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Categories: Biology: General, Paleontology: Climate

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Maize is one of the world's most widely grown crops. It is used for both human and animal foods and holds great cultural significance, especially for indigenous peoples in the Americas. Yet despite its importance, the origins of the grain have been hotly debated for more than a century. Now new research shows that all modern maize descends from a hybrid created just over 5000 years ago in central Mexico, thousands of years after the plant was first domesticated.

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Identifying how and why Antarctica's major ice sheets behaved the way they did in the early Miocene could help inform understanding of the sheets' behavior under a warming climate. Together, the ice sheets lock a volume of water equivalent to more than 50 meters of sea level rise and influence ocean currents that affect marine food webs and regional climates. Their fate has profound consequences for life nearly everywhere on Earth.  

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A recent study demonstrates how dripstones can be crucial for reconstructing past climates. The new approach can provide a detailed picture of the climate around early human occupations in South Africa.

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There's a species of ant that is so rare, only a handful of records exist from across the entire eastern United States. North Carolina State University researcher Michelle Kirchner not only found these ants in the Triangle region of North Carolina, she is the first to document an entire colony for scientists, taxonomists and ant-thusiasts everywhere. It is the first time males of the species have been collected or photographed.

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Researchers have discovered that the waxy protective barrier around plants might play a role in sending chemical signals to other plants and insects.  

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A new study tackles the mystery of why bacteria often carry diverse ranges of weapons. The findings show that different weapons are best suited to different competition scenarios. Short-range weapons help bacteria to invade established communities; long-range weapons are useful once established.

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A new bacterial species discovered at the deep-sea hydrothermal vent site 'Crab Spa' provides a deeper understanding of bacterial evolution.

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Scientists have analyzed more than 3.8 million volunteer hours of birdwatching data to identify Australia's most elusive species.

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We humans are fixated on big brains as a proxy for smarts. But headless animals called brittle stars have no brains at all and still manage to learn through experience, new research reveals. These shy marine creatures have no brain to speak of -- just nerve cords running down each of their five wiggly arms. But that seems to be enough to learn by association, researchers report.    

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Researchers are homing in on the neurons, circuits, and mechanisms responsible for persistent aggression in fruit flies. 

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The San Joaquin Valley in California has experienced vast variability in climate extremes, with droughts and floods that were more severe and lasted longer than what has been seen in the modern record, according to a new study of 600 years of tree rings from the valley.

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The Second Plague Pandemic of the mid-14th century, also known as the Black Death, killed 30-60 percent of the European population and profoundly changed the course of European history. New research suggests that this plague, potentially through resulting changes in diet and hygiene, may also be associated with a shift in the composition of the human oral microbiome toward one that contributes to chronic diseases in modern-day humans.  

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Researchers have uncovered a mechanism that safeguards the biallelic expression of haploinsufficient genes, shedding light on the importance of having two copies of each chromosome. A study identified the epigenetic regulator MSL2 an 'anti-monoallelic' factor that maintains biallelic gene dosage. This discovery not only reveals a communication system between parental alleles but also points to potential therapeutic strategies for diseases associated with haploinsufficient genes.

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New research identifies the class II PI3K-C2b protein, a member of the PI3 family of kinases, as one of the key regulators of blood vessels growth in humans and other mammals. Mutations in these family of proteins may lead to vascular malformations and the precise understanding of the whole process is instrumental in opening the door to new therapeutic approaches in the future.

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Fruit and vegetables contain a variety of plant natural products such as flavonoids, which give fruits their colour and are said to have health-promoting properties. Most plant natural products occur in nature as glycosides, i.e. chemical compounds with sugars. In order for humans to absorb the healthy plant natural products, the sugar must be split off in the intestine. Microorganisms in the intestinal flora help to speed up the process. So-called C-glycosides, i.e. plant natural products with a carbon-based bond to a sugar, would even be practically indigestible without the intestinal microbes (e.g. nothofagin in rooibos tea).

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Enzymes from microorganisms can produce hydrogen (H2) under certain conditions, which makes them potential biocatalysts for biobased H2 technologies. In order to make this hydrogen production efficient, researchers are trying to identify and eliminate possible limiting factors. These include formaldehyde, which occurs naturally as a metabolic product in cells and inhibits the particularly efficient [FeFe] hydrogenase.

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New research has provided a detailed examination of England's bottlenose dolphin population's existence and the challenges it faces from human activities and environmental factors on a daily basis.

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Bees, wasps and ants belong to the Hymenoptera order and inject a whole cocktail of venomous ingredients when they sting. Despite their tremendous ecological and economic importance, little was previously known about the origins of their venom. Through extensive genomic studies, a team of researchers has now discovered that typical venomous components were already present in the earliest ancestors of Hymenoptera and must therefore have evolved before the stingers of bees and other insects. What's more, and contrary to previous assumptions, the gene for the venom melittin is found solely in bees.

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A landmark study into the geological timescale distribution of sediment and nutrients over 500 million years shows that species biodiversity on Earth is driven by landscape dynamics.

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The evolution of higher cognitive functions in humans has so far mostly been linked to the expansion of the neocortex. Researchers are increasingly realizing, however, that the 'little brain' or cerebellum also expanded during evolution and probably contributes to the capacities unique to humans. A research team has now generated comprehensive genetic maps of the development of cells in the cerebella of human, mouse and opossum. Comparisons of these maps reveal both ancestral and species-specific cellular and molecular characteristics of cerebellum development.