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Categories: Paleontology: Early Mammals and Birds, Physics: Optics

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Researchers have finally settled a decades-long dispute about the evolutionary origins of the pygmy right whale.

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Birds are the only group of dinosaurs that survived the asteroid-induced mass extinction 66 million years ago. But not all the birds alive at the time made it. Why the ancestors of modern birds lived while so many of their relatives died has been a mystery that paleontologists have been trying to solve for decades. Two new studies point to one possible factor: the differences between how modern birds and their ancient cousins molt their feathers.

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The lower jaws of lizards, birds, fish and even dinosaurs are comprised of multiple bones per side. Yet mammals diverged from all other vertebrates and settled on just one bone, repurposing the extra bones into a more elaborate inner ear, perhaps the better to hear. The single bone per side, fused in primates into one jawbone, makes the jaw more rigid. A paleontologist asks, Did the stiffer, rigid jaw make mammals more successful?

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A Cretaceous origin for placental mammals, the group that includes humans, dogs and bats, has been revealed by in-depth analysis of the fossil record, showing they co-existed with dinosaurs for a short time before the dinosaurs went extinct.

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How the megalodon, a shark that went extinct 3.6 million years ago, stayed warm was a matter of speculation among scientists. Using an analysis of tooth fossils from the megalodon and other sharks of the same period, a study suggests the animal was able to maintain a body temperature well above the temperature of the water in which it lived. The finding could help explain why the megalodon went extinct during the Pliocene Epoch.

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The Bachman's warbler, a songbird that was last seen in North America nearly 40 years ago, was a distinct species and not a hybrid of its two living sister species, according a new study in which the full genomes of seven museum specimens of the bird were sequenced.

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Researchers have developed a metasurface that enables strong coupling effects between light and transition metal dichalcogenides (TMDCs).

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Researchers have outlined a new high-speed tunable microcomb that could help propel advances in wireless communication, imaging, atomic clocks, and more.

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Scientists have demonstrated a capability long sought by physicists: transmitting extremely precise time signals through the air between far-flung locations at powers that are compatible with future space-based missions. The results could enable time transfer from the ground to satellites in geosynchronous orbit with femtosecond precision -- 10,000 times better than the existing state-of-the-art satellite approaches. It also would allow for successful synchronization using the bare minimum timing signal strength, which would make the system highly robust in the face of atmospheric disturbances.

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A study demonstrates that graphene-based materials can be used to efficiently convert high-frequency signals into visible light, and that this mechanism is ultrafast and tunable. These outcomes open the path to exciting applications in near-future information and communication technologies.

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A new process enables printing of nanometer-scale quartz glass structures directly onto semiconductor chips. A hybrid organic-inorganic polymer resin is used as feedstock material for 3D printing of silicon dioxide. Since the process works without sintering, the required temperatures are significantly lower. Simultaneously, increased resolution enables visible-light nanophotonics.

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A cutting-edge experiment has revealed the quantum dynamics of one of nature's most crucial processes.

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A new class of materials that can absorb low energy light and transform it into higher energy light might lead to more efficient solar panels, more accurate medical imaging and better night vision goggles.

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Scientists used a new invariant property of vectorial light to encode information. This quantity, which the team call 'vectorness', scales from 0 to 1 and remains unchanged when passing through a noisy channel.

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New findings settle the dispute: phonons can be chiral. This fundamental concept, discovered using circular X-ray light, sees phonons twisting like a corkscrew through quartz.

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A groundbreaking new paper focuses on the size and abundance of living and fossil African large mammals, shedding light on the ecological dynamics behind the decline of these iconic creatures. The findings challenge previous assumptions about the causes of megafaunal extinctions in Africa and provide new insights into the restructuring of ecosystems over millions of years.

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Researchers have demonstrated the principle of using spatial correlations in quantum entangled beams of light to encode information and enable its secure transmission.

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Would you rather run into a brick wall or into a mattress? For most people, the choice is not difficult. A brick wall is stiff and does not absorb shocks or vibrations well; a mattress is soft and is a good shock absorber. Sometimes, in designing materials, both of these properties are needed. Materials should be good at absorbing vibrations, but should be stiff enough to not collapse under pressure. A team of researchers from the UvA Institute of Physics has now found a way to design materials that manage to do both these things.

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Researchers have gained new insights into the unique chemical properties of spherical molecules composed entirely of carbon atoms, called fullerenes. They did it by making flat fragments of the molecules, which surprisingly retained and even enhanced some key chemical properties.

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Researchers have discovered they can detect atomic 'breathing,' or the mechanical vibration between two layers of atoms, by observing the type of light those atoms emitted when stimulated by a laser. The sound of this atomic 'breath' could help researchers encode and transmit quantum information.