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Categories: Biology: Molecular, Offbeat: Paleontology and Archeology
Published Where to put head and tail?
(via sciencedaily.com) Original source Formation of the body axes is a critical part of embryonic development. They guarantee that all body parts end up where they belong and that no ears grow on our backs. The head-tail axis, for example, determines the orientation of the two ends of the body. It was previously assumed that this axis is largely determined by the interplay between the Nodal and BMP signals. However, there appears to be another player in this system, as researchers have now discovered by using an embryo-like model system they developed. In the absence of BMP, the signalling molecule beta-catenin takes on the role of the Nodal antagonist. This new mechanism could be a flexible solution for axis formation in embryos with different shapes.
Published How the ketogenic diet improves healthspan and memory in aging mice
(via sciencedaily.com) Original source The ketogenic diet has its fanatics and detractors among dieters, but either way, the diet has a scientifically documented impact on memory in mice. While uncovering how the high fat, low carbohydrate diet boosts memory in older mice, scientists identified a new molecular signaling pathway that improves synapse function and helps explain the diet's benefit on brain health and aging.
Published Ancient polar sea reptile fossil is oldest ever found in Southern Hemisphere
(via sciencedaily.com) Original source An international team of scientists has identified the oldest fossil of a sea-going reptile from the Southern Hemisphere -- a nothosaur vertebra found on New Zealand's South Island. 246 million years ago, at the beginning of the Age of Dinosaurs, New Zealand was located on the southern polar coast of a vast super-ocean called Panthalassa. 'The nothosaur found in New Zealand is over 40 million years older than the previously oldest known sauropterygian fossils from the Southern Hemisphere.
Published The genetic 'switches' of bone growth
(via sciencedaily.com) Original source In mammals, only 3% of the genome consists of coding genes which, when transcribed into proteins, ensure the biological functions of the organism and the in-utero development of future individuals. But genes do not function alone. They are controlled by other sequences in the genome, called enhancers, which, like switches, activate or deactivate them as required. A team has now identified and located 2700 enhancers -- among millions of non-coding genetic sequences -- that precisely regulate the genes responsible for bone growth. This discovery sheds light on one of the major factors influencing the size of individuals in adulthood, and explains why their failure could be the cause of certain bone malformations.
Published Sharks have depleted functional diversity compared to the last 66 million years
(via sciencedaily.com) Original source New research has found that sharks retained high levels of functional diversity for most of the last 66 million years, before steadily declining over the last 10 million years to its lowest value in the present day.
Published The rotation of Earth's inner core has slowed, new study confirms
(via sciencedaily.com) Original source The new study provides unambiguous evidence that the inner core began to decrease its speed around 2010, moving slower than the Earth's surface.
Published Paleontology: New fossil fish genus discovered
(via sciencedaily.com) Original source Paleontologists have identified a new genus of fossil goby, revealing evolutionary secrets of a lineage that stretches back millions of years.
Published The gender gap in life expectancy: Are eggs and sperm partly responsible?
(via sciencedaily.com) Original source Researchers have found that germ cells, which develop into eggs and sperm, drive sex-dependent differences in lifespan in vertebrates. Female and male germ cells increase and reduce lifespan, respectively. These effects are controlled via estrogen and growth factor hormones in females and vitamin D in males. Vitamin D supplementation extends lifespan in both males and females. The results clarify the link between reproduction and aging and show that vitamin D may improve longevity in vertebrates.
Published A mountainous mystery uncovered in Australia's pink sands
(via sciencedaily.com) Original source Deposits of deep-pink sand washing up on South Australian shores shed new light on when the Australian tectonic plate began to subduct beneath the Pacific plate, as well as the presence of previously unknown ancient Antarctic mountains.
Published No bones about it: 100-million-year-old bones reveal new species of pterosaur
(via sciencedaily.com) Original source New research has identified 100-million-year-old fossilized bones discovered in western Queensland as belonging to a newly identified species of pterosaur, which was a formidable flying reptile that lived among the dinosaurs.
Published Ritual sacrifice at Chichén Itzá
(via sciencedaily.com) Original source Rising to power in the wake of the Classic Maya collapse, Chichen Itz was among the largest and most influential cities of the ancient Maya, but much about its political connections and ritual life remain poorly understood. Close kin relationships, including two pairs of identical twins, suggests a connection to the Maya origin myths of the Popol Vuh.
Published Scientists engineer yellow-seeded camelina with high oil output
(via sciencedaily.com) Original source Using tools of modern genetics, plant biochemists have produced a new high-yielding oilseed crop variety -- a yellow-seeded variety of Camelina sativa, a close relative of canola, that accumulates 21.4% more oil than ordinary camelina.
Published Virus-like nanoparticles control the multicellular organization and reproduction of host bacteria
(via sciencedaily.com) Original source Researchers have discovered that virus-like nanoparticles can promote the multicellular organization and reproduction of host bacteria. These particles, which are evolutionarily related to phages (viruses that infect bacteria), contain an enzyme that helps shape the multicellular architecture and ultimately enhances morphological differentiation.
Published Algae offer real potential as a renewable electricity source
(via sciencedaily.com) Original source The need to transition away from fossil fuels to more sustainable energy production is critical. That's why a team of researchers is looking at a potential power source that not only produces no carbon emissions but removes carbon as it works: algae.
Published Scientists unlock secrets of how archaea, the third domain of life, makes energy
(via sciencedaily.com) Original source An international scientific team has redefined our understanding of archaea, a microbial ancestor to humans from two billion years ago, by showing how they use hydrogen gas. The findings explain how these tiny lifeforms make energy by consuming and producing hydrogen. This simple but dependable strategy has allowed them to thrive in some of Earth's most hostile environments for billions of years.
Published Protein study could help researchers develop new antibiotics
(via sciencedaily.com) Original source A team has found a way to make the bacterial enzyme histidine kinase water-soluble, which could make it possible to rapidly screen potential antibiotics that might interfere with its functions.
Published How human derived RNA fragments help the Hepatitis E virus
(via sciencedaily.com) Original source Why does Hepatitis E become chronic in some patients, and why do medications not work? To find out, an international research team led by scientists from Bochum observed a patient with chronic Hepatitis E infection over a year. Repeated sequencing of the virus RNA showed that the virus incorporated various parts of the host's messenger RNA into its genome. This resulted in a replication advantage, which may have contributed to the infection becoming chronic.
Published The solar system may have passed through dense interstellar clouds 2 million years ago, altering Earth's climate
(via sciencedaily.com) Original source Astrophysicists calculate the likelihood that Earth was exposed to cold, harsh interstellar clouds, a phenomenon not previously considered in geologic climate models.
Published Novel Genetic Clock discovers oldest known marine plant
(via sciencedaily.com) Original source An international research team has discovered the oldest known marine plant using a novel genetic clock. This 1400-year-old seagrass clone from the Baltic Sea dates back to the Migration Period. The research project is a significant step towards better understanding and protecting marine ecosystems.
Published A protein that enables smell--and stops cell death
(via sciencedaily.com) Original source While smell plays a considerable role in the social interactions of humans -- for instance, signaling fear or generating closeness -- for ants, it is vitally important. Researchers have found that a key protein named Orco, essential for the function of olfactory cells, is also critical for the cells' survival in ants.