University of Bristol, 16 December 2022.

Professor Emily Rayfield, senior co-author:

>“Our analyses reveal that ornithischians – the group that includes many plant-eating species like the horned dinosaurs, the armoured ankylosaurs and the duck-billed dinosaurs – started off as omnivores.

>“And another interesting finding is that the earliest sauropodomorphs, ancestors of the veggie long-necked sauropods like Diplodocus, were carnivores. This shows that herbivory was not ancestral for any of these two lineages, countering traditional hypotheses, and that the diets of early dinosaurs were quite diverse.”

Lead author Dr. Antonio Ballell:

>“We investigated [dinosaur diet] by applying a set of computational methods to quantify the shape and function of the teeth of early dinosaurs and compare them to living reptiles that have different diets. This included mathematically modelling their tooth shapes and simulating their mechanical responses to biting forces with engineering software.”

Professor Mike Benton, co-author:

>“With this battery of methods, we were able to numerically quantify how similar early dinosaurs were to modern animals, providing solid evidence for our inferences of diets. Theropod dinosaurs have pointy, curved and blade-like teeth with tiny serrations, which behaved like those of modern monitor lizards. In contrast, the denticulated teeth of ornithischians and sauropodomorphs are more similar to modern omnivores and herbivores, like iguanas.”

Science Advances, 2022. DOI 10.1126/sciadv.abq5201

15 December 2022.

Excerpt:

>A team led by UdeM astronomers has found evidence that two exoplanets orbiting a red dwarf star are “water worlds,” planets where water makes up a large fraction of the volume.

>The team, led by PhD student Caroline Piaulet of the Trottier Institute for Research on Exoplanets (iREx) at the Université de Montréal, published a detailed study of a planetary system known as Kepler-138 in the journal Nature Astronomy today.

>Water wasn’t directly detected, but by comparing the sizes and masses of the planets [Kepler-138c and d] to models, they conclude that a significant fraction of their volume — up to half of it — should be made of materials that are lighter than rock but heavier than hydrogen or helium (which constitute the bulk of gas giant planets like Jupiter).

>The most common of these candidate materials is water.

> 

>The closest comparison to the two planets, say researchers, would be some of the icy moons in the outer solar system that are also largely composed of water surrounding a rocky core.

>Researchers caution the planets may not have oceans like those on Earth directly at the planet’s surface.

>“The temperature in Kepler-138c's and Kepler-138d’s atmospheres is likely above the boiling point of water, and we expect a thick, dense atmosphere made of steam on these planets. Only under that steam atmosphere there could potentially be liquid water at high pressure, or even water in another phase that occurs at high pressures, called a supercritical fluid," Piaulet said.

>The researchers had another surprise: they found that the two water worlds Kepler-138c and d are “twin” planets, with virtually the same size and mass, while they were previously thought to be drastically different.

Nature Astronomy, 2022. DOI 10.1038/s41550-022-01835-4

Excerpt:

>US aerospace company Boeing said it has held discussions with Emirates officials about the UAE providing an airlock module on the Lunar Gateway.

>This is an airtight room that astronauts would use to enter and exit the space station.

>John Mulholland, vice president and International Space Station programme manager at Boeing, told The National that the company was “actively working” with the UAE on the concept and design.

>The Lunar Gateway falls under Nasa’s Artemis programme, which aims to put humans back on the Moon’s surface this decade.

>“One of the things that the UAE is working on is the evaluation of whether they are going to put up an airlock module on the Gateway, which would be outstanding,” said Mr Mulholland at the Abu Dhabi Space Debate.

> 

>There is no agreement that has been signed between the UAE and Boeing yet on the project, and Mr Mulholland said that the country was still evaluating.

>However, Sean Fuller, international partner manager on the Gateway programme, said on Monday that an announcement would be made in a couple of months.

>He said that Nasa was in “active negotiations” with a potential new partner to contribute to an airlock module, according to a tweet by space journalist Jeff Foust.

>The UAE has been exploring ways of becoming involved in the Artemis programme.

>The Emirates is one of the signatories of the Artemis Accords, a set of US-led international agreements that outline the responsible exploration of the Moon and beyond.

Sarwat Nasir, 13 December 2022, The National (International Media Investments)

>DoomGoober

>Odd that the article says propioception is unconscious. Other papers say there are both conscious and unconscious forms of proprioception:

>https://pubmed.ncbi.nlm.nih.gov/18851800/

>J Surg Orthop Adv. 2008 Fall.

An excerpt from Somatosensory 1, last revised December 2013:

>UNCONSCIOUS "PROPRIOCEPTION":

>The sensory information discussed above, which is useful for consciousness, is also useful for unconscious functional control of movement. Therefore:

>• The primary afferent axon, upon entering the spinal cord, will have branches (collaterals) to share the sensory signal with "local reflex" neurons, and

>• To share the signal with the cerebellum (works at unconscious level) by a synapse with spinal cord neurons, whose axons form spinocerebellar tracts.

>http://anat403.class.uic.edu/Lectures/lecture6_09.htm

Excerpt:

>Sight, hearing, smell, taste, touch: We’re all familiar with the five senses that allow us to experience our surroundings.

>Equally important but much less well known is the sixth sense: “Its job is to collect information from the muscles and joints about our movements, our posture and our position in space, and then pass that on to our central nervous system”, says Dr. Niccolò Zampieri, head of the Development and Function of Neural Circuits Lab at the Max Delbrück Center in Berlin.

>“This sense, known as proprioception, is what allows the central nervous system to send the right signals through motor neurons to muscles so that we can perform a specific movement.”

> 

>The pSN cell bodies are located in the dorsal root ganglia of the spinal cord. They are connected via long nerve fibers to the muscle spindles and Golgi tendon organs that constantly register stretch and tension in every muscle of the body. The pSN send this information to the central nervous system, where it is used to control motor neuron activity so that we can perform movements.

>Using single-cell sequencing, the team investigated which genes in the pSN of the abdominal, back and leg muscles are read and translated into RNA. “And we did find characteristic genes for the pSN connected to each muscle group,” says Dietrich. “We also showed that these genes are already active at the embryonic stage and remain active for at least a while after birth.”

>Dietrich explains that this means there are fixed genetic programs that decide whether a proprioceptor will innervate the abdominal, back or limb muscles.

Nature Communications, 2022. DOI 10.1038/s41467-022-34589-8

Excerpt:

>Rishi Sunak is set to announce a collaboration between the UK, Italy and Japan to develop a new fighter jet that uses artificial intelligence.

>The nations will develop a next generation fighter - due to enter service in the mid-2030s - that will eventually replace the Typhoon jet.

>It is hoped the new Tempest jet will carry the latest weapons.

>But building such a complex aircraft is extremely expensive - developing the F35 jet was the most expensive programme ever undertaken by the Pentagon - so Britain has been looking for partners.

>Italy was already on board, and the addition of Japan is a significant move - at a time when Britain is building closer ties with allies in the Indo-Pacific region worried about a more assertive China.

>Other countries could still join the programme. France, Germany and Spain are already working together on their own separate design - as is the United States.

Jonathan Beale, 9 December 2022.

Further reading:

>The Global Combat Air Programme (GCAP) is a new partnership and ambitious endeavour between the UK, Japan and Italy to deliver the next generation of combat air fighter jets.

>Due to take to the skies by 2035, the ambition is for this to be a next-generation jet enhanced by a network of capabilities such as uncrewed aircraft, advanced sensors, cutting-edge weapons and innovative data systems.

>The combat aircraft developed through GCAP is also expected to be compatible with other NATO partners’ fighter jets.

PM announces new international coalition to develop the next generation of combat aircraft, 9 December 2022, https://www.gov.uk/government/news/pm-announces-new-international-coalition-to-develop-the-next-generation-of-combat-aircraft

Louise Lerner, 5 December 2022.

Excerpt:

>For a long time, we didn’t know very much about the weather in the Southern Hemisphere: most of the ways we observe weather are land-based, and the Southern Hemisphere has much more ocean than the Northern Hemisphere does.

>But with the advent of satellite-based global observing in the 1980s, we could quantify just how extreme the difference was. The Southern Hemisphere has a stronger jet stream and more intense weather events.

>[The authors] used a numerical model of Earth’s climate built on the laws of physics that reproduced the observations. Then they removed different variables one at a time, and quantified each one’s impact on storminess.

> 

>The first variable they tested was topography. Large mountain ranges disrupt air flow in a way that reduces storms, and there are more mountain ranges in the Northern Hemisphere.

>The other half had to do with ocean circulation. Water moves around the globe like a very slow but powerful conveyor belt: it sinks in the Arctic, travels along the bottom of the ocean, rises near Antarctica and then flows up near the surface, carrying energy with it. This creates an energy difference between the two hemispheres.

>The Southern Hemisphere storminess changes were connected to changes in the ocean. They found a similar ocean influence is occurring in the Northern Hemisphere, but its effect is canceled out by the absorption of sunlight in the Northern Hemisphere due to the loss of sea ice and snow.

>The scientists checked and found that models used to forecast climate change as part of the Intergovernmental Panel on Climate Change assessment report were showing the same signals—increasing storminess in the Southern Hemisphere and negligible changes in the Northern—which serves as an important independent check on the accuracy of these models.

Proceedings of the National Academy of Sciences, 2022. DOI 10.1073/pnas.2123512119

November 28, 2022.

>Whatcheeria was a six-foot-long lake-dwelling creature with a salamander-like body and a long, narrow head; its fossils were discovered in a limestone quarry near the town of What Cheer, Iowa.

>There are around 350 Whatcheeria specimens, ranging from single bones to complete skeletons, that have been unearthed, and every last one of them resides in the Field Museum’s collections.

>In a new study in Communications Biology, these specimens helped reveal how Whatcheeria grew big enough to menace its fishy prey: instead of growing “slow and steady” the way that many modern reptiles and amphibians do, it grew rapidly in its youth.

>Whatcheeria was a top predator. Bony grooves in its skull for sensory organs shared by fish and aquatic amphibians reveal that it lived underwater, and its sturdy leg bones could have helped it hunker down in one spot and wait for prey to swim by.

>While Whatcheeria looks like a giant salamander, it isn’t one-- it’s a “stem tetrapod,” an early four-legged critter that’s part of the lineage that eventually evolved into the four-limbed animals alive today.

> 

>“Whatcheeria is more closely related to living tetrapods like amphibians and reptiles and mammals than it is to anything else, but it falls outside of those modern groups,” says Ken Angielczyk, a curator at the Field Museum and co-author of the study. “That means that it can help us learn about how tetrapods, including us, evolved.”

>To see how Whatcheeria grew, [Ben Otoo, co-author; PhD student at the University of Chicago] and Angielczyk offered up thigh bones from nine Whatcheeria individuals ranging from juvenile to adult.

>[Lead author Megan Whitney] and her advisor, Harvard University’s Stephanie Pierce, took thin slices of bone and examined them under a microscope. When an animal is growing, it creates new layers of bone every growing season, says Otoo.

>In addition to helping give us a better sense of the evolutionary pressures on early tetrapods, the researchers say the findings are a reminder that evolution isn’t a neat stepwise process: it’s a series of experiments.

Communications Biology, 2022. DOI 10.1038/s42003-022-04079-0

Excerpt:

>In a new study published today [5 December 2022] in the European Geosciences Union journal The Cryosphere, an international team of scientists synthesized multisource data from 2001 to 2018 to explore the spatiotemporal variations of both surface and basal melt/freeze onsets and uncover the mechanism behind them.

>These findings could improve our understanding of changes in the atmosphere–ice–ocean system and the mass balance of sea ice in a changing Arctic.

>“Thinner ice thickness and thinner snow cover favors earlier basal freeze onset. The ocean plays a cross-seasonal role in regulating the growth or decay of sea ice,” explains lead author Long Lin from the Polar Research Institute of China.

> 

>The researchers found that the overall average basal freeze onset of Arctic multiyear ice was almost 3 months later than the surface.

>According to Lin, although thinner ice generally experiences a longer freezing season, the total ice growth still cannot offset the sea ice loss in summer.

>“From another point of view, the self-regulation of the Arctic sea ice-ocean system will delay the loss of Arctic sea ice.”

>These results present the first complete picture of Arctic sea ice freeze-thaw cycle, and its coupling with atmosphere atop and ocean underlying.

>It also highlights the importance of synchronous comprehensive monitoring of air-ice-ocean system, which helps explain the physical nature of the coupling process.

The Cryosphere, 2022. DOI 10.5194/tc-16-4779-2022