February 2021

Petrified Tree Up to 20 Million Years Old Found Intact in Lesbos

<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-DV9FFV5uNgI/YDvGtqadl7I/AAAAAAAAS4c/Kb03THJaYgoHx7WNOuz2dZK3XpmSJ_IFQCLcBGAsYHQ/s1200/Petrified%2BTree%2BUp%2Bto%2B20%2BMillion%2BYears%2BOld%2BFound%2BIntact%2Bin%2BLesbos%2B%25281%2529.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="675" data-original-width="1200" height="360" src="https://1.bp.blogspot.com/-DV9FFV5uNgI/YDvGtqadl7I/AAAAAAAAS4c/Kb03THJaYgoHx7WNOuz2dZK3XpmSJ_IFQCLcBGAsYHQ/w640-h360/Petrified%2BTree%2BUp%2Bto%2B20%2BMillion%2BYears%2BOld%2BFound%2BIntact%2Bin%2BLesbos%2B%25281%2529.jpg" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">A fossilised tree trunk in the petrified forest of Lesbos. Photograph: Nikolas Zouros </td></tr></tbody></table> Discovery of 19.5-metre tree with roots, branches and leaves is unprecedented, say experts Greek scientists on the volcanic island of Lesbos say they have found a rare fossilized tree whose branches and roots are still intact after 20 million years. The tree was found during roadwork near an ancient forest petrified millions of years ago on the eastern Mediterranean island and transported from the site using a special splint and metal platform. It is the first time a tree has been found in such good condition complete with branches and roots since excavations began in 1995, said Professor Nikos Zouros of the Museum of Natural History of the Petrified Forest of Lesbos. “It is a unique find,” he said. “[It] is preserved in excellent condition and from studying the fossilized wood we will be able to identify the type of plant it comes from.” Lesbos’ petrified forest, a 15,000-hectare, UNESCO-protected site, is the result of a volcanic eruption 20 million years ago which smothered the island’s then subtropical forest ecosystem in lava. The fossilized tree, about 19 metres long, was preserved by a thick layer of volcanic ash after it fell. A large number of fruit tree leaves were found in the same spot, adding to the picture along with animal bones from the general area. “During the excavations the various forests that existed between 17 and 20 million years ago on Lesbos are being uncovered and we can reconstruct the ecosystem that existed during that period,” said Zouros.Excavations by his 35-strong team along a 20km highway connecting Sigri with Kalloni, the region’s biggest town, since 2013 have yielded more than 15 significant fossil sites but the earlier finds have paled next to the most recent. The discovery of an entire tree lying on a bed of leaves was not only unprecedented but down to pure luck. “Constructors were about to asphalt that part of the highway when one of our technicians noticed a tiny branch. The road work stopped, we starting excavating and quite quickly realised we had chanced upon an incredible find,” said Zouros. “It will now form part of the open-air museum we intend to create.” Geologists around the world have described the find as a breakthrough. “We have a case of extraordinary fossilisation in which a tree was preserved with its various parts intact. In the history of paleontology, worldwide, it’s unique,” said the Portuguese palaeontologist Artur Abreu Sá. “That it was buried by sediments expelled during a destructive volcanic eruption, and then found in situ, makes it even more unusual.” The climate emergency has highlighted the need to understand ecosystems in a hotter future if global temperatures are not reduced and, as such, Lesbos’s petrified forest offers an invaluable window into the past, said Prof Iain Stewart, who directs the Sustainable Earth Institute at the University of Plymouth. “It’s a world-class place to look at the type of environment that existed 20m years ago,” he told the Guardian. “Finds like these are a window into a particular past, a greenhouse, hothouse world, that existed back then. They might be an indication of what is coming if we don’t get our act together in tackling the climate change emergency.” In more recent times, Lesbos has been better known for the thousands of refugees who have landed on its shores but the island’s unusually diverse landscape and vegetation also draws scientists interested in its geological past. “The petrified forest is the first stop on our fieldtrip,” said Chronis Tzedakis, a professor of physical geography at University College London, who has been running field classes on the Aegean isle for the past decade. “It never disappoints … These new finds are stunning. The tree with its branches still attached is a rarity, while 150 trunks recovered together will provide a snapshot of a forest community which will allow us to assess its biodiversity at one point in time.” It was in Lesbos that Aristotle worked on the zoological studies that would become the canon of biological thought for the next 2,000 years. Tzedakis has found himself pondering whether the philosopher who was invited to the island by his disciple, Theophrastus, was ultimately influenced by the geological wonder. The polymath, himself a student of Plato, spent two years there, much of it ensconced in the study of marine biology. “I often like to think that Aristotle, who established the foundation of scientific inquiry while on Lesbos must have seen the petrified trees of Sigri,” he said adding that the similarity of some of the fossils to their living relatives may have inspired his theory of species being fixed and well-defined. “Having grown up in nearby Eressos, Theophrastus, the ‘father of botany’, would have surely known about it and have taken the great man to see it.”

Petrified Tree Up to 20 Million Years Old Found Intact in Lesbos

A fossilised tree trunk in the petrified forest of Lesbos. Photograph: Nikolas Zouros Discovery of 19.5-metre tree with roots, branches and ...

Earth's Magnetic Field Flipped 42,000 Years Ago. The Consequences Were Dramatic

<div class="separator" style="clear: both; text-align: center;"><a href="https://1.bp.blogspot.com/-n94HcCtelLs/YDUocPeQuwI/AAAAAAAAS34/CqdHC0bKI_8K3pjOyGugGmT_Hopp9StbQCLcBGAsYHQ/s1200/Earth%2527s%2BMagnetic%2BField%2BFlipped%2B42%252C000%2BYears%2BAgo.%2BThe%2BConsequences%2BWere%2BDramatic%2B%25282%2529.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="900" data-original-width="1200" height="480" src="https://1.bp.blogspot.com/-n94HcCtelLs/YDUocPeQuwI/AAAAAAAAS34/CqdHC0bKI_8K3pjOyGugGmT_Hopp9StbQCLcBGAsYHQ/w640-h480/Earth%2527s%2BMagnetic%2BField%2BFlipped%2B42%252C000%2BYears%2BAgo.%2BThe%2BConsequences%2BWere%2BDramatic%2B%25282%2529.jpg" width="640" /></a></div>  A global period of upheaval 42,000 years ago was the result of a reversal in Earth's magnetic field, new research has found. According to radiocarbon preserved in ancient tree rings, several centuries' worth of climate breakdown, mass extinctions, and even changes in human behaviour can be directly linked to the last time Earth's magnetic field changed its polarity. The research team has named the period the Adams Transitional Geomagnetic Event, or Adams Event, after sci-fi writer Douglas Adams, who famously declared the number 42 the ultimate answer to life, the Universe, and everything. "For the first time ever, we have been able to precisely date the timing and environmental impacts of the last magnetic pole switch," said Earth scientist Chris Turney of the University of New South Wales in Australia. "The findings were made possible with ancient New Zealand kauri trees, which have been preserved in sediments for over 40,000 years. Using the ancient trees we could measure, and date, the spike in atmospheric radiocarbon levels caused by the collapse of Earth's magnetic field." <div style="margin: 0px auto; width: 100%;">
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</div> This most recent period of magnetic reversal is known as the Laschamp event, and it is what we call a geomagnetic excursion. This is when the planet's magnetic poles briefly swap places before returning to their original positions. It's one of the most well studied of Earth's magnetic field events, recorded by ferromagnetic minerals. It took place around 41,000 years ago, and lasted for around 800 years. Exactly what impact this event had on life on the planet was unclear, though - so when scientists uncovered an ancient kauri tree (Agathis australis) in 2019 that had been alive during this time period, they seized on the chance to learn more. That's because trees record atmospheric activity in their annual growth rings. In particular, carbon-14, or radiocarbon, can reveal a lot of information about celestial activity. Radiocarbon only occurs on Earth in trace amounts compared to the other naturally occurring carbon isotopes. It's formed in the upper atmosphere under the bombardment of cosmic rays from space. When these rays enter the atmosphere, they interact with the local nitrogen atoms to trigger a nuclear reaction that produces radiocarbon. Since cosmic rays are constantly streaming through space, Earth receives a more or less steady supply of radiocarbon. Therefore, a spike in radiocarbon in tree rings tells us that Earth had greater exposure to radiocarbon during that year. When Earth's magnetic field is weakened, as it was during the Laschamp event, more cosmic rays penetrate through to the atmosphere to produce more radiocarbon. Because of this, scientists had previously been able to ascertain that Earth's magnetic field had weakened to about 28 percent of its normal strength during that 800-year period. The kauri tree, however, allowed the research team to study the years leading up to the Laschamp event. They found that the Adams event took place from about 42,200 years ago, and the magnetic field was at its weakest point before the Laschamp event. "Earth's magnetic field dropped to only 0-6 percent strength during the Adams Event," Turney explained. "We essentially had no magnetic field at all - our cosmic radiation shield was totally gone." During this time, the Sun's magnetic field would also have weakened several times, as it, too, experienced magnetic reversal as part of its regular cycle. These periods see less sunspot and flare activity, but the Sun's magnetic field also provides Earth with a measure of protection from cosmic rays - so, during these solar minima, cosmic ray bombardment would have increased again. This weakened magnetic field would have triggered substantial changes in Earth's atmospheric ozone, with dramatic consequences, including electrical storms and spectacular aurorae, and climate change around the world. "Unfiltered radiation from space ripped apart air particles in Earth's atmosphere, separating electrons and emitting light - a process called ionisation," Turney said. "The ionised air 'fried' the ozone layer, triggering a ripple of climate change across the globe." This is consistent with climate and environmental changes from this time observed in other records from across the globe, such as the mysterious extinction of Australia's megafauna. The research has been published in <a href="https://science.sciencemag.org/content/371/6531/811" rel="nofollow" target="_blank">Science</a>.

Earth's Magnetic Field Flipped 42,000 Years Ago. The Consequences Were Dramatic

A global period of upheaval 42,000 years ago was the result of a reversal in Earth's magnetic field, new research has found. According...

World's Oldest DNA Found in Siberian Mammoth Teeth

extinction, Fossils 8:02 PM

<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-AJb7HQbNAH4/YDKRqjam1NI/AAAAAAAAS3M/NLFLnfm0wDcPos0Run4murd0jsGYzc0TwCLcBGAsYHQ/s1220/World%2527s%2BOldest%2BDNA%2BFound%2Bin%2BSiberian%2BMammoth%2BTeeth%2B%25281%2529.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="871" data-original-width="1220" height="456" src="https://1.bp.blogspot.com/-AJb7HQbNAH4/YDKRqjam1NI/AAAAAAAAS3M/NLFLnfm0wDcPos0Run4murd0jsGYzc0TwCLcBGAsYHQ/w640-h456/World%2527s%2BOldest%2BDNA%2BFound%2Bin%2BSiberian%2BMammoth%2BTeeth%2B%25281%2529.jpg" title="World's Oldest DNA Found in Siberian Mammoth Teeth" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">An illustration of the mammoth.</td></tr></tbody></table>  Scientists have recovered DNA from mammoth fossils found in Siberian permafrost that are more than a million years old. This DNA—the oldest genomic evidence recovered to date—illuminates the evolutionary history of woolly mammoths and Columbian mammoths. It also raises the prospect of recovering DNA from other organisms this ancient—including extinct members of the human family. Ever since the recovery of two short DNA sequences from a recently extinct zebra subspecies known as the quagga in 1984, researchers have been working to get ever larger amounts of DNA from ever older remains. Advances in ancient DNA extraction and sequencing methods eventually brought to light genomes of creatures from deeper time, including cave bears and Neandertals. In 2013, investigators announced that they had retrieved DNA from a 700,000-year-old horse fossil—by far the oldest genomic data ever obtained. But as astonishingly old as that genetic material was, some experts predicted that sequenceable DNA should survive more than a million years in fossils preserved in frozen environments. The new findings, published today in Nature, bear that prediction out. Tom van der Valk and Love Dalén of the Center for Paleogenetics in Stockholm and their colleagues obtained DNA from molar teeth belonging to three mammoths from different time periods. Mammoth species can be distinguished on the basis of dental characteristics. One tooth, discovered in deposits thought to be around 700,000 years old, looked like that of an early woolly mammoth, Mammuthus primigenius. The other two teeth—one dated to around one million years ago and the other to 1.2 million years ago or more—resembled molars of the steppe mammoth, Mammuthus trogontherii. The genetic material extracted from the teeth was highly degraded, having fragmented into lots of tiny pieces over the millennia. To reassemble the pieces and help filter out any DNA from microbes or other contaminants, the researchers used the genomes of modern-day elephants as guides, much as someone solving a jigsaw puzzle might refer to the image on the box. In all they recovered billions of DNA base pairs from the youngest fossil (the woolly mammoth)—about 70 to 80 percent of the genome. They got hundreds of millions of base pairs constituting around 25 to 30 percent of the genome of the second oldest mammoth. The oldest fossil yielded the least DNA, but the team still sequenced around 60 million base pairs from it—enough to provide insights into mammoth evolution. The fossil record of mammoths indicates that they arose around five million years ago in Africa and spread across much of the world, evolving into number of species and enduring for millions of years before going extinct just a few thousand years ago. Comparing the new genomic data to genomes of younger mammoths, the researchers confirmed their expectation that the woolly mammoth evolved from the steppe mammoth, and they showed that it gradually acquired its adaptations to the extreme cold of ice age Siberia. The results also revealed surprises about another branch of the mammoth family tree. The oldest mammoth the team sampled turned out to belong to a previously unknown lineage that was ancestral to the mammoths that colonized North America 1.5 million years ago during the early Pleistocene epoch and gave rise to the Columbian mammoth that inhabited temperate regions of North and Central America. The Columbian mammoth may have been the product of interbreeding between woolly mammoths and members of the lineage to which the researchers’ oldest fossil specimen belonged, they suggest. Outside experts say the work represents a significant advance in ancient DNA research. “It’s an exciting study revealing DNA survival beyond what many in the field would have predicted being the upper limit just a decade ago,” remarks Eske Willerslev of the University of Copenhagen, whose team recovered the 700,000-year-old horse genome in 2013. He and his colleagues were among the researchers who calculated that DNA more than a million years old could survive in permafrost conditions. “Now this has been proven,” he says. “This is a very exciting study, not only because it pushes back the age of the oldest DNA yet recovered, but because the DNA that the team obtained from these very ancient mammoths provides important insights into early mammoth populations and into the origins of later mammoths both in Europe and the Americas,” says Janet Kelso of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. Mammoths are not the only creatures of interest from this time period. Dalén, van der Valk and their colleagues note that many modern-day mammal and bird species got their start in the Early and Middle Pleistocene. At a press teleconference on February 16, Dalén said that the team is starting projects looking into some of these species, including horses, musk ox and various rodents. Can scientists expect to recover DNA from similarly ancient human ancestors? The human fossil record spans up to seven million years. The oldest human DNA comes from remains dated to 430,000 years ago. “We know that environmental conditions matter a lot for the preservation of DNA. The extraordinary preservation of these mammoth specimens is likely thanks to the fact that they have been ‘on-ice’—frozen in Northern Siberia since the death of these mammoths,” says Kelso, who has studied a number of ancient human genomes. “The ancient humans that have been discovered so far are not found in such ideal conditions, and our view back into the human past is unfortunately therefore still limited.” But all hope is not lost. “Every year there are new innovations in methods,” Dalén said at the press teleconference. “Maybe a number of years in the future the methods will be there to recover DNA from human nonpermafrost specimens that are getting close to a million years old.” Alternatively, he added, “it is quite possible that in the future someone will find human remains frozen in permafrost of that age.  The study was published in the journal <a href="https://www.nature.com/articles/d41586-021-00436-x#ref-CR1" rel="nofollow" target="_blank">Nature.</a>

World's Oldest DNA Found in Siberian Mammoth Teeth

An illustration of the mammoth. Scientists have recovered DNA from mammoth fossils found in Siberian permafrost that are more than a milli...

Researchers Find Ingredients for Microbial Life in 3.5-Billion-Year-Old Rocks

Earth History, evolution 7:39 PM

<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-gK8RSlKXMqY/YDE6g6lELqI/AAAAAAAAS3A/QfjXsAafBY409_mtnB4RBHadmUCmY9XdACLcBGAsYHQ/s1500/Researchers%2BFind%2BIngredients%2Bfor%2BMicrobial%2BLife%2Bin%2B3.5-Billion-Year-Old%2BRocks%2B%25281%2529.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="779" data-original-width="1500" height="332" src="https://1.bp.blogspot.com/-gK8RSlKXMqY/YDE6g6lELqI/AAAAAAAAS3A/QfjXsAafBY409_mtnB4RBHadmUCmY9XdACLcBGAsYHQ/w640-h332/Researchers%2BFind%2BIngredients%2Bfor%2BMicrobial%2BLife%2Bin%2B3.5-Billion-Year-Old%2BRocks%2B%25281%2529.jpg" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">The close association between the inclusion-bearing black barites and stromatolites suggests that hydrothermal fluids might have influenced ancient microbial communities. Image credit: Mißbach et al.</td></tr></tbody></table>A team of geobiologists from Germany has found biologically-relevant primordial organic molecules and gases in fluid inclusions trapped in 3.5-billion-year-old barites from the Dresser mine, Marble Bar, Australia. A research team including the geobiologist Dr. Helge Missbach from the University of Cologne has detected organic molecules and gases trapped in 3.5-billion-year-old rocks. A widely accepted hypothesis says that the earliest life forms used small organic molecules as building materials and energy sources. However, the existence of such components in early habitats on Earth was as yet unproven. The current study, published in the journal Nature Communications, shows that solutions from archaic hydrothermal vents contained essential components that formed a basis for the earliest life on our planet. Specifically, the scientists examined about 3.5-billion-year-old barites from the Dresser Formation in Western Australia. The barite thus dates from a time when early life developed on Earth. "In the field, the barites are directly associated with fossilized microbial mats, and they smell like rotten eggs when freshly scratched. Thus, we suspected that they contained organic material that might have served as nutrients for early microbial life," said Dr. Helge Missbach of the Institute of Geology and Mineralogy and lead author of the study. In the fluid inclusions, the team identified organic compounds such as acetic acid and methanethiol, in addition to gases such as carbon dioxide and hydrogen sulfide. These compounds may have been important substrates for metabolic processes of early microbial life. Furthermore, they are discussed as putative key agents in the origin of life on Earth. "The immediate connection between primordial molecules emerging from the subsurface and the microbial organisms—3.5 billion years ago—somehow surprised us. This finding contributes decisively to our understanding of the still unclear earliest evolutionary history of life on Earth," Missbach concluded.  The above story is based on <a href="https://portal.uni-koeln.de/en/universitaet/aktuell/press-releases/single-news/fuel-for-earliest-life-forms-organic-molecules-found-in-35-billion-year-old-rocks" rel="nofollow" style="-webkit-text-stroke-width: 0px; background-color: white; border-radius: 0px !important; box-sizing: border-box; font-size: 14px; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px;" target="_blank">Materials</a><span style="-webkit-text-stroke-width: 0px; background-color: white; display: inline !important; float: none; font-size: 14px; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-decoration-color: initial; text-decoration-style: initial; text-decoration-thickness: initial; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px;"> provided by <a href="https://portal.uni-koeln.de/en/uoc-home" rel="nofollow" style="-webkit-text-stroke-width: 0px; background-color: white; border-radius: 0px !important; box-sizing: border-box; font-size: 14px; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px;" target="_blank">University of Cologne</a><span style="-webkit-text-stroke-width: 0px; background-color: white; color: #333333; display: inline !important; float: none; font-family: "Helvetica Neue", Helvetica, Arial, sans-serif; font-size: 14px; font-style: normal; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-decoration-color: initial; text-decoration-style: initial; text-decoration-thickness: initial; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px;">.

Researchers Find Ingredients for Microbial Life in 3.5-Billion-Year-Old Rocks

The close association between the inclusion-bearing black barites and stromatolites suggests that hydrothermal fluids might have influenced ...

A New, Clearer Insight Into Earth's Hidden Crystals

earth, Geochemistry, Tectonic 6:55 PM

<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-UIxIXJBHiMQ/YC6NRI9EObI/AAAAAAAAS2g/w_bP3wFAqjs_RzcaxFdX9nPikWz-bcu5QCLcBGAsYHQ/s1200/A%2BNew%252C%2BClearer%2BInsight%2BInto%2BEarth%2527s%2BHidden%2BCrystals%2B%25281%2529.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="Olivine - rock-forming mineral of Dunite" border="0" data-original-height="518" data-original-width="1200" height="276" src="https://1.bp.blogspot.com/-UIxIXJBHiMQ/YC6NRI9EObI/AAAAAAAAS2g/w_bP3wFAqjs_RzcaxFdX9nPikWz-bcu5QCLcBGAsYHQ/w640-h276/A%2BNew%252C%2BClearer%2BInsight%2BInto%2BEarth%2527s%2BHidden%2BCrystals%2B%25281%2529.jpg" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">Olivine - rock-forming mineral of Dunite</td></tr></tbody></table> Geologists have developed a new theory about the state of Earth billions of years ago after examining the very old rocks formed in the Earth's mantle below the continents. Assistant Professor Emma Tomlinson from Trinity College Dublin and Queensland University of Technology's Professor Balz Kamber have just published their research in leading international journal, Nature Communications. The seven continents on Earth today are each built around a stable interior called a craton, and geologists believe that craton stabilisation some 2.5 -- 3 billion years ago was critical to the emergence of land masses on Earth. Little is known about how cratons and their supporting mantle keels formed, but important clues can be found in peridotite xenoliths, which are samples of mantle that are brought to the Earth's surface by erupting volcanoes. Dr Tomlinson, from Trinity's School of Natural Sciences, said: "Many rocks from the mantle below old continents contain a surprising amount of silica -- much more than is found in younger parts of the mantle." "There is currently no scientific consensus about the reason for this." The new research, which looks at the global data for mantle peridotite, comes up with a new explanation for this observation. The research used a new thermodynamic model to calculate that the unusual mineralogy developed when very hot molten rock -- greater than 1700 °C -- interacted with older parts of the mantle and this caused the growth of silica-rich minerals. "For more than 1 billion years, from 3.8 to 2.5 billion years ago, volcanoes also erupted very unusual lavas of very low viscosity -- lava that was very thin, very hot and often contained variable levels of silica," Dr Tomlinson added. "Our modelling suggests that the unusual lavas were in fact the molten rocks that interacted with the mantle at great depth and this interaction resulted in the variable level of silica." Professor Kamber, QUT, said: "Both the silica-rich rocks in the deep mantle and the low viscosity volcanic rocks stopped being made by the Earth some 2.5 billion years ago. This timing is the boundary between the Archaean and Proterozoic eons -- one of the most significant breaks in Earth's geological timescale." What caused this boundary remains unknown, but the research offers a new perspective. Professor Kamber added: "This may have been due to a change in how the mantle was flowing. Once the mantle started slowly turning over all the way down to the core (2,900 km), the very high temperatures of the Archaean eon were no longer possible."  The above story is based on <a href="https://www.tcd.ie/news_events/articles/a-new-clearer-insight-into-earths-hidden-crystals/" rel="nofollow" style="-webkit-text-stroke-width: 0px; background-color: white; border-radius: 0px !important; box-sizing: border-box; font-size: 14px; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px;" target="_blank">Materials</a><span style="-webkit-text-stroke-width: 0px; background-color: white; display: inline !important; float: none; font-size: 14px; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-decoration-color: initial; text-decoration-style: initial; text-decoration-thickness: initial; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px;"> provided by<span style="-webkit-text-stroke-width: 0px; background-color: white; display: inline !important; float: none; font-size: 14px; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-decoration-color: initial; text-decoration-style: initial; text-decoration-thickness: initial; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px;"> <a href="http://www.tcd.ie/" rel="nofollow" style="-webkit-text-stroke-width: 0px; background-color: white; border-radius: 0px !important; box-sizing: border-box; font-size: 14px; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px;" target="_blank">Trinity College Dublin</a><span style="-webkit-text-stroke-width: 0px; background-color: white; display: inline !important; float: none; font-size: 14px; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-decoration-color: initial; text-decoration-style: initial; text-decoration-thickness: initial; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px;">.

A New, Clearer Insight Into Earth's Hidden Crystals

Olivine - rock-forming mineral of Dunite Geologists have developed a new theory about the state of Earth billions of years ago after examini...

Mount Etna: Europe's Most Active Volcano Explodes and Closes Nearby Airport

News, volcano 6:56 PM

Mount Etna: Europe's Most Active Volcano Explodes and Closes Nearby Airport

On Tuesday there was a major increase in volcanic activity at the Southeast Crater, followed by a violent pyroclastic flow accompanied by ta...

Thai Fisherman Finds Rare Orange Pearl Worth $330k

famous, gemstones 7:19 PM

Thai Fisherman Finds Rare Orange Pearl Worth $330k

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635 Million-Year-Old Fossil Is the Oldest Known Land Fungus

Earth History, Fossils 7:35 PM

<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-4Q9kjRVp5OI/YBrQJ5XM7vI/AAAAAAAAS1M/4YAMfbixwN0X8TBvuTieIsxyAYrev-m9ACLcBGAsYHQ/s1202/635%2BMillion-Year-Old%2BFossil%2BIs%2Bthe%2BOldest%2BKnown%2BLand%2BFungus%2B%25281%2529.jpg" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="843" data-original-width="1202" height="448" src="https://1.bp.blogspot.com/-4Q9kjRVp5OI/YBrQJ5XM7vI/AAAAAAAAS1M/4YAMfbixwN0X8TBvuTieIsxyAYrev-m9ACLcBGAsYHQ/w640-h448/635%2BMillion-Year-Old%2BFossil%2BIs%2Bthe%2BOldest%2BKnown%2BLand%2BFungus%2B%25281%2529.jpg" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">Microscopic image of the fungus-like microfossils. (Image: © Andrew Czaja of University of Cincinnati)</td></tr></tbody></table> The oldest evidence of land fungus may be a wee microfossil that's 635 million years old, found in a cave in southern China.When you think of fungi, what comes to mind may be a crucial ingredient in a recipe or their amazing ability to break down dead organic matter into vital nutrients. But new research by Shuhai Xiao, a professor of geosciences with the Virginia Tech College of Science, and Tian Gan, a visiting Ph.D. student in the Xiao lab, highlights yet another important role that fungi have played throughout the Earth's history: helping the planet recover from an ice age. A team of scientists from Virginia Tech, the Chinese Academy of Sciences, Guizhou Education University, and University of Cincinnati has discovered the remains of a fungi-like microfossil that emerged at the end of an ice age some 635 million years ago. It is the oldest terrestrial fossil ever found. To put it into perspective, this microfossil predates the oldest dinosaurs about three times over. The fossil was found in small cavities within well-studied sedimentary dolostone rocks of the lowermost Doushantuo Formation in South China. Although the Doushantuo Formation has provided a plethora of fossils to date, researchers did not expect to find any fossils toward the lower base of the dolostones. But against all odds, Gan found a few long, thread-like filaments -- one of the key characteristics of fungi. "It was an accidental discovery," said Gan. "At that moment, we realized that this could be the fossil that scientists have been looking for a long time. If our interpretation is correct, it will be helpful for understanding the paleoclimate change and early life evolution." This discovery is key for understanding multiple turning points throughout Earth's history: the Ediacaran period and the terrestrialization of fungi. When the Ediacaran period began, the planet was recovering from a catastrophic ice age, also known as the "snowball Earth." At that time, ocean surfaces were frozen to a depth of more than a kilometer and it was an incredibly harsh environment for virtually any living organism, except for some microscopic life that managed to thrive. Scientists have long wondered how life ever returned to normalcy -- and how the biosphere was able to grow larger and more complex than ever before. With this new fossil in hand, Tian and Xiao are certain that these microscopic, low profile cave dwellers played numerous roles in the reconditioning of the terrestrial environment in the Ediacaran time. One role involved their formidable digestive system. Fungi have a rather unique digestive system that plays an even greater role in the cycling of vital nutrients. Using enzymes secreted into the environment, terrestrial fungi can chemically break down rocks and other tough organic matter, which can then be recycled and exported into the ocean. "Fungi have a mutualistic relationship with the roots of plants, which helps them mobilize minerals, such as phosphorus. Because of their connection to terrestrial plants and important nutritional cycles, terrestrial fungi have a driving influence on biochemical weathering, the global biogeochemical cycle, and ecological interactions," said Gan. Although previous evidence stated that terrestrial plants and fungi formed a symbiotic relationship around 400 million years ago, this new discovery has recalibrated the timeline of when these two kingdoms colonized the land. "The question used to be: 'Were there fungi in the terrestrial realm before the rise of terrestrial plants'," said Xiao, an affiliated faculty member of the Fralin Life Sciences Institute and the Global Change Center. "And I think our study suggests yes. Our fungus-like fossil is 240 million years older than the previous record. This is, thus far, the oldest record of terrestrial fungi." Now, new questions have arisen. Since the fossilized filaments were accompanied by other fossils, Gan will set out to explore their past relationships. "One of my goals is to constrain the phylogenetic affinities of these other types of fossils that are associated with the fungal fossils," said Gan. Xiao is thrilled to tackle the environmental aspects of these microorganism. Sixty years ago, few believed that microorganisms, like bacteria and fungi, could be preserved as fossils. Now that Xiao has seen them with his very eyes, he plans to learn more about how they have been virtually frozen in time. "It is always important to understand the organisms in the environmental context," said Xiao. "We have a general idea that they lived in small cavities in dolostone rocks. But little is known about how exactly they lived and how they were preserved. Why can something like fungi, which have no bones or shells, be preserved in the fossil record?" However, it can't be said for sure if this fossil is a definitive fungus. Although there is a fair amount of evidence behind it, the investigation into these microfossils is ongoing. "We would like to leave things open for other possibilities, as a part of our scientific inquiry," said Xiao. "The best way to put it is that perhaps we have not disapproved that they are fungi, but they are the best interpretation that we have at the moment." Three distinct groups and labs at Virginia Tech were crucial for the identification and timestamping of this fossil. The Confocal Laser Scanning and Microscopy lab at the Fralin Life Sciences Institute helped Tian and Xiao perform initial analysis that prompted further investigation at the University of Cincinnati. The Department of Biological Sciences' Massey Herbarium, which houses over 115,000 specimens of vascular plants, fungi, bryophytes, and lichens, provided modern fungal specimens for comparison with the fossils. The team called in technicians to conduct geochemical analysis using Secondary Ion Mass Spectrometry, which ionize nanomoles of material from small areas that are a fraction the thickness of a hair strand, to analyze the isotopic abundance of sulfur-32 and sulfur-34 in order to understand the fossilization environment. Advanced computerized tomography was crucial to getting the 3D morphology of the filaments, which are just a few micrometers thick. And a combination of Focused Ion Beam Scanning Electron Microscopy and Transmission Electron Microscopy allowed researchers to cut samples with surgical precision and take an even closer look at every nanometer of the filaments. "This wasn't a single person or even a single lab that did this work," said Xiao. Xiao also emphasized the importance of interdisciplinary research in this study and many others. "It's very important to encourage the next generation of scientists to be trained in an interdisciplinary light because new discoveries always happen at the interface of different fields," said Xiao.  The above story is based on <a href="https://vtnews.vt.edu/articles/2021/01/fralinlifesci-oldest-fungi-like-microfossil-bailed-us-out-of-an-ice-age.html" rel="nofollow" style="-webkit-text-stroke-width: 0px; background-color: white; box-sizing: border-box; color: #337ab7; font-size: 14px; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px;" target="_blank">Materials</a><span style="-webkit-text-stroke-width: 0px; background-color: white; color: #333333; display: inline; float: none; font-size: 14px; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-decoration-color: initial; text-decoration-style: initial; text-decoration-thickness: initial; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px;"> provided by<span style="-webkit-text-stroke-width: 0px; background-color: white; color: #333333; display: inline; float: none; font-size: 14px; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-decoration-color: initial; text-decoration-style: initial; text-decoration-thickness: initial; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px;"> <a href="http://www.vt.edu/" rel="nofollow" style="-webkit-text-stroke-width: 0px; background-color: white; box-sizing: border-box; color: #337ab7; font-size: 14px; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px;" target="_blank">Virginia Tech</a><span style="-webkit-text-stroke-width: 0px; background-color: white; color: #333333; display: inline; float: none; font-size: 14px; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-decoration-color: initial; text-decoration-style: initial; text-decoration-thickness: initial; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px;">. Original written by Kendall Daniels.

635 Million-Year-Old Fossil Is the Oldest Known Land Fungus

Microscopic image of the fungus-like microfossils. (Image: © Andrew Czaja of University of Cincinnati) The oldest evidence of land fungus ma...

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