13,000-year-old human footprints found off Canada's Pacific coast

Photograph of track #17 beside digitally-enhanced image of same feature using the DStretch plugin for ImageJ. Note the toe impressions and arch indicating that this is a right footprint.

Human footprints found off Canada's Pacific coast may be 13,000 years old, according to a study published March 28, 2018 in the open-access journal PLOS ONE by Duncan McLaren and colleagues from the Hakai Institute and University of Victoria, Canada.

Previous research suggests that, during the last ice age (which ended around 11,700 years ago), humans moved into the Americas from Asia across what was then a land bridge to North America, eventually reaching what is now the west coast of British Columbia, Canada as well as coastal regions to the south. Along the pacific coast of Canada, much of this shoreline is today covered by dense forest and only accessible by boat, making it difficult to look for the archaeological evidence which might support this hypothesis. In this study, the research team excavated intertidal beach sediments on the shoreline of Calvert Island, British Columbia, where the sea level was two to three meters lower than it is today at the end of the last ice age.

The researchers uncovered 29 human footprints of at least three different sizes in these sediments, which radiocarbon dating estimated to be around 13,000 years old. Measurements and digital photographic analyses revealed that the footprints probably belonged to two adults and a child, all barefoot. The findings suggest that humans were present on the west coast of British Columbia about 13,000 years ago, as it emerged from the most recent ice age.

This finding adds to the growing body of evidence supporting the hypothesis that humans used a coastal route to move from Asia to North America during the last ice age. The authors suggest that further excavations with more advanced methods are likely to uncover more human footprints in the area and would help to piece together the patterns of early human settlement on the coast of North America.

Read more at Science Daily

Here’s the Actual Physics of Why Knuckles ‘Crack’

Bored and anxious humans have long ‘cracked’ their knuckles. But only in the past 60 years have scientists put serious thought into the physics of knuckle-cracking. The reigning theory, proposed in 1971, was that the sharp popping sound was caused by the collapse of small cavitation bubbles in the metacarpophalangeal (MCP) joints, the third knuckle down from the tips of your fingers.

But a 2015 paper cast doubt on the bubble-collapse theory, using real-time MRI imaging to argue that the creation of cavitation bubbles, not their collapse, was the true cause of the trademark cracking sound.

Now a team of French scientists believe they’ve restored the reputation of the original bubble-collapse theory by using mathematical modeling to prove that only a rapidly collapsing cavitation bubble could generate acoustic waves powerful enough to produce the classic pop, according to a article published in the journal Scientific Reports.

Abdul Barakat, co-author of the paper, is a professor of biodynamics at the Ecole Polytechnique where he specializes in modeling cardiovascular mechanics to better understand heart disease. It was one of his master’s students, first author V. Chadran Suja, who came up with the idea of modeling the unsolved mystery of knuckle-cracking.

Barakat told Seeker that it’s the motion of separating the knuckles in the MCP joint that creates the cavitation bubbles, tiny cavities or "voids" of gas in the joint's synovial fluid.

“If you have two surfaces that are separated by a viscous fluid and you pull these surfaces apart rapidly, you depressurize the fluid in between the surfaces,” explained Barakat. “That sudden decrease in pressure can make it so that dissolved gases in the fluid can nucleate into bubbles.”

The person cracking their knuckles doesn’t actually “pop” the cavitation bubbles by manipulating the joint. Instead, the unstable bubbles collapse on their own accord almost instantly, generating pressure waves that translate into sound.

One of the gripes from the 2015 paper was that the fraction of a second that it takes for the bubbles to fully collapse is too slow to produce the popping sound quickly enough. What Barakat and Suja’s mathematical models show is  that even a partial collapse of a bubble was sufficient to generate the pressure waves, matching the speed and intensity of real-world cracks.

The French researchers chose mathematical modeling over the imaging technique used in the 2015 paper, which attempted to record MRI scans of internal processes in real time. Barakat and Suja believe that the imaging technique, called cineradiography, hasn’t yet achieved the necessary resolution (1,200 frames per second) that is necessary to see bubble collapses in action. The frame rate of the 2015 paper, for example, was only 3.2 frames per second.

Instead, Barakat and Suja designed a two-dimensional mathematical model of the MCP joint to test the effects of different variables on the sound produced by collapsing cavitation bubbles, including the shape and geometry of the MCP joint, the force and speed used to pop the knuckles, and the viscosity of the joint fluid, which changes with age.

What they found was that the distance separating the knuckles was one critical variable. Knuckles that are closer together in a resting position produce bigger bubbles when separated during the cracking motion. Which might explain why some people have a harder time cracking their knuckles — their joints might simply be too wide.

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This ‘See-Through Galaxy’ Far, Far Away Contains Virtually No Dark Matter

A Hubble Space Telescope image of the galaxy NGC1052-DF2. Distant galaxies are visible through DF2 due to its lack of stars and “ghostly” nature.

Astronomers have found a perplexing galaxy that appears to be nearly devoid of dark matter. Since the prevailing notion is that dark matter is essential for galaxy formation, this new galaxy — called NGC1052-DF2, or DF2 for short — is a bit of a mystery.

“This galaxy is befuddling us,” astronomer Roberto Abraham told Seeker. “It’s exactly the opposite of what we expected. DF2 challenges us to explore that there may be more than one way to form a galaxy.”

Abraham is a professor at the University of Toronto and co-author on a new paper in the research journal Nature describing DF2.

In addition to the lack of dark matter, DF2 has several other peculiarities. While it is roughly the size of our Milky Way galaxy, it contains only one two-hundredth the number of stars. It has no dense, central region and no black hole. It doesn’t have spiral arms or a disk, and is more like a “blob” of stars.

DF2 also lacks the amount of gas and dust prevalent in other galaxies. An image of DF2 taken by the Hubble Space Telescope shows the wispy galaxy, where other bright objects including a distant spiral galaxy located behind it are clearly visible.

“I spent an hour just staring at the Hubble image,” lead author Pieter van Dokkum from Yale University said in a statement. “This thing is astonishing: a gigantic blob that you can look through. It’s so sparse that you see all of the galaxies behind it. It is literally a see-through galaxy.”

Van Dokkum, Abraham, and their colleagues determined the lack of dark matter by measuring the velocity of clusters of stars called globular clusters within DF2 and found they were moving slower than expected. They then calculated the galaxy’s mass and determined that the visible stars, gas and dust in DF2 accounted for most of the mass and that there was only one four-hundredth the amount of dark matter expected. Follow-up observations with Hubble confirmed their findings.

DF2 is one of a recently discovered class of galaxies called Ultra Diffuse Galaxies (UDGs). These galaxies have been described as fluffy or wispy, almost like globular clusters but without the density of stars.

Abraham and van Dokkum published the first paper about UDGs in 2015 after finding a number of these faint, wispy galaxies in the Coma Cluster, which is a dense, active region of space about 300 million light-years from Earth. It is filled bright galaxies of all shapes and sizes and lots dark matter, but yet these faint galaxies were sprinkled throughout.

Abraham explained he and van Dokkum had built a special telescope called the Dragonfly Array that looks specifically for very faint astronomical objects. It is a multi-lens array that uses commercially available telephoto lenses with specially-coated optical glass that reduces scattered light. It turns out, it was the perfect instrument for finding UDGs. 

“Astronomers have been finding isolated example of objects like this for over 30 years,” Abraham said. “But they’ve all been one-offs, or an obscure galaxy in a larger survey and they would be really rare. But then when Pieter and I built the Dragonfly Array which optimizes the detection of these low surface brightness objects, suddenly these things have been popping up like firecrackers everywhere.”

Other astronomers started looking at archival data for UDGs and have been finding several of these objects which had previously been dismissed as image artifacts or “ghost” images.

In the only Dragonfly Array image of the Coma Cluster from 2015, the team found about 50 UDGs — Milky Way-size objects that were extremely faint. Abraham said the various ideas for what UDGs are range from “failed galaxies” that ran out of gas to normal galaxies that got “knocked around so much inside the Coma cluster that they puffed up” to pieces of other galaxies that were pulled off during galaxy mergers.

“What is really emerging now is the race to understand what UDGs are,” Abraham told Seeker. “There have been two camps of trying to model these things, where one idea is it would take a lot of dark matter to create them and the other where there is just a regular amount of dark matter. But what wasn’t considered was that something would pop up that didn’t have any dark matter.”

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Earth Likely Had Water Prior to Moon-Forming Collision

Most of our planet’s water has been present since very early on, even before a giant impact from a Mars-sized object that created the moon. Despite that incredibly cataclysmic event, Earth was able to retain its water, according to a new study published in the journal Science Advances. The study authors examined lunar rocks brought back from all six of the Apollo moon landings as well as volcanic rocks from Earth’s oceans.

“Because water is such a vital ingredient for life, we rightly see it as precious,” said Richard Greenwood of Open University, a distance learning and research university located in England. “Our research shows that water is also extremely resilient and can survive an event as catastrophic as two planets colliding.”

There has long been a debate over how — and when — Earth obtained the water that is ubiquitous on our world today. While water molecules were part of the cloud of gas and dust that coalesced into our solar system 4.6 billion years ago, Earth’s early history included scorching temperatures and little-to-no atmosphere, so it was thought that any water on the planet’s surface would likely have evaporated.

There is also the prevailing theory that the moon was formed from a cataclysmic collision between proto-Earth and a solid impactor about 100 million years after our solar system’s formation. This giant impact, some scientists have proposed, surely would have blasted Earth’s water away.

That led many scientists to suggest that water would have been introduced on Earth at a later time, when it was pummeled by comets and asteroids during the Late Heavy Bombardment period, 4.1 to 3.8 billion years ago. Several studies suggest that these objects could have readily supplied the amount of water that is present on Earth today.

One sticking point for the giant impact theory, however, is planets in our solar system have unique chemical makeups. Earth and our moon appear similar when it comes to versions of elements called isotopes — specifically different isotopes of oxygen. A previous study discovered, though, that some rocks from the Apollo missions contained slightly more oxygen-17 than oxygen-16 when compared to Earth rocks. That indicated that the moon might have been primarily formed from the impactor rather than the proto-Earth.

But the new study not only supports the giant impact theory of the moon’s formation, it says Earth’s water could have survived such an event. The study also clarifies differences and similarities between the Earth and the moon.

Greenwood and his colleagues compared the oxygen composition from both Earth rocks and lunar samples brought back by the Apollo astronauts. In analyzing the oxygen-isotope compositions in both sets of samples, they showed a very small 3 to 4 parts per million difference between the two. There was “no significant difference” between the lunar samples and Earth samples in the amount of olivine, a common mineral in Earth's subsurface.

According to the authors, these findings are consistent with high-energy impact simulations that confirm an almost complete “mixing” of the proto-Earth and the impactor, as well as retention of a large amount of water on Earth, as much as 70-95 percent.

“On the basis of this assumption, our data indicates that post-giant impact additions to the Earth could have contributed between 5 and 30 percent of Earth’s water, depending on global water estimates,” the team wrote. “Consequently, our data indicate that the main fraction of Earth’s water was accreted before the giant impact and not later, as often proposed.”

Read more at Seeker

Northerners have always been hardy!

Excavating the central platform.

Pioneering early people who lived at the end of the last ice age actually carried on with life as usual despite plummeting temperatures, a study at a world-famous archaeological site in North Yorkshire suggests.

Leading researchers, based at Royal Holloway, University of London, and the University of York, found that a dramatic climate event with a sudden drop in average temperatures, severe enough to halt the development of woodland, had no substantial impact on human activity at Star Carr -- a middle Stone Age archaeological site dating to around 9,000 BC.

The study sheds new light on significant debate about the sensitivity of hunter-gatherer societies to environmental change.

The prehistoric community, who persevered through the cold snap that would last more than 100 years, left a plethora of worked wood, animal bones, antler headdresses and flint blades buried in layers of mud as evidence of their continued productivity and endurance.

Simon Blockley, Professor of Quaternary Science at Royal Holloway, said: "It has been argued that abrupt climatic events may have caused a crash in Mesolithic populations in Northern Britain, but our study reveals, that at least in the case of the pioneering colonisers at Star Carr, early communities were able to cope with extreme and persistent climate events.

"We found people were in fact far more affected by smaller, localised changes to their environment -- Star Carr was once the site of an extensive lake and people lived around its edge.

"Over time the lake gradually became shallower and boggier, turning into fenland which eventually forced settlers to abandon the area."

The early Holocene, the current geological epoch which started some 11,500 years ago when the glaciers began to retreat, was dominated by climatic instability characterised by extreme weather events triggered by ice-ocean interaction during the final wastage of the northern hemisphere ice sheets.

The rich archaeological record at Star Carr gave the researchers the rare opportunity to directly compare the palaeoclimate record with evidence of human activity through time in the same location.

The researchers examined human activity by looking at archaeological remains recovered from layers of wetland deposits at the edge of the extensive former lake basin in the Vale of Pickering.

They found evidence of houses, large wooden platforms built on the lake edge and large quantities of artefacts and bones preserved in the lake muds and these were radiocarbon dated. Pollen, macrofossils and isotopes taken from lake sediment cores allowed the researchers to build a high-resolution picture of the climate of the area over thousands of years.

The team identified two episodes of extreme cooling which saw average temperatures drop by more than 3 degrees in the space of a decade. The first of these events occurred very early after humans began to return to the area after the last ice age.

The evidence indicates that these conditions may have slowed down the progress and activity of a community in the nascent stages. However, the second of these events, which occurred later when the community was more established, appears to have had very little impact.

Professor Nicky Milner, senior author based at the University of York, added: "Perhaps the later, more established community at Star Carr were buffered from the effects of the second extreme cooling event -- which is likely to have caused exceptionally harsh winter conditions- by their continued access to a range of resources at the site including red deer.

"We have been working at Star Carr for about 15 years and the site has produced an incredibly rare glimpse into the world of our Mesolithic ancestors who lived at the end of the ice age, about 11,000 years ago.

"Putting this archaeological data into the context of the climate and environment is very exciting and shows that we need to keep an open mind when thinking about the effects of extreme climate on early populations."

Duncan Wilson, Historic England's Chief Executive, said: "Star Carr is one of the best-known Mesolithic sites in Europe and is unique in Britain for the quantity and range of organic remains from this period.

"We have been involved with funding and supporting fieldwork at Star Carr for over a decade, and thanks to studies like these we now have a much better understanding of people's resilience in the face of climate change 11,000 years ago."

The study was conducted by Royal Holloway, University of York, University of Southampton, University of Chester, University of Manchester, Historic England, University of Stirling, University of Reading, Lancaster University, University of Oxford, , Keneperu Science Center( New Zealand) and University of Glasgow.

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Sea turtles use flippers to manipulate food

A green turtle swiping the stinging jellyfish (Cyanea barkeri) in the water column at Hook Island, Queensland, Australia, taken June 2017.

Sea turtles use their flippers to handle prey despite the limbs being evolutionarily designed for locomotion, a discovery by Monterey Bay Aquarium researchers published today in PeerJ.

The in-depth examination of the phenomenon -- Limb-use By Foraging Sea Turtles, an Evolutionary Perspective -- by authors Jessica Fujii and Dr. Kyle Van Houtan and others reveals a behavior thought to be less likely in marine tetrapods is actually widespread and that this type of exaptation of flippers may have been occurring 70 million years earlier than previously thought.

"Sea turtles don't have a developed frontal cortex, independent articulating digits or any social learning," says Van Houtan, Director of Science at Monterey Bay Aquarium. "And yet here we have them 'licking their fingers' just like a kid who does have all those tools. It shows an important aspect of evolution -- that opportunities can shape adaptations."

Lead author Jessica Fujii is part of the Aquarium's sea otter research team where she specializes in ecomorphology -- the intersection of evolution, behavior and body form. Fujii's expertise in sea otter foraging and tool use behavior has influenced her recent examination of sea turtles and how they have evolved to use their limbs in novel ways.

Analysis by Fujii and Van Houtan using crowd-sourced photos and videos finds widespread examples of behaviors such as a green turtle holding a jelly, a loggerhead rolling a scallop on the seafloor and a hawksbill pushing against a reef for leverage to rip an anemone loose.

Similar behaviors have been documented in marine mammals from walruses to seals to manatees -- but not in sea turtles. The paper shows that sea turtles are similar to the other groups in that flippers are used for a variety of foraging tasks (holding, bracing, corralling).

"Sea turtles' limbs have evolved mostly for locomotion, not for manipulating prey," Fujii says. "But that they're doing it anyway suggests that, even if it's not the most efficient or effective way, it's better than not using them at all."

The finding came as a surprise to the authors, given sea turtles' ancient lineage and the fact that the reptiles are considered to have simple brains and simple flippers. The results also offer an insight into the evolution of four-limbed ocean creatures that raises questions about which traits are learned and which are hardwired.

"We expect these things to happen with a highly intelligent, adaptive social animal," Van Houtan says. "With sea turtles, it's different; they never meet their parents," Kyle says. "They're never trained to forage by their mom. It's amazing that they're figuring out how to do this without any apprenticing, and with flippers that aren't well adapted for these tasks."

The study may also help inform the aquarium's ongoing sea otter research. How developmental biology predisposes animals to adopt dining strategies is of particular interest, given the aquarium's efforts to raise stranded sea otter pups and prepare them for a return to the wild. Rearing and releasing stranded pups contributes to the aquarium's work to recover California's threatened sea otter population.

Before they're released, ecologically naïve pups have to be taught foraging behaviors, be it for crabs or abalone, by adult female sea otters at the aquarium, which serve as surrogate mothers to the pups.

Read more at Science Daily

Newfound 'organ' had been missed by standard method for visualizing anatomy

A newfound organ, the interstitium, is seen here beneath the top layer of skin, but is also in tissue layers lining the gut, lungs, blood vessels, and muscles. The organ is a body-wide network of interconnected, fluid-filled compartments supported by a meshwork of strong, flexible proteins.

Researchers have identified a previously unknown feature of human anatomy with implications for the function of all organs, most tissues and the mechanisms of most major diseases.

Published March 27 in Scientific Reports, a new study co-led by an NYU School of Medicine pathologist reveals that layers of the body long thought to be dense, connective tissues -- below the skin's surface, lining the digestive tract, lungs and urinary systems, and surrounding arteries, veins, and the fascia between muscles -- are instead interconnected, fluid-filled compartments.

This series of spaces, supported by a meshwork of strong (collagen) and flexible (elastin) connective tissue proteins, may act like shock absorbers that keep tissues from tearing as organs, muscles, and vessels squeeze, pump, and pulse as part of daily function.

Importantly, the finding that this layer is a highway of moving fluid may explain why cancer that invades it becomes much more likely to spread. Draining into the lymphatic system, the newfound network is the source of lymph, the fluid vital to the functioning of immune cells that generate inflammation. Furthermore, the cells that reside in the space, and collagen bundles they line, change with age, and may contribute to the wrinkling of skin, the stiffening of limbs, and the progression of fibrotic, sclerotic and inflammatory diseases.

The field has long known that more than half the fluid in the body resides within cells, and about a seventh inside the heart, blood vessels, lymph nodes, and lymph vessels. The remaining fluid is "interstitial," and the current study is the first to define the interstitium as an organ in its own right, and as one of the largest of the body, say the authors.

The researchers say that no one saw these spaces before because of the medical field's dependence on the examination of fixed tissue on microscope slides, believed to offer the most accurate view of biological reality. Scientists prepare tissue this examination by treating it with chemicals, slicing it thinly, and dying it to highlight key features. The "fixing" process makes vivid details of cells and structures, but drains away any fluid. The current research team found that the removal of fluid as slides are made causes the connective protein meshwork surrounding once fluid-filled compartments to pancake, like the floors of a collapsed building.

"This fixation artifact of collapse has made a fluid-filled tissue type throughout the body appear solid in biopsy slides for decades, and our results correct for this to expand the anatomy of most tissues," says co-senior author Neil Theise, MD, professor in the Department of Pathology at NYU Langone Health. "This finding has potential to drive dramatic advances in medicine, including the possibility that the direct sampling of interstitial fluid may become a powerful diagnostic tool."

The study findings are based on newer technology called probe-based confocal laser endomicroscopy, which combines the slender camera-toting probe traditionally snaked down the throat to view the insides of organs (an endoscope) with a laser that lights up tissues, and sensors that analyze the reflected fluorescent patterns. It offers a microscopic view of living tissues instead of fixed ones.

Using this technology in the fall of 2015 at Beth Israel Medical Center, endoscopists and study co-authors David Carr-Locke, MD, and Petros Benias, MD, saw something strange while probing a patient's bile duct for cancer spread. It was a series of interconnected cavities in this submucosal tissue level that not match any known anatomy.

Faced with a mystery, the endoscopists walked the images into the office of their partnering pathologist in Theise. Strangely, when Theise made biopsy slides out of the same tissue, the reticular pattern found by endomicroscopy disappeared. The team would later confirm that very thin spaces seen in biopsy slides, traditionally dismissed as tears in the tissue, were instead the remnants of collapsed, previously fluid-filled compartments.

A New Bodily Space

For the current study, the team collected tissue specimens of bile ducts during twelve cancer surgeries that were removing the pancreas and the bile duct. Minutes prior to clamping off blood flow to the target tissue, patients underwent confocal microscopy for live tissue imaging.

Once the team recognized this new space in images of bile ducts, they quickly recognized it throughout the body, wherever tissues moved or were compressed by force. The cells lining the space are also unusual, perhaps responsible for creating the supporting collagen bundles around them, say the authors. The cells may also be mesenchymal stem cells, says Theise, which are known to be capable of contributing to the formation of scar tissue seen in inflammatory diseases. Lastly, the protein bundles seen in the space are likely to generate electrical current as they bend with the movements of organs and muscles, and may play a role in techniques like acupuncture, he says.

Read more at Science Daily

Secrets of famous Neanderthal skeleton La Ferrassie 1 revealed

An international team of researchers, led by Dr. Asier Gomez-Olivencia of the University of the Basque Country (UPV/EHU) and including Binghamton University anthropologist Rolf Quam, has provided new insights on one of the most famous Neandertal skeletons, discovered over 100 years ago: La Ferrassie 1. Nearly all of the fractures were made post-mortem.

An international team of researchers, led by Dr. Asier Gomez-Olivencia of the University of the Basque Country (UPV/EHU) and including Binghamton University anthropologist Rolf Quam, has provided new insights on one of the most famous Neanderthal skeletons, discovered over 100 years ago: La Ferrassie 1.

"New technological approaches are allowing anthropologists to peer even deeper into the bones of our ancestors," said Quam. "In the case of La Ferrassie 1, these approaches have made it possible to identify new fossil remains and pathological conditions of the original skeleton as well as confirm that this individual was deliberately buried.

The adult male La Ferrassie 1 Neanderthal skeleton was found in 1909 in a French cave site, along with the remains of an adult woman and several Neanderthal children. All of the skeletons were interpreted as representing intentional burials, and the finds sparked much public interest at the time regarding just how human-like the Neanderthals were. The La Ferrassie 1 skeleton, in particular, has been highly influential in Neanderthal studies since its discovery.

La Ferrassie 1 was an old man (likely over 50 years old) who suffered various broken bones during his lifetime and had ongoing respiratory issues when he died. Soon after, he was buried by other members of his group in the La Ferrassie rockshelter, which was repeatedly occupied by Neanderthals during millennia. The skeleton was found in a burial pit and has been dated to between 40,000 and 54,000 years. This skeleton is one of the most important Neanderthal individuals both for its completeness and due to the important role it has played historically in the interpretation of Neanderthal anatomy and lifeways.

Now, researchers have applied some of the latest technological approaches to reveal long-held secrets in the skeleton of this iconic individual. The bones were subjected to high resolution microCT scanning to study the internal anatomy of the skull and several of the bones. The middle ear bones (malleus, incus and stapes) were identified in the scans, held in place inside the skull by sediments from the La Ferrassie cave floor. These are the smallest bones in the human body and are often not preserved in archaeological skeletons, but it was possible to extract 3D virtual models of the bones for analysis. The ear ossicles are complete and help provide a better understanding of the range of variation of this anatomical region in Neanderthals. Several pathological conditions were also identified in the skeleton, including a fracture in the collar bone (clavicle), arthritis of the spine and mild scoliosis. Researchers also examined the archaeological materials from the original excavations and identified several new fragments of vertebrae and ribs of La Ferrassie 1.

Study of the original skeleton and analysis of the fracture pattern of the cranium and long bones relying on modern forensic criteria confirmed that nearly all of the fractures were post-mortem (i.e. after death), when the bones lost collagen and were fractured in situ due to the weight of the overlying sediments. Nevertheless, the anatomical connection between the bones was not affected, confirming the original observations made over a century ago by their discoverers, that the La Ferrassie 1 individual was deliberately buried by other members of their social group.

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Newly-discovered planet is hot, metallic and dense as Mercury

Dr. David Armstrong from the University of Warwick's Astronomy and Astrophysics Group.

A hot, metallic, Earth-sized planet with a density similar to Mercury -- situated 339 light years away -- has been detected and characterised by a global team of astronomers, including the University of Warwick.

Named K2-229b, the planet is almost 20% larger than Earth but has a mass which is over two-and-a-half times greater -and reaches a dayside temperature of over 2000°C (2330 Kelvin).

It finds itself very close to its host star (0.012 AU, around a hundredth of the distance between Earth and the Sun), which itself is a medium-sized active K dwarf in the Virgo Constellation. K2-229b orbits this star every fourteen hours.

Led overall by researchers at Aix-Marseille Université in France, Dr David Armstrong and colleagues at the University of Warwick's Astronomy and Astrophysics Group independently detected the planet in the first instance, alongside researchers at the Universidade do Porto.

Using the K2 telescope, Dr Armstrong and colleagues employed the Doppler spectroscopy technique -- also known as the 'wobble method' to discover and characterise this faraway planet.

The astronomers knew the planet was there due to dips in the light from its host star as it orbited, periodically blocking starlight.

They then calculated the size, position and mass of K2-229b by measuring the radial velocity of the star, and finding out how much the starlight 'wobbles' during orbit, due to the gravitational tug from the planet, which changes depending on the planet's size.

Dr David Armstrong from the University of Warwick's Astronomy and Astrophysics Group, commented: "Mercury stands out from the other Solar System terrestrial planets, showing a very high fraction of iron and implying it formed in a different way. We were surprised to see an exoplanet with the same high density, showing that Mercury-like planets are perhaps not as rare as we thought.

"Interestingly K2-229b is also the innermost planet in a system of at least 3 planets, though all three orbit much closer to their star than Mercury. More discoveries like this will help us shed light on the formation of these unusual planets, as well as Mercury itself."

The dense, metallic nature of K2-229b has numerous potential origins, and one hypothesis is that its atmosphere might have been eroded by intense stellar wind and flares, as the planet is so close to its star.

Another possibility is that K2-229b was formed after a huge impact between two giant astronomical bodies in space billions of years ago -- much like the theory that the Moon was formed after Earth collided with a body the size of Mars.

Discovering details about far-flung planets across the universe gives us more clues as to how planets in our own solar system formed. As K2-229b is similar to Mercury, knowing more about the former can potentially reveal more about the latter.

Read more at Science Daily

Understanding the strange properties of water

A clathrate ice, with oxygens represented as spheres, and hydrogen-bonds as lines. The work has shown how complex crystalline structures emerge as a result of water's interactions.

The properties of water have fascinated scientists for centuries, but yet its unique behaviour remains a mystery.

Published this week in the journal Proceedings of the National Academy of Sciences of the United States of America, a collaboration between the Universities of Bristol and Tokyo has attempted a novel route to understand what makes a liquid behave like water.

When compared to an ordinary liquid, water displays a vast array of anomalies. Common examples include the fact that liquid water expands on cooling below 4 C, which is responsible for lakes freezing from the top rather than the bottom.

In addition, the fact that water becomes less viscous when compressed, or its unusually high surface tension, allows insects to walk on water's surface.

These and many other anomalies are of fundamental importance in countless natural and technological processes, such as the Earth's climate, and the possibility of life itself. From an anthropic viewpoint, it is like the water molecule was fine-tuned to have such unique properties.

Starting from the observation that the properties of water seem to appear fine-tuned, a collaboration between Dr John Russo from the University of Bristol's School of Mathematics and Professor Hajime Tanaka from the University of Tokyo, harnessed the power of powerful supercomputers, using computational models to slowly "untune" water's interactions.

This showed how the anomalous properties of water can be changed and eventually reduced to those of a simple liquid. For example, instead of floating on water, the density of ice can be changed continuously until it sinks, and the same can be done with all water anomalies.

Dr Russo said: "With this procedure, we have found that what makes water behave anomalously is the presence of a particular arrangement of the water's molecules, such as the tetrahedral arrangement, where a water molecule is hydrogen-bonded to four molecules located on the vertices of a tetrahedron.

"Four of such tetrahedral arrangements can organise themselves in such a way that they share a common water molecule at the centre without overlapping.

"It is the presence of this highly ordered arrangement of water molecules, mixed with other disordered arrangements that gives water its peculiar properties.

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Chance is a factor in the survival of species

The beautiful demoiselle (Calopteryx virgo).

In a major study, biologists at Lund University in Sweden have studied the role of chance in whether a species survives or dies out locally. One possible consequence according to the researchers, is that although conservation initiatives can save endangered species, sometimes chance can override such efforts.

Species that differ considerably in their ecology rarely have problems living in close proximity as they do no compete for the same natural resources. When, however, two similar species live side by side and utilize the same food, habitat and other resources, this often leads to one of the species outcompeting the other, according to traditional ecological theory.

The role of chance as a contributing mechanism whether species dies out locally is not near as well investigated as is competition, and limited empirical data is available. The recent study is one of the most extensive to date, and is based on experiments and computer simulations combined with field studies.

The results show that chance has a certain significance, and that it is not possible in advance to say which of two co-existing species will die out locally.

The researchers have also studied a factor that counteracts the role of chance, known as negative frequency-dependence. . The mechanism can be described as an elastic band that is stretched out, but pulls back when a species becomes rare. This is because the few remaining individuals in the rare species gain some minority advantages, such as reduced competition or aggression from other individuals. The effect is that the rare species becomes more common again.

"Sometimes the elastic band doesn't work or pulls back too late. Then the species dies out locally," explains Erik Svensson, biologist at Lund University.

Conservation initiatives can sometimes help to save species and thereby maintain local biodiversity.

"Such efforts are definitely not futile. But the world is never totally predictable and our study shows that chance plays some role for whether a species survives locally or not. Perhaps we humans have less power than we think," he concludes.

From Science Daily

Parts of the Amazon thought uninhabited were actually home to up to a million people

This is an aerial photo of one of the structures at Jacó Sá site.

Parts of the Amazon previously thought to have been almost uninhabited were really home to thriving populations of up to a million people, new research shows.

Archaeologists have uncovered evidence that there were hundreds of villages in the rainforest away from major rivers, and they were home to different communities speaking varied languages who had an impact on the environment around them.

Huge parts of the Amazon are still unexplored by archaeologists, particularly areas away from major rivers. People had assumed ancient communities had preferred to live near these waterways, but the new evidence shows this was not the case.

The discovery fills a major gap in the history of the Amazon, and provides further evidence that the rainforest -- once thought to be untouched by human farming or occupation -- has in fact been heavily influenced by those who lived in it.

Archaeologists from the University of Exeter found the remains of fortified villages and mysterious earthworks called geoglyphs -- human-made ditches with strange square, circular or hexagonal shapes. Experts still don't know the purpose of these earthworks, as some show no evidence of being occupied. It is possible they were used as part of ceremonial rituals.

Archaeologists uncovered the remains in the current Brazillian state of Mato Grosso. By analysing charcoal remains and excavated pottery they have found a 1,800 km stretch of southern Amazonia was continuously occupied from 1250 until 1500 by people living in fortified villages. The experts estimate that there would have been between 1,000 and 1,500 enclosed villages, and two-thirds of these sites are yet to be found.

The new study shows there are an estimated 1,300 geoglyphs across 400,000km2 of Southern Amazonia, with 81 found in the area surveyed as part of this research. Villages are often found nearby, or inside the geoglyphs. They are connected through a network of causeways and some have been elaborately constructed over many years.

The earthworks were probably made during seasonal droughts, which allowed forests to be cleared. Drier areas still had fertile soils, where farmers would have been able to grow crops and fruit trees like Brazil nuts.

Dr Jonas Gregorio de Souza, from the University of Exeter's Department of Archaeology, a member of the research team said: "There is a common misconception that the Amazon is an untouched landscape, home to scattered, nomadic communities. This is not the case. We have found that some populations away from the major rivers are much larger than previously thought, and these people had an impact on the environment which we can still find today.

"The Amazon is crucial to regulating the Earth's climate, and knowing more about its history will help everyone make informed decisions about how it should be cared for in the future."

Professor José Iriarte, from the University of Exeter, another member of the research team, said: "We are so excited to have found such a wealth of evidence. Most of the Amazon hasn't been excavated yet, but studies such as ours mean we are gradually piecing together more and more information about the history of the largest rainforest on the planet.

Read more at Science Daily

What interstellar visitor 'Oumuamua can teach us

An illustration of 'Oumuamua, the first object we've ever seen pass through our own solar system that has interstellar origins.

The first interstellar object ever seen in our solar system, named 'Oumuamua, is giving scientists a fresh perspective on the development of planetary systems. A new study by a team including astrophysicists at NASA's Goddard Space Flight Center in Greenbelt, Maryland, calculated how this visitor from outside our solar system fits into what we know about how planets, asteroids and comets form.

On Oct. 19, 2017, astronomers working with the NASA-funded Panoramic Survey Telescope and Rapid Response System (Pan-STARRS1) at the University of Hawaii spotted an object zipping through our solar system at a very high speed. Scientists at the Minor Planet Center, funded by NASA's Near-Earth Object Observations Program, confirmed it was the first object of interstellar origin that we've seen. The team dubbed it 'Oumuamua (pronounced oh-MOO-ah-MOO-ah), which means "a messenger from afar arriving first" in Hawaiian -- and it's already living up to its name.

"This object was likely ejected from a distant star system," said Elisa Quintana, an astrophysicist at Goddard. "What's interesting is that just this one object flying by so quickly can help us constrain some of our planet formation models."

On Sept. 19, 'Oumuamua sped past the Sun at about 196,000 mph (315,400 km/h), fast enough to escape the Sun's gravitational pull and break free of the solar system, never to return. Usually, an object traveling at a similar speed would be a comet falling sunward from the outer solar system. Comets are icy objects that range between house-sized to many miles across. But they usually shed gas and dust as they approach the Sun and warm up. 'Oumuamua didn't. Some scientists interpreted this to mean that 'Oumuamua was a dry asteroid.

Planets and planetesimals, smaller objects that include comets and asteroids, condense out of disks of dust, gas and ice around young stars. Smaller objects that form closer to their stars are too hot to have stable surface ice and become asteroids. Those that form farther away use ice as a building block and become comets. The region where asteroids develop is relatively small.

"The total real estate that's hot enough for that is almost zero," said lead author Sean Raymond, an astrophysicist at the French National Center for Scientific Research and the University of Bordeaux. "It's these tiny little circular regions around stars. It's harder for that stuff to get ejected because it's more gravitationally bound to the star. It's hard to imagine how 'Oumuamua could have gotten kicked out of its system if it started off as an asteroid."

The distance from a star beyond which water stays ice, even if it's exposed to sunlight, is called the snow line or ice line. In our own solar system, for example, objects that developed within three times the distance between the Sun and Earth would have been so hot that they lost all their water. That snow line contracted a little as the Sun shrank and cooled over time, but our main belt asteroids are located within or near our snow line -- close enough to the Sun that it would be difficult to be ejected.

"If we understand planet formation correctly, ejected material like 'Oumuamua should be predominantly icy," said Thomas Barclay, an astrophysicist at Goddard and the University of Maryland, Baltimore County. "If we see populations of these objects that are predominantly rocky, it tells us we've got something wrong in our models."

Scientists suspect most ejected planetesimals come from systems with giant gas planets. The gravitational pull of these massive planets can fling objects out of their system and into interstellar space. Systems with giant planets in unstable orbits are the most efficient at ejecting these smaller bodies because as the giants shift around, they come into contact with more material. Systems that do not form giant planets rarely eject material.

Using simulations from previous research, Raymond and colleagues showed that a small percentage of objects get so close to gas giants as they're ejected that they should be torn into pieces. The researchers believe the strong gravitational stretching that occurs in these scenarios could explain 'Oumuamua's long, thin cigar-like shape.

The researchers calculated the number of interstellar objects we should see, based on estimates that a star system likely ejects a couple of Earth-masses of material during planet formation. They estimated that a few large planetesimals will hold most of that mass but will be outnumbered by smaller fragments like 'Oumuamua. The results were published March 27 in the journal Monthly Notices of the Royal Astronomical Society.

The findings have already been partially confirmed by observations of the object's color. Other studies have also noted that star systems like our own would be more likely to eject comets than asteroids. Future observatories like the National Science Foundation-funded Large Synoptic Survey Telescope could help scientists spot more of these objects and improve our statistical understanding of planet and planetesimal formation -- even beyond our solar system.

Read more at Science Daily

Here’s Why Marine Mammals Are Big — But Not Too Big

A blue whale in the waters off the coast of Colombo, Sri Lanka, April 2015.

The blue whale (Balaenoptera musculus) is the largest animal ever to have lived on Earth. Growing up to 108 feet long, it may exceed the length of an NBA basketball court (94 feet). Its weight has been estimated to be as high as 441,000 pounds, which is almost as much as the entire Statue of Liberty (450,000 lbs.).

Many other marine mammals, such as orcas and walruses, are not lightweights either. Scientists over the years have speculated that pressure on body size is more relaxed in water, possibly because the ability to float removes the necessity of supporting body weight on limbs.

New research counters that theory, though, concluding instead that mammal growth is actually more constrained in water than on land. The findings, reported in the Proceedings of the National Academy of Sciences, show that aquatic mammal size is bounded at the small end by the need to retain heat and at the large end by challenges associated with food acquisition.

"We went in just looking to statistically show that aquatic mammals are larger than we would expect by chance," lead author William Gearty, a graduate student at Stanford School of Earth, Energy, and Environmental Sciences (Stanford Earth), told Seeker.

"While we did find that," he added, "we also came away with surprising new knowledge that these mammals are actually under really strong evolutionary pressures, much stronger than those on land, which goes against the expectations of many hypotheses regarding why these animals have gotten so big."

He explained that there are fewer orders of magnitude between the smallest and largest aquatic mammals than there are between the smallest and largest terrestrial mammals.

The smallest known marine mammal is the marine otter (Lontra felina), which weighs up to 13 lbs. The smallest terrestrial mammal by mass is the Etruscan shrew (Suncus etruscus), which weighs only around 0.063 ounces. The largest terrestrial mammal by mass is the African bush elephant (Loxodonta africana), with males weighing around 13,000 lbs. and females weighing about half that much.

Marine otter

Gearty and co-author Jonathan Payne, a professor of geological sciences at Stanford Earth, compiled body masses for 3,859 living and 2,999 fossil mammal species from existing data sets. They analyzed the data — which includes about 70 percent of all known living species and 25 percent of extinct species — with models developed in collaboration with co-author Craig McClain of the Louisiana Universities Marine Consortium.

All aquatic mammals appear to have had terrestrial ancestors. Seals and sea lions are closely related to dogs, for example, while manatees share ancestry with elephants. Whales and dolphins are related to hippos and to other hoofed mammals.

The researchers found that when the land-based ancestors of marine mammals gradually adapted to aquatic life, they evolved very quickly toward larger sizes and converged at around 1,000 lbs.

"Since mammals are warm-blooded, we need to maintain relatively high internal body temperatures," Gearty said. "Once mammals enter the water, this becomes an even harder process, and the only way to counteract this pressure is to get larger to reduce the relative amount of energy you lose to the water around you."

Marine otter ancestors evolved for an aquatic lifestyle more recently, so they have not yet followed that trend. This could also be because otters still live much of their lives on land.

The largest marine mammals, blue whales, are also clearly an exception to the 1,000-pound trend.

"The tricky thing about an optimum is that, if every species tried to be that size they would all be competing with one another, and that's not good for anyone," Gearty said. "Also, the differences in energy conservation between 100 kilograms (221 lbs.), 500 kg (1,102 lbs.), and 1,000 kg (2,205 lbs.) aren't make-or-break."

"As long as you aren't losing energy, you are doing just fine," he continued. "So, if you can find some niche that lets you survive at a slightly different size, it's better to take advantage of that than try to compete with the other species that are at the optimum."

Blue whales possess a filter-feeder system known as baleen. During peak consumption periods, these marine giants may consume thousands of pounds of krill and copepods, which are a type of small aquatic crustacean.

As large as the blue whale is, the models created by the scientists show that this marine mammal could have an even larger optimal body size. Human-related pressures could be preventing the blue whale from evolving into this bigger size.
McClain told Seeker, "We know that humans have a tremendous impact on the body-size distributions on both land and in the oceans."

He explained that an earlier study came to the same conclusion. Still other research has shown that fishing has resulted in a reduction in overall fish sizes. A prior study led by McClain found that decreases in whale sizes through time have occurred due to whaling.

Other factors affect animal body sizes. During the Dinosaur Era, millions of years before our species emerged, many terrestrial mammals often grew to enormous sizes. Tyrannosaurus rex, for example, is estimated to have grown up to 20 feet in height and to have weighed up to 20,000 lbs.

"Some large sizes were obtained because atmospheric oxygen was greater," McClain said, adding that still other large sizes were obtained because certain animals didn't have many, if any, competitors.

When non-avian dinosaurs and numerous other animals went extinct around 66 million years ago, surviving mammals evolved to fill the ecosystem voids. Mammals that eventually evolved into aquatic species must have been living initially along the edges of bodies of water, consuming prey like fish or marine invertebrates. Research on such a transition from land to water life was published a few years ago in the journal Science.

"Once animals get hooked on that diet, the only way to make that diet more efficient is to move into the water," Gearty said. "It's a gradual process for sure, which we see occur over millions of years in the fossil record."

He added, "While it's likely a very difficult process, mammals have made the full transition at least six times in the fossil record. All of the transitions seem to be at different times in the past, so it doesn't look like it was climate-driven."

One of the most controversial past theories for human evolution is the aquatic ape hypothesis. First proposed by marine biologist Alister Hardy (1896–1985) in 1960, AAH holds that the ancestors of modern humans were more aquatic. Even if some were, they obviously did not evolve into marine mammals.

As Gearty said, "You certainly won't see any fully aquatic humans any time soon, I can say that for certain! At least, not without a lot of technology involved. If we did want to invade the aquatic realm, it would take millions of years, a lot more hair — or blubber — and a lot more mass!"

Our species' average body size, as well as that for all other animals, could be explained by basic principles of physics and chemistry. Coming up with a mathematical equation to explain this has, however, vexed scientists for decades.

McClain said, "While the principles may be basic and the model is elegant in its simplicity, often times the simplest solutions take years to come by. Not that I want to say our work is on par with Albert Einstein's, but E=MC2 is a rather simple formula founded on basic principles, but it took years for physics to get to this point."

Read more at Seeker

Landscape ridges may hold clues about ice age and climate change

This is a photo of grassy broad-crested De Geer moraines. The crests of two moraines can be seen in this image.

Take a drive through the countryside near the New Hampshire Seacoast and you might notice a series of tiny rolling hills that look like regularly-spaced ridges. While the repeating pattern may be eye-catching for drivers, and sometimes challenging for bicycle riders, researchers at the University of New Hampshire say they may also hold answers to how glaciers helped form the current terrain and provide insight into the progression of climate change.

In their study, recently published in the Journal of Quaternary Science, the researchers used data collected from extremely high-resolution LiDAR (light and detection ranging) laser scans of the region to discover that the landscape was riddled with washboard-like ridges. To figure out how they formed, the researchers identified and mapped all the ridges they could find in the area; measured their dimensions, dug into them with an excavator and examined the way the sediment had settled into place, and used radar to "see" below the ground surface. Their research found that each ridge marks a spot where the edge of the great continental ice sheet either paused or pushed forward for long enough to pile up or bulldoze a ridge of debris in front of it. The ridges, known today as De Geer moraines, were left behind as the ice melted.

"Our evidence shows that each ridge represents one year," said Joe Licciardi, professor of Earth sciences. "If we count them up, we can figure out how long it took for the ice to retreat, or melt away from this part of New Hampshire, a little over 15,000 years ago at the end of the last ice age."

The evidence suggests that one ridge formed each year as the ice sheet oscillated back and forth, most likely by pushing forward in winter and retreating in summer. De Geer moraines only form in certain specific areas around the world and had not been recognized in New Hampshire until recently. The researchers say identifying the origin of these ridges helps determine an annual record of ice retreat across this part of New Hampshire and may hold answers to the effects of climate change.

"If you can understand what happened in the past, and how fast or slow the ice melted," said Licciardi, "it can help us understand what is going on in the present day and maybe even help us more confidently predict what might occur in the future."

The researchers say the LiDAR scans were instrumental in helping to reveal a whole new world that was not previously visible on satellite images, topographic maps, or even by simply driving around. They say the high-resolution laser helped to unveil scientific clues that were lying in plain sight and yet remarkably went unnoticed until now.

From Science Daily

Skilled female potters traveled around the Baltic nearly 5,000 years ago

Map of neolithic pottery exchange network in the Baltic Sea region.

Was it the fine pottery itself, or the artisans who made it, that moved around the Baltic Sea region during the Corded Ware Culture of late Neolithic period? Are the archaeological artefacts found in Finland imported goods or were they made out of Finnish clay by artisans who had mastered the new technology? These are the questions researchers are trying to answer in the most extensive original study of archaeological ceramics ever undertaken in the Nordic countries.

Researchers mapped the arrival routes of pottery and people representing the Corded Ware Culture complex (c. 2900-2300 BCE) into the Nordic countries by identifying the areas where the pottery was made.

Corded Ware pottery was very different from earlier Stone Age pottery. It represented a new technology and style, and as a new innovation, used crushed ceramics -- or broken pottery -- mixed in with the clay.

Eastern influences fashionable in Sweden

Finland, Estonia and Sweden had at least five different manufacturing areas for Corded Ware pottery which engaged in active pottery trade across the Baltic Sea approximately 5000 years ago. Häme in Southern Finland had a manufacturing hub of Corded Ware pottery which can be described as quasi-industrial in Neolithic terms, and spread its products along the Finnish coast and into Estonia.

Traditionally, Swedish archaeologists have assumed that Corded Ware pottery arrived in Sweden from the south. However, it now seems clear that that eastern influences were particularly fashionable during the Neolithic, and both pottery and people belonging to this culture arrived first in Eastern Sweden from Finland and Estonia. This was not a one-way one-time event: There were many active contacts in all directions across the Baltic Sea during the period, shown by the fact that pottery that was manufactured in Sweden over time turn up in Finland and Estonia.

Skilled female artisans

In traditional societies it is usually women who are in charge of the pottery craft and it is also common for women to relocate upon marriage. Corded Ware burials show that females were more likely to receive pottery as burial gifts, and analyses from European cemeteries show that the women were more likely to relocate during their lifetime.

It is likely that the first Corded Ware Culture artisans to arrive at the Fenno-Baltic and Swedish coasts were women who had learned their craft at their place of birth. They would have begun to use the clay available at their new home, but they mixed it with crushed pieces of pottery they had brought with them. Perhaps this was a way to preserve the older pottery which had been made in their previous homelands, thus maintaining a symbolic connection to their families and the members of their former communities in their everyday lives.

The study posits that skilled female artisans arrived in Sweden particularly from Estonia and Finland, as both the geochemical origin and cultural links of the imported pottery indicates a connection to the region. Cultural similarities in turn link the first Corded Ware communities in Finland and Estonia to the eastern part of the Bay of Finland, present day Russia.

The exchange network also suggests that even during the Stone Age, the Baltic Sea was less an obstacle and more a connection between communities, attaching Finland to a broader European culture.

International Stone Age phenomena are inscribed in pottery

The study examined clay pottery from 24 archaeological sites in Finland, Estonia and Sweden. The goal was to determine the geochemical composition and geological origin of Corded Ware pottery, i.e., where the clay came from.

The project involved international and cross-disciplinary cooperation between the group of archaeologists from Finland, Sweden and Estonia and material physicists. Funded by the Academy of Finland, the research project was headed by Elisabeth Holmqvist-Sipilä, who works at the University of Helsinki's archaeology laboratory.

"International prehistoric phenomena may be apparent in everyday objects, such as dishware and the old pottery fragments crushed into the clay they were made with," says Holmqvist-Sipilä.

Read more at Science Daily

Germany was covered by glaciers 450,000 years ago

The scientists recovered this 400,000-year-old stone tool ("scraper") from the gravel pit Schladebach in Saxony-Anhalt, Germany, during sampling for luminescense dating.

The timing of the Middle Pleistocene glacial-interglacial cycles and the feedback mechanisms between climatic shifts and earth-surface processes are still poorly understood. This is largely due to the fact that chronological data of sediment archives representing periglacial, but also potentially warmer climate periods, are very sparse until now.

"The Quaternary sediments in central Germany are perfect archives to understand the climate shifts that occurred in the region during the last 450,000 years," says co-author Tobias Lauer, a geochronologist at the Max Planck Institute for Evolutionary Anthropology. "This is because all sediments representing the ice advances and retreats of Scandinavian glaciers into Europe are preserved here." The sediments in the region, and especially in the area around the city Leipzig, are extremely well documented due to tens of thousands of drillings over the past few decades and open pits related to brown-coal mining.

Especially relevant are the river deposits of local rivers like the Weisse Elster and the Saale, which are preserved between the moraines of the so-called "Elsterian" and "Saalian" ice advances. "Especially the timing of the first major glaciation has been highly debated within the scientific community during the last few decades," says Lauer. "By dating the river deposits systematically we found that the first ice coverage of central Germany during the Elsterian glaciation (named after the river Elster) occurred during marine isotope stage 12, likely about 450,000 years ago, which is 100,000 years earlier than previously thought." To obtain these dates the researchers used luminescence dating, a technology that determines how long ago mineral grains were last exposed to sunlight or heat.

Tools from the Paleolithic

The river deposits also contain Lower- and Middle Paleolithic stone artefacts yielding important information on early human dispersal in central Europe. "The first traces of human Lower Paleolithic occupation in the area date back to about 400,000 years and are connected most probably to the interglacial period following the first major glaciation," says co-author Marcel Weiss, an archeologist at the Leipzig Max Planck Institute. "These traces are evidenced by more than 6,000 Lower Paleolithic stone artefacts that had been recovered from the gravel pits of Wallendorf and Schladebach in Saxony-Anhalt, Germany."

Middle Paleolithic stone artefacts from the same region are correlated with river deposits dated between 300,000 and 200,000 years ago and are associated with Neanderthals. The Pleistocene river gravel deposits from the top of the sequence in the former brown-coal mine Zwenkau, which is located south of Leipzig in Saxony, yielded the oldest Middle Paleolithic artefacts. This artefact inventory, the stone tool assemblage of "Eythra," is known for its numerous handaxes and dates back to about 280,000 years ago.

The youngest sediments from which the researchers obtained the new dates belong to the so-called Saalian glaciation (named after the river Saale). The southernmost ice advance of Scandinavian glaciers into Central Germany occurred about 150,000 years ago.

Impact on future research

"Our dates will have a major impact on the understanding of the timing of glacial cycles and climatic shifts of ice-age Europe," say the authors. "The first major glaciation had a huge impact on the environment and re-modeled the entire landscape. The newly determined ages of the Lower and Middle Paleolithic artefacts will help us in the future to reconstruct the ways in which humans populated or re-populated central Germany and central Europe following this major climatic impact."

Read more at Science Daily

Paleontologists put the bite on an ancient reptile from New England

This series of images shows the reconstruction process for the ancient reptile species Colobops noviportensis.

Scientists have identified a new species of reptile from prehistoric Connecticut and, boy, does it have a mouth on it.

Named Colobops noviportensis, the creature lived 200 million years ago and had exceptionally large jaw muscles -- setting it apart from other reptiles at the time. Even compared to the wide diversity of reptile species today, Colobops noviportensis had quite the bite.

"Colobops would have been a diminutive but plucky little beast, part of a little-known menagerie of small animals that lived among the first dinosaurs," said Bhart-Anjan Bhullar, assistant professor and assistant curator in geology and geophysics at Yale, and senior author of a new paper about the discovery in the journal Nature Communications.

"Its tiny frame hid some big secrets," Bhullar said. "Despite its lizard-like aspect, it is in fact an early branch-off of the lineage leading to dinosaurs and birds. Also, its little jaws could bite harder than anything else its size. Perhaps that big bite allowed it to feed on tough, armored prey impervious to weaker mouths."

The lead author of the paper is Adam Pritchard, a former member of Bhullar's lab who is now at the Smithsonian Institution.

Additional Yale authors of the paper are Jacques Gauthier, professor of geology and geophysics and curator of vertebrate paleontology and vertebrate zoology at the Peabody Museum; and Michael Hanson, a graduate student in geology and geophysics.

"This project was a great example of the process of science," Pritchard said. "The skull was initially discovered in the mid-1960s. In the 1990s, the skull was subject to initial study in which it was identified as a cousin of a modern lizard-like reptile called a tuatara. Our study ups the ante again, using advanced CT scanning and 3D modeling to reveal all kinds of new features of the skull. The features are very distinctive, allowing us to establish a new species."

The specimen is a quarter-sized skull discovered in Meriden, Conn., during roadwork in 1965. It has been part of the collections of the Yale Peabody Museum of Natural History for decades. The specimen's new species name derives from Novus Portus, a Latinized version of New Haven -- a reference to the New Haven Arkose geological formation.

The Yale team took a new look at the specimen. The researchers did a 3D reconstruction of the skull and discovered that it showed specialization in the jaw that was unprecedented in any other known small tetrapod, juvenile or adult.

"Comparisons with modern reptile dissections showed that it had incredibly well-developed jaw muscles for its size, suggesting an exceptional bite, even compared to the diversity of modern reptiles," Pritchard said. "It's a great illustration of the critical importance of fossils big and small for understanding the diversity of organisms."

Read more at Science Daily

Smaller and faster: The terahertz computer chip is now within reach

Following three years of extensive research, Hebrew University of Jerusalem (HU) physicist Dr. Uriel Levy and his team have created technology that will enable our computers -- and all optic communication devices -- to run 100 times faster through terahertz microchips.

Until now, two major challenges stood in the way of creating the terahertz microchip: overheating and scalability.

However, in a paper published this week in Laser and Photonics Review, Dr. Levy, head of HU's Nano-Opto Group and HU emeritus professor Joseph Shappir have shown proof of concept for an optic technology that integrates the speed of optic (light) communications with the reliability -- and manufacturing scalability -- of electronics.

Optic communications encompass all technologies that use light and transmit through fiber optic cables, such as the internet, email, text messages, phone calls, the cloud and data centers, among others. Optic communications are super fast but in microchips they become unreliable and difficult to replicate in large quanitites.

Now, by using a Metal-Oxide-Nitride-Oxide-Silicon (MONOS) structure, Levy and his team have come up with a new integrated circuit that uses flash memory technology -- the kind used in flash drives and discs-on-key -- in microchips. If successful, this technology will enable standard 8-16 gigahertz computers to run 100 times faster and will bring all optic devices closer to the holy grail of communications: the terahertz chip.

As Dr. Uriel Levy shared, "this discovery could help fill the 'THz gap' and create new and more powerful wireless devices that could transmit data at significantly higher speeds than currently possible. In the world of hi-tech advances, this is game-changing technology,"

Meir Grajower, the leading HU PhD student on the project, added, "It will now be possible to manufacture any optical device with the precision and cost-effectiveness of flash technology."

Coming soon to a chip near you…

From Science Daily

Deep impact: Deep-sea wildlife more vulnerable to extinction than first thought

We have only known about the existence of the unusual yeti crabs (Kiwaidae) -- a family of crab-like animals whose hairy claws and bodies are reminiscent of the abominable snowman -- since 2005, but already their future survival could be at risk.

New Oxford University research suggests that past environmental changes may have profoundly impacted the geographic range and species diversity of this family. The findings indicate that such animals may be more vulnerable to the effects of human resource exploitation and climate change than initially thought.

Published in PLoS ONE, the researchers report a comprehensive genetic analysis of the yeti crabs, featuring all known species for the first time and revealing insights about their evolution. All but one of the yeti crab species are found on one of the most extreme habitats on earth, deep-sea hydrothermal vents, which release boiling-hot water into the freezing waters above above them.

The research was conducted by ecologists from Oxford's Department of Zoology, Ewha Woman's University in Seoul, South Korea and additional Chinese collaborators.

The results reveal that today's yeti crabs are likely descended from a common ancestor that inhabited deep sea hydrothermal vents on mid-ocean ridges in the SE Pacific, some time around 30-40 million years ago.

By comparing the location of current yeti crab species with their history of diversification, the authors suggest that the crustaceans likely existed in large regions of mid-ocean ridge in the Eastern Pacific, but have since gone extinct in those areas.

While the reasons for this are unclear, the findings point to a specific event, when a shift in deep sea oxygen levels was triggered by climate change and changes to hydrothermal activity at mid-ocean ridges. At the same time yeti crabs appear to have changed the way they disperse their larvae between hydrothermal vents.

Christopher Roterman, co-lead author and postdoctoral researcher in of Oxford's Department of Zoology, said: 'Using these genetic techniques, our study provides the first circumstantial case for showing that hydrothermal vent species have gone extinct in large areas. The present-day locations of these animals are not necessarily indicative of their historical distribution.

'The findings have implications for our understanding of how resilient deep-sea hydrothermal vent communities might be to environmental change and the consequences of deep sea mining.'

Hydrothermal vents are just a small fraction of the deep sea environment. However, researchers are finding new species continuously and building a better picture of deep ocean life and its potential resources. Overtime these insights should help us to understand whether we can or should responsibly utilise them.

Roterman, who was also co-author of a study published last year, highlighting shocking gaps in our knowledge of deep sea environments, added: 'Our understanding of deep sea ecosystems is still very basic and we need to adopt a cautionary approach to exploitation. Before we go bulldozing in, we need to more aware of not only what lives down there, but how resilient their populations are likely to be to human activity.

Read more at Science Daily

Humankind’s Voracious Appetite for Nature Is a Threat to Our Well-Being

A golden poison frog (Phyllobates terribilis) is pictured at the Santa Fe zoo, in Medellin, Antioquia Department, Colombia, on March 21, 2018. The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) meeting, which is taking place in Medellin, opened on March 17 by stating that protecting biodiversity is "as important as fighting climate change."

Human activity has driven animals and plants into decline in every region of the world, putting our own well-being at risk by over-harvesting and polluting, a comprehensive species survey warned Friday.

Asia-Pacific fish stocks may run out by 2048 and more than half of Africa's bird and mammal species could be lost by 2100 unless drastic measures are taken, according to four comprehensive reports released at a major environmental conference in Medellin, Colombia.

Up to 90 percent of Asia-Pacific corals will suffer "severe degradation" by 2050, while in Europe and Central Asia, almost a third of known marine fish populations, and 42 percent of land animals and plants, are in decline.

In the Americas, just under a quarter of species assessed are at risk of extinction.

"This alarming trend endangers economies, livelihoods, food security, and the quality of life of people everywhere," warned the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES).

Compiled by nearly 600 scientists over three years, the reports underline that nature provides humans with food, clean water, energy, and regulates Earth's climate — just about everything we need to survive and thrive.

One of the reports found that nature's contribution to people can be in the order of thousands of dollars per hectare per year.

"We're undermining our own future well-being," IPBES chairman Robert Watson said of the findings. "Biodiversity continues to be lost across all of the regions of the globe. We're losing species, we're degrading ecosystems... if we continue 'business as usual', we will continue to lose biodiversity at increasing rates."

The president of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), British Robert Watson (3-R), speaks during a press conference in the framework of the 6th IPBES Biodiversity Summit taking place in Medellin, Antioquia Department, Colombia, on March 23, 2018.

The IPBES assessment divided the world into four regions: the Americas, Africa, Asia-Pacific, and Europe and, Central Asia — the whole planet except for the Antarctic and the open seas.

Volunteer scientists combed through some 10,000 scientific publications for the most extensive biodiversity survey since 2005.

The findings were summarized in four reports approved by 129-member IPBES's member countries in Colombia. They contain guidelines for governments to make biodiversity-friendlier policies in future.

The texts make for grim reading and come in the same week that the death of Sudan — the world's last northern white rhino male — served as a stark reminder of the stakes.

Mass extinction will continue

For the Americas, the survey warned that species populations — already 31 percent smaller than when the first European settlers arrived — will have shrunk by about 40 percent by 2050.

An estimated 500,000 square kilometers of African land is estimated to be degraded, it added.

The continent will suffer "significant" plant losses, and its lakes will be 20-30 percent less productive by 2100.

In the European Union, meanwhile, only seven percent of marine species assessed had a "favorable conservation status."

"If we continue the way we are... the sixth mass extinction, the first one ever caused by humans, will continue," Watson old AFP.

Scientists say mankind's voracious consumption of biodiversity has unleashed the first mass species die-off since the demise of the dinosaurs — only the sixth on our planet in half-a-billion years.

Demand will grow

In many places, climate change driven by burning fossil fuels for energy was worsening the loss of biodiversity, the reports found.

"Climate change for the last 30 years has been increasing its role in changing nature, changing the ability of how nature can contribute to human well-being, and it is by far the fastest-growing pressure," said Jack Rice, a co-author of the Americas report. "It is likely by 2050, a generation away, climate change will be as strong a pressure as all the ways that we have historically converted natural lands to human-dominated systems."

There are plenty of hurdles ahead.

"Economic growth is going to continue. Population growth is going to continue to 2050, therefore demand for resources will grow," said Watson.

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