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Categories: Biology: Developmental, Offbeat: Paleontology and Archeology

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The sharks we know today as the open ocean's top predators evolved from stubby bottom dwellers during a dramatic episode of global warming millions of years ago.

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One of Earth's most consequential bursts of biodiversity -- a 30-million-year period of explosive evolutionary changes spawning innumerable new species -- may have the most modest of creatures to thank for the vital stage in life's history: worms.

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A new study has uncovered a diverse array of microorganisms within the hot waters of the Roman Baths, regularly listed among the UK's most popular tourist attractions. Tests showed 15 of the isolated bacteria -- including examples of Proteobacteria and Firmicutes -- displayed varying levels of inhibition against human pathogens including E.coli, Staphylococcus Aureus and Shigella flexneri.

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This fossil looks like a lumpy, rounded rock with a couple of exposed teeth that are a little worse for wear, having been submerged and tumbled along the floor of the Gulf of Mexico for thousands of years before washing up on a beach. But when it was X-rayed a doctoral student saw there was more to the fossil that met the eye: a hidden canine tooth that had not yet erupted from the jaw bone. It was just what researchers needed to identify the fossil as belonging to a Homotherium, a genus of large cat that roamed much of the Earth for millions of years.

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A large fossil discovery has helped shed light on the history of dinosaurs in Wales.

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A whaler's forgotten aerial photos from 1937 have given researchers the most detailed picture of the ice evolution in East Antarctica to date. The results show that the ice has remained stable and even grown slightly over almost a century, though scientists observe early signs of weakening. The research offers new insights that enhance predictions of ice changes and sea level rise.

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The benefits gained with higher lifestyle scores may be associated with the positive influence of heart disease risk factors on the aging of the body and its cells, finds a new study in the Journal of the American Heart Association

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A new deep learning model performs a task that biologists have struggled with for centuries -- how to measure the incredibly complex process of embryonic development. Scientists have shown that the AI model, known as Dev-ResNet, can identify what happens and when during embryonic development, from video. While used in pond snail embryos for this study, in future the technique could be used to help accelerate understanding on how climate change, and other external factors, affect humans and animals in the earliest stages of life.

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Researchers have demonstrated how B cells infected with the Epstein-Barr virus (EBV) can contribute to a pathogenic, inflammatory phenotype that contributes to multiple sclerosis (MS); the group has also shown how these problematic B cells can be selectively targeted in a way that reduces the damaging autoimmune response of multiple sclerosis.

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Researchers found that approximately one in 40 human bone marrow cells carry massive chromosomal alterations without causing any apparent disease or abnormality. Even so-called normal cells carry all sorts of genetic mutations, meaning there are more genetic differences between individual cells in our bodies than between different human beings. The discovery was enabled by a single-cell sequencing technology called Strand-seq, a unique DNA sequencing technique that can reveal subtle details of genomes in single cells that are too difficult to detect with other methods.

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Scientists have developed a new method that can manipulate the movement of embryonic cells using short-time attractors.

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The African turquoise killifish lives in ephemeral ponds in Zimbabwe and Mozambique. To survive the annual dry season, the fish's embryos enter a state of extreme suspended animation or 'diapause' for approximately 8 months. Now, researchers have uncovered the mechanisms that enabled the killifish to evolve this extreme survival state.

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An exceptionally rare fossilized porcupine skeleton discovered in Florida has allowed researchers to trace the evolutionary history for one of North America's rarest mammals.

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While most organisms have biological clocks synchronized with the day-night cycle (circadian rhythms), marine animals in tidal areas have also developed circatidal rhythms to align with the tidal cycle. Comparing the activity and genetic expression of snails from tidal and non-tidal areas, researchers demonstrate that circatidal rhythms develop as snails adapt to tidal environments. These findings highlight the flexibility of biological clocks, enabling organisms to adjust their rhythms according to the environment.

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Entomologists have solved the 250-year-old origin puzzle of the most prevalent indoor urban pest insect on the planet: the German cockroach. The team's research findings, representing the genomic analyses of over 280 specimens from 17 countries and six continents, show that this species evolved some 2,100 years ago from an outdoor-living species in Asia.

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Biologists have provided new insights on a longstanding puzzle in biology: How complex organisms arise from a single fertilized cell. Producing a new 'gene atlas' with 4-D imaging, the researchers captured unprecedented insights on how embryonic development unfolds.

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Humans have been long fascinated by bird song and the cacophony of other avian sounds -- from coos and honks to quacks and peeps. But little is known about how the unique vocal organ of birds -- the syrinx -- varies from species to species or its deeper evolutionary origins. A trio of recent studies is changing that. The studies include high-resolution anatomical scans of syrinxes from hummingbirds and ostriches -- the world's smallest and largest bird species -- and the discovery that the syrinx and larynx, the vocal organ of reptiles and mammals, including humans, share the same developmental programming.

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Multicellular organisms, like animals and plants, have complex cells with diverse functions. This complexity arises from the need for cells to produce distinct proteins that interact with each other. This interaction is crucial for cells to carry out their specific tasks and to form complex molecular machinery. However, our current understanding of such protein-protein interactions often lacks cellular contexts because they were usually studied in an in vitro system or in cells isolated from their tissue environment. Effective methods to investigate protein-protein interactions in a tissue-specific manner are largely missing.

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Treatment of autoimmune diseases like lupus has long relied on steroids to knock down the immune system, but more targeted therapies are currently undergoing clinical trials. To make sure these therapies get to the patients who will benefit, work is needed to identify the specific mutations behind each patient's disease. Researchers now report several dozen mutations associated with oversensitive toll-like receptors -- a major cause of autoimmune disease -- and linked two mutations to patients.

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Animals and fungi predominantly use two different modes of cell division -- called open and closed mitosis, respectively. A new study has shown that different species of Ichthyosporea -- marine protists that are close relatives of both animals and fungi -- use either open and closed mitosis, closely correlated to whether the species has multinucleate life cycle stages. The study demonstrates the way animals do cell division might have evolved long before animals themselves did and how this is linked to an organism's life cycle.