Friday, September 23, 2022

A sarbecovirus found in Russian bats is capable of using human ACE2 to enter cells, and is resistant to the antibodies of people vaccinated against SARS-CoV-2

Peer-Reviewed Publication

PLOS

A sarbecovirus found in Russian bats is capable of using human ACE2 to enter cells, and is resistant to the antibodies of people vaccinated against SARS-CoV-2 

IMAGE: RESEARCHERS ASSESSED A SARBECOVIRUS THAT IS FOUND IN RUSSIAN LESSER HORSESHOE BATS AND CAPABLE OF USING HUMAN ACE2 TO ENTER CELLS, AND IS RESISTANT TO THE ANTIBODIES OF PEOPLE VACCINATED AGAINST SARS-COV-2. view more 

CREDIT: JOÃO MANUEL LEMOS LIMA, WIKIMEDIA COMMONS (CC-BY 4.0, HTTPS://CREATIVECOMMONS.ORG/LICENSES/BY/4.0/)

A sarbecovirus found in Russian bats is capable of using human ACE2 to enter cells, and is resistant to the antibodies of people vaccinated against SARS-CoV-2

 

Article URL: http://journals.plos.org/plospathogens/article?id=10.1371/journal.ppat.1010828

Article Title: An ACE2-dependent Sarbecovirus in Russian bats is resistant to SARS-CoV-2 vaccines

Author Countries: United States

Funding: This work was supported by WSU and the Paul G. Allen School for Global Health (ML BG, SNS, SF, SB). Funding for the clinical study specimens was provided under NIH Project U54CA260581-01 (JR, KZ, EN) The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Hunga Tonga-Hunga Ha’apai Eruption blasted vast quantities of water vapor into the stratosphere

Peer-Reviewed Publication

AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE (AAAS)

The explosive eruption of the underwater volcano Hunga Tonga-Hunga Ha’apai in January 2022 injected at least 50 million metric tons of water vapor directly into the stratosphere, potentially increasing the amount of global stratospheric water vapor by more than 5%, according to a new study. The findings suggest that this event has likely initiated an atmospheric response different from that of previous well-studied large volcanic eruptions. Although rare, large volcanic eruptions can eject large amounts of gasses, ash and other particulates high into the atmosphere, where they can influence stratospheric chemistry and dynamics for several years following eruption. In addition to ash, sulfur-containing gasses are often considered the most important gases injected into the stratosphere and can result in a decrease in global climate temperature and accelerated ozone destruction. While it is thought that direct injection of water vapor could help moderate the climate impacts of volcanic aerosols, volcanic eruptions are generally not considered to be a major source for stratospheric water vapor. Even the largest eruptions over the past century have only resulted in minor water vapor injections. According to Holger Vömel and colleagues, however, the hydromagmatic eruption of Hunga Tonga-Hunga Ha’apai was quite different. Using in situ measurements from radiosondes carried aloft by high-altitude weather balloons, Vömel et al. show that this event injected a massive amount – at least 50 teragrams – of water vapor directly into the stratosphere, potentially increasing stratospheric water vapor by at least 5% on a global average. While the atmospheric impacts of this observationally unprecedented event remain uncertain, the authors suggest that the increased amounts of stratospheric water vapor could contribute to stratospheric cooling and surface warming over the months to come, and that these effects could persist longer than those caused by injected aerosols, which tend to drop out of the stratosphere through gravitational settling.







*Free* Dryland forestation lends limited climate change mitigation potential

Peer-Reviewed Publication

AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE (AAAS)

Despite being a promising and widely considered approach, a new study finds that forestation of Earth’s vast drylands would do little to slow climate change, researchers report. The findings show that although smart dryland forestation can be an important tool in some respects, its limited short-term climate benefits argue that it cannot be a substitute for rapidly reducing emissions. Growing forests sequester carbon. Leveraging this ability through forestation, which includes both afforestation to create new forests where there was no previous tree cover and reforestation to restore depleted forests, has been widely proposed as a promising approach to counteract increasing carbon emissions to mitigate ongoing global climate change. However, the actual climatic benefits of forestation are uncertain because increased tree coverage reduces the landscape’s albedo or its ability to reflect solar energy, which, depending on the scale, could result in local or global warming effects. This is particularly true for the dryland regions covering nearly 40% of the global land area where the albedo warming effect of afforestation could strongly outweigh any cooling effect from carbon sequestration as reflective desert land is converted to darker energy absorbing forest cover. To better understand the possible climatic benefits for dryland forestation, Shani Rohatyn and colleagues performed a high-resolution spatial analysis of global drylands and simulated the climatic effects of afforestion in these regions. Through their investigation, Rohatyn et al. identified 448 million hectares suitable for forestation and sequestration potential of more than 32 billion tons of carbon over the next 80 years. However, the authors found that this would do little to slow our warming climate. Accounting for the significantly decreased albedo in these regions, the authors show that the cooling effect of forestation of this vast area would only amount to that of a decrease of about 1% of projected greenhouse gas emissions under medium-emissions and business-as-usual climate scenarios. Despite this, Rohatyn et al. note that carefully planned and implemented dryland afforestation could provide other, more local benefits and potentially longer-term climate mitigation beyond their 80-year evaluation period.

It may already be too late to meet UN genetic diversity target, but new findings could guide conservation efforts

More than one-tenth of the world’s terrestrial genetic diversity may already be lost

Peer-Reviewed Publication

CARNEGIE INSTITUTION FOR SCIENCE

Rhino at risk 

IMAGE: ARTIST’S CONCEPT ILLUSTRATING THE RHINO'S DECREASING GEOGRAPHICAL RANGE AND LOSS OF GENETIC VARIABILITY. view more 

CREDIT: ARTWORK IS COURTESY OF MARK BELAN | ARTSCISTUDIOS.COM.

Palo Alto, CA—Climate change and habitat destruction may have already caused the loss of more than one-tenth of the world’s terrestrial genetic diversity, according to new research led by Carnegie’s Moises Exposito-Alonso and published in Science. This means that it may already be too late to meet the United Nations’ proposed target, announced last year, of protecting 90 percent of genetic diversity for every species by 2030, and that we have to act fast to prevent further losses.

Several hundred species of animals and plants have gone extinct in the industrialized age and human activity has impacted or shrunk half of Earth’s ecosystems, affecting millions of species.  The partial loss of geographic range diminishes population size and can geographically prevent populations of the same species from interacting with each other.  This has serious implications for an animal or plant’s genetic richness and their ability to meet the coming challenges of climate change.

“When you take away or fundamentally alter swaths of a species’ habitat, you restrict the genetic richness available to help those plants and animals adapt to shifting conditions,” explained Exposito-Alonso, who holds one of Carnegie’s prestigious Staff Associate positions—which recognizes early career excellence—and is also an Assistant Professor, by courtesy, at Stanford University.

Until recently, this important component has been overlooked when setting goals for preserving biodiversity, but without a diverse pool of natural genetic mutations on which to draw, species will be limited in their ability to survive alterations to their geographic range.

In popular culture, mutations convey super powers that defy the laws of physics. But in reality, mutations represent small, random natural variations in the genetic code that could positively or negatively affect an individual organism’s ability to survive and reproduce, passing down the positive traits down to future generations.

CAPTION

Infographic illustrating how loss of habitat is tied to loss of genetic diversity and extinction risk.

CREDIT

Illustration is courtesy of Mark Belan | artscistudios.com.

“As a result, the greater the pool of mutations upon which a species is able to draw, the greater the chances of stumbling upon that lucky blend that will help a species thrive despite the pressures created by habitat loss, as well as shifting temperature and precipitation patterns,” Exposito-Alonso added.

He and his collaborators set out to develop a population genetics-based framework for evaluating the richness of mutations available to a species within a given area.

They analyzed genomic data for more than 10,000 individual organisms across 20 different species to demonstrate that Earth’s terrestrial plant and animal life could already be at much greater risk from genetic diversity loss than previously thought. Because the rate at which genetic diversity is recovered is much slower than that at which it is lost, the researchers consider it effectively irreversible.

“The mathematical tool that we tested in 20 species could be expanded to make approximate conservation genetics projections for additional species, even if we don’t know their genomes,” Exposito-Alonso concluded. “I think our findings could be used to evaluate and track the new global sustainability targets, but there is still much uncertainty. We need to do a better job in monitoring populations of species and developing more genetic tools.”

“Moi took a bold, creative approach to probing a scientific question that’s crucial for policymakers and conservationists to understand if they want to implement strategies that will meet the coming challenges our world faces,” said Margaret McFall-Ngai, Director of Carnegie’s newly launched Divison of Biosphere Sciences & Engineering. “This kind of intellectual courage is illustrative of the Carnegie model of doing oustside-of-the-box science and the kind of work that is a hallmark of our prestigious Staff Associate program.”

The research team included members of Exposito-Alonso’s lab—Lucas Czech, Lauren Gillespie, Shannon Hateley, Laura Leventhal, Megan Ruffley, Sebastian Toro Arana, and Erin Zeiss—as  well as collaborators Tom Booker of the University of British Columbia; Christopher Kyriazis of UCLA; Patricia Lang, Veronica Pagowski, Jeffrey Spence, and Clemens Weiß of Stanford University; and David Nogues-Bravo of the University of Copenhagen.

__________________

This work was supported by a U.S. National Institutes of Health Early Investigator Award, the U.S. Department of Energy Office of Biological and Environmental Research, the Carnegie Institution for Science, Stanford’s Center for Computational Evolutionary and Human Genomics, a Human Frontier Science Program Long-Term Fellowship, and the U.S. National Science Foundation’s Plant Genome Postdoctoral Research Fellowship in Biology.

The Carnegie Institution for Science (carnegiescience.edu) is a private, nonprofit organization headquartered in Washington, D.C., with three research divisions on both coasts. Since its founding in 1902, the Carnegie Institution has been a pioneering force in basic scientific research. Carnegie scientists are leaders in the life and environmental sciences, Earth and planetary science, and astronomy and astrophysics.

Disclaimer: A

Toward a European carbon footprint rule for batteries

Focus on upstream production, not downstream use

Reports and Proceedings

ETH ZURICH

Top energy, tech, and climate researchers at ETH Zurich engaged in an informed debate over the European regulation that sets an upper carbon footprint limit for European markets. The limits, to be established this year, come into force in 2027 and will apply to electric vehicle batteries and stationary batteries with more than 2 kilowatt-hours (kWh) of storage capacity. Researchers anticipate that any throughput-based design option for quantifying the Carbon Footprints of batteries may fall short of its expectations and do more harm than good.

The regulation could play a pioneering role in climate change policy. Experience with it may also prove invaluable for non-European regulators and for the regulatory design of products that share characteristics with batteries. The European take on addressing the Carbon Footprint of complex, multipurpose technologies will, therefore, be closely observed internationally.

 

Villaseñor co-authors PNAS paper on extinction of megafauna

A study coauthored by Amelia Villaseñor shows that a megafaunal extinction in North America more than 10,000 years ago resulted in a reorganized, vulnerable ecosystem

Peer-Reviewed Publication

UNIVERSITY OF ARKANSAS

Amelia Villasenor.jpg 

IMAGE: AMELIA VILLASENOR, UNIVERSITY OF ARKANSAS view more 

CREDIT: RUSSELL COTHREN, UNIVERSITY OF ARKANSAS

Anthropologist Amelia Villaseñor coauthored a paper describing the ecological effects of an extinction event that occurred more than 10,000 years ago in North America, one that had major consequences for the surviving mammal species.

The paper, titled "Late Pleistocene megafauna extinction leads to missing pieces of ecological space in a North American mammal community,” was published in Proceedings of the National Academy of Sciences, or PNAS, a journal of the National Academy of Sciences.

“Our findings show that the extinction of large-bodied animals, like mammoths, substantially changed how the remaining mammal communities were organized,” Villaseñor said. “The findings also suggest that human impacts have likely played a major role in large-scale degradation of North American ecosystems for thousands of years.”

Villaseñor’s research uses the remains of fossil mammals to understand how humans and other animals interacted with each other over the last 3.5 million years, as well as the ecological impacts of extinction.

For this study, to gain a better understanding of modern biodiversity loss, she and colleagues relied on the fossil record of mammals from the Texas Memorial Museum that span roughly 50,000 years ago to recent times. These collections include extinct megafauna from Texas. Megafauna are large-bodied mammals such as mammoths and sabertooth cats.

The researchers characterized the roles of extinct and surviving mammals using stable isotopes and body size. Stable isotopes are present in all parts of an animal’s body, and certain kinds of isotopes can stay preserved for millions of years. They provided Villaseñor and her team with a record of animal diets and how those diets changed through time.

The researchers also estimated the body size of animals, which gave them another piece of information about how animals interacted with their environment and each other. Together, this information describes the job an animal has in its community or its “niche.”  

The team found that after the extinction, the surviving animal community was reorganized in what they ate and where they fell in the food chain, particularly among carnivores. Jaguars moved into a specialized dietary niche previously occupied by extinct cats like the sabertooth and the American lion. Puma, which were previously rare in the community, became common.

Biodiversity loss also led to “vacant niches,” or missing pieces, within the community, meaning that the roles of species such as mammoths, mastodons, and sabertooth cats were never again filled by the native mammal community. This biodiversity and ecological loss led to an overall reduction in ecosystem resilience that will affect the ability of native North American mammal communities to respond to future environmental changes.

The study’s lead author was Felisa Smith, biology professor at the University of New Mexico. In addition to Villaseñor, co-authors were Seth Newsome at the University of New Mexico, Emma Elliot Smith at the Smithsonian Institution and Kate Lyons and Catalina Tomé at the University of Nebraska-Lincoln.

Findings from this study support those of previous work published by Villaseñor this year in Nature Communications. The earlier study showed that mammal communities of North America have been homogenizing, or becoming more similar to one another, at faster rates over the last 10,000 years.

The earlier study also suggested lasting impacts from the megafaunal extinction on remaining mammal communities. Both studies showed that human impacts have likely played a major role in the reorganization and loss of resiliency of North American ecosystems for thousands of years.

The studies also have implications for the future.

“Our research of ancient mammals highlights what might happen if Earth’s remaining large-bodied mammals go extinct — animals such as elephants, rhinos, zebra, and lions — and it demonstrates how insights from the past can really inform modern conservation efforts,” said Smith.

Understanding the dynamics of workplace violence can improve employee health and safety


Peer-Reviewed Publication

UNIVERSITY OF TORONTO, ROTMAN SCHOOL OF MANAGEMENT

Prof. Katherine (Katy) DeCelles 

IMAGE: KATHERINE (KATY) DECELLES IS A PROFESSOR OF ORGANIZATIONAL BEHAVIOR AT THE UNIVERSITY OF TORONTO'S ROTMAN SCHOOL OF MANAGEMENT AND CROSS-APPOINTED TO THE CENTRE FOR CRIMINOLOGY AND SOCIOLEGAL STUDIES AT THE UNIVERSITY OF TORONTO. SHE ALSO HOLDS THE SECRETARY OF STATE PROFESSORSHIP IN ORGANIZATIONAL EFFECTIVENESS. KATY’S RESEARCH IS ON UNDERSTANDING THE MICRO-MECHANISMS INVOLVED IN CONFLICT, EMOTION, MORALITY, INEQUALITY, AGGRESSION, CRIME, AND CRIMINAL JUSTICE ORGANIZATIONS. HER RESEARCH HAS BEEN HIGHLIGHTED IN OUTLETS SUCH AS THE SMITHSONIAN MAGAZINE, SCIENCE MAGAZINE, BBC, CNN, AND THE NEW YORK TIMES. HER RESEARCH HAS RECEIVED AWARDS FROM THE ACADEMY OF MANAGEMENT AND AMERICAN SOCIOLOGICAL ASSOCIATION, AND SHE HAS BEEN RECOGNIZED FOR HER MBA TEACHING BY POETS & QUANTS (2018). view more 

CREDIT: ROTMAN SCHOOL OF MANAGEMENT

Toronto – Workplace violence is a pervasive problem with tremendous costs for individuals, organizations, and society. A new study published this week in the Proceedings of the National Academy of Sciences (PNAS) focuses on convenience-store robberies, one of the most common forms of workplace violence, and finds that robbers are significantly more likely to injure employees who are present on the sales floor rather than behind the cash register when a robbery begins. But industry standard safety training practices encourage employees to get out from behind the register for their safety.

“Unlike past studies, we used video of convenience-store robberies to examine why and when injuries during robberies occur,” says co-author Katherine DeCelles, a professor of organizational behavioural and human resource management at the University of Toronto’s Rotman School of Management, who hold a cross-appointment to the University’s Centre for Criminology and Sociolegal Studies. “We suggest that an understanding of the interactive dynamics of workplace violence and emphasize the critical need to verify that common practices for organizations are evidence based for employee health and safety.”

Prof. DeCelles and her colleagues first examined 196 surveillance videos and archival data of convenience store robberies collected over a four-year period. The results showed a significant correlation between employee location at the beginning of the robbery and injury, with lower risk of injury if employees were behind the register when the robbery began than if they were on the sales floor. Follow-up studies involving 648 people, including both formerly incarcerated individuals and retail clerks, found that when presented with robbery onset scenarios, more than 81% of participants expected employees to be behind the register and anticipated significantly more violence during the robbery if the employee was on the sales floor rather than behind the register. Finally, the authors conducted a three-year longitudinal field study with revised safety protocols that provided a behavioral script to follow in case of a robbery while employees are on the sales floor. The authors found, in an additional 368 robberies, a significantly lower risk of injury when employees were on the sales floor as the robbery began following the protocol change, relative to before the intervention.

 

“This understanding of the dynamics of workplace violence and how to mitigate it is relevant for any retail organization and for developing effective policies which promote employee health and safety,” says Prof. DeCelles.

The research was co-authored with Maryam Kouchaki of Northwestern University’s Kellogg School of Management and Nir Halevy of Stanford University’s Graduate School of Business.

Bringing together high-impact faculty research and thought leadership on one searchable platform, the new Rotman Insights Hub offers articles, podcasts, opinions, books and videos representing the latest in management thinking and providing insights into the key issues facing business and society. Visit www.rotman.utoronto.ca/insightshub.

The Rotman School of Management is part of the University of Toronto, a global centre of research and teaching excellence at the heart of Canada’s commercial capital. Rotman is a catalyst for transformative learning, insights and public engagement, bringing together diverse views and initiatives around a defining purpose: to create value for business and society. For more information, visit www.rotman.utoronto.ca

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For more information:

Ken McGuffin

Manager, Media Relations

Rotman School of Management

University of Toronto

E-mail:mcguffin@rotman.utoronto.ca

 

Docile raccoons are super learners and likely trash can criminal masterminds



Peer-Reviewed Publication

THE COMPANY OF BIOLOGISTS

Bustling with exciting urban opportunities, cities are attractive not only to human residents. Many creatures happily share human settlements, feasting on easy pickings. But what makes some creatures better suited for life in the urban fast lane? ‘Several cognitive abilities have been proposed as particularly important for urban wildlife’, says Lauren Stanton from the University of California, Berkeley, USA, including learning from situations and adapting to change. But no one had pinned down how one particularly successful urban colonist, the raccoon, has taken North American cities by storm. While studying for her PhD with Sarah Benson-Amram at the University of Wyoming, USA, Stanton, with Eli Bridge (University of Oklahoma, USA) and Joost Huizinga (OpenAI, USA), embarked on an ambitious program to get inside the heads of the urban mammals to find out what makes a great city dweller. The team publishes their discovery that the least bold and most docile animals are the best learners in Journal of Experimental Biology and suggest that targeting the boldest raccoons when there is human conflict could exacerbate the problem, as the most docile animals that remain are probably the true trash can raiding criminal masterminds.

‘We used live traps baited with cat food to humanely capture raccoons living in the city of Laramie, Wyoming’, says Stanton, who then transported the animals to the lab to assess their health and how feisty or docile they were. Then Stanton injected a tiny radio frequency ID tag between the animals’ shoulder blades to individually identify them before returning the animals to their home territories, keeping track of their impulsivity by recording each time an individual ended up in a trap again.

Having tagged 204 raccoons between August 2015 and September 2019, Stanton and the team then tested how well the wild raccoons learned and adapted to change by locating a raccoon-sized cubicle in the animals’ neighbourhood, equipped with two buttons: one that released a handful of tasty dog food treats when pressed, and a second one that provided nothing. However, once each raccoon had overcome its misgivings and learned to climb inside the cubicle and obtain its edible reward, the team turned the tables on the animals, switching which button dispensed the dog food reward, to find out how quickly the raccoons figured out the change. However, Stanton admits that she and her colleagues hadn’t factored in how popular the raccoon cubicle would be, with several animals often trying to crowd inside simultaneously, bumping and distracting the raccoon at the console as it tried to obtain its dog food treat.

After two patient years, 27 raccoons got the hang of visiting the cubicle, with 19 figuring out how to press the buttons to provide themselves with rewards, and 17 realising that they had to depress the other button when the team tried to outfox them. Initially, the youngest raccoons seemed the keenest to explore the experimental cubicle; however, the adults were better prepared for adversity when the researchers switched the console buttons. And when they checked the animals’ temperaments, the least bold and most docile raccoons seemed best prepared to learn how to operate the console, ‘which suggests a potential relationship between emotional reactivity and cognitive ability in raccoons’, says Stanton.

However, when the researchers compared how the raccoons in the Laramie suburbs coped, compared with the wild raccoons that tried out their paws in a peaceful lab, the captive animals seemed to pick up the test more readily, ‘likely because there were more distractions and interruptions during testing in the natural conditions’, says Stanton. And the team is keen to see wildlife managers dealing with troublesome urban raccoons learn from their experience, warning that going after more proactive, bold individuals may exacerbate problems, as the calmer, more docile individuals that are left may be the true criminal masterminds.

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IF REPORTING THIS STORY, PLEASE MENTION JOURNAL OF EXPERIMENTAL BIOLOGY AS THE SOURCE AND, IF REPORTING ONLINE, PLEASE CARRY A LINK TO:  https://journals.biologists.com/jeb/article-lookup/doi/10.1242/jeb.243726

REFERENCE: Stanton, L. A., Bridge, E. S., Huizinga, J. and Benson-Amram, S. (2022). Environmental, individual and social traits of free-ranging raccoons influence performance in cognitive testing. J. Exp. Biol. 225, jeb243726. doi:10.1242/jeb.243726.

DOI:10.1242/jeb.244806

Registered journalists can obtain a copy of the article under embargo from http://pr.biologists.com. Unregistered journalists can register at http://pr.biologists.com to access the embargoed content. The embargoed article can also be obtained from Kathryn Knight (kathryn.knight@biologists.com)[KK2] 

This article is posted on this site to give advance access to other authorised media who may wish to report on this story. Full attribution is required and if reporting online a link to https://journals.biologists.com/jeb is also required. The story posted here is COPYRIGHTED. Advance permission is required before any and every reproduction of each article in full from permissions@biologists.com.

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Ancient Maya cities were dangerously contaminated with mercury

Exposure to mercury may have posed health hazard for ancient Maya

Peer-Reviewed Publication

FRONTIERS

The cities of the ancient Maya in Mesoamerica never fail to impress. But beneath the soil surface, an unexpected danger lurks there: mercury pollution. In a review article in Frontiers in Environmental Science, researchers conclude that this pollution isn’t modern: it’s due to the frequent use of mercury and mercury-containing products by the Maya of the Classic Period, between 250 and 1100 CE. This pollution is in places so heavy that even today, it pose a potential health hazard for unwary archeologists.

Lead author Dr Duncan Cook, an associate professor of Geography at the Australian Catholic University, said: “Mercury pollution in the environment is usually found in contemporary urban areas and industrial landscapes. Discovering mercury buried deep in soils and sediments in ancient Maya cities is difficult to explain, until we begin to consider the archeology of the region which tells us that the Maya were using mercury for centuries.”

Ancient anthropogenic pollution

For the first time, Cook and colleagues here reviewed all data on mercury concentrations in soil and sediments at archeological sites across the ancient Maya world. They show that at sites from the Classical Period for which measurements are available –  Chunchumil in today’s Mexico, Marco Gonzales, Chan b’i, and Actuncan in Belize, La Corona, Tikal, Petén Itzá, Piedras Negras, and Cancuén in Guatemala, Palmarejo in Honduras, and Cerén, a Mesoamerican ‘Pompeii’, in El Salvador –mercury pollution is detectable everywhere except at Chan b’i.

Concentrations range from 0.016 ppm at Actuncan to an extraordinary 17.16 ppm at Tikal. For comparison, the Toxic Effect Threshold (TET) for mercury in sediments is defined as 1 ppm.

Heavy users of mercury

What caused this prehistoric mercury pollution? The authors highlight that sealed vessels filled with ‘elemental’ (ie, liquid) mercury have been found at several Maya sites, for example Quiriqua in Guatemala, El Paraíso in Honduras, and the former multi-ethnic megacity Teotihucan in Central Mexico. Elsewhere in the Maya region, archeologists have found objects painted with mercury-containing paints, mainly made from the mineral cinnabar.

The authors conclude that the ancient Maya frequently used cinnabar and mercury-containing paints and powders for decoration. This mercury could then have leached from patios, floor areas, walls, and ceramics, and subsequently spread into the soil and water.

"For the Maya, objects could contain ch’ulel, or soul-force, which resided in blood. Hence, the brilliant red pigment of cinnabar was an invaluable and sacred substance, but unbeknownst to them it was also deadly and its legacy persists in soils and sediments around ancient Maya sites," said co-author Dr Nicholas Dunning, a professor at the University of Cincinnati.

As mercury is rare in the limestone that underlies much of the Maya region, they speculate that elemental mercury and cinnabar found at Maya sites could have been originally mined from known deposits on the northern and southern confines of the ancient Maya world, and imported to the cities by traders.

Health hazards and the ‘Mayacene’

All this mercury would have posed a health hazard for the ancient Maya: for example, the effects of chronic mercury poisoning include damage to the central nervous system, kidneys, and liver, and cause tremors, impaired vision and hearing, paralysis, and mental health problems. It’s perhaps significant that one of the last Maya rulers of Tikal, Dark Sun, who ruled around 810 CE, is depicted in frescoes as pathologically obese. Obesity is a known effect of metabolic syndrome, which can be caused by chronic mercury poisoning.

More research is needed to determine whether mercury exposure played a role in larger sociocultural change and trends in the Maya world, such as those towards the end of the Classic Period.

Co-author Dr Tim Beach, a professor at the University of Texas at Austin, said: “We conclude that even the ancient Maya, who barely used metals, caused mercury concentrations to be greatly elevated in their environment. This result is yet more evidence that just like we live today in the ‘Anthropocene’, there also was a ‘Maya anthropocene’ or ‘Mayacene’. Metal contamination seems to have been effect of human activity through history.”  

BHP coal mine workers in Australian state set to vote on industrial action
Reuters | September 21, 2022 | 

Mount Arthur thermal coal mine in Australia. (Image courtesy of BHP.)

Workers at four mines of the BHP Mitsubishi Alliance (BMA), which owns Australia’s largest metallurgical coal fields, will vote on strike action over working conditions and job security, their union said on Wednesday.


The possibility of industrial action at some sites of BHP Group’s joint venture with a unit of Mitsubishi Corp in Australia’s Queensland state comes as prices slump due to weaker steel demand in China.

Coking coal futures on the Dalian Commodity exchange closed at 2,192.5 yuan on Sept. 20, down from a high of 3,741 yuan in March.

“We had 15 months of negotiations with BHP, then another three months of negotiations assisted by the Fair Work Commission, but BHP refuse to do the right thing,” Stephen Smyth, the Mining & Energy Union’s (MEU) Queensland president, said in a statement.

Mitsubishi Development and BHP, one of the world’s biggest miners, did not immediately respond to a request seeking comment.

BMA, owned 50:50 by BHP and Mitsubishi Development, is Australia’s largest producer and supplier of seaborne metallurgical coal. The alliance operates seven mines in central Queensland’s Bowen Basin as well as the Hay Point Coal Terminal.

Smyth said the union will fight to protect permanent jobs after a steady decline over the last decade. Talks have not reached the point of discussing wage hikes as the focus was on working conditions, especially on job security, he said.

The union filed an application to strike with Australia’s workplace regulator on Monday but a date has not yet been set for the vote, a union spokesperson said in an emailed response.

More than 2,000 workers across four of BMA’s seven mines come under the current employment agreement, the union said.

BHP’s Queensland coal operations, which also include two mines operated by the miner independently, produced 41 million tonnes of steel-making coal in fiscal 2021. This is roughly 4% of the global total, data from the International Energy Agency showed.

(By Lewis Jackson and Renju Jose; Editing by Richard Pullin)