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RandiFan1290

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Member since: Tue Jul 15, 2003, 03:58 PM
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Fossils suggest flowers originated 50 million years earlier than thought

https://www.sciencedaily.com/releases/2018/12/181218115205.htm


Scientists 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."

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

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.

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.
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