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Categories: Geoscience: Geology, Paleontology: Early Mammals and Birds

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A tiny fossil penguin plays a huge role in the evolutionary history of the bird, an international study shows.

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Scientists have detected geochemical signatures of magma pooling and melting beneath the subsurface during the 'Fagradalsfjall Fires', that began on Iceland's Reykjanes peninsula in 2021. Samples show that the start of the eruption began with massive pooling of magma, contrasting initial hypothesis for magma ascent straight from the mantle.

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Sapphires are among the most precious gems, yet they consist solely of chemically 'contaminated' aluminum oxide, or corundum. It is widely assumed that these crystals with their characteristically blue color come from deep crustal rocks and accidentally ended up on the Earth's surface as magma ascended. Geoscientists have now been able to show that the sapphire grains found in the Eifel (Germany) formed in association with volcanism.

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Birds tend to be more colorful in the tropics, and scientists wanted to find out how they got there: if colorful feathers evolved in the tropics, or if tropical birds have brightly-colored ancestors that came to the region from somwhere else. Scientists built a database of 9,409 birds to explore the spread of color across the globe. They found that iridescent, colorful feathers originated 415 times across the bird tree of life, and in most cases, arose outside of the tropics -- and that the ancestor of all modern birds likely had iridescent feathers, too.

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A new analysis of rocks thought to be at least 2.5 billion years old helps clarify the chemical history of Earth's mantle -- the geologic layer beneath the planet's crust. The findings hone scientists' understanding of Earth's earliest geologic processes, and they provide new evidence in a decades-long scientific debate about the geologic history of Earth. Specifically, the results provide evidence that the oxidation state of the vast majority of Earth's mantle has remained stable through geologic time and has not undergone major transitions, contrary to what has been suggested previously by other researchers.

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Fluids circulating underground change rocks over the course of time. These processes must be taken into account if they are to be used as a climate archive. Researchers have used 380-million-year-old limestones from Hagen-Hohenlimburg to show in detail which climate information is still preserved in the rock.

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Cut marks on fossils could be evidence of humans exploiting large mammals in Argentina more than 20,000 years ago, according to a new study.

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New research has examined the fossil record going back 66 million years and tracked changes to mammalian ecosystems and species diversity on the North American continent.

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As the planet continues to warm due to human-driven climate change, accurate computer climate models will be key in helping illuminate exactly how the climate will continue to be altered in the years ahead.

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An international research team has assembled the genome and 3D chromosomal structures of a 52,000-year-old woolly mammoth -- the first time such a feat has been achieved for any ancient DNA sample. The fossilized chromosomes, which are around a million times longer than most ancient DNA fragments, provide insight into how the mammoth's genome was organized within its living cells and which genes were active within the skin tissue from which the DNA was extracted. This unprecedented level of structural detail was retained because the mammoth underwent freeze-drying shortly after it died, which meant that its DNA was preserved in a glass-like state.

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Age data for certain classes of meteorite have made it possible to gain new findings on the origin of small water-rich astronomical bodies in the early solar system. These planetesimals continually supplied building materials for planets -- also for the Earth, whose original material contained little water. The Earth received its actual water through planetesimals, which emerged at low temperatures in the outer solar system, as shown by computational models carried out by an international research teach with participation by earth scientists.

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Meet Gaiasia jennyae, the swamp creature with a toilet seat-shaped head. It lived 40 million years before the first dinosaurs, and it was the top predator in its ecosystem.

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Bone remains found in a Tibetan cave 3,280 m above sea level indicate an ancient group of humans survived here for many millennia.

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Two samples from Mars together deliver clear evidence of the origin of Martian organic material. The study presents solid evidence for a prediction made over a decade ago that could be key to understanding how organic molecules, the foundation of life, were first formed here on Earth.

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Human hunting, not climate change, played a decisive role in the extinction of large mammals over the last 50,000 years. This conclusion comes from researchers who reviewed over 300 scientific articles from many different fields of research.

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Hydrothermal vents can be found around the world at the junctions of drifting tectonic plates. But there are many hydrothermal fields still to be discovered. During a 2022 expedition of the MARIA S. MERIAN, the first field of hydrothermal vents on the 500-kilometer-long Knipovich Ridge off the coast of Svalbard was discovered.

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The last population of woolly mammoths was isolated on Wrangel Island off the coast of Siberia 10,000 years ago, when sea levels rose and cut the mountainous island off from the mainland. A new genomic analysis reveals that the isolated mammoths, who lived on the island for the subsequent 6,000 years, originated from at most 8 individuals but grew to 200--300 individuals within 20 generations. The researchers report that the Wrangel Island mammoths' genomes showed signs of inbreeding and low genetic diversity but not to the extent that it can explain their ultimate (and mysterious) extinction.

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Why did multicellularity arise? Solving that mystery may help pinpoint life on other planets and explain the vast diversity and complexity seen on Earth today, from sea sponges to redwoods to human society. A new article shows how specific physical conditions -- especially ocean viscosity and resource deprivation -- during the global glaciation period known as Snowball Earth could have driven eukaryotes to turn multicellular.

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Scientists predict from geochemical data that Iceland is entering a new volcanic era that will last for decades, possibly centuries. Under an hour's drive from the country's capital city, the ongoing eruptions pose considerable risks for economic disruption, and they leave evacuated communities uncertain of a possible return.

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Scientists are rethinking the evolution of vocal learning in birds. New Zealand's smallest bird, the rifleman or titipounamu, may have a rudimentary version of the talent possessed by parrots, hummingbirds and songbirds.