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Categories: Anthropology: General, Space: The Solar System
Published Evidence of Ice Age human migrations from China to the Americas and Japan
(via sciencedaily.com) Original source Scientists have used mitochondrial DNA to trace a female lineage from northern coastal China to the Americas. By integrating contemporary and ancient mitochondrial DNA, the team found evidence of at least two migrations: one during the last ice age, and one during the subsequent melting period. Around the same time as the second migration, another branch of the same lineage migrated to Japan, which could explain Paleolithic archeological similarities between the Americas, China, and Japan.
Published Webb looks for Fomalhaut's asteroid belt and finds much more
(via sciencedaily.com) Original source Astronomers used NASA's James Webb Space Telescope to image the warm dust around a nearby young star, Fomalhaut, in order to study the first asteroid belt ever seen outside of our solar system in infrared light. But to their surprise, the dusty structures are much more complex than the asteroid and Kuiper dust belts of our solar system. Overall, there are three nested belts extending out to 14 billion miles (23 billion kilometers) from the star; that's 150 times the distance of Earth from the Sun. The scale of the outermost belt is roughly twice the scale of our solar system's Kuiper Belt of small bodies and cold dust beyond Neptune. The inner belts -- which had never been seen before -- were revealed by Webb for the first time.
Published Nose shape gene inherited from Neanderthals
(via sciencedaily.com) Original source Humans inherited genetic material from Neanderthals that affects the shape of our noses, finds a new study.
Published Archaeologists map hidden NT landscape where first Australians lived more than 60,000 years ago
(via sciencedaily.com) Original source Scientists have used sub-surface imaging and aerial surveys to see through floodplains in the Red Lily Lagoon area of West Arnhem Land in Australia. These ground-breaking methods showed how this important landscape in the Northern Territory was altered as sea levels rose about 8,000 years ago.
Published Hubble follows shadow play around planet-forming disk
(via sciencedaily.com) Original source The young star TW Hydrae is playing 'shadow puppets' with scientists observing it with NASA's Hubble Space Telescope. In 2017, astronomers reported discovering a shadow sweeping across the face of a vast pancake-shaped gas-and-dust disk surrounding the red dwarf star. The shadow isn't from a planet, but from an inner disk slightly inclined relative to the much larger outer disk -- causing it to cast a shadow. One explanation is that an unseen planet's gravity is pulling dust and gas into the planet's inclined orbit. The young star TW Hydrae is playing 'shadow puppets' with scientists observing it with NASA's Hubble Space Telescope. Now, a second shadow -- playing a game of peek-a-boo -- has emerged in just a few years between observations stored in Hubble's MAST archive. This could be from yet another disk nestled inside the system. The two disks are likely evidence of a pair of planets under construction.
Published Research reveals longstanding cultural continuity at oldest occupied site in West Africa
(via sciencedaily.com) Original source Stone tools recovered from near the Senegalese coast extend occupation of the region back to 150 thousand years ago and are comparable to those seen across Africa at this time, but uniquely persist in the region until 10 thousand years ago.
Published Do your homework to prep for the 2023 and 2024 eclipses
(via sciencedaily.com) Original source This year and next, Americans will have the extraordinary opportunity to witness two solar eclipses as both will be visible throughout the continental U.S. Both occurrences promise to be remarkable events and teachable moments but preparation is essential. Astronomers provide a practical playbook to help teachers, students, and the general public prepare for the eclipse events.
Published Astronomers spot a star swallowing a planet
(via sciencedaily.com) Original source Scientists have observed a star swallowing a planet for the first time. Earth will meet a similar fate in 5 billion years.
Published Scientists recover an ancient woman's DNA from a 20,000-year-old pendant
(via sciencedaily.com) Original source An international research team has for the first time successfully isolated ancient human DNA from a Paleolithic artefact: a pierced deer tooth discovered in Denisova Cave in southern Siberia. To preserve the integrity of the artefact, they developed a new, nondestructive method for isolating DNA from ancient bones and teeth. From the DNA retrieved they were able to reconstruct a precise genetic profile of the woman who used or wore the pendant, as well as of the deer from which the tooth was taken. Genetic dates obtained for the DNA from both the woman and the deer show that the pendant was made between 19,000 and 25,000 years ago. The tooth remains fully intact after analysis, providing testimony to a new era in ancient DNA research, in which it may become possible to directly identify the users of ornaments and tools produced in the deep past.
Published What would the Earth look like to an alien civilization located light years away?
(via sciencedaily.com) Original source What would the Earth look like to an alien civilization located light years away? A team of researchers has used crowd-sourced data to simulate radio leakage from mobile towers and predict what an alien civilization might detect from various nearby stars, including Barnard's star, six light years away from Earth.
Published Scientists present evidence for a billion-years arms race between viruses and their hosts
(via sciencedaily.com) Original source Researchers have proposed a new evolutionary model for the origin of a kingdom of viruses called Bamfordvirae, suggesting a billion-years evolutionary arms race between two groups within this kingdom and their hosts.
Published A stormy, active sun may have kickstarted life on Earth
(via sciencedaily.com) Original source The first building blocks of life on Earth may have formed thanks to eruptions from our Sun, a new study finds. A series of chemical experiments show how solar particles, colliding with gases in Earth's early atmosphere, can form amino acids and carboxylic acids, the basic building blocks of proteins and organic life.
Published New research redefines mammalian tree of life
(via sciencedaily.com) Original source Scientists from around the globe are using the largest mammalian genomic dataset in history to determine the evolutionary history of the human genome in the context of mammalian evolutionary history. Their ultimate goal is to better identify the genetic basis for traits and diseases in people and other species.
Published Superflare with massive, high-velocity prominence eruption
(via sciencedaily.com) Original source A team of Japanese astronomers used simultaneous ground-based and space-based observations to capture a more complete picture of a superflare on a star. The observed flare started with a very massive, high-velocity prominence eruption. These results give us a better idea of how superflares and stellar prominence eruptions occur.
Published Information 'deleted' from the human genome may be what made us human
(via sciencedaily.com) Original source What the human genome is lacking compared with the genomes of other primates might have been as crucial to the development of humankind as what has been added during our evolutionary history, according to a new study led by researchers at Yale and the Broad Institute of MIT and Harvard. The new findings, published April 28 in the journal Science, fill an important gap in what is known about historical changes to the human genome.
Published Elephant ecosystems in decline
(via sciencedaily.com) Original source Global space for Asian elephant habitats has been in rapid decline since the 1700s, a new report reveals. More than 3 million square kilometers of the Asian elephant's historic habitat range has been lost in just three centuries and may underlie present-day conflicts between elephants and people.
Published Prolonged droughts likely spelled the end for Indus megacities
(via sciencedaily.com) Original source New research has found evidence -- locked into an ancient stalagmite from a cave in the Himalayas -- of a series of severe and lengthy droughts which may have upturned the Bronze Age Indus Civilization.
Published New findings indicate gene-edited rice might survive in Martian soil
(via sciencedaily.com) Original source New research suggests future Martian botanists may be able to grow gene-edited rice on Mars.
Published Brain circuits for locomotion evolved long before appendages and skeletons
(via sciencedaily.com) Original source Scientists found parallels between the neural circuitry that guides locomotion in sea slugs and in more complex animals like mammals.
Published Asteroid's comet-like tail Is not made of dust, solar observatories reveal
(via sciencedaily.com) Original source We have known for a while that asteroid 3200 Phaethon acts like a comet. It brightens and forms a tail when it's near the Sun, and it is the source of the annual Geminid meteor shower, even though comets are responsible for most meteor showers. Scientists had blamed Phaethon's comet-like behavior on dust escaping from the asteroid as it's scorched by the Sun. However, a new study using two NASA solar observatories reveals that Phaethon's tail is not dusty at all but is actually made of sodium gas.