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

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Research Indicates Comet Impacts Formed Continents When the Solar System Entered Galactic Arms
August 24, 2022

Introduction:

(EruekAlert) New Curtin research has found evidence that Earth’s early continents resulted from being hit by comets as our Solar System passed into and out of the spiral arms of the Milky Way Galaxy, turning traditional thinking about our planet’s formation on its head.

The new research, published in Geology, challenges the existing theory that Earth’s crust was solely formed by processes inside our planet, casting a new light on the formative history of Earth and our place in the cosmos.

Lead researcher Professor Chris Kirkland, from the Timescales of Mineral Systems Group within Curtin’s School of Earth and Planetary Sciences, said studying minerals in the Earth’s crust revealed a rhythm of crust production every 200 million years or so that matched our Solar System’s transit through areas of the galaxy with a higher density of stars.
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“From looking at the age and isotopic signature of minerals from both the Pilbara Craton in Western Australia and North Atlantic Craton in Greenland, we see a similar rhythm of crust production, which coincides with periods during which the Solar System journeyed through areas of the galaxy most heavily populated by stars.”

“When passing through regions of higher star density, comets would have been dislodged from the most distant reaches of the Solar System, some of which impacted Earth.

Read more here: https://www.eurekalert.org/news-releases/962656

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Trove of Jurassic-Era Fossilized Fish Discovered on an English Dairy Farm
by Madeleine Muzdakis
August 28, 2022

Introduction:

(My Modern Met) One might expect to find a lot of cows, manure, and hay on a dairy farm. However, British fossil hunters Neville and Sally Hollingworth discovered something less expected: a 183-million-year-old fossilized fish. Not just any fossil, the pair had discovered a specimen preserved as if leaping, toothy mouth agape, towards the viewer. Researchers investigating this 3D find have since uncovered a previously unknown Jurassic fossil bed, one of the most exceptional sites discovered in years.

The Hollingworths are known for finding fossils, including mammoth skeletons. “It was a real surprise because, when you find fossils, most of the time they've been pressed flat through pressure over time,” Neville said. “But when we prepared this one, to reveal its bones bit by bit, it was amazing because we suddenly realized its skull was uncrushed.” The ferocious fossil had emerged from a chunk of limestone which was eroding on a dairy farm in the village of Kings Stanley, Gloucestershire, England.

The surprised farmer gave the pair and a team of researchers from the University of Manchester permission to dig on his property. The crew carefully excavated more limestone nodules, cracking them open to expose more marine fossils. Fish, squid, and the bones of two ichthyosaurs appeared. The latter were large, dolphin-like reptiles that roamed ancient seas. Some of the fish even have preserved soft tissue such as skin, giving the fossils a surprisingly lifelike appearance. Fossilized wood and insects suggest the ancient waters were not far from land.

“We've got the whole food chain,” paleontologist Dr. Dean Lomax, said. “So this Pachycormus would have been eating the smaller fish and squids. And then, the ichthyosaurs would have been eating the Pachycormus.” Continuing, “These sites tell you there are still many nationally and indeed internationally significant fossil discoveries yet to be made in the UK.”

The Hollingworths compared the find to other historic discoveries.”The last comparable exposure like this was the so-called Strawberry Bank Lagerstätte, in Somerset, in the 1800s—that got built over,” Sally said. “The Court Farm site allows scientists to do modern research with fresh, in-situ material.” Excavated fossils will be exhibited locally for all to see.

See photos here: https://mymodernmet.com/jurassic-fossilized-fish/

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Scientists Indicate that Land Plants Changed Earth’s River System
August 30, 2022

Extract::

(EurekAlert) Scientists at the University of Southampton have discovered that the evolution of land plants caused a sudden shift in the composition of Earth’s continents.
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The evolution of land plants took place about 430 million years ago during the Silurian Period, when North America and Europe were conjoined in a landmass called Pangaea.

The proliferation of plants completely transformed Earth’s biosphere – those parts of the planet’s surface where life thrives – paving the way for the advent of dinosaurs about 200 million years later.

“Plants caused fundamental changes to river systems, bringing about more meandering rivers and muddy floodplains, as well as thicker soils,” says Dr Christopher Spencer, Assistant Professor at Queen’s University in Kingston, Ontario, lead author of the study. “This shift was tied to the development of plant rooting systems that helped produce colossal amounts of mud (by breaking down rocks) and stabilised river channels, which locked up this mud for long periods.”

Read more here: https://www.eurekalert.org/news-releases/963296

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Discovery and Naming of Africa’s Oldest Known Dinosaur
August 31, 2022

Introduction:

(EurekAlert) An international team of paleontologists led by Virginia Tech has discovered and named a new, early dinosaur. The skeleton — incredibly, mostly intact — was first found by a graduate student in the Virginia Tech Department of Geosciences and other paleontologists over the course of two digs, in 2017 and 2019.

The findings of this new sauropodomorph — a long-necked dinosaur — newly named Mbiresaurus raathi were been published today in the journal Nature. The skeleton is, thus far, the oldest dinosaur skeleton ever found in Africa. The animal is estimated to have been 6 feet long with a long tail. It weighed anywhere from 20 to 65 pounds. The skeleton, missing only some of the hand and portions of the skull, was found in northern Zimbabwe.

“The discovery of Mbiresaurus raathi fills in a critical geographic gap in the fossil record of the oldest dinosaurs and shows the power of hypothesis-driven fieldwork for testing predictions about the ancient past,” said Christopher Griffin, who graduated in 2020 with a Ph.D. in geosciences from the Virginia Tech College of Science.

Griffin added, “These are Africa’s oldest-known definitive dinosaurs, roughly equivalent in age to the oldest dinosaurs found anywhere in the world. The oldest known dinosaurs — from roughly 230 million years ago, the Carnian Stage of the Late Triassic period — are extremely rare and have been recovered from only a few places worldwide, mainly northern Argentina, southern Brazil, and India.”

Sterling Nesbitt, associate professor of geosciences, also is an author on the study. “Early dinosaurs like Mbiresaurus raathi show that the early evolution of dinosaurs is still being written with each new find and the rise of dinosaurs was far more complicated than previously predicted,” he said.

Read more here: https://www.eurekalert.org/news-releases/963320

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A new discovery shows major flowering plants are 150 million years older than previously thought
https://phys.org/news/2022-08-discovery ... older.html
by Byron Lamont, The Conversation

A major group of flowering plants that are still around today, emerged 150 million years earlier than previously thought, according to a new study published today in Trends in Plant Science. This means flowering plants were around some 50 million years before the dinosaurs.

The plants in question are known as the buckthorn family or Rhamnaceae, a group of trees, shrubs and vines found worldwide. The finding comes from subjecting data on 100-million-year old flowers to powerful molecular clock techniques—as a result, we now know Rhamnaceae arose more than 250 million years ago.

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We May Know What Killed Off Australia’s Giant Extinct “Demon Ducks Of Doom”
by Stephen Luntz
September 2, 2022

Introduction:

(IFL Science) Bones of the extinct Dromornis stirtoni, probably the largest bird that ever lived, have revealed the fatal weakness that destroyed their descendants 7 million years later – they took too long to breed.

Before they died out around 50,00 years ago, Australia once hosted birds as much as four times bigger than ostriches, the largest modern avians. Among these, possibly the largest was Dromornis stirtoni. Dromornis were mihirungs, relatives of chickens and ducks that grew to 3 meters (10 feet) tall and weighed 500 kilograms (1,100 pounds), which is why they have been nicknamed “demon ducks of doom”.

A study in the Anatomical Record compares the growth patterns recorded in the bones of D. stirtoni and Genyornis newtoni, the last of the mihirungs to go extinct. Although D. stirtoni grew immensely fast for the first two years, they then slowed down and didn’t achieve breeding size until much later. Genyornis reached its full size earlier, but still inherited the late breeding of its giant ancestor, leaving it with no capacity to deal with the arrival of a new hunter, humans.

Around 8 million years ago Australia had a very different climate, with rainforests in the continent’s heart, Dr Trevor Worthy of Flinders University told IFLScience. These forests supported three species of mihirungs, including the largest, D. stirtoni.

Read more here: https://www.iflscience.com/we-may-know ... oom-65173

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Earliest known mammal identified using fossil tooth records

September 06 2022 02:32 PM



The earliest known extinct mammal has been identified using fossil tooth records.

Brasilodon quadrangularis was a small ‘shrew-like’ animal that measured around 20cm in length and had two sets of teeth.

The tiny animal existed at the same time as some of the oldest dinosaurs and sheds light on the evolution of modern mammals, experts say.

Its fossil records date back 225 million years, predating Morganucodon – the previously confirmed first mammal – by approximately 20 million years.

Mammalian glands, which produce milk and feed the young of mammals today, have not been preserved in any fossils found to date.

https://www.belfasttelegraph.co.uk/news ... 65926.html

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You Don't Actually Have A 'Lizard Brain', Evolutionary Study Reveals
Michele Starr
September 7, 2022

Introduction:

(Science Alert) A new study has shown that the concept of the mammalian 'lizard brain' can be well and truly put to bed.

Based on a study that examined brains of bearded dragons (Pogona vitticeps), large lizards from the Australian desert, scientists have shown that mammal and reptile brains evolved separately from a common ancestor. It's another nail in the coffin of the notion of the so-called triune brain.

The idea of the lizard brain first emerged and rose to popularity in the 1960s and 1970s, based on comparative anatomical studies. Parts of the mammalian brain, neuroscientist Paul MacLean noticed, were very similar to parts of the reptilian brain. This led him to the conclusion that the brain had evolved in stages, after life moved to land.

Further extracts:

However, neuroscientists have been decrying the model for decades. The brain just doesn't work like that, in discrete sections that each play a separate part. Brain regions, anatomically distinct as they are, are highly interconnected, a web of humming neural networks. And with the advent of new techniques, we can start to better understand how brains evolved.

In a new study, a team of researchers from the Max Planck Institute for Brain Research turned to actual lizard brains to investigate, publishing their findings in a paper led by neuroscience graduate students David Hain and Tatiana Gallego-Flores.

Read more of the Science Alert article here: https://www.sciencealert.com/you-dont- ... y-reveals

Read an abstract of the study conducted by the Max Planck Institute for Brain Research here:
https://www.science.org/doi/10.1126/science.abp8202

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In Ethiopia, scientists identify a fossil otter the size of a lion
https://phys.org/news/2022-09-ethiopia- ... -size.html
by Earth Institute at Columbia University

Scientists have identified a new species of long-extinct otter in Ethiopia that was the size of a modern lion. Weighing an estimated 200 kilograms, or 440 pounds, it is the largest otter ever described; it would have rubbed elbows, and possibly competed for food, with our much smaller ancestors when it lived alongside them 3.5 million to 2.5 million years ago. A paper describing the animal just appeared in the French scientific journal Comptes Rendus Palevol.

"The peculiar thing, in addition to its massive size, is that [isotopes] in its teeth suggest it was not aquatic, like all modern otters," said study coauthor Kevin Uno, a geochemist at the Columbia Climate School's Lamont-Doherty Earth Observatory. "We found it had a diet of terrestrial animals, also differing from modern otters."

Current otters weigh 4 to13 pounds for the Asian small-clawed otter, up to about 70 pounds for the South American giant otter and 100 pounds for the North Pacific sea otter. Several giant otters are known to have populated Eurasia and Africa from about 6 million to 2 million years ago. Among these, the extinct genus Enhydriodon is the best known because its remains, although fragmentary, have been found in many locales, particularly in eastern Africa. The newly described species has been named Enhydriodon omoensis, after southwestern Ethiopia's Lower Omo Valley, where it was uncovered.

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Earliest land animals had fewer skull bones than fish – restricting their evolution, scientists find

9 Sep 2022

The skulls of tetrapods had fewer bones than extinct and living fish, limiting their evolution for millions of years, according to a latest study.

By analysing fossil skulls of animals across the transition from an aquatic to terrestrial environment, researchers from the University of Bristol, Barcelona’s Universitat Pompeu Fabra and University College London discovered that tetrapods had more complex connections between their skull bones than fish. And, rather than promoting the diversification of life on land, these changes to skull anatomy actually restricted the evolution of tetrapod skulls.

Tetrapods evolved from fish and were the earliest land animals with limbs and digits; the ancestors of everything from amphibians to humans.

The research, published this week in Science Advances, quantified the organisation of skull bones in over 100 living and fossil animals to better understand how skulls changed as tetrapods evolved.

Lead author James Rawson of Bristol’s School of Earth Sciences said: “Tetrapod skulls generally have fewer skull bones than their fish ancestors, but simply counting the number of bones misses some important data. We used a technique called network analysis, where the arrangement of skull bones - which bones connect to which - is recorded in addition to bone number.”

Author Dr Borja Esteve-Altava, an expert in this technique, said: “Traditionally, anatomy research has been mostly descriptive or qualitative. Network analysis provides a sound mathematical framework to quantify anatomical relations among bones: a kind of data often overlooked in most studies on morphological evolution.”

The authors found that tetrapods having fewer skull bones than fish made the organisation of their skulls more complex.

Read more: https://www.eurekalert.org/news-releases/964000



Science Photo Library / Alamy Stock Photo image ID (2G70HK2) Original artist: Mark Garlick

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Ancient Fish Fossil Suggests That Teeth Didn't Evolve From Inside The Mouth

28 August 2022

There are two theories about where teeth originated: They either evolved from external scales (the outside-in hypothesis) or from somewhere inside the mouth (the inside-out hypothesis).

Researchers studying a fossil of the Ischyrhiza mira species – an extinct sawfish that lived in North America around 65 to 100 million years ago – have found more evidence backing up the outside-in idea.

Like the sawsharks and sawfishes of today, the creature had jagged spikes around its snout to help ward off predators and forage for food. It's thought that these spikes, called rostral denticles, are modified versions of the scales on the rest of the body.

https://www.sciencealert.com/ancient-fi ... -the-mouth



A rostral denticle of I. mia. (Todd Cook/Penn State/Wiley Publications)

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Earliest gibbon fossil found in southwest China
https://phys.org/news/2022-09-earliest- ... china.html
by New York University

A team of scientists has discovered the earliest gibbon fossil, a find that helps fill a long-elusive evolutionary gap in the history of apes.

The work, reported in the Journal of Human Evolution, centers on hylobatids, a family of apes that includes 20 species of living gibbons, which are found throughout tropical Asia from northeastern India to Indonesia.

"Hylobatids fossil remains are very rare, and most specimens are isolated teeth and fragmentary jaw bones found in cave sites in southern China and southeast Asia dating back no more than 2 million years ago," explains Terry Harrison, a professor of anthropology at New York University and one of the paper's authors. "This new find extends the fossil record of hylobatids back to 7 to 8 million years ago and, more specifically, enhances our understanding of the evolution of this family of apes."

The fossil, discovered in the Yuanmou area of Yunnan Province in southwestern China, is of a small ape called Yuanmoupithecus xiaoyuan. The analysis, which included Xueping Ji of the Kunming Institute of Zoology and the lead author of the study, focused on the teeth and cranial specimens of Yuanmoupithecus, including an upper jaw of an infant that was less than 2 years old when it died.

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Prehistoric Puke Reveals a Stomach-Churning Banquet From Millions of Years Ago
by Jennifer Nalewicki
September 15, 2022

Introduction:

(Science Alert) Hundreds of millions of years ago, a carnivorous critter gorged on a feast of prehistoric amphibians – and puked up its meal afterward.

Now, paleontologists have unearthed the regurgitation and published their findings of the ancient upchuck.

In 2018, researchers discovered the regurgitalite – fossilized remains of an animal's stomach contents, also known as a bromalite – during an excavation in the southeastern Utah portion of the Morrison Formation.

This swath of sedimentary rocks that stretches across the Western United States is a hotbed for fossils dating to the late Jurassic period (164 million to 145 million years ago).

This section in particular, dubbed the "Jurassic salad bar" by local paleontologists, typically contains the fossilized remains of plants and other organic matter, rather than animal bones.

Read more here: https://www.sciencealert.com/prehistor ... years-ago

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380-million-year-old heart illuminates evolutionary history
https://phys.org/news/2022-09-million-y ... story.html
by Curtin University

Researchers have discovered a 380-million-year-old heart—the oldest ever found—alongside a separate fossilized stomach, intestine and liver in an ancient jawed fish, shedding new light on the evolution of our own bodies.

The new research, published today in Science, found that the position of the organs in the body of arthrodires—an extinct class of armored fishes that flourished through the Devonian period from 419.2 million years ago to 358.9 million years ago—is similar to modern shark anatomy, offering vital new evolutionary clues.

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Researchers discover extinct prehistoric reptile that lived among dinosaurs
https://phys.org/news/2022-09-extinct-p ... saurs.html
by Smithsonian

Smithsonian researchers have discovered a new extinct species of lizard-like reptile that belongs to the same ancient lineage as New Zealand's living tuatara. A team of scientists, including the National Museum of Natural History's curator of Dinosauria Matthew Carrano and research associate David DeMar Jr. as well as University College London and Natural History Museum, London scientific associate Marc Jones, describe the new species Opisthiamimus gregori, which once inhabited Jurassic North America about 150 million years ago alongside dinosaurs like Stegosaurus and Allosaurus, in a paper published today in the Journal of Systematic Palaeontology. In life, this prehistoric reptile would have been about 16 centimeters (about 6 inches) from nose to tail—and would fit curled up in the palm of an adult human hand—and likely survived on a diet of insects and other invertebrates.

"What's important about the tuatara is that it represents this enormous evolutionary story that we are lucky enough to catch in what is likely its closing act," Carrano said. "Even though it looks like a relatively simple lizard, it embodies an entire evolutionary epic going back more than 200 million years."

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380-million-year-old heart illuminates evolutionary history
https://phys.org/news/2022-09-million-y ... story.html
by Curtin University

...

More on that:
Discovery of Oldest Fossil Heart Puts Organ At 380 Million Years Old
by Rachael Funnel
September 15, 2022

Introduction:

(IFL Science) The oldest heart known to science has been discovered in the remains of an ancient, jawed fish, along with a stomach, intestine, and liver to boot. The 380 million-year-old fish organ smashes previous records by a comfortable 250 million years and is shedding light on the evolution of even human bodies.

It comes from an extinct class of armored fishes, arthrodires, which were swimming about around between 419.2 to 358.9 million years ago. Despite its ancient origins, the discovery of a selection of its organs has shown that its body anatomy wasn’t that dissimilar to sharks alive today, revealing the ancient origins of their evolution.

“Evolution is often thought of as a series of small steps, but these ancient fossils suggest there was a larger leap between jawless and jawed vertebrates,” said Professor Kate Trinajstic, lead researcher from Curtin’s School of Molecular and Life Sciences and the Western Australian Museum, in a statement.

“These fish literally have their hearts in their mouths and under their gills – just like sharks today.”

The specimen is not only remarkable in its age but also that it was preserved in its 3D form, something which the researchers didn’t become completely aware of until they were at the scanning stage.

Read more of the IFL Science article here: https://www.iflscience.com/discovery-o ... old-65353

Here is a link to the statement by Professor Kate Trinajstic of Curtin’s School of Molecular and Life Sciences and the Western Australian Museum: https://www.scimex.org/newsfeed/new-cu ... evolution

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Earth's First Continents Sank into the Planet Before Rising Up Again
by Michele Starr
September 20, 2022

Introduction:

(Science Alert) A new examination of some of the oldest rocks in the world suggests that the first continents on Earth were unstable, and sank back into the mantle before making their way out again and reforming.

This could explain some of the more puzzling characteristics of cratons, extremely old and stable parts of the lithosphere (the crust and uppermost mantle) that have survived continental changes over eons and record Earth's ancient history.

The new findings could help us understand Earth's changing geology over its 4.5-billion-year lifespan.

"The rocks in the core of the continents, called cratons, are more than three billion years old," explains geologist Fabio Capitanio of the Monash University School of Earth, Atmosphere and Environment in Australia.

"They formed in the early Earth and hold the secret to how continents and the planet changed over time."

Read more here: https://www.sciencealert.com/earths-fi ... 0time.%22

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Three Major Aquatic Animal Groups Can Trace Their Lineage to This Ancient Armored 'Worm'
by Patrick Pester
October 1, 2022

Introduction:

(Science Alert) A bristly armored "worm" that scuttled across ocean reefs 518 million years ago is the ancestor to three aquatic animal groups that today live very different lifestyles, and it offers new clues about the explosion of diverse species at the time, a new study finds.

An international team of researchers recently discovered the fossil of a species that gave rise to brachiopods, bryozoans, and phoronids; these three groups of filter-feeding marine creatures all fix themselves to the seafloor, but each group has highly specialized feeding structures and they look very different from one another.

The fossil species, named Wufengella bengtsoni, is a member of an older, shelled group of organisms called tommotiids, scientists reported in a new study.

The find adds a new piece to the puzzle of how animals evolved during the Cambrian explosion, a time during the Cambrian period (541 million to 485.4 million years ago) when early life diversified rapidly on Earth, introducing and establishing a variety of different body plans that we still see in living animals today.

Brachiopods are shelled, bivalved creatures; bryozoans are soft-bodied with crowns of tentacles, and phoronids are encased in protective tubes made of chitin, a material that reinforces organic structures such as exoskeletons, beaks, and shells.

Read more here: https://www.sciencealert.com/3-major-a ... ored-worm

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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.

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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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Ancient Chemistry May Explain Why Living Things Use ATP as the Universal Energy Currency
October 4, 2022

Introduction:

(EurekAlert) A simple two-carbon compound may have been a crucial player in the evolution of metabolism before the advent of cells, according to a new study published October 4th in the open access journal PLOS Biology, by Nick Lane and colleagues of University College London, UK. The finding potentially sheds light on the earliest stages of prebiotic biochemistry, and suggests how ATP came to be the universal energy carrier of all cellular life today.

ATP, adenosine triphosphate, is used by all cells as an energy intermediate. During cellular respiration, energy is captured when a phosphate is added to ADP (adenosine diphosphate) to generate ATP; cleavage of that phosphate releases energy to power most types of cellular functions. But building ATP’s complex chemical structure from scratch is energy intensive and requires six separate ATP-driven steps; while convincing models do allow for prebiotic formation of the ATP skeleton without energy from already-formed ATP, they also suggest ATP was likely quite scarce, and that some other compound may have played a central role in conversion of ADP to ADP at this stage of evolution.

The most likely candidate, Lane and colleagues believed, was the two-carbon compound acetyl phosphate (AcP), which functions today in both bacteria and archaea as a metabolic intermediate. AcP has been shown to phosphorylate ADP to ATP in water in the presence of iron ions, but a host of questions remained after that demonstration, including whether other small molecules might work as well, whether AcP is specific for ADP or instead could function just as well with diphosphates of other nucleosides (such as guanosine or cytosine), and whether iron is unique in its ability to catalyze ADP phosphorylation in water.

In their new study, the authors explored all these questions. Drawing on data and hypotheses about the chemical conditions of the Earth before life arose, they tested the ability of other ions and minerals to catalyze ATP formation in water; none were nearly as effective as iron. Next, they tested a panel of other small organic molecules for their ability to phosphorylate ADP; none were as effective as AcP, and only one other (carbamoyl phosphate) had any significant activity at all. Finally, they showed that none of the other nucleoside diphosphates accepted a phosphate from AcP.

Read more here: https://www.eurekalert.org/news-releases/965354