An exploratory study led by extremism expert Dr Jared Dmello, from the University of Adelaide’s School of Social Sciences, found some climatological variables affected terrorist activity in India.

“Suitability analyses indicate that all the climatological variables tested — temperature, precipitation, and elevation — relate to shifting patterns of terrorist activity,” says Dr Dmello.

“Urban centres have increasingly grown in population density, particularly in spaces with favourable climates, and some of the more remote areas once used by extremists have experienced such increasingly dynamic climates that they are no longer fit for human habitation, forcing these groups to migrate elsewhere.”

It was not only the intensity of these climatological variables that led to terrorists moving to new locales, this shifting of terrorist activity was also seasonal.

“This research shows that stopping the damaging effects of climate change is not just an environmental issue but one that is directly tied to national security and defence,” says Dr Dmello, who was recently announced as the inaugural recipient of the Early Career Award from the Academy of Criminal Justice Sciences’ Security and Crime Prevention Section.

“In this study, we focus on attack location, but the data also suggests other forms of extremist behaviour, such as training location, are likely shifting in response to climate change as well.”

The study, published in the Journal of Applied Security Research, concentrated on terrorist activity in India between 1998-2017, a period during which there were 9096 terrorist incidents recorded by the Global Terrorism Database.

“Average temperatures in India reached record highs during our 20-year study period,” said Dr Dmello.

“This time frame represents a broad enough range to demonstrate climate change, while also availing of the most recent reliable data that covers both the climate change and extremism dimensions for the country.”

This new and evolving understanding of how climate change affects patterns of terrorism is important knowledge for governments across the world, including Australia’s, to inform national security and defence strategies.

“While terrorism and violent extremism manifests differently in Australia, with far lower levels of attacks than India, radicalisation is still a salient challenge here and one that the Australian Government has established as a national priority,” says Dr Dmello.

“To effectively mitigate radicalisation, other critical issues, such as homelessness, food insecurity, water and energy crises, and enhanced social equity, are essential for ensuring a more secure space for us all.”

Dr Dmello, who joined the University of Adelaide at the beginning of 2024, also recently co-edited a book examining security in the Arctic from a multi-disciplinary lens and will continue his research into terrorism and extremism in the Australian context.

“Some of my recent projects have been trying to understand how emerging issues impact radicalisation here in Australia in an effort to find ways to partner with government and law enforcement to prevent engagement with extremist ideologies,” he says.

“I am also interested in expanding on my research in this area to investigate the role of water and food inequities on radicalisation around the world.”

“Society is facing a slew of global challenges, and we wanted to assess the extent to which higher education is contributing to the sort of transformative change needed to address these challenges,” says Christopher Galik, co-author of the study and a professor of public administration at North Carolina State University. “For this study, we started at the local level, exploring whether there was any association between university sustainability performance and sustainability in their surrounding communities.”

To explore the issue, researchers looked at data from 105 metropolitan areas in the United States, which are collectively home to 427 higher education institutions. Specifically, the researchers drew on data from two sources, the U.S. Cities Sustainable Development Goal (SDG) Index and the QS Sustainability Universities Ranking.

The SDG Index aggregates dozens of metrics related to a municipality’s sustainability efforts, covering issues such as climate action, energy efficiency and water use. The QS Sustainability Universities Ranking evaluates university efforts related to environmental sustainability as well as efforts aimed at addressing social concerns, such as global partnerships, community engagement and the health and well-being of students, faculty and staff.

The researchers wanted to see whether there was any relationship between universities that scored well on the QS Sustainability Universities Ranking and the municipalities that scored well on the SDGs.

“Sustainability is complicated — it has lots of different components,” says Ha Vien, first author of the paper and a Ph.D. student at North Carolina State University. “And we found that universities are associated with progress on some of those measures, but not others.”

The good news is that there was a very strong correlation between universities that score well on sustainability and communities that score well on innovation, reducing poverty, creating economic opportunities and reducing inequality.

“The bad news is that universities that perform strongly on sustainability measures are also associated with a decline in responsible consumption and production — measured here as increased air pollution and release of toxic chemicals — in their surrounding areas,” Vien says. “There was also little or no correlation between universities that scored well on environmental sustainability and the environmental sustainability scores of their communities.”

“This is an observational study, so it’s impossible to determine causation,” Galik says. “However, the evidence suggests two things. First, universities continue to be strongly associated with innovation and economic development. But second, the idea that universities can contribute to broader sustainable transformations doesn’t seem to be realized yet, at least on a large scale.”

“It took significant time and effort for universities to become the economic drivers that we see today,” Vien says. “Looking into the future, climate change will continue to be a defining challenge for the foreseeable future. Our findings highlight that there are still a lot of opportunities for higher education to make more of a difference in surrounding communities.”

Single-use plastic straws are an environmental problem that few people think about. But consider the popularity of drinks like fountain sodas, iced lattes and bubble teas; all the accompanying plastic straws add up to a lot of plastic waste.

According to Australian researchers, as many as 8.3 billion plastic straws litter the world’s beaches, roughly one for every living human. Those straws are difficult to recycle and seldom accepted by curbside programs or at transfer centers, but most importantly they add to the plastic catastrophe happening in our oceans.

By switching to a reusable, you’ll reduce the demand for single-use polypropylne (#5 plastic) straws, the manufacturing of which produces about 1.5 grams of CO2 emissions. That may not sound like much, but the approximately 500 million straws used in the U.S. each day account for 1.6 million pounds of CO2 emissions — 301,757.36 tons annually.

The good news is that there are lots of practical alternatives to the single-use plastic straw, including the nine options below.

Note: This post contains affiliate links, which helps fund our Recycling Directory, the most comprehensive in North America.

1. Reusable Plastic

Reusable plastic alternatives are probably not the best solution but are far superior to their single-use siblings. Remember Krazy Straws? Why not keep a couple at the office?

2. Acrylic

A step up, acrylic straws are the sort of straws that you find in the reusable cups sold at your local coffeehouse or donut shop. The acrylic is durable but can show some signs of wear from the dishwasher.

3. Glass

Elegant and sustainable, glass straws can up your fancy factor.

4. Metal

Like glass, aluminum or stainless steel straws can conduct temperature — but for ease and durability, metal is hard to beat. Plus, imagine drinking with a chilled, metal straw the way you would use a frosty mug.

5. Bamboo

Everyone knows about the renewability of bamboo as a resource, so why not capitalize on its strength and versatility to make a sustainable bamboo straw?

6. Plant-Based/Compostable

If single use is important, choose a plant-based product that will easily compost. Try a flavored, edible straw made from a seaweed-based material are on the way.

7. Paper

Classic striped paper straws will add a touch a whimsy and vintage feel to your lemonade, but be warned, some can wilt. Aardvark was the official partner of Strawless in Seattle and is known for making stronger straws.

8. No Straw At All

This is our preferred approach. Is no straw a radical move or just, as Strawless Ocean claims, an effort to stop sucking?

Don’t Forget

Keep in mind that if you do choose a reusable straw, you must clean that straw because it is the perfect environment for all kinds of nasty things to grow. It’s not always an easy feat, but many of the companies that make the reusable straws also offer handy, skinny brushes for just that purpose.

Editor’s Note: This article was originally published on April 24, 2018, and updated in March 2024.

Embracing the circular economy is vitally important for all industries, especially in the context of food packaging. Using food packaging that helps create a circular economy can transform the food packaging industry into a more sustainable and efficient system.

Although there can be many challenges when implementing more sustainable packaging, there are now innovative materials that the food packaging industry is using to revolutionize sustainable practices and embrace the circular economy. While adopting new technology will always involve some investment, the key benefits of investing in a circular economy are the long-term economic benefit and the potential for real cost savings through the entire supply chain. Benefits include:

• Reduced resource consumption: Designing products that last longer and are recyclable leads to cost savings as materials and components can be reused instead of purchasing new ones.
• Reduced waste disposal cost: Circular economy practices minimize the amount of waste, which means savings on waste disposal costs and potentially additional revenue if recycled materials can be sold.
• Enhanced brand reputation: There is an increasing demand for sustainable products, so embracing the circular economy can enhance brand reputation and attract new environmentally conscious customers.

The current lack of recycling initiatives is a key barrier to adopting a circular economy. However, embracing this model can overcome this challenge and simultaneously create new, local career and entrepreneurial opportunities in recycling. This approach addresses the initial hurdle and leverages it as a stepping stone towards innovation and sustainable practices.

Another challenge has traditionally been a lack of consumer awareness of sustainable food packaging. However, this is changing rapidly, with many consumers aware of the environmental impact of packaging materials and the benefits of choosing more sustainable options. To fully embrace the circular economy, there will be much collaboration required among various stakeholders to introduce and implement effective, sustainable strategies such as the Extended Producer Responsibility (EPR) program.

A sustainable future is possible if we address the existing challenges, explore innovative materials, and implement a circular food packaging system.

Innovation Required

Truly achieving a sustainable future requires more than acknowledging current challenges; it demands a multifaceted approach that encompasses the exploration of innovative materials and the adoption of a circular food packaging system. This holistic strategy extends beyond the establishment of recycling infrastructure, which is crucial but insufficient.

For real transformation to take place, we must prioritize designing packaging materials that are inherently recyclable or compostable. This shift necessitates a reimagining of product life cycles, ensuring that materials can be easily returned to the earth or repurposed into new products without environmental degradation.

Developing incentive programs is critical for encouraging both businesses and consumers to participate actively in recycling efforts. These programs can vary from financial rewards for returning packaging to discounts for choosing sustainable options, fostering a culture of responsibility and environmental stewardship.

Lastly, the emphasis on local solutions is pivotal in minimizing transportation impacts, one of the often overlooked aspects of packaging sustainability. By localizing the production and recycling of food packaging, we can significantly reduce the carbon footprint associated with transportation, making the journey toward sustainability more achievable and impactful.

Together, these elements—designing for recyclability and compostability, incentive programs, and local solutions—form the backbone of a circular food packaging system that addresses the immediate challenges and paves the way for a truly sustainable future.

The Crucial Role of Circular Economy in Modern Food Packaging 

As with any industry, food packagers must balance economics, convenience, and sustainability. The circular economy offers solutions to these challenges.

In the food packaging industry, achieving a balance between economics, convenience, and sustainability is paramount. The circular economy framework presents viable solutions to these challenges, notably by reducing the ‘green premium’—the additional cost often associated with sustainable practices.

While skepticism remains regarding the expansion of recycling options due to observed pullbacks in brand support for collection programs, the potential for growth in this area cannot be dismissed outright. Increased recycling capabilities and innovations in packaging design could enhance the availability of sustainable options, decreasing the green premium over time.

Currently, single-use plastic food packaging significantly impacts the environment, with 84% of plastic waste sent to landfills in Australia. As with all sustainable alternatives, increasing consumer awareness is a crucial factor. Although shoppers understand that some materials have a negative environmental impact, educating them about the benefits of sustainable options can increase demand and encourage investment in developing more innovative sustainable packaging materials.

Addressing food waste is crucial for resource efficiency and sustainability. Food waste contributes to greenhouse gas emissions and represents a loss of resources and money. Innovative solutions, like intelligent packaging and surplus food apps, can reduce waste and create more efficient packaging and distribution systems.

Embracing a holistic approach to food packaging demands comprehensive consideration of the packaging’s entire life cycle—from material sourcing to disposal. Central to this strategy is the prioritization of renewable materials, which significantly reduces the ecological footprint of packaging. These materials, derived from sustainable sources, are designed to have minimal impact on the planet.

It is crucial to address food waste through innovative packaging solutions. Packaging that extends the shelf life of food or allows for easier portion control can significantly reduce the amount of food discarded. This not only conserves resources but also diminishes the environmental damage associated with food production and disposal.

The journey towards sustainability is further advanced by amplifying the roles of reuse and recycling within the industry. A shift towards packaging designed for multiple uses, or easily recycled, plays a crucial role in reducing landfill waste. By developing and implementing effective collection and processing systems, we can ensure that more packaging materials are reclaimed and repurposed.

Implementing these steps requires a collaborative effort across the entire supply chain—from material producers to consumers. By integrating renewable materials, minimizing food waste, and enhancing reuse and recycling efforts, the food packaging industry can significantly contribute to more sustainable and efficient resource use, effectively closing the loop in the packaging lifecycle.

Circular Design Principles: Reshaping the Landscape of Food Packaging 

Circular design principles are changing how we approach food packaging, including integrating various kinds of sustainable food packaging options. These innovative solutions range from using renewable materials to compostable and recyclable packaging options, reflecting a commitment to environmental stewardship. Embracing circular design can promote sustainable materials while minimizing waste and offering economic benefits.

The design process behind sustainable packaging is crucial as true re-usability is key for any effective circular design system. Whether a product that can be continuously reused or something made from material like recycled polyethylene (rPET), which can be continuously recycled without losing quality, Food packaging should always encourage reuse wherever possible. By adopting modern recyclable and reusable materials, the carbon footprint of the food packaging industry can be massively reduced, thereby promoting a more sustainable future.

Using sustainable materials and innovation in the production process is a large contributor to creating a circular economy. Embracing circular design is all about closing the loop through recycling and composting. This is essential for modern businesses and consumers to protect the environment and its resources.

Sustainable Packaging: How to Make the Right Choices

Currently, the best way for consumers to identify the sustainability of food packaging is through correct labeling. Manufacturers investing in research and development to produce sustainable packaging will label the packaging to reflect this as a selling point.

Identifying sustainable food packaging relies on understanding credible labels. Trustworthy certifications include the Forest Stewardship Council (FSC) for paper and the Biodegradable Products Institute (BPI) for compostable products. The recyclability of plastics can be determined by the resin identification code (RIC), though local recycling capabilities must also be considered. Consumers should be cautious of vague terms like “recyclable,” which lack standardization. Instead, focus on specific labels that indicate third-party verification, such as products certified by the Cradle to Cradle Products Innovation Institute. Educating oneself on these labels can lead to more informed and sustainable choices.

Packaging certifications (such as BPI, FSC, and ISCC) and standard benchmarks can be good indicators of the environmental impact of certain food packaging. They can also be used to track the life cycle (known as start-of-life and end-of-life). These factors are used to analyze the total sustainability of a product and depend on the renewable nature of the materials, energy consumption used in production, carbon emissions, and recyclability or composability at its end-of-life.

Innovations Shaping Tomorrow: The Role of Technology in Circular Packaging

The drive toward sustainability in the packaging industry hinges on concrete innovations and the active participation of key players—namely, Consumer Packaged Goods (CPG) companies, who stand as the primary innovators. These entities are pivotal in integrating new material technologies, enhancing recycling processes, and employing smart packaging solutions that push the industry toward a circular economy.

Sustainable materials are just the starting point. CPG companies must invest in bioplastics and other recyclable materials and ensure these alternatives are compatible with advanced recycling technologies. This involves a dual commitment to developing durable, recyclable, or compostable materials, reducing the reliance on virgin resources.

Smart packaging with QR codes and RFID tags offers more than just tracking capabilities. It’s about establishing a robust infrastructure that utilizes these technologies to manage the lifecycle of packaging. Innovators must work towards systems that leverage data from these tags to streamline recycling processes, reduce waste, and even guide consumer behavior towards sustainability.

In the realm of supply chain optimization, the implementation of AI and data analytics by CPG companies is crucial for minimizing environmental impact. This goes beyond reducing costs—it’s about enhancing efficiency at every stage, from raw material sourcing to product distribution, ensuring minimal waste and energy use.

Consumer engagement is another critical area. Innovators should not only focus on technological and material advancements but also on initiatives that encourage responsible consumer behavior. This includes clear labeling, education on recycling practices, and incentives for choosing sustainable options.

The key for readers looking to support sustainability is to identify and back brands that transparently demonstrate their commitment to these innovations. Look for products with clear sustainability certifications, participate in recycling programs, and favor companies that invest in smart packaging and supply chain improvements.

About The Author

Felicity Kelly is the Head of Sustainability at Bunzl Australia & New Zealand. She assists organizations in enhancing their sustainability performance and reputation, as well as managing their entire value chain through stakeholder engagement, communication, risk management, problem-solving, strategy development, and execution. Felicity holds a Master’s degree in Corporate Environmental and Sustainability Management from Monash University. She has extensive experience working across various sectors, primarily in Fast-Moving Consumer Goods (FMCG) and logistics.

The double blind randomised controlled trial found that consuming food containing sweeteners produced a similar reduction in appetite sensations and appetite-related hormone responses as sugary foods — and provides some benefits such as lowering blood sugar, which may be particularly important in people at risk of developing type 2 diabetes.

The use of sweeteners in place of sugar in foods can be controversial due to conflicting reports about their potential to increase appetite. Previous studies have been carried out but did not provide robust evidence.

However, the researchers say their study, which meets the gold standard level of proof in scientific investigation, provides very strong evidence that sweeteners and sweetness enhancers do not negatively impact appetite and are beneficial for reducing sugar intake.

The trial was led by the University of Leeds in collaboration with the The Rhône-Alpes Research Center for Human Nutrition. It is the latest study to be published by the SWEET consortium of 29 European research, consumer and industry partners which is working to develop and review evidence on long term benefits and potential risks involved in switching over to sweeteners and sweetness enhancers in the context of public health and safety, obesity, and sustainability. It was funded by Horizon Europe.

Lead author Catherine Gibbons, Associate Professor in the University of Leeds’ School of Psychology, said: “Reducing sugar consumption has become a key public health target in the fight to reduce the rising burden of obesity-related metabolic diseases such as type 2 diabetes.

“Simply restricting sugar from foods without substitution may negatively impact its taste or increase sweet cravings, resulting in difficulties sticking to a low-sugar diet. Replacing sugars with sweeteners and sweetness enhancers in food products is one of the most widely used dietary and food manufacturing strategies to reduce sugar intake and improve the nutritional profile of commercial foods and beverages.”

Principal investigator Graham Finlayson, Professor of Psychobiology in the University of Leeds’ School of Psychology, said: “The use of sweeteners and sweetness enhancers has received a lot of negative attention, including high profile publications linking their consumption with impaired glycaemic response, toxicological damage to DNA and increased risk of heart attack and stroke. These reports contribute to the current befuddlement concerning the safety of sweeteners and sweetness enhancers among the general public and especially people at risk of metabolic diseases.

“Our study provides crucial evidence supporting the day-to-day use of sweeteners and sweetness enhancers for body weight and blood sugar control.”

The study, which is the first of its kind, looked at the effects of consuming biscuits containing either sugar or two types of food sweetener: natural sugar substitute Stevia, or artificial sweetener Neotame on 53 adult men and women with overweight or obesity.

Until now, virtually all studies of the effects of sweeteners and sweetness enhancers on appetite and glycaemia have been conducted using beverages as the vehicle. Few studies include volunteers with overweight or obesity and few have included volunteers of both sexes.

Most studies have only compared a single sweetener, mostly aspartame, with a control, and very few studies have examined the effect of repeated daily intake of a known sweetener or sweetness enhancer in the normal diet.

The new trial took place at the University of Leeds and the Rhône-Alpes Research Center for Human Nutrition (CRNH-RA), France between 2021 and 2022. Participants were all aged 18 to 60, with overweight or obesity.

The trial consisted of three two-week consumption periods, where participants consumed biscuits with either fruit filling containing sugar; natural sugar substitute Stevia, or artificial sweetener Neotame, each separated by a break of 14-21 days. Day 1 and day 14 of the consumption periods took place in the lab.

Participants were instructed to arrive in the lab after an overnight fast, a blood sample was taken to establish baseline levels of glucose, insulin and appetite-related hormones. They were also asked to rate their appetite and food preferences.

After consuming the biscuits, they were asked to rate how full they felt over several hours. Glucose and insulin levels were measured, as were ghrelin, glucagon-like peptide 1 and pancreatic polypeptide — hormones associated with the consumption of food.

The results from the two sweetener types showed no differences in appetite or endocrine responses compared to sugar, but insulin levels measured over two hours after eating were reduced, as were blood sugar levels.

SWEET project joint co-ordinator Professor Anne Raben, from the University of Copenhagen, Denmark, said: “The findings show that sweeteners are a helpful tool to reduce intake of added sugar without leading to a compensatory increase in appetite or energy intake, thereby supporting the usefulness of sweeteners for appetite, energy and weight management.”

The experts addressed setting standards for three key indoor pollutants — carbon dioxide (CO₂), carbon monoxide (CO), PM2.5 which are particles so small they can lodge deep in the lungs and enter the bloodstream — and ventilation rate.

Distinguished Professor Morawska, from the QUT School of Earth and Atmospheric Sciences, internationally known, among others, for leading the appeal to the WHO to recognise the airborne transmission spread of the Covid-19 virus early in the pandemic, has continued to raise the importance of adequate indoor air quality for public spaces.

“Most countries do not have any legislated indoor air quality (IAQ) performance standards for public spaces that address concentration levels of IA pollutants,” Professor Morawska said.

“To have practical value, IAQ standards must be implementable by designing new buildings that are built, operated and maintained to standard or retrofitted to meet the standards.

“While there is a cost in the short term, the social and economic benefits to public health, wellbeing and productivity will likely far outweigh the investment in cost in achieving clean indoor air.”

Professor Morawska said CO₂ sensors were readily available, inexpensive and robust and should be used as a proxy to measure pathogens and CO₂ during human occupancy in a public space.

“CO₂ can serve as a proxy for occupant-emitted contaminants and pathogens and to effectively assess ventilation quality,” she said.

“We propose a CO₂ concentration level of 800ppm with the proviso that outdoor concentration is used as a baseline and recognition of the fact that outdoor concentrations are increasing due to emissions to the atmosphere that outweigh removal.

“Another key indicator of air quality we addressed is the amount of PM2.5 and we propose the WHO air quality guidelines as a basis for indoor air quality standards but with a 1-hour averaging time, as the 24 hours of the WHO AQG is much longer than people usually spend in public places.”

Professor Morawska said mechanical ventilation systems should remove and dilute human-emitted and other indoor-generated pollutants at a higher rate than their production so that they would not accumulate in indoor air.

“The technologies for measuring ventilation already exist in most modern mechanically ventilated buildings but monitoring ventilation rates in terms of clean air delivered to the space requires us to consider the number of people and their activities in the space to ensure adequate IAQ.

“A practical ventilation standard could be air from outside (assumed to be clean), or clean recirculated air to the entire occupied zone and with airflow not directed from one person to another.

“Additional measures in support of ventilation, such as air cleaning and disinfection, could greatly reduce the need to increase the outdoor air supply, which carries a heavy energy demand.

“Filtering recirculated air is an effective way to reduce concentration of, and thus our exposure to, airborne particulate matter, allergens and pathogens.”

Now, researchers from Kyushu University have revealed that this ocean-atmosphere coupling enhances teleconnection patterns — when climate conditions change across vast regions of the globe — in the Northern Hemisphere. In their recent study, the team modelled the effect of ocean coupling on atmospheric circulation patterns, finding that extratropical ocean-atmosphere coupling causes more meandering jet streams, which are linked to extreme weather events.

Ocean-atmosphere coupling is most powerful in the tropics, where the coupling is responsible for the well-known “El Niño-Southern Oscillation” in the equatorial Pacific Ocean. The El Niño-Southern Oscillation, in turn, remotely leads to a meandering jet stream in the mid-latitudes through the formation of large-scale atmospheric circulation patterns, i.e., teleconnection patterns.

Outside the tropics, in the mid-latitudes, the impact of ocean-atmosphere coupling on teleconnection patterns is less understood. Nevertheless, its significance in the cause of extreme weather events cannot be ignored, especially in the eye of the climate crisis.

In a study published in the journal Communications Earth & Environment, a team of researchers led by Assistant Professor Masato Mori from Kyushu University’s Research Institute for Applied Mechanics, in collaboration with the University of Tokyo, Toyama University, and the Japan Agency for Marine-Earth Science and Technology, shed new light on the phenomenon.

“Because extreme weather events are more likely to occur when fluctuations in the jet streams are large — as in when the magnitude of the teleconnection pattern is large — it is important to understand the mechanisms that form and maintain said teleconnection pattern,” explains Mori.

To investigate the role of the extratropical ocean-atmosphere coupling, the researchers conducted two simulations: a coupled run, which considered the interaction between the extratropical ocean and the atmosphere, and an uncoupled run, which neglected the interaction between the two components. The simulations examined the impact of ocean-atmosphere coupling on teleconnection patterns during the Northern Hemisphere’s wintertime: December to February. The effect of the coupling on atmospheric circulation patterns were evaluated through atmospheric variables, such as air pressure and temperature.

In their simulations, the researchers observed significant changes in the atmospheric variables, especially in the North Pacific, subpolar North Atlantic, and northern Eurasia around the Barents-Kara Sea regions off the coast of Siberia. These changes indicated shifts in teleconnection patterns compared to simulations without such an interaction.

“Extratropical coupling selectively enhances the variance of three principal modes of variability, explaining 13%, 11%, and 10% of the total variance of Pacific/North American, North Atlantic Oscillation, and Warm-Arctic Cold-Eurasian patterns, respectively,” says Mori.

In the coupled run, heat exchange between the ocean and the atmosphere reduced the air-sea thermal difference. As a result, less heat is released from the oceans and into the atmosphere, leading to increased kinetic energy and a more meandering jet stream. Conversely, when the oceans are uncoupled, the sea surface temperature does not respond to atmospheric fluctuations. The larger temperature differences cause more heat to be released, resulting in a less meandering jet stream.

“The present study quantifies the coupling effect based on large ensemble simulations of a state-of-the-art fully coupled model. Moreover, it reveals how coupling selectively enhances multiple principal modes of variability, not only thermodynamically but also dynamically,” concludes Mori.

Notably, the researchers point out that the simulation could have underestimated the coupling effect owing to model bias and issues with simulation design. Nevertheless, new knowledge on the effects of ocean-atmosphere coupling in the Northern Hemisphere could contribute to improving climate projections in the face of the climate crisis through the improvement of climate models.

The research was conducted by the Reproduction, Nutrition, and Behavior in Insect Societies group at JGU under the supervision of Dr. Romain Libbrecht, an evolutionary biologist. The corresponding paper has recently been published in Functional Ecology. Dr. Romain Libbrecht currently works at the Centre National de la Recherche Scientifique (CNRS) in the Insect Biology Research Institute of the University of Tours.

Concept of insect societies as superorganisms consisting of specialized individuals

It is generally assumed that social insect colonies consist of queens that monopolize reproduction and sterile workers responsible for all non-reproduction-related tasks, such as the care of the brood, i.e., eggs and larvae. Libbrecht’s team now questioned this basic assumption. They focused on ant species where the queens found new colonies alone and without the help of workers. “Interestingly, these founding queens are not yet specialized in terms of their behavior at this stage of their lives,” Libbrecht pointed out. “They themselves assume all tasks in the nest, such as brood care, to ensure successful production of the first generation of workers.”

In their experiments, Libbrecht’s group studied the black garden ant Lasius niger that is native to Germany. They found the social environment to be a core factor in determining the behavioral specialization of founding queens. “The introduction of workers in the nests of founding queens suppressed the natural predisposition of the queens to look after their brood themselves. And, conversely, when we isolated queens specialized in egg-laying from their workers, they rapidly reverted to the brood care behavior observed in the case of founding queens, even after many years of specialization.”

Revision of the accepted view of the division of labor in insect societies

Libbrecht emphasized that the behavior observed during the study challenges the traditional view of social insect queens as being intrinsically specialized in egg production. Instead, the findings demonstrate that the presence of workers not only triggers the egg-laying specialization of queens but also actively maintains it in established colonies. The discovery of such social control of queen specialization may reshape our understanding of the functioning of insect societies and their division of labor.

Romain Libbrecht was head of the Reproduction, Nutrition, and Behavior in Insect Societies group at the Institute of Organismic and Molecular Evolution (IOME) at Johannes Gutenberg University Mainz from 2016 to 2022. Since 2023, he has been a researcher at the Insect Biology Research Institute at the CNRS of the University of Tours. He is particularly interested in examining how organisms adjust their reproduction, physiology, and behavior in response to environmental conditions.