the CMB to tell us a lot about the total structure and content of the cosmos.
By the way, I have an astrology blog, it is mainly about zodiac signs compatibility and personality.
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Re: Natural History (13.8 billion years BC – 3.3 million BC)

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Impact that killed the dinosaurs may have triggered a 'mega-earthquake' that lasted weeks to months
https://phys.org/news/2022-10-impact-di ... weeks.html
by Geological Society of America
Some 66 million years ago, a 10-kilometer asteroid hit Earth, triggering the extinction of the dinosaurs. New evidence suggests that the Chicxulub impact also triggered an earthquake so massive that it shook the planet for weeks to months after the collision. The amount of energy released in this "mega-earthquake" is estimated at 1023 joules, which is about 50,000 times more energy than was released in the magnitude 9.1 Sumatra earthquake in 2004.

Hermann Bermúdez will present evidence of this "mega-earthquake" at the upcoming GSA Connects meeting in Denver this Sunday, October 9. Earlier this year, Bermúdez visited outcrops of the infamous Cretaceous-Paleogene (K-Pg) mass extinction event boundary in Texas, Alabama, and Mississippi to collect data, supplementing his previous work in Colombia and Mexico documenting evidence of the catastrophic impact.
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Re: Natural History (13.8 billion years BC – 3.3 million BC)

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Research Finds Unprecedented Levels of Insects Damaging Plants
October 10, 2022

Introduction:
(EurekAlert) Insects today are causing unprecedented levels of damage to plants, even as insect numbers decline, according to new research led by University of Wyoming scientists.

The first-of-its-kind study compares insect herbivore damage of modern-era plants with that of fossilized leaves from as far back as the Late Cretaceous period, nearly 67 million years ago. The findings appear in the prestigious journal Proceedings of the National Academy of Sciences.

“Our work bridges the gap between those who use fossils to study plant-insect interactions over deep time and those who study such interactions in a modern context with fresh leaf material,” says the lead researcher, UW Ph.D. graduate Lauren Azevedo-Schmidt, now a postdoctoral research associate at the University of Maine. “The difference in insect damage between the modern era and the fossilized record is striking.”

Azevedo-Schmidt conducted the research along with UW Department of Botany and Department of Geology and Geophysics Professor Ellen Currano, and Assistant Professor Emily Meineke of the University of California-Davis.

The study examined fossilized leaves with insect feeding damage from the Late Cretaceous through the Pleistocene era, a little over 2 million years ago, and compared them with leaves collected by Azevedo-Schmidt from three modern forests. The detailed research looked at different types of damage caused by insects, finding marked increases in all recent damage compared to the fossil record.
Read more here: https://www.eurekalert.org/news-releases/967297

caltrek’s comment: The article goes on to explain how human activities may account for the differences. The way things are going, this means the results of such studies will be restricted to a postgraduate audience.

Why?

Because presenting these results to younger people might make them “feel bad” about themselves. Better to condemn the future of our biosphere to continued degradation than present anything that might make children “feel bad” about themselves. Of course, in such circumstances, one suspects that it is the tender feelings of parents which is really at center stage.
Don't mourn, organize.

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Re: Natural History (13.8 billion years BC – 3.3 million BC)

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Ostrich-like dinosaurs found in Mississippi are among the world's largest ornithomimosaurs at more than 800 kg
https://phys.org/news/2022-10-ostrich-l ... rgest.html
by Public Library of Science
Ostrich-like dinosaurs called ornithomimosaurs grew to enormous sizes in ancient eastern North America, according to a study published October 19, 2022, in the open-access journal PLOS ONE by Chinzorig Tsogtbaatar of the North Carolina Museum of Natural Sciences and colleagues.
During the Late Cretaceous Period, North America was split by a seaway into two landmasses: Laramidia to the west and Appalachia to the east. But fossils from Appalachia are rare, and therefore ancient ecosystems from this region are poorly understood. In this study, Chinzorig and colleagues describe new fossils of ornithomimosaur dinosaurs from the Late Cretaceous Eutaw Formation of Mississippi.

Ornithomimosaurs, the so-called "bird-mimic" dinosaurs, were superficially ostrich-shaped with small heads, long arms, and strong legs. The new fossils, including foot bones, are around 85 million years old, making them a rare glimpse into a poorly known interval of North American dinosaur evolution

By comparing the proportions of these fossils and the patterns of growth within the bones, the authors determined that the fossils likely represent two different species of ornithomimosaurs, one relatively small and one very large. They estimate the larger species to have weighed over 800 kg, and the individual examined was likely still growing when it died. This makes it among the largest ornithomimosaurs known.
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Re: Natural History (13.8 billion years BC – 3.3 million BC)

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How Magnetism Could Help Explain Earth’s Formation
November 2, 2022

Introduction:
(EurekAlert) There are several theories about how the Earth and the Moon were formed, most involving a giant impact. They vary from a model where the impacting object strikes the newly formed Earth a glancing blow and then escapes, through to one where the collision is so energetic that both the impactor and the Earth are vaporized.

Now scientists at the University of Leeds and the University of Chicago have analysed the dynamics of fluids and electrically conducting fluids and concluded that the Earth must have been magnetized either before the impact or as a result of it.

They claim this could help to narrow down the theories of the Earth-Moon formation and inform future research into what really happened.

Professor David Hughes, an applied mathematician in the School of Mathematics at the University of Leeds, said: “Our new idea is to point out that our theoretical understanding of the Earth’s magnetic field today can actually tell us something about the very formation of the Earth-Moon system.

“At first glance, this seems somewhat surprising, and previous theories had not recognized this potentially important connection.”
Read more here: https://www.eurekalert.org/news-releases/969845

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Image courtesy of NASA/JPL
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Re: Natural History (13.8 billion years BC – 3.3 million BC)

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New pterosaur species identified in sub-Saharan Africa
https://phys.org/news/2022-11-pterosaur ... frica.html
by Southern Methodist University
With wings spanning nearly 16 feet, a new species of pterosaurs has been identified from the Atlantic coast of Angola.

An international team, including two vertebrate paleontologists from Southern Methodist University (SMU), named the new genus and species Epapatelo otyikokolo. This flying reptile of the dinosaur age was found in the same region of Angola as fossils from large marine animals currently on display at the Smithsonian's National Museum of Natural History.

Pterosaur fossils that date back to the Late Cretaceous are extremely rare in sub-Saharan Africa, said team member Michael J. Polcyn, research associate in the Huffington Department of Earth Sciences and senior research fellow, ISEM at SMU (Southern Methodist University).

"This new discovery gives us a much better understanding of the ecological role of the creatures that were flying above the waves of Bentiaba, on the west coast of Africa, approximately 71.5 million years ago," Polcyn said.

Paleontologist Louis L. Jacobs, SMU professor emeritus of earth sciences and president of ISEM, an interdisciplinary institute at the university, also collaborated on the research. The team's findings were published in the journal Diversity.
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Re: Natural History (13.8 billion years BC – 3.3 million BC)

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Hundred-year-old Riddle in Botany Reveals Key Plant Adaptation to Dry Land
November 10, 2022

Introduction:
(EurekAlert) Průhonice, Czech Republic - The green world that we live in would not have been possible without hidden changes to the plant body over the last 400 million years. To grow beyond just centimetres tall outside of the wettest places on land, plants had to re-arrange their water-conducting tissues to keep them safe from drought. A new study by Martin Bouda of the Institute of Botany of the Czech Academy of Science and co-authors, published in the journal Science, shows how the solution to a hundred-year-old debate in botany reveals a key adaptation that allowed plants to colonise dry land.

Background: All but the tiniest plants need vascular tissues to supply water throughout their body and avoid drying out as they capture carbon from the surrounding air. If a plant is subjected to drought, the chain of water molecules being pulled up the stem can break, forming an embolism: a bubble of gas that blocks water transport in one entire vascular conduit. If embolism spreads from this conduit throughout the tissue, the plant’s water-supplying vasculature becomes effectively blocked, the plant dries out and dies.

The new discovery shows that the original arrangement of vascular tissues—a cylinder at the centre of the stem—becomes increasingly vulnerable to embolism spread with size. "If conduits are all bundled up together the plant may face exponential spread of embolism on the resulting vascular network. If they are strung out in a long narrow shape, embolism has to overcome many successive cell walls to go very far, which can save the plant’s life in a drought,” says Dr. Bouda, the lead author of the study.

The first vascular plants were just centimetres tall and constrained to live where water was readily available. To grow taller and begin exploring the landscape, they first had to find alternatives to their ancestral vascular arrangement. “We were struck by the fact that only very few living plants have kept the original layout of the stem, which puts the vascular tissue in a cylinder right at the centre. That seeming detail actually held the key to deciphering this whole evolutionary episode,” adds Bouda.
Read more here: https://www.eurekalert.org/news-releases/970412
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Re: Natural History (13.8 billion years BC – 3.3 million BC)

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New species of Triassic-era crocodile-like reptile unearthed in Brazil
https://phys.org/news/2022-11-species-t ... rthed.html
by Bob Yirka , Phys.org
A pair of researchers from the Federal University of Santa Maria working with a colleague from the Federal University of Juiz de Fora, have identified a new species of Triassic-era reptile that was unearthed recently at a dig site in Brazil.

In their paper published in Journal of Systematic Palaeontology, Rodrigo Temp Müller, Mauricio Silva Garcia and André de Oliveira Fonseca, describe the fossil they found and where the new species fits in the historical record.

Paleontologists have been working for some time at the Rio Grande do Sul dig site in Brazil, and in so doing have found a large number of dinosaur bones. During that time, few reptile remains have been found, however.

Thus, the researchers were surprised when they found a complete leg fossil from an unknown ancient reptile, along with configurations of the foot that was once attached to it. The researchers knew the fossils were ancient; the rock around them has been dated to 230 million years ago—during a time when the dinosaurs were still roaming the earth.

Subsequent analysis of the fossil showed that it belonged to an ancient class of reptiles called proterochampsids—a group that had only ever been found in Argentina and Brazil. Prior research has shown that despite having physical characteristics similar to modern crocodiles and alligators, no strong degree of kinship has been found.

The researchers also found that the fossil represented a species that had not been seen before, which meant that they got to name it. They chose Tenoscelida aurantiacus, a nod to the slenderness of the leg and the orange color of the rocky bed in which it was found.

Based on the size of the fossil, the researchers estimated the creature would have been approximately 1.40 meters long, and would have walked on all-fours. They also suspect, based on similar species of the time, that the reptile was a meat eater. They opine that its build lent itself to a life near the water, similar to modern alligators.
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