Liquid water is more than just H2O molecules 

SOMEBODY IS PLAYING WITH NUCLEAR PHYSICS 


SKOLKOVO INSTITUTE OF SCIENCE AND TECHNOLOGY (SKOLTECH)


IMAGE: INFRARED SPECTRA OF LIGHT (RED), HEAVY (BLUE), SEMIHEAVY (GRAY) WATER, AND IONIC SPECIES THAT HAVE BEEN IDENTIFIED IN THE CURRENT STUDY. RED, WHITE AND BLACK CIRCLES DEPICT OXYGEN, HYDROGEN AND... view more

CREDIT: SKOLTECH

Skoltech scientists in collaboration with researchers from the University of Stuttgart showed that the concentration of short-lived ions (H3O+ and OH-) in pure liquid water is much higher than that assumed to evaluate the pH, hence significantly changing our understanding of the dynamical structure of water.

Figure: infrared spectra of light (red), heavy (blue), semiheavy (gray) water, and ionic species that have been identified in the current study. Red, white and black circles depict oxygen, hydrogen and deuterium atoms, respectively. Arrows show the directions of species vibrational deformation.

Intrinsic ionic species of liquid water play an important role in the redox processes, catalytic reactions and electrochemical systems. A low-barrier tunneling of hydrogen atom between the H2O molecules, caused by nuclear quantum effects, is expected to generate short-lived excess proton states. However, to date, there has been no information on the concentration of such excess protons states in pure water.

Skoltech scientists in collaboration with German researchers measured the ion-molecular composition of liquid water on the sub-picosecond time scale. The result surprised scientists as they observed that up to several percent of H2O molecules were temporarily ionized.

"We used water isotopologues: ordinary (H2O), heavy (D2O), and semi-heavy (HDO) water, to identify excess-proton states. By gradually substituting the hydrogen atoms (H) with deuterium (D), we changed the relative concentration of excess-proton-related species, such as HD2O+, DH2O+, H3O+ and D3O+, and identified their contributions to the cumulative infrared absorption. 

We found concentration-dependent spectral features near molecular bending modes of semi-heavy water spectra that no known model was able to explain. 

We associated these features with excess protons that may be expected to exist on the picosecond time scale," said one of the co-authors, Prof. Henni Ouerdane from the Skoltech Center for Energy Science and Technology (CEST).

"While previous studies of water structure were based on crystallographic experiments, and did not reflect the dynamics of water, our research brings new insights into the intricate water structure at ultra-short time scale. The finding anticipates new effects of electric field interaction with water, as well as other anomalous properties of water," concluded the lead author, Dr. Vasily Artemov, Senior Research Scientist at CEST.

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LIKE 9/11 FIRST RESPONDERS WERE POISONED 

fallout from Notre Dame fire was likely overlooked

A ton of lead dust may have been deposited near the cathedral

EARTH INSTITUTE AT COLUMBIA UNIVERSITY

IMAGE: SOIL SAMPLES TAKEN IN THE VICINITY OF NOTRE DAME CATHEDRAL SHOW HIGH LEVELS OF LEAD FROM THE 2019 FIRE. AN INTERACTIVE VERSION OF THIS MAP, SHOWING IMAGES OF INDIVIDUAL SAMPLE... view more 

CREDIT: INTERACTIVE MAP BY JEREMY HINSDALE/EARTH INSTITUTE. PHOTOS BY ALEXANDER VAN GEEN.

On April 15, 2019, the world watched helplessly as black and yellow smoke billowed from the Notre Dame cathedral in Paris. The fire started just below the cathedral's roof and spire, which were covered in 460 tons of lead -- a neurotoxic metal, dangerous especially to children, and the source of the yellow smoke that rose from the fire for hours. The cathedral is being restored, but questions have remained about how much lead the fire emitted into the surrounding neighborhoods, and how much of a threat it posed to the health of people living nearby.

A new study, published today in GeoHealth, used soil samples collected from neighborhoods around the cathedral to estimate local amounts of lead fallout from the fire. Lead levels in the soil samples indicated that nearly a ton of lead dust dropped down within one kilometer (0.6 miles) of the site, and areas downwind of the fire had double the lead levels than sites that were outside the path of the smoke plume. The study concludes that, for a brief time, people residing within a kilometer and downwind of the fire were probably more exposed to lead fallout than measurements by French authorities indicated.

Early evidence suggested that the fire increased lead exposure in Paris. Air quality measurements taken 50 kilometers away from the cathedral found that lead particulates in the air were 20 times higher than usual in the week after the fire. However, a small set of measurements by France's Regional Health Agency, posted weeks after the fire, found that all the samples collected outside of the out-of-bounds area around the cathedral had lead levels below France's limit of 300 milligrams per kilogram of soil. At the time, there were fears that the health agency was underplaying the potential health impacts and not being transparent enough.

"There was a controversy -- were children being exposed or not from this fallout?" said Lex van Geen, a geochemist at Columbia University's Lamont-Doherty Earth Observatory and lead author on the new study. "So I thought, whether I get a 'yes' or a 'no,' it's worth documenting."

In December 2019 and February 2020, van Geen collected 100 soil samples from tree pits, parks and other locations around the cathedral, and in particular to the northwest, where most of the smoke traveled on the day of the fire. When lead enters soil, it tends to stay put, so it can preserve the signal of the fallout for much longer than hard surfaces such as roads and sidewalks, which get swept and flushed by rain.

"It wasn't a particularly glamorous expedition," said van Geen. "I got plenty of strange looks from people wondering why this old guy was scooping up soil, trying to avoid the dog poop, and putting some of the soil in paper bags. But it got done."

Non-contaminated soil would be expected to contain less than less than 100 milligrams of lead per kilogram of soil. However, in samples collected within a kilometer the cathedral's remains, the levels averaged 200 mg/kg. And in the northwest direction downwind of the fire, the lead was significantly higher, averaging nearly 430 mg/kg -- double that of the surrounding area, and surpassing France's 300 mg/kg limit.

A soil-sample site near the cathedral. Paper bag contains the sample

Because the sample sites weren't uniformly distributed, co-authors Yuling Yao and Andrew Gelman from Columbia University's Statistics Department used statistical methods to predict the overall distribution of lead, calculate the averages inside and outside of the plume, and estimate the total amount of lead that fell near the fire. By their calculations, 1,000 kilograms (2,200 pounds) of lead settled within a kilometer of the cathedral. That's six times higher than the current estimate for the amount of lead fallout between 1 and 20 kilometers of the site.

"Our final estimation of the total amount of excess lead is much larger compared with what has been reported earlier by other teams," said Yao. "Of course, we are measuring slightly different things, but ultimately all disagreement in scientific findings shall be validated by more data, especially when they have profound policy and public health consequences. I hope our work sheds some light in that direction."

It is difficult to ascertain how this lead may have affected human health, because too few soil, dust, and blood samples were collected immediately after the fire, said van Geen. The impacts are likely much lower than those of leaded gasoline, which was entirely phased out by the year 2000. Nevertheless, lead could have posed a brief but significant health hazard to children living downwind of the fire.

On June 4, seven weeks after the fire, the French government made blood tests available at a local hospital on an on-demand basis. This only occurred after a child in a nearby apartment was found to have a concerning level of lead in their blood. (Subsequent investigation identified a different source of lead as the more likely culprit in this case.) Soil and dust tests were similarly delayed and limited in scope.

To van Geen, the government showed it had the means to respond but it didn't do so quickly enough. He says that the urgency of the situation should have been more clearly conveyed with pro-active collection and posting of environmental and blood-lead data. This would have induced more parents downwind of the fire to remove indoor dust with wet wipes at home and prevent kids from playing in soil, thereby reducing their chances of exposure.

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The paper, 'Fallout of Lead over Paris from the 2019 Notre-Dame Cathedral Fire,' can be obtained from the authors or news@agu.org

Scientist contact: Alexander van Geen: avangeen@ldeo.columbia.edu

More information: Kevin Krajick, Senior editor, science news, The Earth Institute kkrajick@ei.columbia.edu 212-854-9729

Lamont-Doherty Earth Observatory is Columbia University's home for Earth science research. Its scientists develop fundamental knowledge about the origin, evolution and future of the natural world, from the planet's deepest interior to the outer reaches of its atmosphere, on every continent and in every ocean, providing a rational basis for the difficult choices facing humanity. http://www.ldeo.columbia.edu | @LamontEarth

The Earth Institute, Columbia University mobilizes the sciences, education and public policy to achieve a sustainable earth. http://www.earth.columbia.edu.

Sensation seekers, risk-takers who experience more bitterness apt to drink IPAs

PENN STATE

 

IMAGE: A LAGER BEER AND TWO PALE-ALE-STYLE BEERS WERE CHOSEN AS THE TEST STIMULI. THE SPECIFIC BEER SAMPLES WERE SELECTED BY RESEARCH STAFF FOLLOWING BENCHTOP TASTING OF VARIOUS COMMERCIAL PALE-ALE-STYLE BEERS... view more 

CREDIT: MOLLY HIGGINS, PENN STATE

People who seek novel and powerful sensations and are more prone to taking risks -- and who perceive bitter tastes more intensely -- are more likely to prefer bitter, pale-ale-style beers and drink them more often, according to Penn State sensory researchers, who conducted a study that involved blind taste tests and personality assessments.

The results of the study, which involved more than 100 beer consumers, were unexpected, explained researcher John Hayes, associate professor of food science, because previous research typically indicates that greater perceived bitterness leads to decreased intake of bitter foods and drinks.

"Traditionally, most researchers find that people who experience bitterness more intensely avoid bitter food or drink -- so with heightened bitterness, they like it less, and therefore consume it less," he said. "But here, we find that people who seek higher sensations and are more risk-taking, they like bitter beer such as India pale ales, if they also have greater bitter taste perception."

The connection between food liking and personality has been seen before, noted Hayes, director of Penn State's Sensory Evaluation Center. In a study spearheaded by one of his former doctoral students, his research group in the College of Agricultural Sciences found robust links between the liking of spicy foods and the high-sensation-seeking, risk-taking personality traits. Studies done in Mexico and Italy also have revealed similar findings.

These results highlight the importance of considering personality traits such as sensation seeking when considering the relationship between bitterness perception and the liking and intake of bitter food and beverage products, said lead researcher Molly Higgins, who will receive her doctoral degree in food science this August.

"Our data contradict the classic view that bitterness is merely an aversive sensation that limits intake. We found that increased bitterness perception does not always lead to decreased liking and intake -- rather, it's a positive attribute in some products for some consumers."

In Higgins' study, 109 beer consumers rated liking and intensity of two pale ales and a lager, and the intensity of two bitter solutions -- quinine, the compound that makes tonic water bitter, and hops extract Tetralone -- under blind laboratory conditions. Participants also completed intake and personality questionnaires. A liking ratio for each beer was calculated from each participant's liking for that specific beer and their total liking for all beers.

Participants, about half men and half women, most in their 30s, were classified as weekly, monthly or yearly pale-ale consumers using intake data. Using intensity ratings, personality measures and other parameters, the researchers developed models to predict liking ratios and beer-intake frequency.

A lager beer and two pale-ale-style beers were chosen as the test stimuli. The specific beer samples were selected by research staff following benchtop tasting of various commercial pale-ale-style beers sold in Pennsylvania. To represent the range of bitterness in commercial pale ales, researchers selected one pale ale that was strongly bitter and one that was moderately bitter.

To represent a lager-style beer with low bitterness, research staff selected Budweiser. The pale-ale-style beers used in the study were Founder's All-Day IPA Session Ale as the moderately bitter ale, and Troeg's Perpetual IPA Imperial Pale Ale, as the strongly bitter ale.

A significant interaction between sensation seeking and quinine bitterness was found for the liking ratio of the imperial pale ale, Higgins pointed out. But the relationship was not straightforward.

"The interaction revealed liking of the pale ale increased with sensation seeking but only if quinine bitterness was also high," she said. "Intake models showed increased odds of frequent pale-ale intake with greater quinine bitterness and lower liking for lager beer. These data suggest liking and intake of pale ales is positively related to sensation seeking and bitter taste perception."

The findings, recently published in Food Quality and Preference, suggest that further research on the relationship between personality traits and the liking and intake of bitter foods and beverages may lead to new strategies to promote consumption of healthy bitter foods, Higgins contended.

"Avoidance of bitter foods can impact health negatively, because bitter foods such as cruciferous vegetables, green tea and grapefruit contain healthy compounds like flavonols, which are reported to have antioxidant and anticarcinogenic properties," she said.

Alyssa Bakke, staff sensory scientist in food science, also was involved in the research.

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The U.S. Department of Agriculture's Agriculture and Food Research Initiative supporte

Pasteurizing breast milk inactivates SARS-CoV-2 

CANADIAN MEDICAL ASSOCIATION JOURNAL

Pasteurizing breast milk using a common technique inactivates severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) making it safe for use, according to new research in CMAJ (Canadian Medical Association Journal)

Current advice is for women with coronavirus disease 2019 (COVID-19) to continue to breastfeed their own infants. In Canada, it is standard care to provide pasteurized breast milk to very-low-birth-weight babies in hospital until their own mother's milk supply is adequate.

"In the event that a woman who is COVID-19-positive donates human milk that contains SARS-CoV-2, whether by transmission through the mammary gland or by contamination through respiratory droplets, skin, breast pumps and milk containers, this method of pasteurization renders milk safe for consumption," writes Dr. Sharon Unger, a neonatologist at Sinai Health and professor at the University of Toronto, who is medical director of the Rogers Hixon Ontario Human Milk Bank, with coauthors.

The Holder method, a technique used to pasteurize milk in all Canadian milk banks (62.5°C for 30 minutes), is effective at neutralizing viruses such as HIV, hepatitis and others that are known to be transmitted through human milk. In this study, researchers spiked human breast milk with a viral load of SARS-CoV-2 and tested samples that either sat at room temperature for 30 minutes or were warmed to 62.5°C for 30 minutes, and then measured for active virus. The virus in the pasteurized milk was inactivated after heating.

More than 650 human breast milk banks around the world use the Holder method to ensure a safe supply of milk for vulnerable infants.

The authors report that the impact of pasteurization on coronaviruses in human milk has not been previously reported in the scientific literature.

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Challenges in evaluating SARS-CoV-2 vaccines

 CANADIAN MEDICAL ASSOCIATION JOURNAL

With more than 140 SARS-CoV-2 vaccines in development, the race is on for a successful candidate to help prevent COVID-19. An effective and safe vaccine would be a major advance in the fight against COVID-19. However, there are challenges in evaluating the efficacy of these vaccines during the pandemic, as an analysis article outlines in CMAJ (Canadian Medical Association Journal).

Those evaluating vaccine efficacy must take into account the risk of infection in the population being studied, use of social distancing practices, rates of pre-existing immunity from earlier COVID-19 and factors that influence the likelihood of severe COVID-19.

"The dynamic and rapidly changing pattern of virus exposure and level of population immunity during the evolving pandemic are potentially important confounders in the assessment of the efficacy of SARS-CoV-2 vaccines," writes Dr. Bahaa Abu-Raya, BC Children's Hospital, Vancouver, British Columbia, with coauthors. "This should be considered in sample size calculations for efficacy trials."

Some considerations:

• Adequate sample sizes are needed to demonstrate effect of a vaccine in reducing disease and may need to be revised based on rates of SAR-CoV-2 transmission in study populations.
• Public health interventions such as social distancing may reduce transmission and affect ongoing assessment of SARS-CoV-2 vaccines.
• The baseline level of immunity could influence a trial outcome. For example, the benefit of a highly efficacious vaccine may not be evident in a population with high levels of previous exposure later in the pandemic.
• There is a possibility that COVID-19 might be more severe in some people who have been vaccinated (called antibody-dependent enhancement [ADE]). This should be monitored as vaccine-related ADE may be evident only after large numbers of vaccinated people have been exposed to the virus and followed for some time.

The authors emphasize the need to test vaccines in vulnerable populations such as seniors, health care workers, Black people and those with risk factors for severe disease and who may have a different response than younger, healthier trial participants.

"The changing dynamics of the COVID-19 pandemic present a unique challenge for evaluating vaccines for SARS-CoV-2," says author Dr. Manish Sadarangani, Director of the Vaccine Evaluation Center at BC Children's Hospital and Sauder Family Chair in Pediatric Infectious Diseases at the University of British Columbia. "Researchers need to understand the immune responses generated after infection with this virus and whether they are protective, as this will help to inform the development and evaluation of these vaccines."

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Earth's magnetic field can change 10 times faster than previously thought

A new study reveals that changes in the direction of the Earth's magnetic field may take place 10 times faster than previously thought.

Date:July 6, 2020

Source:University of Leeds

A new study by the University of Leeds and University of California at San Diego reveals that changes in the direction of the Earth's magnetic field may take place 10 times faster than previously thought.

Their study gives new insight into the swirling flow of iron 2800 kilometres below the planet's surface and how it has influenced the movement of the magnetic field during the past hundred thousand years.

Our magnetic field is generated and maintained by a convective flow of molten metal that forms the Earth's outer core. Motion of the liquid iron creates the electric currents that power the field, which not only helps guide navigational systems but also helps shield us from harmful extra terrestrial radiation and hold our atmosphere in place.

The magnetic field is constantly changing. Satellites now provide new means to measure and track its current shifts but the field existed long before the invention of human-made recording devices. To capture the evolution of the field back through geological time scientists analyse the magnetic fields recorded by sediments, lava flows and human-made artefacts. Accurately tracking the signal from Earth's core field is extremely challenging and so the rates of field change estimated by these types of analysis are still debated.

Now, Dr Chris Davies, associate professor at Leeds and Professor Catherine Constable from the Scripps Institution of Oceanography, UC San Diego, in California have taken a different approach. They combined computer simulations of the field generation process with a recently published reconstruction of time variations in Earth's magnetic field spanning the last 100,000 years

Their study, published in Nature Communications, shows that changes in the direction of Earth's magnetic field reached rates that are up to 10 times larger than the fastest currently reported variations of up to one degree per year.

They demonstrate that these rapid changes are associated with local weakening of the magnetic field. This means these changes have generally occurred around times when the field has reversed polarity or during geomagnetic excursions when the dipole axis -- corresponding to field lines that emerge from one magnetic pole and converge at the other -- moves far from the locations of the North and South geographic poles.

The clearest example of this in their study is a sharp change in the geomagnetic field direction of roughly 2.5 degrees per year 39,000 years ago. This shift was associated with a locally weak field strength, in a confined spatial region just off the west coast of Central America, and followed the global Laschamp excursion -- a short reversal of the Earth's magnetic field roughly 41,000 years ago.

Similar events are identified in computer simulations of the field which can reveal many more details of their physical origin than the limited paleomagnetic reconstruction.

Their detailed analysis indicates that the fastest directional changes are associated with movement of reversed flux patches across the surface of the liquid core. These patches are more prevalent at lower latitudes, suggesting that future searches for rapid changes in direction should focus on these areas.

Dr Davies, from the School of Earth and Environment, said: "We have very incomplete knowledge of our magnetic field prior to 400 years ago. Since these rapid changes represent some of the more extreme behaviour of the liquid core they could give important information about the behaviour of Earth's deep interior."

Professor Constable said: "Understanding whether computer simulations of the magnetic field accurately reflect the physical behaviour of the geomagnetic field as inferred from geological records can be very challenging.

"But in this case we have been able to show excellent agreement in both the rates of change and general location of the most extreme events across a range of computer simulations. Further study of the evolving dynamics in these simulations offers a useful strategy for documenting how such rapid changes occur and whether they are also found during times of stable magnetic polarity like what we are experiencing today."


Journal Reference:
Christopher J. Davies, Catherine G. Constable. Rapid geomagnetic changes inferred from Earth observations and numerical simulations. Nature Communications, 2020; 11 (1) DOI: 10.1038/s41467-020-16888-0

Cite This Page:

University of Leeds. "Earth's magnetic field can change 10 times faster than previously thought." ScienceDaily. ScienceDaily, 6 July 2020. .

Trump’s Floor Collapsed When COVID-19 Hit His Base

Conservatives often don’t care about America’s problems—until they are affected by them personally.

by Martin Longman July 6, 2020 POLITICAL ANIMAL

 I have long argued that conservatives’ innate empathy deficit requires them to suffer directly from societal problems and controversies before they will support basic concepts, like the value of the social safety net or the importance of medical research or the morality of same-sex marriage. We’ve seen this play out with the COVID-19 crisis, as the virus first hit urban centers and coastal regions rather than Republican strongholds

Republican governors, with only a few exceptions, did not take the pandemic seriously enough and put too much emphasis on reopening their economies. They are now suffering the consequences, and their constituents are turning on them, and on the president. Gallup shows Trump’s approval rating sinking to 38 percent, and the explanation is based almost entirely on new people being impacted by COVID-19.


Pew Research Center polls show Trump’s approval is slipping fastest in the 500 counties where the number of cases have been more than 28 coronavirus deaths per 100,000 people.

Pew surveyed voters in late March and the same people again in late June, and found 17% of those who approved of the president in March now disapprove.

The shift came almost equally among Democrats and Republicans, men and women, and college graduates and non-graduates. But those who live in counties with a high number of virus cases were 50% more likely to say they no longer approve of Trump.

It was easy for conservative-minded people, regardless of formal party affiliation, to maintain their support for Trump so long as the pandemic seemed far away and someone else’s fault. These are the folks who stubbornly stuck with the president through everything over the last three and a half years. They created the floor in Trump’s approval ratings.

But they are beginning to abandon him now that it’s their hospitals that are filled with coronavirus patients. They can see that things have not turned out the way that Trump or their Republican governors said they would. That’s why Trump’s approval numbers have dropped, and it’s also why Republican internal polling points to a coming rout at the hands of the Democrats.

Amazingly, as Yasmeen Abutaleb and Josh Dawsey report in the Washington Post, the administration seems to believe that their base of supporters will simply “get over it” and “move on” as they become inured to a steady and massive infection rate.

White House officials also hope Americans will grow numb to the escalating death toll and learn to accept tens of thousands of new cases a day, according to three people familiar with the White House’s thinking, who requested anonymity to reveal internal deliberations. Americans will “live with the virus being a threat,” in the words of one of those people, a senior administration official.

“They’re of the belief that people will get over it or if we stop highlighting it, the base will move on and the public will learn to accept 50,000 to 100,000 new cases a day,” said a former administration official in touch with the campaign.

I’m sure that many conservatives can be convinced to wander back to Trump if they feel less threatened by the virus in the fall. But he’s already done tremendous damage to himself. Conservatives voted for Trump in the hope that he’d ruin other people’s lives, not their own.



Martin Longman is the web editor for the Washington Monthly. See all his writing at ProgressPond.com

A tiny ancient relative of dinosaurs and pterosaurs discovered

New study suggests a miniaturized origin for some of the largest animals ever to live on Earth

ANOTHER AMAZING FIND IN THE MUSEUM STORAGE ROOM 

Date:July 6, 2020

Source:American Museum of Natural History

Dinosaurs and flying pterosaurs may be known for their remarkable size, but a newly described species from Madagascar that lived around 237 million years ago suggests that they originated from extremely small ancestors. The fossil reptile, named Kongonaphon kely, or "tiny bug slayer," would have stood just 10 centimeters (or about 4 inches) tall. The description and analysis of this fossil and its relatives, published today in the journal Proceedings of the National Academy of Sciences, may help explain the origins of flight in pterosaurs, the presence of "fuzz" on the skin of both pterosaurs and dinosaurs, and other questions about these charismatic animals.


"There's a general perception of dinosaurs as being giants," said Christian Kammerer, a research curator in paleontology at the North Carolina Museum of Natural Sciences and a former Gerstner Scholar at the American Museum of Natural History. "But this new animal is very close to the divergence of dinosaurs and pterosaurs, and it's shockingly small."

Dinosaurs and pterosaurs both belong to the group Ornithodira. Their origins, however, are poorly known, as few specimens from near the root of this lineage have been found. The fossils of Kongonaphon were discovered in 1998 in Madagascar by a team of researchers led by American Museum of Natural History Frick Curator of Fossil Mammals John Flynn (who worked at The Field Museum at the time) in close collaboration with scientists and students at the University of Antananarivo, and project co-leader Andre Wyss, chair and professor of the University of California-Santa Barbara's Department of Earth Science and an American Museum of Natural History research associate.

"This fossil site in southwestern Madagascar from a poorly known time interval globally has produced some amazing fossils, and this tiny specimen was jumbled in among the hundreds we've collected from the site over the years," Flynn said. "It took some time before we could focus on these bones, but once we did, it was clear we had something unique and worth a closer look. This is a great case for why field discoveries -- combined with modern technology to analyze the fossils recovered -- is still so important."

"Discovery of this tiny relative of dinosaurs and pterosaurs emphasizes the importance of Madagascar's fossil record for improving knowledge of vertebrate history during times that are poorly known in other places," said project co-leader Lovasoa Ranivoharimanana, professor and director of the vertebrate paleontology laboratory at the University of Antananarivo in Madagascar. "Over two decades, our collaborative Madagascar-U.S. teams have trained many Malagasy students in paleontological sciences, and discoveries like this helps people in Madagascar and around the world better appreciate the exceptional record of ancient life preserved in the rocks of our country."

Kongonaphon isn't the first small animal known near the root of the ornithodiran family tree, but previously, such specimens were considered "isolated exceptions to the rule," Kammerer noted. In general, the scientific thought was that body size remained similar among the first archosaurs -- the larger reptile group that includes birds, crocodilians, non-avian dinosaurs, and pterosaurs -- and the earliest ornithodirans, before increasing to gigantic proportions in the dinosaur lineage.

"Recent discoveries like Kongonaphon have given us a much better understanding of the early evolution of ornithodirans. Analyzing changes in body size throughout archosaur evolution, we found compelling evidence that it decreased sharply early in the history of the dinosaur-pterosaur lineage," Kammerer said.

This "miniaturization" event indicates that the dinosaur and pterosaur lineages originated from extremely small ancestors yielding important implications for their paleobiology. For instance, wear on the teeth of Kongonaphon suggests it ate insects. A shift to insectivory, which is associated with small body size, may have helped early ornithodirans survive by occupying a niche different from their mostly meat-eating contemporaneous relatives.

The work also suggests that fuzzy skin coverings ranging from simple filaments to feathers, known on both the dinosaur and pterosaur sides of the ornithodiran tree, may have originated for thermoregulation in this small-bodied common ancestor. That's because heat retention in small bodies is difficult, and the mid-late Triassic was a time of climatic extremes, inferred to have sharp shifts in temperature between hot days and cold nights.

Sterling Nesbitt, an assistant professor at Virginia Tech and a Museum research associate and expert in ornithodiran anatomy, phylogeny, and histological age analyses, is also an author on this study.

This study was supported, in part, by the National Geographic Society, a Gerstner Scholars Fellowship from the Gerstner Family Foundation and the Richard Gilder Graduate School, the Division of Paleontology at the American Museum of Natural History, and a Meeker Family Fellowship from the Field Museum, with additional support from the Ministry of Energy and Mines of Madagascar, the World Wide Fund for Nature (Madagascar), University of Antananarivo, and MICET/ICTE (Madagascar).

Related Multimedia:
Life restoration of Kongonaphon kely

Journal Reference:
Christian F. Kammerer, Sterling J. Nesbitt, John J. Flynn, Lovasoa Ranivoharimanana, André R. Wyss. A tiny ornithodiran archosaur from the Triassic of Madagascar and the role of miniaturization in dinosaur and pterosaur ancestry. Proceedings of the National Academy of Sciences, 2020; 201916631 DOI: 10.1073/pnas.1916631117


Cite This Page:
American Museum of Natural History. "A tiny ancient relative of dinosaurs and pterosaurs discovered: New study suggests a miniaturized origin for some of the largest animals ever to live on Earth." ScienceDaily. ScienceDaily, 6 July 2020. .

Fossil jawbone from Alaska is a rare case of a juvenile Arctic dromaeosaurid dinosaur

This fossil is a clue to the history of how dinosaurs dispersed between continents, showing some dinosaurs likely nested in the far north

Date:July 8, 2020 Source:PLOS

Summary:A small piece of fossil jawbone from Alaska represents a rare example of juvenile dromaeosaurid dinosaur remains from the Arctic, according to a new study.Share:

A small piece of fossil jawbone from Alaska represents a rare example of juvenile dromaeosaurid dinosaur remains from the Arctic, according to a study published July 8, 2020 in the open-access journal PLOS ONE by Alfio Alessandro Chiarenza of the Imperial College London, UK, and co-authors Anthony R. Fiorillo, Ronald S. Tykoski, Paul J. McCarthy, Peter P. Flaig, and Dori L. Contreras.

Dromaeosaurids are a group of predatory dinosaurs closely related to birds, whose members include well-known species such as Deinonychus and Velociraptor. These dinosaurs lived all over the world, but their bones are often small and delicate and rarely preserve well in the fossil record, complicating efforts to understand the paths they took as they dispersed between continents.

The Prince Creek Formation of northern Alaska preserves the largest collection of polar dinosaur fossils in the world, dating to about 70 million years ago, but the only dromaeosaurid remains found so far have been isolated teeth. The jaw fossil described in this study is a mere 14mm long and preserves only the tip of the lower jaw, but it is the first known non-dental dromaeosaurid fossil from the Arctic. Statistical analysis indicates this bone belongs to a close relative of the North American Saurornitholestes.

North American dromaeosaurids are thought to trace their origins to Asia, and Alaska would have been a key region for the dispersal of their ancestors. This new fossil is a tantalizing clue toward understanding what kinds of dromaeosaurs inhabited this crucial region. Furthermore, the early developmental stage of the bone suggests this individual was still young and was likely born nearby; in contrast to previous suggestions that this part of Alaska was exclusively a migratory pathway for many dinosaurs, this is strong evidence that some dinosaurs were nesting here. The authors suggest that future findings may allow a more complete understanding of these mysterious Arctic dromaeosaurids.

Chiarenza summarizes: "There are places where dinosaur fossils are so common that a scrap of bone, in most cases, cannot really add anything scientifically informative anymore: this is not the case with this Alaskan specimen. Even with such an incomplete jaw fragment, our team was not only able to work out the evolutionary relationships of this dinosaur, but also to picture something more on the biology of these animals, ultimately gaining more information on this Ancient Arctic ecosystem." Fiorillo adds: "Years ago when dinosaurs were first found in the far north, the idea challenged what we think we know about dinosaurs. For some time afterwards, there was a great debate as to whether or not those Arctic dinosaurs migrated or lived in the north year round. All of those arguments were somewhat speculative in nature. This study of a predatory dinosaur jaw from a baby provides the first physical proof that at least some dinosaurs not only lived in the far north, but they thrived there. One might even say, our study shows that the ancient north was a great place to raise a family and now we have to figure out why."

Journal Reference:
Alfio Alessandro Chiarenza, Anthony R. Fiorillo, Ronald S. Tykoski, Paul J. McCarthy, Peter P. Flaig, Dori L. Contreras. The first juvenile dromaeosaurid (Dinosauria: Theropoda) from Arctic Alaska. PLOS ONE, 2020; 15 (7): e0235078 DOI: 10.1371/journal.pone.0235078

PLOS. "Fossil jawbone from Alaska is a rare case of a juvenile Arctic dromaeosaurid dinosaur: This fossil is a clue to the history of how dinosaurs dispersed between continents, showing some dinosaurs likely nested in the far north." ScienceDaily. ScienceDaily, 8 July 2020. .

Stress testing 'coral in a box'

Summary:Coral death is impacting oceans worldwide as a consequence of climate change. The concern is that corals cannot keep pace with the rate of ocean warming. In particular, because a temperature increase of only one degree Celsius can make the difference between healthy and dying coral reefs. Some corals, however, are more resistant to increasing temperatures. In order to effectively protect coral reef habitats, it is important to identify which corals and reef sites are more resistant and thus have a greater chance of survival.

Date:July 8, 2020

Source:University of Konstanz

Coral death is impacting oceans worldwide as a consequence of climate change. The concern is that corals cannot keep pace with the rate of ocean warming. In particular, because a temperature increase of only one degree Celsius can make the difference between healthy and dying coral reefs. Some corals, however, are more resistant to increasing temperatures. In order to effectively protect coral reef habitats, it is important to identify which corals and reef sites are more resistant and thus have a greater chance of survival.

For this purpose, the research team led by Konstanz biologist Professor Christian Voolstra developed a rapid stress test to assess coral thermotolerance. The "Coral Bleaching Automated Stress System" (CBASS) makes it possible to assess coral thermotolerance on site and within a single day -- much faster than current experimental procedures that typically take several weeks to months in a laboratory. A description of the test and a demonstration of its utility to resolve thermotolerance differences between close-by reef sites was published as an online early article on 21 June 2020 in the journal Global Change Biology.

The test system is highly mobile, can be deployed on boats, and is straightforward to use: Corals are placed in test boxes at the location where they were collected and then subjected to thermal exposures at different temperatures -- a type of stress test for the corals. Using a standardized procedure, researchers can then record the results and compare how different corals react to the same set of temperature exposures.

"We focused on building the test boxes with materials that are available in almost any hardware store or shop selling aquarium equipment. We want these test boxes to be used widely and this is why we made all instructions for setting up the tests as well as our results and evaluation methods freely available," Professor Christian Voolstra states in reference to the online archive: https://github.com/reefgenomics/CBASSvsCLASSIC

Story Source:

Materials provided by University of Konstanz. Original written by Jürgen Graf. Note: Content may be edited for style and length.

Journal Reference:
Christian R. Voolstra, Carol Buitrago‐López, Gabriela Perna, Anny Cárdenas, Benjamin C. C. Hume, Nils Rädecker, Daniel J. Barshis. Standardized short‐term acute heat stress assays resolve historical differences in coral thermotolerance across microhabitat reef sites. Global Change Biology, 2020; DOI: 10.1111/gcb.15148

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University of Konstanz. "Stress testing 'coral in a box'." ScienceDaily. ScienceDaily, 8 July 2020. .