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Categories: Biology: Developmental, Biology: Evolutionary

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Genetic manipulation of a puzzling, miniscule bacteria that has lived in human mouths at least since the Middle Stone Age is elucidating the genes needed for its unusual lifestyle. These Patescibacteria in the human oral microbiome reside on the surface of another, larger host microbe. Found in many water and land environments, Patescibacteria in general lack the genes required to make many molecules necessary for life, such as the amino acids that make up proteins, the fatty acids that form membranes, and the nucleotides in DNA. This has led researchers to speculate that many of them rely on other bacteria to grow. In a new study, researchers present the first glimpse into the molecular mechanisms behind their relationship with their host cells. They also share details gleaned from fluorescent, time-lapse microsopic imaging of these bacteria as they bud and send out swarms of tiny progeny, only a fraction of which are able to establish a host relationship.

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Scientists have identified a key part of a mechanism that annotates genetic information before it is passed from fathers to their offspring. The findings shed new light on genomic imprinting, a fundamental, biological process in which a gene from one parent is switched off while the copy from the other parent remains active. Errors in imprinting are linked to a host of diseases, such as the rare disease Silver-Russell syndrome along with certain cancers and diabetes.

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Biomedical scientists have confirmed that newly discovered cells in the thymus are just like M cells, which are mostly known for their presence in the intestinal epithelium.

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Researchers have investigated how the behavior of an individual wheat plant under limiting light conditions influences the performance of the whole community. They assessed morphological and biomass phenotypes of single plants grown in mixtures under sunlight and a simulated canopy shade, and the relevance of these phenotypes for the monoculture community in the field.

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A team of researchers has revealed that the Dumpy protein, a component of extracellular matrices -- or ECM -- is the key factor in regulating the stereotypic origami-like folding of wing-cell sheets. Their findings that wing cells never divide during folding nor do they exhibit spatially distinct behaviors suggest how external cues can create consistent 3D tissue structures.

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Researchers report that the flexible shoulders and elbows that allow us to throw a football or reach a high shelf may have evolved as a natural braking system that let our primate ancestors get out of trees without dying. The researchers used sports-analysis software to compare the climbing movements of chimpanzees and small monkeys called mangabeys. While the animals climb up trees similarly, the researchers found that the shallow, rounded shoulder joints and shortened elbow bones that chimps have -- similar to humans -- allow them to fully extend their arms above their heads when climbing down, holding onto branches like a person going down a ladder to support their greater weight. When early humans left forests for the grassy savanna, these versatile appendages would have been essential for gathering food and using tools for hunting and defense. The findings are among the first to identify the significance of 'downclimbing' in the evolution of apes and early humans.

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A new study has uncovered intriguing insights into the evolution of plant biology, effectively rewriting the history of how they evolved over the past billion years.

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More than 100 years of observations in nature have revealed a universal pattern of species abundances: Most species are rare but not very rare, and only a few species are very common. These so-called global species abundance distributions have become fully unveiled for some well-monitored species groups, such as birds. For other species groups, such as insects, however, the veil remains partially unlifted. A new study demonstrates how important biodiversity monitoring is for detecting species abundances on planet Earth and for understanding how they change.

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When fighting disease, our immune cells need to reach their target quickly. Researchers have now discovered that immune cells actively generate their own guidance system to navigate through complex environments. This challenges earlier notions about these movements. The researchers' findings enhance our knowledge of the immune system and offer potential new approaches to improve human immune response.

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In a new study, researchers used mice to understand how DiNP affects pregnancy.

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An international team of marine scientists has studied the DNA of family groups from four different whale species to estimate their mutation rates. Using the newly determined rates, the group found that the number of humpback whales in the North Atlantic before whaling was 86 percent lower than earlier studies suggested.

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As climate change continues to pose severe challenges to ensuring sustainable food supplies around the world, scientists are looking for ways to improve the resilience and nutritional quality of potatoes. Scientists have assembled the genome sequences of nearly 300 varieties of potatoes and its wild relatives to develop more nutritious, disease-free, and weather-proof crop. A team has now created a potato super pangenome to identify genetic traits that can help produce the next super spud.

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Plant species from certain geographic regions are more successful in spreading outside their native ranges than others -- but why? Ecologists provide answers by exploring how the ecological and evolutionary histories of plants can influence their relationships with humans and their success as invaders.

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Researchers generated large scale gene expression data to investigate the molecular networks that operate in one of the closest algal relatives of land plants, a humble single-celled alga called Mesotaenium endlicherianum.

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We've long known that hosts malfunction without their microbiome -- whether they are missing key microbial species or are completely microbe free. This malfunctioning is usually explained by the need for microbes to perform unique and beneficial functions, but evolutionary ecologist is questioning that narrative.

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When infants are involved in agonistic conflicts, male crested macaques (Macaca nigra) are more likely to respond to screams from their own offspring. This is the conclusion of a recent study led by behavioral ecologists. The researchers studied the behavior of crested macaques in the Tangkoko Nature Reserve on Sulawesi, Indonesia, over a 24-month period (2008 to 2010).

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Scientists use cutting edge scanning technology to reconstruct 'fossil monster' that lived half a billion years ago. The creature's soft anatomy was well-preserved, allowing it to be imaged almost completely: It fills a gap in our understanding of the evolution of arthropods such as insects and crustaceans.

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An international research team has described seven previously unknown species of leaf insects, also known as walking leaves. The insects belong to the stick and leaf insect order, which are known for their unusual appearance: they look confusingly similar to parts of plants such as twigs, bark or -- in the case of leaf insects -- leaves. This sophisticated camouflage provides excellent protection from predators as well as presenting a challenge to researchers. Genetic analysis enabled the researchers to discover 'cryptic species', which cannot be distinguished by their external appearance alone. The findings are not only important for the systematic study of leaf insects, but also for the protection of their diversity.

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Findings can open up new avenues for targeted approaches toward therapeutic strategies against the malaria-causing P. falciparum that are aimed at stopping the parasite's life cycle progression and its sexual differentiation, thus blocking the transmission of the parasite into mosquitoes.

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Researchers have developed and demonstrated a new method for high-throughput single-cell sorting that uses stimulated Raman spectroscopy rather than the traditional approach of fluorescence-activated cell sorting. The new approach could offer a label-free, nondestructive way to sort cells for a variety of applications, including microbiology, cancer detection and cell therapy.