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Categories: Ecology: Invasive Species, Offbeat: Space

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The earliest galaxies are thought to have formed as the gravitational pull of dark matter, which has been impossible to study directly, slowly drew in enough hydrogen and helium to ignite stars. But astrophysicists now show that after the Big Bang, hydrogen and helium gas bounced at supersonic speeds off dense, slowly moving clumps of cold dark matter. When the gas fell back in millennia later, stars formed all at once, creating small, exceptionally bright galaxies. If models of cold dark matter are correct, the James Webb Space Telescope should be able to find patches of bright galaxies in the early universe, potentially offering the first effective test for theories about dark matter. If it doesn't, scientists have to go back to the drawing board with dark matter.

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Green roofs have become increasingly popular thanks to their benefits related to climate adaptation, mitigation, and urban biodiversity management. But, in the U.S., green roofs are typically planted with non-native plants in sterile soils, and their effectiveness declines over time. A new study finds that managing green roof soil microbes boosts healthy urban soil development, which is a methodology that could be applied to support climate resilience in cities.

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As sea otters recolonize a California estuary, they are restoring its degraded geology by keeping populations of overgrazing marsh crabs in check, a new study shows. The crabs' appetite for plant roots, and their tunneling behavior had caused many of the estuary's marshes and creekbanks to erode and collapse in the otters' absence. Today, erosion has slowed by up to 90% in areas with large otter populations and marshes and streambeds are restabilizing.

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How is a beech leaf constructed? What determines the appearance of an asparagus? A new 'encyclopaedia' helps us learn more about the building blocks of plants. The encyclopaedia, probably the largest of its kind, could be used to improve targeted plant breeding efforts, to make them both more climate-resilient and more easily digestible.

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The James Webb Space Telescope observed 19 nearby face-on spiral galaxies in near- and mid-infrared light as part of its contributions to the Physics at High Angular resolution in Nearby GalaxieS (PHANGS) program.

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The next generation of advanced telescopes could sharpen the hunt for potential extraterrestrial life by closely scrutinizing the atmospheres of nearby exoplanets, new research suggests.

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Plant biologists report that a species of tree fern found only in Panama reanimates its own dead leaf fronds, converting them into root structures that feed the mother plant. The fern, Cyathea rojasiana, reconfigures these 'zombie leaves,' reversing the flow of water to draw nutrients back into the plant.

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Scientists have identified 18 new tidal disruption events (TDEs) -- extreme instances when a nearby star is tidally drawn into a black hole and ripped to shreds. The detections more than double the number of known TDEs in the nearby universe.

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Ground-penetrating radar on board NASA's Mars Perseverance rover has confirmed that the Jezero Crater, formed by an ancient meteor impact just north of the Martian equator, once harbored a vast lake and river delta. Over eons, sediment deposition and erosion within the crater shaped the geologic formations visible on the surface today. The discovery of lake sediments reinforces the hope that traces of life might be found in soil and rock samples collected by Perseverance.

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Physicists discovered stars near the edge of the Milky Way travel more slowly than those closer to its center -- a surprise suggesting our galaxy's gravitational core may have less dark matter than previously thought.

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'Hidden' stars including a new type of elderly giant nicknamed an 'old smoker' have been spotted for the first time by astronomers. The mystery objects exist at the heart of our Milky Way galaxy and can sit quietly for decades -- fading almost to invisibility -- before suddenly puffing out clouds of smoke, according to a new study.

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The spread of West Nile virus in Europe is strongly linked to agricultural activities, urbanization, and bird migration, according to new research.

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Data gathered through years of observation reveal an innocuous-seeming ant is disrupting an ecosystem in East Africa, illustrating the complex web of interactions among ants, trees, lions, zebras and buffaloes.

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European forests with a greater diversity of tree species are more resilient to storms, according to new research.

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How does loss of habitat affect the animals still living there? A genetic study of saltwater-adapted Savannah sparrows around the San Francisco Bay Area shows that the 90% loss of tidal marsh habitat has led to more interbreeding with freshwater-adapted Savannah sparrows, diminishing their genetic adaptation to saltwater, such as enlarged kidneys and larger beak. This could lessen their ability to live in a saltwater habitat.

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The brown bear is one of the largest living terrestrial carnivores, and is widely distributed across the Northern Hemisphere. Unlike many other large carnivores that went extinct at the end of the last Ice Age (cave bear, sabretoothed cats, cave hyena), the brown bear is one of the lucky survivors that made it through to the present. The question has puzzled biologists for close to a century -- how was this so?

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New research shows that atmospheric pressure fluctuations that pull gases up from underground could be responsible for releasing subsurface methane into Mars' atmosphere; knowing when and where to look for methane can help the Curiosity rover search for signs of life.

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Ecologists have long known that standing dead trees, commonly referred to as snags, are an important habitat element for forest dwellers and act as a driver of biodiversity. They're so important that in some managed forests, snag creation is part of the conservation tool kit -- i.e., crews sometimes convert a percentage of live trees into dead ones through techniques ranging from sawing off their tops to wounding their trunks to injecting them with disease-causing fungi.

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New worldwide maps of temperatures inside tropical forests show that global warming affect different way in different parts of the forests. Undergrowth level temperature of the tropical forests can be even 4 degrees less than average temperature of the area.

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An international team of astronomers have found a new and unknown object in the Milky Way that is heavier than the heaviest neutron stars known and yet simultaneously lighter than the lightest black holes known.