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RandiFan1290
RandiFan1290's Journal
RandiFan1290's Journal
December 19, 2019
The World's Oldest Forest Has 385-Million-Year-Old Tree Roots
https://www.smithsonianmag.com/science-nature/385-million-year-old-fossils-reveal-worlds-oldest-forest-had-modern-tree-roots-180973810/At three trillion strong, Earth’s trees are estimated to outnumber the stars in the Milky Way. These woody wonders sponge carbon dioxide out of the skies, brace soil against erosion, cycle water through ecosystems and support countless forms of life. And we largely have their sophisticated root systems to thank.
Sprouting from the base of tree trunks, roots are the arboreal equivalent of a digestive tract, exchanging water and nutrients with surrounding soils. Roots literally anchor a plant, and the more extensive they are, the bigger and stronger the stuff above ground can grow. In their modern forms, they helped trees dominate their habitats—and spread across the globe.
“Roots maximize [a tree’s] physiological capacity,” says Christopher Berry, a paleobotanist at Cardiff University in the United Kingdom. “An efficient rooting system is key to being a successful tree.”
Now, new research from Berry and his colleagues suggests the modern versions of these stupendous structures are more deeply rooted in the arboreal family tree than ever thought before. Their team has uncovered Earth’s oldest known forest outside Cairo, New York, as detailed today in the journal Current Biology. At 385 million years old, the ancient woodland predates the rise of seed-producing plants, a group that includes almost all living trees. The Paleozoic forest is also home to the remnants of intricate tree root systems that bear an uncanny resemblance to those still around today.
Sprouting from the base of tree trunks, roots are the arboreal equivalent of a digestive tract, exchanging water and nutrients with surrounding soils. Roots literally anchor a plant, and the more extensive they are, the bigger and stronger the stuff above ground can grow. In their modern forms, they helped trees dominate their habitats—and spread across the globe.
“Roots maximize [a tree’s] physiological capacity,” says Christopher Berry, a paleobotanist at Cardiff University in the United Kingdom. “An efficient rooting system is key to being a successful tree.”
Now, new research from Berry and his colleagues suggests the modern versions of these stupendous structures are more deeply rooted in the arboreal family tree than ever thought before. Their team has uncovered Earth’s oldest known forest outside Cairo, New York, as detailed today in the journal Current Biology. At 385 million years old, the ancient woodland predates the rise of seed-producing plants, a group that includes almost all living trees. The Paleozoic forest is also home to the remnants of intricate tree root systems that bear an uncanny resemblance to those still around today.
December 12, 2019
Earliest known cave art by modern humans found in Indonesia
https://www.theguardian.com/science/2019/dec/11/earliest-known-cave-art-by-modern-humans-found-in-indonesiaCave art depicting human-animal hybrid figures hunting warty pigs and dwarf buffaloes has been dated to nearly 44,000 years old, making it the earliest known cave art by our species.
The artwork in Indonesia is nearly twice as old as any previous hunting scene and provides unprecedented insights into the earliest storytelling and the emergence of modern human cognition.
Previously, images of this level of sophistication dated to about 20,000 years ago, with the oldest cave paintings believed to be more basic creations such as handprints.
The artwork in Indonesia is nearly twice as old as any previous hunting scene and provides unprecedented insights into the earliest storytelling and the emergence of modern human cognition.
Previously, images of this level of sophistication dated to about 20,000 years ago, with the oldest cave paintings believed to be more basic creations such as handprints.
August 1, 2019
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Harvard study reveals ancient Mesoamericans knowledge about Earth's magnetism
https://news.harvard.edu/gazette/story/2019/07/harvard-study-reveals-ancient-mesoamericans-knowledge-about-earths-magnetism/The purpose of Mesoamerican potbelly statues have been the subject of debate among anthropologists for decades: Are they depictions of the ruling elite? A way to honor dead ancestors? Or perhaps portrayals of women giving birth?
As the various theories wound their way through academic circles, the surprising discovery four decades ago that many of the statues, found in Guatemala, are magnetized in certain spots added a new dimension to those discussions.
And a Harvard study suggests that where those areas show up is no accident.
Led by Assistant Professor of Earth and Planetary Sciences Roger Fu, a team of researchers has shown that artisans carved the figures so that the magnetic areas fell at the navel or right temple — suggesting not only that Mesoamerican people were familiar with the concept of magnetism but also that they had some way of detecting the magnetized spots. The study is described in an April 12 paper published in the Journal of Archaeological Science.
As the various theories wound their way through academic circles, the surprising discovery four decades ago that many of the statues, found in Guatemala, are magnetized in certain spots added a new dimension to those discussions.
And a Harvard study suggests that where those areas show up is no accident.
Led by Assistant Professor of Earth and Planetary Sciences Roger Fu, a team of researchers has shown that artisans carved the figures so that the magnetic areas fell at the navel or right temple — suggesting not only that Mesoamerican people were familiar with the concept of magnetism but also that they had some way of detecting the magnetized spots. The study is described in an April 12 paper published in the Journal of Archaeological Science.
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March 11, 2019
'A big jump': People might have lived in Australia twice as long as we thought
https://www.theguardian.com/australia-news/postcolonial-blog/2019/mar/11/a-big-jump-people-might-have-lived-in-australia-twice-as-long-as-we-thoughtExtensive archaeological research in southern Victoria has again raised the prospect that people have lived in Australia for 120,000 years – twice as long as the broadly accepted period of human continental habitation.
The research, with its contentious potential implications for Indigenous habitation of the continent that came to be Australia, has been presented to the Royal Society of Victoria by a group of academics including Jim Bowler, the eminent 88-year-old geologist who in 1969 and 1974 discovered the bones of Mungo Lady and Mungo Man, the oldest human remains found in Australia.
Mungo Man, his remains discovered in a dry water bed in the Willandra Lakes district of New South Wales, lived some 42,000 years ago. He was a modern human or homo sapien, Indigenous to Australia, who was buried with sophisticated funerary rites including the use of fire and ochre.
Earlier contentious scientific research that pointed to human habitation in Australia up to 120,000 years ago – including in the Kimberley – has been largely dismissed.
The research, with its contentious potential implications for Indigenous habitation of the continent that came to be Australia, has been presented to the Royal Society of Victoria by a group of academics including Jim Bowler, the eminent 88-year-old geologist who in 1969 and 1974 discovered the bones of Mungo Lady and Mungo Man, the oldest human remains found in Australia.
Mungo Man, his remains discovered in a dry water bed in the Willandra Lakes district of New South Wales, lived some 42,000 years ago. He was a modern human or homo sapien, Indigenous to Australia, who was buried with sophisticated funerary rites including the use of fire and ochre.
Earlier contentious scientific research that pointed to human habitation in Australia up to 120,000 years ago – including in the Kimberley – has been largely dismissed.
December 26, 2018
Fossils suggest flowers originated 50 million years earlier than thought
https://www.sciencedaily.com/releases/2018/12/181218115205.htmScientists have described a fossil plant species that suggests flowers bloomed in the Early Jurassic, more than 174 million years ago, according to new research in the open-access journal eLife.
Before now, angiosperms (flowering plants) were thought to have a history of no more than 130 million years. The discovery of the novel flower species, which the study authors named Nanjinganthus dendrostyla, throws widely accepted theories of plant evolution into question, by suggesting that they existed around 50 million years earlier. Nanjinganthus also has a variety of 'unexpected' characteristics according to almost all of these theories.
Angiosperms are an important member of the plant kingdom, and their origin has been the topic of long-standing debate among evolutionary biologists. Many previously thought angiosperms could be no more than 130 million years old. However, molecular clocks have indicated that they must be older than this. Until now, there has been no convincing fossil-based evidence to prove that they existed further back in time.
"Researchers were not certain where and how flowers came into existence because it seems that many flowers just popped up in the Cretaceous from nowhere," explains lead author Qiang Fu, Associate Research Professor at the Nanjing Institute of Geology and Paleontology, China. "Studying fossil flowers, especially those from earlier geologic periods, is the only reliable way to get an answer to these questions."
Before now, angiosperms (flowering plants) were thought to have a history of no more than 130 million years. The discovery of the novel flower species, which the study authors named Nanjinganthus dendrostyla, throws widely accepted theories of plant evolution into question, by suggesting that they existed around 50 million years earlier. Nanjinganthus also has a variety of 'unexpected' characteristics according to almost all of these theories.
Angiosperms are an important member of the plant kingdom, and their origin has been the topic of long-standing debate among evolutionary biologists. Many previously thought angiosperms could be no more than 130 million years old. However, molecular clocks have indicated that they must be older than this. Until now, there has been no convincing fossil-based evidence to prove that they existed further back in time.
"Researchers were not certain where and how flowers came into existence because it seems that many flowers just popped up in the Cretaceous from nowhere," explains lead author Qiang Fu, Associate Research Professor at the Nanjing Institute of Geology and Paleontology, China. "Studying fossil flowers, especially those from earlier geologic periods, is the only reliable way to get an answer to these questions."
December 11, 2018
NASA's Newly Arrived OSIRIS-REx Spacecraft Already Discovers Water on Asteroid
Source: nasa.gov
Recently analyzed data from NASA’s Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer (OSIRIS-REx) mission has revealed water locked inside the clays that make up its scientific target, the asteroid Bennu.
During the mission’s approach phase, between mid-August and early December, the spacecraft traveled 1.4 million miles (2.2 million km) on its journey from Earth to arrive at a location 12 miles (19 km) from Bennu on Dec. 3. During this time, the science team on Earth aimed three of the spacecraft’s instruments towards Bennu and began making the mission’s first scientific observations of the asteroid. OSIRIS-REx is NASA’s first asteroid sample return mission.
Data obtained from the spacecraft’s two spectrometers, the OSIRIS-REx Visible and Infrared Spectrometer (OVIRS) and the OSIRIS-REx Thermal Emission Spectrometer (OTES), reveal the presence of molecules that contain oxygen and hydrogen atoms bonded together, known as “hydroxyls.” The team suspects that these hydroxyl groups exist globally across the asteroid in water-bearing clay minerals, meaning that at some point, Bennu’s rocky material interacted with water. While Bennu itself is too small to have ever hosted liquid water, the finding does indicate that liquid water was present at some time on Bennu’s parent body, a much larger asteroid.
“The presence of hydrated minerals across the asteroid confirms that Bennu, a remnant from early in the formation of the solar system, is an excellent specimen for the OSIRIS-REx mission to study the composition of primitive volatiles and organics,” said Amy Simon, OVIRS deputy instrument scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “When samples of this material are returned by the mission to Earth in 2023, scientists will receive a treasure trove of new information about the history and evolution of our solar system.”
Read more: https://www.nasa.gov/press-release/nasa-s-newly-arrived-osiris-rex-spacecraft-already-discovers-water-on-asteroid
December 9, 2018
50,000 year old tiara made of woolly mammoth ivory found in world famous Denisova Cave
https://siberiantimes.com/science/casestudy/news/50000-year-old-tiara-made-of-woolly-mammoth-ivory-found-in-world-famous-denisova-cave/The remarkable find was made this summer in the famous Siberian cave where over many millennia early Home sapiens lived alongside extinct Neanderthals and another long-gone branch of ancient man known as Denisovans.
The suspicion is that the tiara - or diadem - was made by Denisovans who are already known to have had the technology 50,000 or so years ago to make elegant needles out of ivory and a sophisticated and beautiful stone bracelet.
The tiara maybe the oldest of its type in the world.
It appears to have had a practical use: to keep hair out of the eyes; it’s size indicates it was for male, not female, use.
Another theory, although related to tiaras made 20,000 years later by people living around river Yana in Yakutia is that they could have denoted the family or tribe of ancient man, acting like a passport or identity card.
The suspicion is that the tiara - or diadem - was made by Denisovans who are already known to have had the technology 50,000 or so years ago to make elegant needles out of ivory and a sophisticated and beautiful stone bracelet.
The tiara maybe the oldest of its type in the world.
It appears to have had a practical use: to keep hair out of the eyes; it’s size indicates it was for male, not female, use.
Another theory, although related to tiaras made 20,000 years later by people living around river Yana in Yakutia is that they could have denoted the family or tribe of ancient man, acting like a passport or identity card.
November 30, 2018
Extinct 'Denisovan' people may have lived on Earth's highest plateau
https://www.newscientist.com/article/2186984-extinct-denisovan-people-may-have-lived-on-earths-highest-plateau/Humans arrived on the Tibetan Plateau tens of thousands of years earlier than we thought. This raises the possibility that the first humans to cope with the harsh conditions there were not modern humans, but the ancient Denisovans.
The Tibetan Plateau is a tough environment. The average annual temperature is close to 0 °C, and on average it’s 4000 metres above sea level so the air is difficult to breathe. Most researchers assumed that humans didn’t move onto the Tibetan Plateau until just 12,000 years ago – and only occupied it permanently about 3600 years ago.
An archaeological site called Nwya Devu suggests otherwise. The site, which is on the Tibetan Plateau 4600 metres above sea level, has yielded thousands of stone tools, albeit few organic remains.
By using technology that establishes how many years have passed since the soil burying the tools was last exposed, archaeologists estimate that the oldest tools are between 40,000 and 30,000 years old. That means humans first occupied the Tibetan Plateau much earlier than we thought.
The Tibetan Plateau is a tough environment. The average annual temperature is close to 0 °C, and on average it’s 4000 metres above sea level so the air is difficult to breathe. Most researchers assumed that humans didn’t move onto the Tibetan Plateau until just 12,000 years ago – and only occupied it permanently about 3600 years ago.
An archaeological site called Nwya Devu suggests otherwise. The site, which is on the Tibetan Plateau 4600 metres above sea level, has yielded thousands of stone tools, albeit few organic remains.
By using technology that establishes how many years have passed since the soil burying the tools was last exposed, archaeologists estimate that the oldest tools are between 40,000 and 30,000 years old. That means humans first occupied the Tibetan Plateau much earlier than we thought.
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