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Categories: Biology: Evolutionary, Physics: Acoustics and Ultrasound

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Researchers have identified microstructures in fossil cells that are 1.75 billion years old. These structures, called thylakoid membranes, are the oldest ever discovered. They push back the fossil record of thylakoids by 1.2 billion years and provide new information on the evolution of cyanobacteria which played a crucial role in the accumulation of oxygen on the early Earth.

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Animals reproduce in one of two distinct ways: egg-laying or live birth. By studying an evolutionarily recent transition from egg-laying to live-bearing in a marine snail, collaborative research has shed new light on the genetic changes that allow organisms to make the switch.

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Biologists developed a method for illuminating the intricate interactions of the synaptonemal complex in the nematode C. elegans. The authors identified a trio of protein segments that guide chromosomal interactions, and pinpointed the location where they interact with each other. Their novel method uses a technique known as genetic suppressor screening, which can serve as a blueprint for research on large cellular assemblies that resist traditional structural analysis.

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Primate social organization is more flexible than previously assumed. According to a new study, the first primates probably lived in pairs, while only around 15 percent of individuals were solitary.

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At about the size of a pinkie nail, the jellyfish species Cladonema can regenerate an amputated tentacle in two to three days -- but how? Regenerating functional tissue across species, including salamanders and insects, relies on the ability to form a blastema, a clump of undifferentiated cells that can repair damage and grow into the missing appendage. Jellyfish, along with other cnidarians such as corals and sea anemones, exhibit high regeneration abilities, but how they form the critical blastema has remained a mystery until now.

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Researchers describe unusual trilobite fossils prepared as thin sections showing the 3D soft tissues during enrollment. The study reveals the soft undersides of enrolled trilobites and the evolutionary mechanism that allows arthropods to enroll their bodies for protection from predators and adverse environmental conditions.

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Researchers have studied the relationships between five closely related species of larks that occur in Africa south of the Sahara. Two of these have not been observed for decades, so the researchers analyzed DNA from museum specimens, some of which were over 100 years old.

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Aquaporin (Aqp) 10 water channels in humans allow the free passage of water, glycerol, urea, and boric acid across cells. However, Aqp10.2b in pufferfishes allows only the passage of water and glycerol and not urea and boric acid. Researchers sought to understand the evolutionary timeline that resulted in the variable substrate selection mechanisms among Aqp10s. Their results indicate that Aqp10.2 in ray-finned fishes may have reduced or lost urea and boric acid permeabilities through evolution.

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Wild North American grapes are now less of a mystery after researchers decoded and catalogued the genetic diversity of nine species of this valuable wine crop.

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Plants often develop communities with microorganisms in their roots, which influences plant health and development. Although the recruitment of these microbes is dictated by several factors, it is unclear whether the genetic variation in the host plants plays a role.

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An international team of scientists led by geneticists and disease biologists has used ancient DNA to trace the evolution of Marek's Disease Virus (MDV). This global pathogen causes fatal infections in unvaccinated chickens and costs the poultry industry over $1 billion per year. The findings show how viruses evolve to become more virulent and could lead to the development of better ways to treat viral infections.

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Researchers have developed a theoretical framework that can reproduce and predict the patterns associated with gastrulation in a chicken embryo.   

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A new study of the remains of prehistoric and modern African antelopes found that AI technology accurately identified animals more than 90% of the time compared to humans, who had much lower accuracy rates depending on the expert.

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Researchers have determined the structure of the most common material in our genomes. New treatments for autoimmune diseases, cancer and neurodegeneration may follow.

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Researchers have come one step closer to unlocking the potential of synthetic DNA, which could help scientists develop never-before-seen proteins in the lab.

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In a comparative analysis across vertebrates of the many cell types in the retina -- mice alone have 130 types -- researchers concluded that most cell types have an ancient evolutionary history. Their remarkable conservation across species suggests that the retina of the last common ancestor of all mammals, which roamed the earth some 200 million year ago, must have had a complexity rivaling the retina of modern mammals.

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The complexity of living organisms is encoded within their genes, but where do these genes come from? Researchers resolved outstanding questions regarding the origin of small regulatory genes, and described a mechanism that creates their DNA palindromes. Under suitable circumstances, these palindromes evolve into microRNA genes.

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Paleontologists are getting a glimpse at life over a billion years in the past based on chemical traces in ancient rocks and the genetics of living animals. New research combines geology and genetics, showing how changes in the early Earth prompted a shift in how animals eat.

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Engineers have developed a bio-compatible ink that solidifies into different 3D shapes and structures by absorbing ultrasound waves. Because the material responds to sound waves rather than light, the ink can be used in deep tissues for biomedical purposes ranging from bone healing to heart valve repair.

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The sound a disc makes while soaring through the air is full of information about how fast the disc is flying and how quickly it spins. This inspired Kyle S. Dalton of Penn State University to combine disc golf and acoustics into an interactive acoustic signal processing lesson. He set three microphones in a line and connected them to equipment that converts each microphone's signal to a data point. Then he threw a disc with a small whistle mounted on top and recorded the flying disc's acoustical signal. The resulting dataset can be used to learn basic processing tools and practice data visualization.