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Categories: Biology: General, Paleontology: Early Mammals and Birds
Published Last surviving woolly mammoths were inbred but not doomed to extinction
(via sciencedaily.com) Original source 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.
Published To protect corals from summer heatwaves, we should help their microbial symbionts evolve heat tolerance in the lab
(via sciencedaily.com) Original source Most coral reef restoration efforts involve restocking reefs with nursery-grown corals. However, if these corals are of the same stock as their wild counterparts, they will be equally vulnerable to the heat stress that caused the bleaching event in the first place. Researchers discuss the potential of improving corals' chances by inducing the evolution of heat tolerance in their symbionts -- the mutualistic microbes that provide corals with nutrients in exchange for shelter and that are expelled during coral bleaching.
Published Pacific cod can't rely on coastal safe havens for protection during marine heat waves
(via sciencedaily.com) Original source During recent periods of unusually warm water in the Gulf of Alaska, young Pacific cod in near shore safe havens where they typically spend their adolescence did not experience the protective effects those areas typically provide, a new study found.
Published Wolves reintroduced to Isle Royale temporarily affect other carnivores, humans have influence as well
(via sciencedaily.com) Original source In a rare opportunity to study carnivores before and after wolves were reintroduced to their ranges, researchers found that the effects of wolves on Isle Royale have been only temporary. And even in the least-visited national park, humans had a more significant impact on carnivores' lives.
Published Invasive ants spread by hitchhiking on everyday vehicles
(via sciencedaily.com) Original source Ants might spread to new locations by stowing away on everyday vehicles. Previously, this was thought to occur mostly on agricultural equipment.
Published A promising weapon against measles
(via sciencedaily.com) Original source What happens when measles virus meets a human cell? The viral machinery unfolds in just the right way to reveal key pieces that let it fuse itself into the host cell membrane.
Published Prehistoric 'Pompeii' discovered: Most pristine trilobite fossils ever found shake up scientific understanding of the long extinct group
(via sciencedaily.com) Original source Researchers have described some of the best-preserved three-dimensional trilobite fossils ever discovered. The fossils, which are more than 500 million years old, were collected in the High Atlas of Morocco and are being referred to by scientists as 'Pompeii' trilobites due to their remarkable preservation in ash.
Published Under pressure: How comb jellies have adapted to life at the bottom of the ocean
(via sciencedaily.com) Original source Researchers have studied the cell membranes of ctenophores ('comb jellies') and found they had unique lipid structures that allow them to live under intense pressure.
Published Potent therapy candidate for fatal prion diseases
(via sciencedaily.com) Original source Scientists have developed a gene-silencing tool that shows promise as a therapy against fatal prion diseases. The tool, a streamlined epigenetic editor, paves the way for a new class of genetic approaches to treat certain diseases.
Published New, holistic way to teach synthetic biology
(via sciencedaily.com) Original source Synthetic biology combines principles from science, engineering and social science, creating emerging technologies such as alternative meats and mRNA vaccines; Deconstructing synthetic biology across scales gives rise to new approach to uniting traditional disciplines; Case studies offer a modular, accessible approach to teaching at different institutions.
Published Why the harsh Snowball Earth kick-started our earliest multicellular ancestors
(via sciencedaily.com) Original source 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.
Published Researchers find genetic stability in a long-term Panamanian hybrid zone of manakin birds
(via sciencedaily.com) Original source We often think of species as separate and distinct, but sometimes they can interbreed and create hybrids. When this happens consistently in a specific area, it forms what's known as a hybrid zone. These zones can be highly dynamic or remarkably stable, and studying them can reveal key insights into how species boundaries evolve -- or sometimes blur. Researchers now describe a hybrid zone between two manakin species in Panama that has overall remained relatively stable over the past 30 years.
Published Brain's 'escape switch' controlled by threat sensitivity dial
(via sciencedaily.com) Original source Neuroscientists have discovered how the brain bidirectionally controls sensitivity to threats to initiate and complete escape behaviour in mice. These findings could help unlock new directions for discovering therapies for anxiety and post-traumatic stress disorder (PTSD).
Published From takeoff to flight, the wiring of a fly's nervous system is mapped
(via sciencedaily.com) Original source Although a fly's motor neurons are few, it performs remarkable aerial and terrestrial feats. A wiring diagram recently created of the motor circuits in the central nervous system of the fruit fly is providing detailed information on how the nerve coordination of leg movements differs from that controlling the wings. Such studies reveal the unexpected complexity of the fly's tiny motor system. They also advance the understanding of how the central nervous system in animals coordinates individual muscles to carry out a variety of behaviors.
Published Scientists discover genetic 'off switch' in legume plants that limits biological ability to source nutrients
(via sciencedaily.com) Original source A genetic 'off switch' that shuts down the process in which legume plants convert atmospheric nitrogen into nutrients has been identified for the first time by a team of international scientists.
Published Cell division: Before commitment, a very long engagement
(via sciencedaily.com) Original source Before a cell commits fully to the process of dividing itself into two new cells, it may ensure the appropriateness of its commitment by staying for many hours -- sometimes more than a day -- in a reversible intermediate state, according to a new discovery. Their revelation of this fundamental feature of biology includes details of its mechanisms and dynamics, which may inform the development of future therapies targeting cancers and other diseases.
Published New tool enables faster, more cost-effective genome editing of traits to improve agriculture sustainability
(via sciencedaily.com) Original source New research had the goal of reducing the time and cost it takes to bring an improved crop to the marketplace to improve agriculture sustainability.
Published Unlocking the world of bacteria
(via sciencedaily.com) Original source Bacteria possess unique traits with great potential for benefiting society. However, current genetic engineering methods to harness these advantages are limited to a small fraction of bacterial species. A team has now introduced a novel approach that can make many more bacteria amenable to genetic engineering. Their method, called IMPRINT, uses cell-free systems to enhance DNA transformation across various bacterial strains.
Published The on-and-off affair in DNA
(via sciencedaily.com) Original source Researchers have discovered that in thale cresses histone H3 lysine-9 (H3K9) methylation, conventionally thought to be a mark of turning off gene transcription, can also turn on gene expression via the interactions of two other proteins and histone marks. The molecular mechanisms demonstrate that rather than functioning as a simple 'off switch,' H3K9 methylation is more like a 'dimmer switch' that fine-tunes DNA transcription. The discovery suggests there might be similar mechanisms in other organisms, too.
Published Slipping a note to a neighbor: The cellular way
(via sciencedaily.com) Original source Study reveals how drug molecules bind in channels between neighboring cells, changing intercellular communication.