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Categories: Anthropology: Cultures, Geoscience: Geology
Published The encounter between Neanderthals and Sapiens as told by their genomes
(via sciencedaily.com) Original source About 40,000 years ago, Neanderthals, who had lived for hundreds of thousands of years in the western part of the Eurasian continent, gave way to Homo sapiens, who had arrived from Africa. This replacement was not sudden, and the two species coexisted for a few millennia, resulting in the integration of Neanderthal DNA into the genome of Sapiens. Researchers have analyzed the distribution of the portion of DNA inherited from Neanderthals in the genomes of humans (Homo sapiens) over the last 40,000 years. These statistical analyses revealed subtle variations in time and geographical space.
Published Ice sheet surface melt is accelerating in Greenland and slowing in Antarctica
(via sciencedaily.com) Original source Surface ice in Greenland has been melting at an increasing rate in recent decades, while the trend in Antarctica has moved in the opposite direction, according to researchers.
Published A non-exploitative economy favored the splendor of the Iberian Peninsula's Copper Age communities
(via sciencedaily.com) Original source A study describes the productive forces of the Chalcolithic communities of the southern half of the Iberian Peninsula as being very diverse, both in the type of tasks performed and in intensity, with a high degree of cooperation and no apparent signs of dependence between the different types of settlements or of political centralization. The work, based on the analysis of macrolithic tool data and the additional support of bioarchaeological information, allows to confirm the large ditched enclosure of Valencina de la Concepción (Seville) as a macro-populated area, inhabited by thousands of people, and not only as a place of worship.
Published Plate tectonic surprise: Geologist unexpectedly finds remnants of a lost mega-plate
(via sciencedaily.com) Original source Geologists have reconstructed a massive and previously unknown tectonic plate that was once one-quarter the size of the Pacific Ocean. The team had predicted its existence over 10 years ago based on fragments of old tectonic plates found deep in the Earth’s mantle. To the lead researchers surprise, she found that oceanic remnants on northern Borneo must have belonged to the long-suspected plate, which scientists have named Pontus. She has now reconstructed the entire plate in its full glory.
Published Climate change brings earlier arrival of intense hurricanes
(via sciencedaily.com) Original source New research has revealed that since the 1980s, Category 4 and 5 hurricanes (maximum wind speed greater than 131 miles per hour) have been arriving three to four days earlier with each passing decade of climate change.
Published Ancient carbon in rocks releases as much carbon dioxide as the world's volcanoes
(via sciencedaily.com) Original source New research has overturned the traditional view that natural rock weathering acts as a carbon sink that removes CO2 from the atmosphere. Instead, this can also act as a large CO2 source, rivaling that of volcanoes.
Published Volcanic ash effects on Earth systems
(via sciencedaily.com) Original source To bridge the knowledge gap between volcanologists and atmospheric scientists working on climate change and observing global systems, researchers have characterized volcanic ash samples from many explosive eruptions of a broad compositional range.
Published Discovery of massive undersea water reservoir could explain New Zealand's mysterious slow earthquakes
(via sciencedaily.com) Original source Researchers working to image New Zealand's Hikurangi earthquake fault have uncovered a sea's worth of water buried in the Earth's crust. The water was carried down by eroding volcanic rocks and is believed to be dampening the earthquake fault, allowing it to release most of the pent-up tectonic stress through harmless slow slip earthquakes.
Published Ancient plant wax reveals how global warming affects methane in Arctic lakes
(via sciencedaily.com) Original source In a new study, researchers examined the waxy coatings of leaves preserved as organic molecules within sediment from the early-to-middle Holocene, a period of intense warming that occurred due to slow changes in Earth's orbit 11,700 to 4,200 years ago. They found that warming potentially could lead to a previously under-appreciated flux in methane emissions from lakes.
Published Exploring the effect of water on seismic wave attenuation in the upper mantle
(via sciencedaily.com) Original source The mechanism facilitating the smooth movement of the oceanic lithosphere over the underlying asthenosphere (upper mantle) remains poorly understood. Recently, researchers from Japan investigated the effect of water on the seismic properties of olivine rocks, finding that water retention in the asthenosphere can induce sharp drops in shear wave velocity. This also explained other seismic changes observed at the lithosphere-asthenosphere boundary. These findings provide invaluable insights into the diverse seismic activities on Earth.
Published New research reveals extreme heat likely to wipe out humans and mammals in the distant future
(via sciencedaily.com) Original source A new study shows unprecedented heat is likely to lead to the next mass extinction, akin to when the dinosaurs died out, eliminating nearly all mammals in some 250 million years time.
Published Pollen analysis suggests peopling of Siberia and Europe by modern humans occurred during a major Pleistocene warming spell
(via sciencedaily.com) Original source A new study appearing in Science Advances compares Pleistocene vegetation communities around Lake Baikal in Siberia, Russia, to the oldest archeological traces of Homo sapiens in the region. The researchers use the 'remarkable evidence' to tell a compelling story from 45,000-50,000 years ago with new detail: how the first humans migrated across Europe and Asia.
Published Ancient Amazonians intentionally created fertile 'dark earth'
(via sciencedaily.com) Original source A new study suggests patches of fertile soil in the Amazon, known as dark earth, were intentionally produced by ancient Amazonians as a way to improve the soil and sustain large and complex societies.
Published Archaeologists discover world's oldest wooden structure
(via sciencedaily.com) Original source Half a million years ago, earlier than was previously thought possible, humans were building structures made of wood, according to new research.
Published A newly identified virus emerges from the deep
(via sciencedaily.com) Original source Marine virologists analyzed sediment from the Mariana Trench, the deepest place on Earth, and identified a new bacteriophage.
Published Crucial third clue to finding new diamond deposits
(via sciencedaily.com) Researchers studying diamond-rich rocks from Western Australia's Argyle volcano have identified the missing third key ingredient needed to bring valuable pink diamonds to the Earth's surface where they can be mined, which could greatly help in the global hunt for new deposits.
Published How just one set of animal tracks can provide a wealth of information
(via sciencedaily.com) Original source Rock faces in Namibia are decorated with hundreds of stone-age images not only of animals and human footprints, but also of animal tracks. These have been largely neglected to date as researchers lacked the knowledge required to interpret them. Archaeologists have now worked together with animal tracking experts to investigate the engraved animal tracks on six rock faces in more detail, and were able to determine detailed information on the species, age, sex, limbs, side of the body, trackway and relative direction of the tracks.
Published Earth's stability and ability to support civilization at risk: Six of nine planetary boundaries exceeded
(via sciencedaily.com) Original source A new study updates the planetary boundary framework and shows human activities are increasingly impacting the planet and, thereby, increasing the risk of triggering dramatic changes in overall Earth conditions.
Published Scientific ocean drilling discovers dynamic carbon cycling in the ultra-deep-water Japan Trench
(via sciencedaily.com) Original source Hadal trenches, with their deepest locations situated in the so-called hadal zone, the deepest parts of the ocean in water depth >6km, are the least-explored environment on Earth, linking the Earth's surface and its deeper interior. An international team conducting deep-subsurface sampling in a hadal trench at high spatial resolution has revealed exciting insights on the carbon cycling in the trench sediment.
Published St Helena's 'liberated' Africans came from West Central Africa between northern Angola and Gabon
(via sciencedaily.com) Original source Between 1840 and 1867, thousands of enslaved Africans who had been 'liberated' from slave ships intercepted by the British Royal Navy were taken to the South Atlantic island of St Helena. But little is written in history books or otherwise known about the lives of these individuals. Now, ancient DNA analyses offer the first direct evidence for the origins of St Helena's liberated Africans.