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Categories: Geoscience: Earth Science, Paleontology: Fossils
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 New tusk-analysis techniques reveal surging testosterone in male woolly mammoths
(via sciencedaily.com) Original source Traces of sex hormones extracted from a woolly mammoth's tusk provide the first direct evidence that adult males experienced musth, a testosterone-driven episode of heightened aggression against rival males, according to a new study.
Published Indo-Pacific corals more resilient to climate change than Atlantic corals
(via sciencedaily.com) Original source In the face of global warming and other environmental changes, corals in the Atlantic Ocean have declined precipitously in recent years, while corals in the Pacific and Indian Oceans are faring better. By describing several species of symbiotic algae that these corals need to grow, an international team has found that these mutualistic relationships from the Indo-Pacific may be more flexible and ultimately resilient to higher ocean temperatures than those in the Atlantic.
Published 'Golden' fossils reveal origins of exceptional preservation
(via sciencedaily.com) Original source A recent study found that many of the fossils from Germany's Posidonia shale do not get their gleam from pyrite, commonly known as fool's gold, which was long thought to be the source of the shine. Instead, the golden hue is from a mix of minerals that hints at the conditions in which the fossils formed. The discovery is important for understanding how the fossils -- which are among the world's best-preserved specimens of sea life from the Early Jurassic -- came to form in the first place, and the role that oxygen in the environment had in their formation.
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 Fossil find in California shakes up the natural history of cycad plants
(via sciencedaily.com) Original source According to researchers, a new analysis of an 80-million-year-old permineralized pollen cone found in the Campanian Holz Shale formation located in Silverado Canyon, California, offers a more accurate cycad natural history -- one where the plants diversified during the Cretaceous.
Published Researchers discover that the ice cap is teeming with microorganisms
(via sciencedaily.com) Original source Greenlandic ice is teeming with life, both on the surface and underneath. There are microscopic organisms that until recently science had no idea existed. There is even evidence to suggest that the tiny creatures color the ice and make it melt faster.
Published West Antarctic Ice Sheet retreated far inland, re-advanced since last Ice Age
(via sciencedaily.com) Original source The West Antarctic Ice Sheet is melting rapidly, raising concerns it could cross a tipping point of irreversible retreat in the next few decades if global temperatures rise 1.5 to 2.0 degrees Celsius (2.7 to 3.8 degrees Fahrenheit) above preindustrial levels. New research finds that 6,000 years ago, the grounded edge of the ice sheet may have been as far as 250 kilometers (160 miles) inland from its current location, suggesting the ice retreated deep into the continent after the end of the last ice age and re-advanced before modern retreat began.
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 Ecosystem evolution in Africa
(via sciencedaily.com) Original source New research pushes back the oldest evidence of C4 grass-dominated habitats in Africa -- and globally -- by more than 10 million years, with important implications for primate evolution and the origins of tropical C4 grasslands and savanna ecosystems across the African continent and around the world.
Published The future is foggy for Arctic shipping
(via sciencedaily.com) Original source As the Arctic warms and loses sea ice, trans-Arctic shipping has increased, reducing travel time and costs for international trade. However, a new study finds that the Arctic Ocean is getting foggier as ice disappears, reducing visibility and causing costly delays as ships slow to avoid hitting dangerous sea ice.
Published Is the ocean a solution for ushering in the era of environmentally friendly energy?
(via sciencedaily.com) Original source Researchers confirm the superiority of seawater batteries that use chelating agents.
Published Twilight zone at risk from climate change
(via sciencedaily.com) Original source Life in the ocean's 'twilight zone' could decline dramatically due to climate change, new research suggests.
Published Ocean ecosystem: Mixotrophic microorganisms play key role
(via sciencedaily.com) Original source Researchers have identified a previously unknown group of bacteria, called UBA868, as key players in the energy cycle of the deep ocean. They are significantly involved in the biogeochemical cycle in the marine layer between 200 and 1000 meters.
Published Searching for ancient bears in an Alaskan cave led to an important human discovery
(via sciencedaily.com) Original source Genetic analysis links 3,000-year-old bone found in cave to modern Alaska Natives.
Published Massive iceberg discharges during the last ice age had no impact on nearby Greenland, raising new questions about climate dynamics
(via sciencedaily.com) Original source New findings suggest that Heinrich Events had no discernible impact on temperatures in Greenland, which could have repercussions for scientists' understanding of past climate dynamics.
Published A more precise model of the Earth's ionosphere
(via sciencedaily.com) Original source The ionosphere -- the region of geospace spanning from 60 to 1000 kilometers above the Earth -- impairs the propagation of radio signals from global navigation satellite systems (GNSS) with its electrically charged particles. This is a problem for the ever higher precision required by these systems -- both in research and for applications such as autonomous driving or precise orbit determination of satellites. Models of the ionosphere and its uneven, dynamic charge distribution can help correct the signals for ionospheric delays, which are one of the main error sources in GNSS applications. Researchers have presented a new model of the ionosphere, developed on the basis of neural networks and satellite measurement data from 19 years. In particular, it can reconstruct the topside ionosphere, the upper, electron-rich part of the ionosphere much more precisely than before. It is thus also an important basis for progress in ionospheric research, with applications in studies on the propagation of electromagnetic waves or for the analysis of certain space weather events, for example.
Published Algae in Swedish lakes provide insights to how complex life on Earth developed
(via sciencedaily.com) Original source By studying green algae in Swedish lakes, a research team has succeeded in identifying which environmental conditions promote multicellularity. The results give us new clues to the amazing paths of evolution.
Published Colorado's spicy ancient history of chili peppers
(via sciencedaily.com) Original source Recently identified chili pepper fossils from Boulder and Denver museums challenge millions of years of global tomato evolutionary history. Now, that's some spicy science!
Published 360-million-year-old Irish fossil provides oldest evidence of plant self-defense in wood
(via sciencedaily.com) Original source Scientists have discovered the oldest evidence of plant self-defense in wood in a 360-million-year-old fossil from south-eastern Ireland. Plants can protect their wood from infection and water loss by forming special structures called 'tyloses'. These prevent bacterial and fungal pathogens from getting into the heartwood of living trees and damaging it. However, it was not previously known how early in the evolution of plants woody species became capable of forming such defenses. Published today in Nature Plants is the oldest evidence of tylosis formation from Late Devonian (360-million-year-old) fossil wood from the Hook Head Peninsula area, Co. Wexford, Ireland.