Carbon reserves in Central American soils still affected by ancient Mayan deforestation

This is an ancient stone carving of the Maya God Pauahtun, taken at Copan Ruinas, Honduras.

Deforestation is suspected to have contributed to the mysterious collapse of Mayan civilization more than 1,000 years ago. A new study shows that the forest-clearing also decimated carbon reservoirs in the tropical soils of the Yucatan peninsula region long after ancient cities were abandoned and the forests grew back.

The findings, published in the journal Nature Geoscience, underscore how important soils and our treatment of them could be in determining future levels of greenhouse gases in the planet's atmosphere.

The Maya began farming around 4,000 years ago, and the spread of agriculture and building of cities eventually led to widespread deforestation and soil erosion, previous research has shown. What's most surprising in the new study is that the soils in the region haven't fully recovered as carbon sinks in over a millennium of reforestation, says McGill University geochemist Peter Douglas, lead author of the new paper.

Ecosystem 'fundamentally changed'

"When you go to this area today, much of it looks like dense, old-growth rainforest," says Douglas, an Assistant Professor of Earth and Planetary Sciences at McGill. "But when you look at soil carbon storage, it seems the ecosystem was fundamentally changed and never returned to its original state."

Soil is one of the largest storehouses of carbon on Earth, containing at least twice as much carbon as today's atmosphere. Yet scientists have very little understanding of how soil carbon reservoirs change on timescales longer than a decade or so. The new study, along with other recently published research, suggests that these reservoirs can change dramatically on timescales spanning centuries or even millennia.

To investigate these long-term effects, Douglas and his co-authors examined sediment cores extracted from the bottom of three lakes in the Maya Lowlands of southern Mexico and Guatemala. The researchers used measurements of radiocarbon, an isotope that decays with time, to determine the age of molecules called plant waxes, which are usually stored in soils for a long time because they become attached to minerals. They then compared the age of wax molecules with that of plant fossils deposited with the sediments.

The team -- which included scientists from Yale University, ETH Zurich, the University of Florida and the University of Wisconsin-Superior -- found that once the ancient Maya began deforesting the landscape, the age difference between the fossils and the plant waxes went from being very large to very small. This implies that carbon was being stored in soils for much shorter periods of time.

The project stemmed from research that Douglas had done several years ago as a PhD student at Yale, using plant-wax molecules to trace past climate change affecting the ancient Maya. At the same time, work by other researchers was indicating that these molecules were a good tracer for changes in soil-carbon reservoirs. "Putting these things together, we realized there was an important data-set here relating ancient deforestation to changes in soil carbon reservoirs," Douglas explains.

Protecting old-growth tropical forests

"This offers another reason -- adding to a long list -- to protect the remaining areas of old-growth tropical forests in the world," Douglas says. "It could also have implications for how we design things like carbon offsets, which often involve reforestation but don't fully account for the long-term storage of carbon." (Carbon offsets enable companies or individuals to offset their greenhouse-gas emissions by purchasing credits from environmental projects, such as tree-planting.)

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Ice confirmed at the moon's poles

The image shows the distribution of surface ice at the Moon's south pole (left) and north pole (right), detected by NASA's Moon Mineralogy Mapper instrument. Blue represents the ice locations, plotted over an image of the lunar surface, where the gray scale corresponds to surface temperature (darker representing colder areas and lighter shades indicating warmer zones). The ice is concentrated at the darkest and coldest locations, in the shadows of craters. This is the first time scientists have directly observed definitive evidence of water ice on the Moon's surface.

In the darkest and coldest parts of its polar regions, a team of scientists has directly observed definitive evidence of water ice on the Moon's surface. These ice deposits are patchily distributed and could possibly be ancient. At the southern pole, most of the ice is concentrated at lunar craters, while the northern pole's ice is more widely, but sparsely spread.

A team of scientists, led by Shuai Li of the University of Hawaii and Brown University and including Richard Elphic from NASA's Ames Research Center in California's Silicon Valley, used data from NASA's Moon Mineralogy Mapper (M3) instrument to identify three specific signatures that definitively prove there is water ice at the surface of the Moon.

M3, aboard the Chandrayaan-1 spacecraft, launched in 2008 by the Indian Space Research Organization, was uniquely equipped to confirm the presence of solid ice on the Moon. It collected data that not only picked up the reflective properties we'd expect from ice, but was able to directly measure the distinctive way its molecules absorb infrared light, so it can differentiate between liquid water or vapor and solid ice.

Most of the newfound water ice lies in the shadows of craters near the poles, where the warmest temperatures never reach above minus 250 degrees Fahrenheit. Because of the very small tilt of the Moon's rotation axis, sunlight never reaches these regions.

Previous observations indirectly found possible signs of surface ice at the lunar south pole, but these could have been explained by other phenomena, such as unusually reflective lunar soil.

With enough ice sitting at the surface -- within the top few millimeters -- water would possibly be accessible as a resource for future expeditions to explore and even stay on the Moon, and potentially easier to access than the water detected beneath the Moon's surface.

Learning more about this ice, how it got there, and how it interacts with the larger lunar environment will be a key mission focus for NASA and commercial partners, as we endeavor to return to and explore our closest neighbor, the Moon.

The findings were published in the Proceedings of the National Academy of Sciences on August 20, 2018.

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Massive monumental cemetery built by Eastern Africa's earliest herders discovered in Kenya

Stone pendants and earrings from the communal cemetery of Lothagam North, Kenya, built by eastern Africa's earliest herders ~5000-4300 years ago. Megaliths, stone circles, and cairns flank the 30-m platform mound; its mortuary cavity contains an estimated several hundred individuals, tightly arranged. Most burials had highly personalized ornaments. Lothagam North demonstrates monumentality may arise among dispersed, mobile groups without strong hierarchy.

An international team, including researchers at Stony Brook University and the Max Planck Institute for the Science of Human History, has found the earliest and largest monumental cemetery in eastern Africa. The Lothagam North Pillar Site was built 5,000 years ago by early pastoralists living around Lake Turkana, Kenya. This group is believed to have had an egalitarian society, without a stratified social hierarchy. Thus their construction of such a large public project contradicts long-standing narratives about early complex societies, which suggest that a stratified social structure is necessary to enable the construction of large public buildings or monuments. The study, led by Elisabeth Hildebrand, of Stony Brook University, is published in the Proceedings of the National Academy of Sciences.

The Lothagam North Pillar Site was a communal cemetery constructed and used over a period of several centuries, between about 5,000 and 4,300 years ago. Early herders built a platform approximately 30 meters in diameter and excavated a large cavity in the center to bury their dead. After the cavity was filled and capped with stones, the builders placed large, megalith pillars, some sourced from as much as a kilometer away, on top. Stone circles and cairns were added nearby. An estimated minimum of 580 individuals were densely buried within the central platform cavity of the site. Men, women, and children of different ages, from infants to the elderly, were all buried in the same area, without any particular burials being singled out with special treatment. Additionally, essentially all individuals were buried with personal ornaments and the distribution of ornaments was approximately equal throughout the cemetery. These factors indicate a relatively egalitarian society without strong social stratification.

Historically, archeologists have theorized that people built permanent monuments as reminders of shared history, ideals and culture, when they had established a settled, socially stratified agriculture society with abundant resources and strong leadership. It was believed that a political structure and the resources for specialization were prerequisites to engaging in monument building. Ancient monuments have thus previously been regarded as reliable indicators of complex societies with differentiated social classes. However, the Lothagam North cemetery was constructed by mobile pastoralists who show no evidence of a rigid social hierarchy. "This discovery challenges earlier ideas about monumentality," explains Elizabeth Sawchuk of Stony Brook University and the Max Planck Institute for the Science of Human History. "Absent other evidence, Lothagam North provides an example of monumentality that is not demonstrably linked to the emergence of hierarchy, forcing us to consider other narratives of social change."

The discovery is consistent with similar examples elsewhere in Africa and on other continents in which large, monumental structures have been built by groups thought to be egalitarian in their social organization. This research has the potential to reshape global perspectives on how -- and why -- large groups of people come together to form complex societies. In this case, it appears that Lothagam North was built during a period of profound change. Pastoralism had just been introduced to the Turkana Basin and newcomers arriving with sheep, goats, and cattle would have encountered diverse groups of fisher-hunter-gatherers already living around the lake. Additionally, newcomers and locals faced a difficult environmental situation, as annual rainfall decreased during this period and Lake Turkana shrunk by as much as fifty percent. Early herders may have constructed the cemetery as a place for people to come together to form and maintain social networks to cope with major economic and environmental change.

"The monuments may have served as a place for people to congregate, renew social ties, and reinforce community identity," states Anneke Janzen also of the Max Planck Institute for the Science of Human History. "Information exchange and interaction through shared ritual may have helped mobile herders navigate a rapidly changing physical landscape." After several centuries, pastoralism became entrenched and lake levels stabilized. It was around this time that the cemetery ceased to be used.

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Light from ancient quasars helps confirm quantum entanglement

This artist's impression of one of the most distant, oldest, brightest quasars ever seen is hidden behind dust. The quasar dates back to less than one billion years after the big bang.

Last year, physicists at MIT, the University of Vienna, and elsewhere provided strong support for quantum entanglement, the seemingly far-out idea that two particles, no matter how distant from each other in space and time, can be inextricably linked, in a way that defies the rules of classical physics.

Take, for instance, two particles sitting on opposite edges of the universe. If they are truly entangled, then according to the theory of quantum mechanics their physical properties should be related in such a way that any measurement made on one particle should instantly convey information about any future measurement outcome of the other particle -- correlations that Einstein skeptically saw as "spooky action at a distance."

In the 1960s, the physicist John Bell calculated a theoretical limit beyond which such correlations must have a quantum, rather than a classical, explanation.

But what if such correlations were the result not of quantum entanglement, but of some other hidden, classical explanation? Such "what-ifs" are known to physicists as loopholes to tests of Bell's inequality, the most stubborn of which is the "freedom-of-choice" loophole: the possibility that some hidden, classical variable may influence the measurement that an experimenter chooses to perform on an entangled particle, making the outcome look quantumly correlated when in fact it isn't.

Last February, the MIT team and their colleaguessignificantly constrainedthe freedom-of-choice loophole, by using 600-year-old starlight to decide what properties of two entangled photons to measure. Their experiment proved that, if a classical mechanism caused the correlations they observed, it would have to have been set in motion more than 600 years ago, before the stars' light was first emitted and long before the actual experiment was even conceived.

Now, in a paper published today in Physical Review Letters, the same team has vastly extended the case for quantum entanglement and further restricted the options for the freedom-of-choice loophole. The researchers used distant quasars, one of which emitted its light 7.8 billion years ago and the other 12.2 billion years ago, to determine the measurements to be made on pairs of entangled photons. They found correlations among more than 30,000 pairs of photons, to a degree that far exceeded the limit that Bell originally calculated for a classically based mechanism.

"If some conspiracy is happening to simulate quantum mechanics by a mechanism that is actually classical, that mechanism would have had to begin its operations -- somehow knowing exactly when, where, and how this experiment was going to be done -- at least 7.8 billion years ago. That seems incredibly implausible, so we have very strong evidence that quantum mechanics is the right explanation," says co-author Alan Guth, the Victor F. Weisskopf Professor of Physics at MIT.

"The Earth is about 4.5 billion years old, so any alternative mechanism -- different from quantum mechanics -- that might have produced our results by exploiting this loophole would've had to be in place long before even there was a planet Earth, let alone an MIT," adds David Kaiser, the Germeshausen Professor of the History of Science and professor of physics at MIT. "So we've pushed any alternative explanations back to very early in cosmic history."

Guth and Kaiser's co-authors include Anton Zeilinger and members of his group at the Austrian Academy of Sciences and the University of Vienna, as well as physicists at Harvey Mudd College and the University of California at San Diego.

A decision, made billions of years ago

In 2014, Kaiser and two members of the current team, Jason Gallicchio and Andrew Friedman,proposed an experimentto produce entangled photons on Earth -- a process that is fairly standard in studies of quantum mechanics. They planned to shoot each member of the entangled pair in opposite directions, toward light detectors that would also make a measurement of each photon using a polarizer. Researchers would measure the polarization, or orientation, of each incoming photon's electric field, by setting the polarizer at various angles and observing whether the photons passed through -- an outcome for each photon that researchers could compare to determine whether the particles showed the hallmark correlations predicted by quantum mechanics.

The team added a unique step to the proposed experiment, which was to use light from ancient, distant astronomical sources, such as stars and quasars, to determine the angle at which to set each respective polarizer. As each entangled photon was in flight, heading toward its detector at the speed of light, researchers would use a telescope located at each detector site to measure the wavelength of a quasar's incoming light. If that light was redder than some reference wavelength, the polarizer would tilt at a certain angle to make a specific measurement of the incoming entangled photon -- a measurement choice that was determined by the quasar. If the quasar's light was bluer than the reference wavelength, the polarizer would tilt at a different angle, performing a different measurement of the entangled photon.

In their previous experiment, the team used small backyard telescopes to measure the light from stars as close as 600 light years away. In their new study, the researchers used much larger, more powerful telescopes to catch the incoming light from even more ancient, distant astrophysical sources: quasars whose light has been traveling toward the Earth for at least 7.8 billion years -- objects that are incredibly far away and yet are so luminous that their light can be observed from Earth.

Tricky timing

On Jan. 11, 2018, "the clock had just ticked past midnight local time," as Kaiser recalls, when about a dozen members of the team gathered on a mountaintop in the Canary Islands and began collecting data from two large, 4-meter-wide telescopes: the William Herschel Telescope and the Telescopio Nazionale Galileo, both situated on the same mountain and separated by about a kilometer.

One telescope focused on a particular quasar, while the other telescope looked at another quasar in a different patch of the night sky. Meanwhile, researchers at a station located between the two telescopes created pairs of entangled photons and beamed particles from each pair in opposite directions toward each telescope.

In the fraction of a second before each entangled photon reached its detector, the instrumentation determined whether a single photon arriving from the quasar was more red or blue, a measurement that then automatically adjusted the angle of a polarizer that ultimately received and detected the incoming entangled photon.

"The timing is very tricky," Kaiser says. "Everything has to happen within very tight windows, updating every microsecond or so."

Demystifying a mirage

The researchers ran their experiment twice, each for around 15 minutes and with two different pairs of quasars. For each run, they measured 17,663 and 12,420 pairs of entangled photons, respectively. Within hours of closing the telescope domes and looking through preliminary data, the team could tell there were strong correlations among the photon pairs, beyond the limit that Bell calculated, indicating that the photons were correlated in a quantum-mechanical manner.

Guth led a more detailed analysis to calculate the chance, however slight, that a classical mechanism might have produced the correlations the team observed.

He calculated that, for the best of the two runs, the probability that a mechanism based on classical physics could have achieved the observed correlation was about 10 to the minus 20 -- that is, about one part in one hundred billion billion, "outrageously small," Guth says. For comparison, researchers have estimated the probability that the discovery of the Higgs boson was just a chance fluke to be about one in a billion.

"We certainly made it unbelievably implausible that a local realistic theory could be underlying the physics of the universe," Guth says.

And yet, there is still a small opening for the freedom-of-choice loophole. To limit it even further, the team is entertaining ideas of looking even further back in time, to use sources such as cosmic microwave background photons that were emitted as leftover radiation immediately following the Big Bang, though such experiments would present a host of new technical challenges.

"It is fun to think about new types of experiments we can design in the future, but for now, we are very pleased that we were able to address this particular loophole so dramatically. Our experiment with quasars puts extremely tight constraints on various alternatives to quantum mechanics. As strange as quantum mechanics may seem, it continues to match every experimental test we can devise," Kaiser says.

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Consuming milk at breakfast lowers blood glucose throughout the day

Milk at breakfast may help keep blood glucose lower throughout the day.

A change in breakfast routine may provide benefits for the management of type 2 diabetes, according to a new study published in the Journal of Dairy Science. H. Douglas Goff, PhD, and the team of scientists from the Human Nutraceutical Research Unit at the University of Guelph, in collaboration with the University of Toronto, examined the effects of consuming high-protein milk at breakfast on blood glucose levels and satiety after breakfast and after a second meal. Milk consumed with breakfast cereal reduced postprandial blood glucose concentration compared with water, and high dairy protein concentration reduced postprandial blood glucose concentration compared with normal dairy protein concentration. The high-protein treatment also reduced appetite after the second meal compared with the low-protein equivalent.

"Metabolic diseases are on the rise globally, with type 2 diabetes and obesity as leading concerns in human health," Dr. Goff and team said. "Thus, there is impetus to develop dietary strategies for the risk reduction and management of obesity and diabetes to empower consumers to improve their personal health."

In this randomized, controlled, double-blinded study, the team examined the effects of increasing protein concentration and increasing the proportion of whey protein in milk consumed with a high-carbohydrate breakfast cereal on blood glucose, feelings of satiety, and food consumption later in the day. Digestion of the whey and casein proteins naturally present in milk releases gastric hormones that slow digestion, increasing feelings of fullness. Digestion of whey proteins achieves this effect more quickly, whereas casein proteins provide a longer lasting effect.

Although the team only found a modest difference in food consumption at the lunch meal when increasing whey protein at breakfast, they did find that milk consumed with a high-carbohydrate breakfast reduced blood glucose even after lunch, and high-protein milk had a greater effect. Milk with an increased proportion of whey protein had a modest effect on pre-lunch blood glucose, achieving a greater decrease than that provided by regular milk.

According to Dr. Goff and colleagues, "This study confirms the importance of milk at breakfast time to aid in the slower digestion of carbohydrate and to help maintain lower blood sugar levels. Nutritionists have always stressed the importance of a healthy breakfast, and this study should encourage consumers to include milk."

From Science Daily

DNA analysis of 6,500-year-old human remains with blue eye mutation

Ossuaries from the Chalcolithic Period, excavated at Peqi'in Cave.

An international team of researchers from Tel Aviv University, the Israel Antiquities Authority and Harvard University has discovered that waves of migration from Anatolia and the Zagros mountains (today's Turkey and Iran) to the Levant helped develop the Chalcolithic culture that existed in Israel's Upper Galilee region some 6,500 years ago.

The study is one of the largest ancient DNA studies ever conducted in Israel and for the first time sheds light on the origins of the Chalcolithic culture in the Levant, approximately 6,000-7,000 years ago.

Research for the study was led by Dr. Hila May and Prof. Israel Hershkovitz of the Department of Anatomy and Anthropology, Dan David Center for Human Evolution and Biohistory Research, at TAU's Sackler Faculty of Medicine; Dr. Dina Shalem of the Institute for Galilean Archaeology at Kinneret College and the Israel Antiquities Authority; and Éadaoin Harney and Prof. David Reich of Harvard University. It was published today in Nature Communications.

In 1995, Zvi Gal, Dina Shalem and Howard Smithline of the Israel Antiquities Authority began excavating the Peqi'in Cave in northern Israel, which dates to the Chalcolithic Period in the Levant. The team unearthed dozens of burials in the natural stalactite cave that is 17 meters long and 5-8 meters wide.

The large number of unique ceramic ossuaries and the variety of burial offerings discovered in the cave suggest that it was once used as a mortuary center by the local Chalcolithic people.

"The uniqueness of the cave is evident in the number of people buried in it -- more than 600 -- and the variety of ossuaries and jars and the outstanding motifs on them, including geometric and anthropomorphic designs," Dr. Shalem says. "Some of the findings in the cave are typical to the region, but others suggest cultural exchange with remote regions.

"The study resolves a long debate about the origin of the unique culture of the Chalcolithic people. Did the cultural change in the region follow waves of migration, the infiltration of ideas due to trade relations and/or cultural exchange, or local invention? We now know that the answer is migration."

The researchers subjected 22 of the skeletons excavated at Peqi'in, dating to the Chalcolithic Period, to a whole genome analysis.

"This study of 22 individuals is one of the largest ancient DNA studies carried out from a single archaeological site, and by far the largest ever reported in the Near East," Dr. May says.

"The genetic analysis provided an answer to the central question we set out to address," says Prof. Reich. "It showed that the Peqi'in people had substantial ancestry from northerners -- similar to those living in Iran and Turkey -- that was not present in earlier Levantine farmers."

"Certain characteristics, such as genetic mutations contributing to blue eye color, were not seen in the DNA test results of earlier Levantine human remains," adds Dr. May. "The chances for the success of such a study seemed slim, since most of the ancient DNA studies carried out in Israel have failed due to difficult climatic conditions in the region that destroy DNA."

"Fortunately, however, human DNA was preserved in the bones of the buried people in Peqi'in cave, likely due to the cool conditions within the cave and the limestone crust that covered the bones and preserved the DNA," says Prof. Hershkovitz.

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New kind of aurora is not an aurora at all

The atmospheric phenomenon 'STEVE' which appears as a purple and green light ribbon in the sky.

Thin ribbons of purple and white light that sometimes appear in the night sky were dubbed a new type of aurora when brought to scientists' attention in 2016. But new research suggests these mysterious streams of light are not an aurora at all but an entirely new celestial phenomenon.

Amateur photographers had captured the new phenomenon, called STEVE, on film for decades. But the scientific community only got wind of STEVE in 2016. When scientists first looked at images of STEVE, they realized the lights were slightly different than light from typical auroras but were not sure what underlying mechanism was causing them.

In a new study, researchers analyzed a STEVE event in March 2008 to see whether it was produced in a similar manner as the aurora, which happens when showers of charged rain down into Earth's upper atmosphere. The study's results suggest STEVE is produced by a different atmospheric process than the aurora, making it an entirely new type of optical phenomenon.

"Our main conclusion is that STEVE is not an aurora," said Bea Gallardo-Lacourt, a space physicist at the University of Calgary in Canada and lead author of the new study in Geophysical Research Letters, a journal of the American Geophysical Union. "So right now, we know very little about it. And that's the cool thing, because this has been known by photographers for decades. But for the scientists, it's completely unknown."

The study authors have dubbed STEVE a kind of "skyglow," or glowing light in the night sky, that is distinct from the aurora.

Studying STEVE can help scientists better understand the upper atmosphere and the processes generating light in the sky, according to the authors.

"This is really interesting because we haven't figured it out and when you get a new problem, it's always exciting," said Joe Borovsky, a space physicist at the Space Science Institute in Los Alamos, New Mexico who was not connected to the new study. "It's like you think you know everything and it turns out you don't."

A different kind of light show

Auroras are produced when electrons and protons from Earth's magnetosphere, the region around Earth dominated by its magnetic field, rain down into the ionosphere, a region of charged particles in the upper atmosphere. When these electrons and protons become excited, they emit light of varying colors, most often green, red and blue.

A group of amateur auroral photographers brought STEVE to scientists' attention in 2016. A Facebook ground called the Alberta Aurora Chasers had occasionally noticed bright, thin streams of white and purple light running east to west in the Canadian night sky when they photographed the aurora.

Auroras are visible every night if viewing conditions are right, but the thin light ribbons of STEVE were only visible a few times per year. The light from STEVE was also showing up closer to the equator than the aurora, which can only be seen at high latitudes.

The photographers first thought the light ribbons were created by excited protons, but protons can only be photographed with special equipment. The light protons produce falls out of the range of wavelengths picked up by normal cameras.

The aurora chasers dubbed the light ribbon occurrences "Steve," a reference to the 2006 film Over the Hedge. When researchers presented data about the unusual lights at a 2016 scientific conference, a fellow space physicist proposed converting the name into the backronym STEVE, which stands for Strong Thermal Emission Velocity Enhancement, and the researchers adopted it.

Where does STEVE come from?

Scientists then started using data from satellites and images from ground-based observatories to try to understand what was causing the unusual light streaks. The first scientific study published on STEVE found a stream of fast-moving ions and super-hot electrons passing through the ionosphere right where STEVE was observed. The researchers suspected these particles were connected to STEVE somehow but were unsure whether they were responsible for producing it.

After that first study, of which Gallardo-Lacourt was a co-author, the researchers wanted to find out if STEVE's light is produced by particles raining down into the ionosphere, as typically happens with the aurora, or by some other process. In the new study, Gallardo-Lacourt and her colleagues analyzed a STEVE event that happened over eastern Canada on March 28, 2008, using images from ground-based cameras that record auroras over North America.

They coupled the images with data from NOAA's Polar Orbiting Environmental Satellite 17 (POES-17), which happened to pass directly over the ground-based cameras during the STEVE event. The satellite is equipped with an instrument that can measure charged particles precipitating into the ionosphere.

The study's results suggest STEVE is an entirely new phenomenon distinct from typical auroras. The POES-17 satellite detected no charged particles raining down to the ionosphere during the STEVE event, which means it is likely produced by an entirely different mechanism, according to the authors.

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Stone tools reveal modern human-like gripping capabilities 500,000 years ago

Comparison between a Handaxe and a Clovis Point

This research is the first to link a stone tool production technique known as 'platform preparation' to the biology of human hands. Demonstrating that without the ability to perform highly forceful precision grips, our ancestors would not have been able to produce advanced types of stone tool like spear points.

The technique involves preparing a striking area on a tool to remove specific stone flakes and shape the tool into a pre-conceived design.

Platform preparation is essential for making many different types of advanced prehistoric stone tool, with the earliest known occurrence observed at the 500,000-year-old site of Boxgrove in West Sussex (UK).

The study, led by Dr Alastair Key, of the University's School of Anthropology and Conservation, and funded by the British Academy, investigated how hands are used during the production of different types of early stone technology.

Using sensors attached to the hand of skilled flint knappers (stone tool producers), the researchers were able to identify that platform preparation behaviours required the hand to exert significantly more pressure through the fingers when compared to all other stone tool activities studied.

The research demonstrates that the Boxgrove hominins (early humans) would have needed significantly stronger grips compared to earlier populations who did not perform this behaviour. It further suggests that highly modified and shaped stone tools, such as the handaxes discovered at Boxgrove and stone spear points found in later prehistory, may not have been possible to produce until humans evolved the ability to perform particularly forceful grips.

This discovery is particularly important because human hand bones rarely survive in the fossil record.

Dr Key said: 'Hand bones from before 300,000 years ago are rare, particularly when compared to other human fossils such as teeth, so the fact we can study the manipulative capabilities of our early ancestors from the stone tools they produced is incredibly exciting'.

From Science Daily

Hubble paints picture of the evolving universe

Astronomers have just assembled one of the most comprehensive portraits yet of the universe's evolutionary history, based on a broad spectrum of observations by the Hubble Space Telescope and other space and ground-based telescopes. In particular, Hubble's ultraviolet vision opens a new window on the evolving universe, tracking the birth of stars over the last 11 billion years back to the cosmos' busiest star-forming period, about 3 billion years after the big bang. This photo encompasses a sea of approximately 15,000 galaxies -- 12,000 of which are star-forming -- widely distributed in time and space. This mosaic is 14 times the area of the Hubble Ultra Violet Ultra Deep Field released in 2014.

Astronomers using the ultraviolet vision of NASA's Hubble Space Telescope have captured one of the largest panoramic views of the fire and fury of star birth in the distant universe. The field features approximately 15,000 galaxies, about 12,000 of which are forming stars. Hubble's ultraviolet vision opens a new window on the evolving universe, tracking the birth of stars over the last 11 billion years back to the cosmos' busiest star-forming period, which happened about 3 billion years after the big bang.

Ultraviolet light has been the missing piece to the cosmic puzzle. Now, combined with infrared and visible-light data from Hubble and other space and ground-based telescopes, astronomers have assembled one of the most comprehensive portraits yet of the universe's evolutionary history.

The image straddles the gap between the very distant galaxies, which can only be viewed in infrared light, and closer galaxies, which can be seen across a broad spectrum. The light from distant star-forming regions in remote galaxies started out as ultraviolet. However, the expansion of the universe has shifted the light into infrared wavelengths. By comparing images of star formation in the distant and nearby universe, astronomers glean a better understanding of how nearby galaxies grew from small clumps of hot, young stars long ago.

Because Earth's atmosphere filters most ultraviolet light, Hubble can provide some of the most sensitive space-based ultraviolet observations possible.

The program, called the Hubble Deep UV (HDUV) Legacy Survey, extends and builds on the previous Hubble multi-wavelength data in the CANDELS-Deep (Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey) fields within the central part of the GOODS (The Great Observatories Origins Deep Survey) fields. This mosaic is 14 times the area of the Hubble Ultra Violet Ultra Deep Field released in 2014.

This image is a portion of the GOODS-North field, which is located in the northern constellation Ursa Major.

The Hubble Space Telescope is a project of international cooperation between NASA and ESA (European Space Agency). NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope.

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99-million-year-old beetle trapped in amber served as pollinator to evergreen cycads

This image shows a dorsal view of the mid-Cretaceous beetle Cretoparacucujus cycadophilus, including the mandibular cavities it likely used for pollination.

Flowering plants are well known for their special relationship to the insects and other animals that serve as their pollinators. But, before the rise of angiosperms, another group of unusual evergreen gymnosperms, known as cycads, may have been the first insect-pollinated plants. Now, researchers reporting in the journal Current Biology on August 16 have uncovered the earliest definitive fossil evidence of that intimate relationship between cycads and insects.

The discovery came in the form of an ancient boganiid beetle preserved in Burmese amber for an estimated 99 million years along with grains of cycad pollen. The beetle also shows special adaptations, including mandibular patches, for the transport of cycad pollen.

"Boganiid beetles have been ancient pollinators for cycads since the Age of Cycads and Dinosaurs," says Chenyang Cai, now a research fellow at the University of Bristol. "Our find indicates a probable ancient origin of beetle pollination of cycads at least in the Early Jurassic, long before angiosperm dominance and the radiation of flowering-plant pollinators, such as bees, later in the Cretaceous."

When Cai's supervisor Diying Huang at the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, first showed him the beetle trapped in amber, he was immediately intrigued. He recognized that its large mandibles with bristly cavities might suggest the beetle was a pollinator of cycads.

After cutting, trimming, and polishing the specimen to get a better look under a microscope, Cai's excitement only grew. The beetle carried several clumps of tiny pollen grains. Cai consulted Liqin Li, an expert in ancient pollen at the Chinese Academy of Sciences, who confirmed that the pollen grains belonged to a cycad.

The researchers also conducted an extensive phylogenetic analysis to explore the beetle's family tree. Their analysis indicates the fossilized beetle belonged to a sister group to the extant Australian Paracucujus, which pollinate the relic cycad Macrozamia riedlei. The finding, along with the current disjunct distribution of related beetle-herbivore and cycad-host pairs in South Africa and Australia, support an ancient origin of beetle pollination of cycads, the researchers say.

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