Tuesday, October 11, 2022

Heart infection could be cause of death of Polish, US hero

Heart infection could be cause of death of Polish, US hero
Polish President Bronislaw Komorowski speaks during the unveiling of the 
Tadeusz Kosciuszko monument in Warsaw, Poland, Tuesday, Nov. 16, 2010. 
Medical and genetic experts in Poland say that a heart infection with common skin
 bacteria could have caused the 1817 death of Tadeusz Kosciuszko, a Polish and 
U.S. military leader and national hero. Credit: AP Photo/Alik Keplicz, File

Medical and genetics experts in Poland say that a heart infection caused by a common skin bacteria could have caused the 1817 death of Tadeusz Kosciuszko, a Polish and U.S. military leader and national hero.

The experts said last month they found the genome of the Cutibacterium acne in the wax, wood and linen that had long-term contact with the tissues of Kosciuszko's heart, which has been preserved. They said it could have led to endocarditis, or inflammation inside the heart, and to his death, aged 71, in Switzerland.

The team was led by Prof. Michał Witt, head of the human genetics institute at the Polish Academy of Sciences in Poznan and Dr. Tadeusz Dobosz of the Wroclaw Medical University. They took the samples for their  from a vessel where the heart is being kept, at the Royal Castle in Warsaw.

Under some conditions,  can attack the , including the , leading to very serious problems, Witt told Polish Radio Zet24.

He stressed that it's hard to say for sure what caused Kosciuszko's death but that their findings have led them to the "rationally based hypothesis" that it was the acne bacteria that caused the documented rapid deterioration of his health and death.

Previously,  or pneumonia were believed to have ended Kosciuszko's life. He was said to have developed a  and chills after he had fallen off his horse into a cold stream.

Born in 1746 in the then-Polish-Lithuanian Commonwealth, Kosciuszko fought as colonel of the Continental Army in the 1776 American Revolutionary War. A military engineer and architect, he designed and oversaw the construction of America's fortifications, including West Point.

Back to restless Poland, in 1794 he commanded an ill-fated uprising against the Russian Empire that was annexing some of Poland's lands. He spent his last years in Switzerland.

Pickled in 'cognac', Chopin's heart gives up its secrets

© 2022 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed without permission.

Monday, October 10, 2022

Megadroughts helped topple ancient empires. They're in Australia's past, with more to come

Megadroughts helped topple ancient empires. They're in Australia's past, with more to come
The Khmer Empire in Cambodia suffered decades-long dry periods.
Credit: Fred Nassar/Unsplash, CC BY

Most Australians have known drought in their lifetimes, and have memories of cracked earth and empty streams, paddocks of dust and stories of city reservoirs with only a few weeks' storage. But our new research finds over the last 1,000 years, Australia has suffered longer, larger and more severe droughts than those recorded over the last century.

These are called "megadroughts," and they're likely to occur again in coming decades. Megadroughts can last multiple decades—or even centuries—with occasional wet years offering only brief relief. Megadroughts can also be shorter periods of very extreme conditions.

We show megadroughts have occurred several times across every inhabited continent over the last two millennia. They've dealt profound damage to agriculture and increased fire risk, and have even contributed to toppling civilizations.

Unless we incorporate the full potential of Australian drought into our planning, management and design, their impacts on society and the environment will likely worsen in coming decades.

The role of climate change

Instrumental records only go back so far. In Australia, they cover only the last 120 years or so. Scientists can gauge local, yearly climate further back in time, by deciphering clues written in tree rings, corals, and buried ice (known as ice cores), among other archives.

To look at previous occurrences of megadroughts, we consolidated findings drawn from such datasets and a range of other long-term records.

Historically, droughts have been defined by rainfall deficits, and these deficits can be largely attributed to complex interactions between oceans and the atmosphere over a long time. For example, decades-long La Niña conditions have been linked to medieval droughts in North and South America.

In contrast, research suggests human-caused  is now playing a more important role in amplifying drought conditions, as rising global temperatures increase evaporation.

There is some uncertainty in  about the effect of climate change on rainfall at local and regional scales. However, climate change is putting places that have previously endured megadroughts—such as Australia—at an increased risk of megadroughts in future.

Megadroughts and collapsing civilizations

Currently, parts of the United States—including Arizona, Nevada and Utah—are in the throes of a megadrought, lasting some two decades. Historically, megadroughts have profoundly impacted societies and environments.

In the American southwest, megadroughts in the late 1200s likely contributed to the desertion of the Mesa Verde cliff dwellings. Likewise, the Hohokam peoples relied heavily on a canal system, and this dependence in a time of severe and extended drought may have contributed to their decline over the 14th and 15th centuries.

In Central America, a megadrought between 1149 and 1167 likely brought instability to the Toltec state. And a megadrought between 1514–1539 weakened the Aztec state just prior to Spanish conquest.

Europe and Asia have had their share of megadroughts, too. Research shows severe megadroughts in Asia in the 1300s and early 1400s quite likely helped cause the collapse of Cambodia's vast Khmer Empire.

Megadroughts in Australia

While many Australians may remember the severity of the Millennium Drought between 1997 and 2009, we found this drought wasn't actually particularly unusual. Megadroughts of the same or greater severity have occurred over the past 1,000 years across several parts of Australia, and were relatively common over much of eastern Australia.

This includes megadroughts between 1500 and the 1520s, and between the 1820s and 1840s. And while relatively short, a  between 1789 and 1795, coinciding with European invasion, included several years of severe . The year 1792 in particular was extremely dry over almost all of eastern Australia.

Western Australia's wheat belt is currently experiencing a decline in rainfall. This, too, isn't unusual compared to droughts there in the past. Tree rings in the region reveal that longer, more severe droughts occurred there six times in the last 700 years, including the years 1393–1407, 1755–1785, and 1889–1908.

Even in Tasmania, evidence suggests prolonged dry periods occurred in the latter part of the 16th century, with a shorter but more severe downturn from 1670–1704.

We need to be better prepared

Water management in Australia has relied on short instrumental data. These do not capture the full range of variability in our rainfall.

This means, for example, that Australia's infrastructure may be inadequately designed or managed to cope with major flood events or prolonged dry conditions.

Now, even relatively short but very dry periods can lead to major problems. We saw this recently in Tasmania in the summer of 2015 and 2016 when, after a dry winter and spring,  in major catchments were minimal and fires raged in the west. The Basslink cable, which connects Tasmania to the national grid, broke, resulting in the use of diesel power generation to keep power on in the state.

Future megadroughts will amplify the pressures on already degraded Australian ecosystems. We know from Australia's recent past the harm relatively smaller droughts can impose on the environment, the economy, and our mental and physical health.

We must carefully consider whether current management regimes and water infrastructure are fit-for-purpose, given the projected increased frequency of megadroughts.

It's difficult to plan effectively without fully understanding even natural variability. And this means better appreciating the data we have from archives such as , corals and ice cores—crucial windows to our distant past.Historical review shows megadroughts could become permanent in some places due to climate change

Provided by The Conversation 

This article is republished from The Conversation under a Creative Commons license. Read the original article.The Conversation

Modern pesticide accelerates corrosion of ancient Roman bowl

Archaeology: Modern pesticide accelerates corrosion of ancient Roman bowl
The recent history of the Roman Bowl–(A) the area where the bowl was found in relation to other Roman sites, exact findspot cannot be shown to protect the site (B) the interior and (C) exterior of the bowl during conservation and (D) the bowl on display at Sandwich Museum. Credit: Scientific Reports (2022). DOI: 10.1038/s41598-022-17902-9

A corroded Roman bowl dated to the Late Iron Age (between 43 and 410 AD) contains traces of chlorobenzenes, a chemical once used in pesticides that is known to accumulate in soil and water sources. The study, published in Scientific Reports, highlights that soil polluted with chlorobenzenes may pose a continuing threat to the preservation of archaeological material still in the ground

Chlorobenzenes are  that can be toxic at high levels and most have been prohibited for use in the UK following concerns being raised about . These compounds are thought, however, to have accumulated in the environment through previous agricultural and industrial activities. A Roman bowl, made of a copper-alloy, was found in 2016 on a farm in Kent (UK), a site that was known to have been used for agriculture since at least 1936.

Luciana da Costa Carvalho and colleagues analyzed the green and brown-colored corrosion on the bowl to identify their different components. They found elements that were indicative of the changes over time in the soil caused by human activities. In the green-colored corrosion, the authors found chlorobenzenes were present. The authors also found diethyltoluamide (also known as DEET) in the brown-colored corrosion, a modern compound that is still used in .

The authors suggest that the chlorobenzenes were associated with increased corrosion in the Roman bowl. They conclude that even though chlorobenzenes are no longer used in the UK, polluted soil may still threaten the preservation of archaeological material still buried and more research needs to be undertaken to better understand the processes involved.Study reveals corrosion mechanism of magnesium alloys in marine atmospheric environment


More information: Luciana da Costa Carvalho, The influence of pesticides on the corrosion of a Roman bowl excavated in Kent, UK, Scientific Reports (2022). DOI: 10.1038/s41598-022-17902-9
Journal information: Scientific Reports 
Provided by Nature Publishing Group 

SEXISM IN SCIENCE

Just 20% of climate change studies are 'written by women'

Just 20% of climate change studies ‘written by women’
Professor Chioma Blaise Chikere at work. Credit: SciDev.Net’

Chioma Blaise Chikere is at the pinnacle of her career, as a professor of environmental microbiology and biotechnology at the University of Port Harcourt in Nigeria and director of the institution's Entrepreneurial Center.

Yet in this part of the world, such an achievement by a female scholar can be misleading.

Peel away the trappings that come with her office and you reveal a litany of struggles, obstacles and stereotypes that continue to dog the careers of many women scientists from the global South.

"My dream of becoming a world-class scientist was slipping through my fingers due to lack of funds," Chikere says of her earlier struggles. "My journey during early career days as a researcher and scientist was seriously limited by lack of access to educational resources for internationalization."

From a lack of access to standard scientific equipment and laboratories, to inadequate mentorship and scholarship opportunities, Chikere's career progression was in serious doubt.

Her story mirrors that of many researchers from the global South who still struggle to be on par with their counterparts in the North in terms of funding, collaboration and publishing—with negative impacts on .

"If there were biases in knowledge, then those biases translated themselves into innovations, creativity and development," says Elizabeth Pollitzer, the founder and director of Portia, a non-profit organization established to advance understanding of gender issues in science.

"Research shows that when you have a  in a team, the collective intelligence of that team goes up. We need this diversity of cognitive approaches and problem solving."

Climate of exclusion

Despite progress on gender representation in science and research in recent decades, disparities still exist. Women author fewer of the papers that are published in journals than men, and higher numbers of women leave research, according to the findings by the scientific publisher Elsevier.

Just 20% of climate change studies ‘written by women’

The  is particularly prevalent in . Only about 20% of published climate change research was attributed to female authors, according to an analysis by the International Center for the Study of Research, published in Scopus, Elsevier's abstract and citation database.

It considered research output data between 1996 and 2020, and showed that nearly 80% of all climate change research was attributed to men.

Regionally, the global North still dominated the climate change research landscape, accounting for more than 80% of all research in the past two decades—and this global share rises to more than 90% if China is excluded from the list of global South countries.

Pollitzer condemns "a culture that excludes women," adding, "Even when you have enough women in the talent pool, it's the men who will be invited to join research teams.

"Something strange happens where women appear to be systematically excluded."

Research funders, academic institutions and publishing firms must make deliberate efforts to increase the visibility of women researchers from the global South, Pollitzer says.

Visibility gaps

Chikere is one example of how institutional support can benefit the careers of women scientists.

The opportunity for Chikere came in 2017 after she applied for the Chemistry for Climate Action Challenge, a competition jointly run by the Elsevier Foundation—part of the corporate responsibility program of global publishing body Elsevier—and Elsevier's chemistry journals team. The challenge recognizes individuals and organizations whose projects use green and sustainable chemistry solutions to tackle the developing world's greatest sustainability challenges.

Chikere was awarded second prize at the finals in Berlin, Germany. Her project entailed eco-friendly field-scale clean-up of an oil-polluted site in Tombia village in the Degema local government area in Nigeria.

Just 20% of climate change studies ‘written by women’

The project, which involved use of poultry droppings as bio-stimulants and soil conditioners to enhance hydrocarbon removal, embraced circular economy, citizen science, indigenous knowledge and integrated waste management.

Earlier, Chikere acquired a Ph.D. fellowship by the Organization for Women in Science for the Developing World (OWSD). The Elsevier Foundation collaborates with OWSD to address visibility issues among women researchers through awards and recognition programs for talented early career women scientists from Africa, the Arab region, the Asia Pacific, and Latin America and the Caribbean.

"The Chemistry for Climate Action Challenge and other gender-based initiatives that encourage and support women scientists in the developing world to build their capacities in research need to be encouraged," Chikere says.

"I can say the support from Elsevier Foundation has greatly enhanced my career trajectory."

Bridging the gap

Nitya Rao, director of the Norwich Institute for Sustainable Development (NISD), a member of the global research group the Adaptation of Research Alliance (ARA), says gender gaps in climate change research persist because of a lack of understanding of gender.

She says existing gender training is often reduced to women's issues and there is a need to look at the wider factors which underpin gender disparity.

"The gaps can be bridged if we make changes in different elements of research cycle," says Rao, gender and development professor at the University of East Anglia's School of International Development.

"From identification of the research question/problem, to the methods of data collection, analysis and writing, often gender monitoring and evaluation focus only on numbers—men and women who have attended meetings, or are co-authors of papers. We need to go beyond this."

Sheela Patel, founder and director of the Society for the Promotion of Area Resource Centers (SPARC), an India-based NGO focusing on the urban poor, says the criteria for researcher selection needs to change.

"So long as it's the number of research papers published [which] remains the criteria for who to invite to do research, then  will always be disadvantaged, as highlighted by the latest data on  output."

'Prestigious' author rights go to men in health studies
Provided by SciDev.Net

Daytime pastoralist activities do not negatively affect spotted hyenas in Tanzania


Daytime pastoralist activities do not negatively affect spotted hyenas in Tanzania
Spotted hyena with Maasai pastoralist and cattle in Ngorongoro Crater.
 Credit: Oliver Höner/Leibniz-IZW

Pastoralists herding their livestock through the territories of spotted hyena clans along dedicated paths during daytime do not reduce the reproductive performance of hyena clans, nor elevate the physiological "stress" of spotted hyenas. This is the result of a new study led by scientists from the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW) and the Ngorongoro Conservation Area Authority (NCAA).

The scientists analyzed 24 years of demographic and  from eight  clans—two of which were exposed to activities by pastoralists. The activities of pastoralists were predictable, diurnal and did not disrupt important behaviors in the mostly nocturnal . This may have allowed the population to perform well, the scientists suggest. The open access paper is published in the Journal of Animal Ecology.

Human activities can strongly affect wildlife but the effects can vary greatly, depending on the type of activity and the characteristics of the wildlife species involved. To promote human-wildlife coexistence, it is therefore important to assess which activities are sustainable for a given species.

Most past research has documented major changes in the behavioral response of such species to human activities, but did not examine whether such changes are indicative of the Darwinian fitness of wildlife (in terms of its survival and reproductive success) or physiological effects such as "stress" or allostatic load, which are much more relevant to conservation.

"Acquiring the long-term data for such research—especially on large, group-living carnivores, which may be particularly conflict-prone—is not easy because of the enormous financial and temporal demands involved. We assessed for the first time the Darwinian fitness and the physiological effects of a common human activity—livestock herding—in light of the biology and social system of our wildlife species," explains first author Arjun Dheer, doctoral student at the Leibniz-IZW.

The investigation was conducted on eight clans of spotted hyenas (Crocuta crocuta) living in the Ngorongoro Crater, a UNESCO World Heritage Site in northern Tanzania. "Livestock grazing and using mineral licks occurred predictably on a near-daily basis within the territories of two of our eight study clans between 1996 and 2016," adds Dheer.

This created a natural experiment of exposed and unexposed clans which the scientists exploited. "We tested whether the hyenas of the exposed clans had fewer surviving offspring than the unexposed hyenas and whether the herding activities increased the physiological 'stress' of the hyenas," explains Dr. Oliver Höner (Leibniz-IZW), head of the Ngorongoro Hyena Project and senior author of the paper.

To assess the fitness effects, the scientists used 24 years of detailed demographic data from the eight clans and to estimate physiological stress, they measured the concentration of glucocorticoid metabolites (fGMC) in 975 feces from 475 hyenas. The team also accounted for the effects of additional ecological parameters such as disease outbreaks and the abundance of African lions (Panthera leo), the hyenas' main competitor, and prey.

The main result was that hyena clans exposed to Maasai pastoralists moving through their territory with their livestock had similar juvenile recruitment and fGMC levels as unexposed clans. "Our results suggest that the hyenas in the Ngorongoro Crater coped well with daytime pastoralism," explains Dheer. A likely explanation for the lack of detectable effect on hyenas is that the activity was predictable and minimally disruptive because it occurred during daytime.

"Hyenas are mostly nocturnal when it comes to critical behaviors such as hunting," explains Höner. Even if pastoralist activities forced other critical hyena behaviors such as the nursing of young cubs into nighttime, it might not have been too much of an adjustment for them to make. "Spotted hyenas are behaviourally flexible. In other areas, they were observed to move their cubs to dens further away from the paths that pastoralists used, or to nurse more at night," Höner says.

The authors caution that such results should not be extrapolated in uncritical fashion. "In areas where pastoralism is more intense and environmental conditions such as the abundance of wild prey are less favorable than in the Ngorongoro Crater, pastoralist activities may well have a significant detrimental effect even on a behaviorally highly flexible species such as the spotted hyena," explains Höner.

"Our investigation highlights the need to develop evidence-based coexistence strategies within a local context to benefit both stakeholders and wildlife. It also underscores the importance of interpreting the effects of human activity in light of the socio-ecology of the species of conservation interest," concludes Victoria Shayo (Head, Department of Wildlife and Rangeland Management, Ngorongoro Conservation Area Authority). Additional scientific analyses that cover a variety of anthropogenic activities and species—and that measure effects on fitness and physiology—will be conducive to promoting human-wildlife coexistence.Emotions and culture are most important for acceptance of carnivore management strategies

More information: Arjun Dheer et al, Diurnal pastoralism does not reduce juvenile recruitment nor elevate allostatic load in spotted hyenas, Journal of Animal Ecology (2022). DOI: 10.1111/1365-2656.13812
Journal information: Journal of Animal Ecology 

WEAPON OF THE JR. ANTI-SEX LEAGUE

Gonorrhea became more drug resistant during COVID-19. A molecular biologist explains the sexually transmitted superbug

Gonorrhea became more drug resistant during COVID-19—a molecular biologist explains the sexually transmitted superbug
Credit: CDC

COVID-19 has rightfully dominated infectious disease news since 2020. However, that doesn't mean other infectious diseases took a break. In fact, U.S. rates of infection by gonorrhea have risen during the pandemic.

Unlike COVID-19, which is a , gonorrhea is an ancient disease. The first known reports of gonorrhea date from China in 2600 BC, and the disease has plagued humans ever since. Gonorrhea has long been one of the most commonly reported bacterial infections in the U.S.. It is caused by the bacterium Neisseria gonorrhoeae, which can infect mucous membranes in the genitals, rectum, throat and eyes.

Gonorrhea is typically transmitted by . It is sometimes referred to as "the clap."

Prior to the pandemic, there were around 1.6 million new gonorrhea infections each year. Over 50% of those cases involved strains of gonorrhea that had become unresponsive to treatment with at least one antibiotic.

In 2020, gonorrhea infections initially went down 30%, most likely due to pandemic lockdowns and social distancing. However, by the end of 2020—the last year for which data from the Centers for Disease Control and Prevention is available—reported infections were up 10% from 2019.

It is unclear why infections went up even though some social distancing measures were still in place. But the CDC notes that reduced access to health care may have led to longer infections and more opportunity to spread the disease, and  may have increased when initial shelter-in-place orders were lifted.

As a molecular biologist, I have been studying bacteria and working to develop  to treat  for 20 years. Over that time, I've seen the problem of antibiotic resistance take on new urgency.

Gonorrhea, in particular, is a major public health concern, but there are concrete steps that people can take to prevent it from getting worse, and new antibiotics and vaccines may improve care in the future.

How to recognize gonorrhea

Around half of gonorrhea infections are asymptomatic and can only be detected through screening. Infected people without symptoms can unknowingly spread gonorrhea to others.

Typical early signs of symptomatic gonorrhea include a painful or burning sensation when peeing, vaginal or penal discharge, or anal itching, bleeding or discharge. Left untreated, gonorrhea can cause blindness and infertility. Antibiotic treatment can cure most cases of gonorrhea as long as the  is susceptible to at least one antibiotic.

There is currently only one recommended treatment for gonorrhea in the U.S.—an antibiotic called ceftriaxone—because the bacteria have become resistant to other antibiotics that were formerly effective against it. Seven different families of antibiotics have been used to treat gonorrhea in the past, but many strains are now resistant to one or more of these drugs.

Why gonorrhea is on the rise

A few factors have contributed to the increase in infections during the COVID-19 pandemic.

The CDC tracks the emergence and spread of drug-resistant gonorrhea strains.

Early in the pandemic, most U.S. labs capable of testing for gonorrhea switched to testing for COVID-19. These labs have also been contending with the same shortages of staff and supplies that affect medical facilities across the country.

Many people have avoided clinics and hospitals during the pandemic, which has decreased opportunities to identify and treat gonorrhea infections before they spread. In fact, because of decreased screening over the past two and a half years, health care experts don't know exactly how much antibiotic-resistant gonorrhea has spread.

Also, early in the pandemic, many doctors prescribed antibiotics to COVID-19 patients even though antibiotics do not work on viruses like SARS-CoV-2, the virus that causes COVID-19. Improper use of antibiotics can contribute to greater drug resistance, so it is reasonable to suspect that this has happened with gonorrhea.

Overuse of antibiotics

Even prior to the pandemic, resistance to antibiotic treatment for bacterial infections was a growing problem. In the U.S., antibiotic-resistant gonorrhea infections increased by over 70% from 2017–2019.

Neisseria gonorrhoeae is a specialist at picking up new genes from other pathogens and from "commensal," or helpful, bacteria. These helpful bacteria can also become antibiotic-resistant, providing more opportunities for the gonorrhea bacterium to acquire resistant genes.

Strains resistant to ceftriaxone have been observed in other countries, including JapanThailand, Australia and the U.K., raising the possibility that some gonorrhea infections may soon be completely untreatable.

Steps toward prevention

Currently, changes in behavior are among the best ways to limit overall gonorrhea infections—particularly safer sexual behavior and condom use.

However, additional efforts are needed to delay or prevent an era of untreatable gonorrhea.

Scientists can create new antibiotics that are effective against resistant strains; however, decreased investment in this research and development over the past 30 years has slowed the introduction of new antibiotics to a trickle. No new drugs to treat gonorrhea have been introduced since 2019, although two are in the final stage of clinical trials.

Vaccination against gonorrhea isn't possible presently, but it could be in the future. Vaccines effective against the meningitis bacterium, a close relative of gonorrhea, can sometimes also provide protection against gonorrhea. This suggests that a gonorrhea vaccine should be achievable.

The World Health Organization has begun an initiative to reduce gonorrhea worldwide by 90% before 2030. This initiative aims to promote safe sexual practices, increase access to high-quality  for sexually transmitted diseases and expand testing so that asymptomatic infections can be treated before they spread. The initiative is also advocating for increased research into vaccines and new antibiotics to treat gonorrhea.

Setbacks in fighting drug-resistant  during the COVID-19  make these actions even more urgent.

Scientists develop test to identify best treatment for gonorrhea

Provided by The Conversation 

This article is republished from The Conversation under a Creative Commons license. Read the original article.





 








Climate risk index shows threats to 90% of the world's marine species

Climate risk index shows threats to 90% of the world's marine species
The biodiversity-rich Komodo Island in Indonesia is a climate risk hotspot.
Daniel G. Boyce, Author provided

Climate change impacts marine life through a bewildering web of complex pathways.

Warming oceans and  are driving species into deeper, more northern and cooler locations, altering their behavior and reconfiguring marine ecosystems in radical and unprecedented ways.

While some impacts can be beneficial, many are harmful, making it difficult to understand the overall effects of climate on  and ecosystems. Despite these challenges, we urgently need to understand how changing  affect marine life to plan and develop adaptation approaches to steward it effectively under .

In our new study, my co-authors and I developed the Climate Risk Index for Biodiversity, which captures the climate risk for nearly 25,000  and their ecosystems. This new index lays the groundwork for supporting climate-smart approaches to managing and conserving marine life.

A climate report card

We used a data-driven statistical approach to create a "climate report card" for each species and ecosystem that tells us which ones will win or lose under climate change. This approach enabled us to study a broad spectrum of life forms, from microscopic plankton to  and whales, across all  from the tropics to the poles.

Just as a report card grades students on subjects such as math and science, we assessed each species on 12 specific climate risk factors depending on two different future scenarios—one with lower emissions and one with higher emissions.

The climate risk factors express how the innate characteristics of a species—their body size and temperature tolerance—intersect with past, present and future ocean conditions at all locations where they are found.

The resulting risk scale ranges from negligible (lowest) to critical (highest) and represents both the severity of harmful climate impacts on species and their likelihood of occurring.

Divergent climate futures

Our study focuses on two possible shared socioeconomic pathway scenarios of how future society—and the  it produces—could transpire. The results paint two wildly divergent pictures for marine life and people.

In the high emissions scenario, the global average ocean temperature will increase by three to five degrees Celcius by 2100. Under this scenario, almost 90% of the 25,000 species we assessed were at a "high" or "critical" climate risk. The average species was at risk across 85% of its geographic range.

Climate risk index shows threats to 90% of the world's marine species
The proportion of marine species at high or critical climate risk under high emissions by 2100. Darkest red shading denotes the highest risk areas, and darkest blue the lowest. Credit: Daniel G. Boyce

The risk is highest in the subtropical and tropical ecosystems that tend to be biodiversity hotspots and in nearshore ecosystems that support 96% of the global fish catch.

Top predators like sharks and tunas were at significantly higher risk than species further down the food chain, like forage fishes. Such predators can have massive effects on ecosystem structure and functioning.

Our findings also suggest severe ripple effects for people who most rely on the ocean. Under high emissions, climate risks for fished species such as cod and lobsters were consistently greater within the territories of low-income nations, where people depend more on fisheries to meet their nutritional needs.

This represents yet another example of climate inequality wherein low-income countries that have contributed the least to climate change, and are more aggressively reducing their emissions, are experiencing its worst impacts while having the lowest capacity to adapt to them.

Our study stresses that we are at a critical fork in the road and that choosing a more sustainable path that prioritizes climate mitigation will lead to clear benefits for ocean life and people.

Under a low emissions scenario, average ocean temperatures are expected to increase by one to two degrees Celsius by 2100, as per the two degrees Celsius global warming limit in the Paris Agreement.

Under this future, we found a reduced climate risk for virtually all marine life (98.2%). The disproportionate risk for ecosystem structure, biodiversity, fisheries and low-income nations are greatly reduced or eliminated.

Averting harmful climate risks

Our approaches to fisheries managementprotected area planning and biodiversity conservation originated in a world with a relatively stable climate. But climate change is rewriting the rule books and threatening to undermine the effectiveness of these traditional approaches.

Cutting emissions is the most direct approach to reducing climate risks. Yet, even with strong mitigation, our study suggests that climate change will continue to affect marine life.

In addition to reducing emissions, it is imperative that we simultaneously find ways to adapt to a warming climate to protect our oceans. We must incorporate new methods and adaptation strategies, develop capacity in under-resourced parts of the world and carefully weigh the pros and cons of adaptation measures.

Our study provides a new tool and index to help inform decision-makers when navigating these complex issues. It can assist with developing strategies to manage and conserve marine life under climate change, monitor changing  and gauge progress towards risk reduction.

While our study paints a potentially grim future under high emissions, it also highlights how our oceans and  could benefit from climate change mitigation and adaptation and stresses the urgency with which we must work towards this goal.Study shows 90% of marine species at risk of extinction by 2100 if greenhouse gas emissions are not curbed

Provided by The Conversation 

This article is republished from The Conversation under a Creative Commons license. Read the original article.The Conversation

On How US Hegemony Built Spaceship Earth: Marija Radovanovic

Planetary Justice

#worldecology #capitalocene

Marija Radovanovic, Department of Sociology and World-Ecology Research Group, Binghamton University. 

Seventh Annual Conference of the World-Ecology Research Network: Imperialism and Anti-Imperialism in the Web of Life, 23  October, 2021

Buckminster Fuller at MIT - Spaceship Earth - 1979