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Categories: Ecology: Extinction, Space: Structures and Features

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Scientists have detected the highest energy gamma rays ever from a dead star called a pulsar. The energy of these gamma rays clocked in at 20 tera-electronvolts, or about ten trillion times the energy of visible light. This observation is hard to reconcile with the theory of the production of such pulsed gamma rays, as the international team reports.

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A pair of theoretical physicists are reporting that the same observations inspiring the hunt for a ninth planet might instead be evidence within the solar system of a modified law of gravity originally developed to understand the rotation of galaxies.

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Mammals living in South Africa's Greater Kruger National Park, home to one of the world's largest remaining lion populations, are far more afraid of hearing human voices than lion vocalizations or hunting sounds such as dogs barking or gunshots.

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For decades, scientists have assumed that mammals and their relatives that survived challenging times (like those during mass extinctions) made it because they were generalists that were able to eat just about anything and adapt to whatever life threw at them. A new study into the mammal family tree through multiple mass extinctions revealed that the species that survived aren't as generic as scientists had thought: instead, having new and different traits can be the key to succeeding in the aftermath of a catastrophe.

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Despite decades of decline, a genetic analysis of ruffed grouse reveals that Pennsylvania's state bird harbors more genetic diversity and connectivity than expected. The findings suggest that the iconic game bird could be maintained in persistent numbers if appropriate protections are implemented.

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In the James Webb Space Telescope’s (JWST) first images of the universe’s earliest galaxies, the young galaxies appear too bright, too massive and too mature to have formed so soon after the Big Bang. Using new simulations, a team of astrophysicists now has discovered that these galaxies likely are not so massive after all. Although a galaxy’s brightness is typically determined by its mass, the new findings suggest that less massive galaxies can glow just as brightly from irregular, brilliant bursts of star formation.

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Commercial whaling in the 20th century decimated populations of large whales but also appears to have had a lasting impact on the genetic diversity of today’s surviving whales, new research shows.

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A recent study sheds new light on the elusive Roosmalens' dwarf porcupine, a poorly understood neotropical species. After 22 years of relative obscurity, this research uncovers vital information about its distribution, phylogenetics, and potential conservation threats, not only revealing its endemic presence in the Madeira biogeographical province but also expanding its known range in the southern Amazon.

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In recent years, astronomy has seen itself in a bit of crisis: Although we know that the Universe expands, and although we know approximately how fast, the two primary ways to measure this expansion do not agree. Now astrophysicists suggest a novel method which may help resolve this tension.

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Using an innovative new approach to sampling corals, researchers are now able to create maps of coral biochemistry that reveal with unprecedented detail the distribution of compounds that are integral to the healthy functioning of reefs.

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For decades, fish-eating killer whales in the Pacific Northwest have been observed harassing and even killing porpoises without consuming them —- a perplexing behavior that has long intrigued scientists.

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Researchers tried a new approach to resolve the scientific debate over whether it was a giant asteroid or volcanoes that wiped out the dinosaurs -- they removed scientists from the debate and let the computers decide. The researchers created a model powered by 130 interconnected processors that, without human input, reverse-engineered the Cretaceous-Paleogene mass extinction until they reached a scenario that matched the fossil record. The model determined that while a meteorite contributed to the cataclysm, the outpouring of climate-altering gases from the nearly 1-million-year eruptions of volcanoes in western India's Deccan Traps would have been sufficient to trigger the extinction and clear the way for the ascendance of mammals.

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Past cycles of climate change, along with human exploitation, have led to only small and isolated stocks of Atlantic walrus remaining. The current population is at high risk of the same issues affecting them severely, according to a new study.

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Researchers studying arboreal ants in a Florida forest explore the fundamental question of how resource availability and competition shape biodiversity.

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A newly discovered nearby supernova whose star ejected up to a full solar mass of material in the year prior to its explosion is challenging the standard theory of stellar evolution. The new observations are giving astronomers new insight into what happens in the final year prior to a star's death and explosion.

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Combinations of unfavorable weather conditions over several years can cause a decline in insect biomass.

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The supermassive black hole at the heart of galaxy M87, made famous by the first picture of a black hole shadow, has yielded another first: the jet shooting out from the black hole has been confirmed to wobble, providing direct proof that the black hole is spinning.

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Protecting large swaths of Earth's land can help stem the tide of biodiversity loss -- especially when those protected areas are in less disturbed landscapes and in countries with effective national governance. A new study looked at how amphibians, reptiles, mammals and birds fared in protected versus unprotected areas worldwide. Vertebrate abundance decreased five times more slowly inside protected areas, offering much-needed support for the United Nations' '30 by 30' conservation initiative.

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How are environmental changes, loss of biodiversity, and the spread of pathogens connected? The answer is a puzzle. Researchers have now described one piece of that puzzle, showing that the destruction of tropical rainforests harms the diversity of mosquito species. At the same time, more resilient species of mosquitoes become more prevalent -- which also means the viruses they carry are more abundant. If there are many individuals of a given species, those viruses can spread quickly.

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In a new study, scientists have shown that sweeping molten oceans have a large influence on the observed properties of hot rocky Super-Earths, such as their size and evolutionary path.