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Categories: Mathematics: Modeling, Paleontology: Fossils

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Microorganisms were the first forms of life on our planet. The clues are written in 3.5 billion-year-old rocks by geochemical and morphological traces, such as chemical compounds or structures that these organisms left behind. However, it is still not clear when and where life originated on Earth and when a diversity of species developed in these early microbial communities. Evidence is scarce and often disputed. Now, researchers have uncovered key findings about the earliest forms of life. In rock samples from South Africa, they found evidence dating to around 3.42 billion years ago of an unprecedentedly diverse carbon cycle involving various microorganisms. This research shows that complex microbial communities already existed in the ecosystems during the Palaeoarchaean period.

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Human pathologists are extensively trained to detect when tissue samples from one patient mistakenly end up on another patient's microscope slides (a problem known as tissue contamination). But such contamination can easily confuse artificial intelligence (AI) models, which are often trained in pristine, simulated environments, reports a new study. Each of the four AI models in the study paid too much attention to the tissue contamination, which resulted in errors when diagnosing or detecting vessel damage, gestational age, lesions and prostate cancer, the study found.

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Of all the organisms that photosynthesize, land plants have the most complex form. How did this morphology emerge? A team of scientists has taken a deep dive into the evolutionary history of morphological complexity in streptophytes, which include land plants and many green algae. Their research allowed them to go back in time to investigate lineages that emerged long before land plants existed.

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A newly published study provides guidance for building accurate mathematical models for gene regulatory networks.

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Gliding winged-reptiles were amongst the ancient crocodile residents of the Mendip Hills in Somerset, England, researchers at the have revealed.

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A new study shows the Megalodon, a gigantic shark that went extinct 3.6 million years ago, was more slender than earlier studies suggested. This finding changes scientists' understanding of Megalodon behavior, ancient ocean life, and why the sharks went extinct.

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The new theoretical research proposes that animal size over time depends on two key ecological factors.

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Cancer resists treatment in a multitude of ways, but a new algorithm developed can decode them all simultaneously.

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New insights from artificial intelligence about permafrost coverage in the Arctic may soon give policy makers and land managers the high-resolution view they need to predict climate-change-driven threats to infrastructure such as oil pipelines, roads and national security facilities.

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Researchers have linked the travels of a 14,000-year-old woolly mammoth with the oldest known human settlements in Alaska, providing clues about the relationship between the iconic species and some of the earliest people to travel across the Bering Land Bridge. Isotopic data, along with DNA from other mammoths at the site and archaeological evidence, indicates that early Alaskans likely structured their settlements to overlap with areas where mammoths congregated. Those findings, highlighted in the new issue of the journal Science Advances, provide evidence that mammoths and early hunter-gatherers shared habitat in the region. The long-term predictable presence of woolly mammoths would have attracted humans to the area.

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Fossils of kelp along the Pacific Coast are rare. Until now, the oldest fossil dated from 14 million years ago, leading to the view that today's denizens of the kelp forest -- marine mammals, urchins, sea birds -- coevolved with kelp. A recent amateur discovery pushes back the origin of kelp to 32 million years ago, long before these creatures appeared. A new analysis suggests the first kelp grazers were extinct, hippo-like animals called desmostylians.

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New research has precisely dated some of the oldest fossils of complex multicellular life in the world, helping to track a pivotal moment in the history of Earth when the seas began teeming with new lifeforms -- after four billion years of containing only single-celled microbes.

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The sun has just set on a quiet mudflat in Australia's Northern Territory; it'll set again in another 19 hours. A young moon looms large over the desolate landscape. No animals scurry in the waning light. No leaves rustle in the breeze. No lichens encrust the exposed rock. The only hint of life is some scum in a few puddles and ponds. And among it lives a diverse microbial community of our ancient ancestors.

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Researchers have identified a 3D fragment of fossilized skin that is at least 21 million years than previously described skin fossils. The skin, which belonged to an early species of Paleozoic reptile, has a pebbled surface and most closely resembles crocodile skin. It's the oldest example of preserved epidermis, the outermost layer of skin in terrestrial reptiles, birds, and mammals, which was an important evolutionary adaptation in the transition to life on land.

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Researchers have developed a new technique to measure the number of chromosomes in ancient genomes more precisely, using it to identify the first prehistoric person with mosaic Turner syndrome (characterized by one X chromosome instead of two [XX]), who lived about 2500 years ago.

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Picrodontids -- an extinct family of placental mammals that lived several million years after the extinction of the dinosaurs -- are not primates as previously believed.

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The largest ever primate Gigantopithecus blacki went extinct when other Asian great apes were thriving, and its demise has long been a mystery. A massive regional study of 22 caves in southern China explores a species on the brink of extinction between 295,000 and 215,000 years ago. As the environment became more seasonal, forest plant communities changed Primates such as orangutans adapted their eating habits and behaviors in response but G. blacki showed signs of stress, struggled to adapt and their numbers dwindled.

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In an effort to make the internet more accessible for people with disabilities, researchers have begun developing an artificial intelligence agent that could complete complex tasks on any website using simple language commands.

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Researchers have developed a groundbreaking artificial intelligence (AI) system that can rapidly detect COVID-19 from chest X-rays with more than 98 percent accuracy.

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Researchers are presenting a novel concept for the mathematical modeling of genetic interactions in biological systems. The team has successfully identified master regulators within the context of an entire genetic network. The research results provide a coherent theoretical framework for analyzing biological networks.