There was a day when looking at the sky stunned human beings with wonder and fascination. The world seemed limitless, its brilliant bright blue waters, green spaces, and dense layer of leaves. The world symbolised harmony and beauty, full of natural wonders. From the outside space, the planet seen was nothing less than magical. But over the last decades, the complexion of our planet has altered radically, a reflection of the cost to the environment of human actions. A once-pure image now presents a filthier scene—a one of tension and decay.
NASA reveals Earth’s changing image from space
The image of a bright blue world glowing against the darkness of space touched hearts all over the world. It was a pioneering picture, showing an unknown perspective that united people and filled them with respect for the world. Several years later, in 1972, Apollo 17 astronauts captured the “Blue Marble” photo—a fully illuminated image of Earth, from the South Pole to all continents. This photo became one of the most widely shared photos in history. It wasn’t just beautiful—it also carried an unconscious message: a request to be kind to and take care of our world. NASA’s EPIC camera today photographs the Earth much more troubled. While the heavens still shine, they do not emit the same fierce blue that used to be the characteristic of our world. Melting oceans, felled trees, and blanket pollution have altered the hue of the world from above. The destruction that has already occurred to the planet can now be viewed from above, a harsh reminder of what has been achieved by decades of human neglect. Clean ecosystems are now scarred by global warming, and Earth’s once energetic vibrancy wanes.
Consequences of ignoring environmental warnings
Since the 1970s, environmentalists have warned of the dangers of carbon emissions and the increasingly likely threat of global warming. These early warnings were characterised by consistent, systematic voices calling for action to avert the climate crisis that confronts us today. But despite the seemingly clear evidence, the world failed to act on time. Through the decades, these warnings became conclusive evidence. Glaciers melted, islands disappeared, and animals were pushed to the point of extinction, but the world failed to take action swiftly enough to prevent it.
Deforestation and the Amazon’s struggle for survival
The oceans that once teemed with life are also facing extreme alteration. Ocean acidification is among the direst of the dilemmas, going up 30% over recent decades. That has caused sweeping destruction of coral reefs, reducing what we’reere thriving underwater communities into lifeless deserts. Also, plastic contamination has been raging epidemic-style, as millions of tons of plastic rubbish now lie strewn around our oceans. What was once a cradle for life is now a symbol of ecological despair. The oceans, which are so crucial to regulating the climate of the Earth and preserving marine biodiversity, now face attack, also a casualty of human endeavor. The Deforestation crisis, once one of the world’s most magnificent ecosystems, is disappearing at an alarming rate. Now referred to as the “lungs of the world,” the Amazon loses tens of millions of forest acres annually to deforestation. With gigantic waves of forest fires in places like Australia and California, where gigantic forests have been reduced to ash. The trees once removed carbon dioxide and maintained our atmosphere, but now they are taken from us, along with precious clean air. The destruction of such forests not only threatens biodiversity but also fuels the climate crisis since trees, when felled, result in increased CO2 levels in the atmosphere. A sign of accelerated climate change between the start of the 21st century and 2015, large areas of natural forest have been cleared and turned into roads and plantations. This conversion of land has led to the increase in temperature across the world. The last decade has seen a number of heat records broken, with the temperature increasing each year. The winters are shorter and the summers longer and hotter. This is very frequent in the Arctic region, where ice melts at a record pace. Thawing ice in the Arctic is creating new sea routes, but the cost is highest to the environment—ecosystems are lost, and the face of the world is being altered forever.
Challenge of climate action: Can we save our planet in time
The effects of climate change are emerging in sharper and more intense forms. Urban settlements that were previously considered to be safe from natural hazards are becoming more vulnerable to flooding due to sea-level rise. More frequent and intense heatwaves are impacting human habitation and ecosystems. Freshwater too is increasingly in short supply, with agriculture yields and drinking water sources impacted by droughts. These aren’t local changes—part of a global pattern of disruption that threatens the stability of entire ecosystems and regions. Renewable sources of energy, such as wind and solar power, are on the rise. More and more countries are taking global warming seriously these days, and international treaties to reduce carbon emissions are more and more popular. Businesses themselves are also under more and more pressure to reduce their footprint, with more and more choosing greener methods of conducting business. Action at a personal level is also on the rise, with more and more adopting sustainable living, reducing waste, and calling for tighter environmental controls. Also Read | Who was Dr. K. Kasturirangan? Former ISRO chief and the visionary behind the NEP—his contributions, awards, and more
Snipers in helicopters have shot more than 700 koalas in the Budj Bim National Park in western Victoria in recent weeks. It’s believed to be the first time koalas have been culled in this way.
The cull became public on Good Friday after local wildlife carers were reportedly tipped off.
A fire burned about 20% of the park in mid-March. The government said the cull was urgent because koalas had been left starving or burned.
Wildlife groups have expressed serious concern about how individual koalas had been chosen for culling, because the animals are assessed from a distance. It’s not clear how shooting from a helicopter complies with the state government’s own animal welfare and response plans for wildlife in disasters.
The Victorian government must explain why it is undertaking aerial culling and why it did so without announcing it publicly. The incident points to ongoing failures in managing these iconic marsupials, which are already threatened in other states.
Why did this happen?
Koalas live in eucalypt forests in Australia’s eastern and southern states. The species faces a double threat from habitat destruction and bushfire risk. They are considered endangered in New South Wales, Queensland and the Australian Capital Territory.
In Victoria, koala population levels are currently secure. But they are densely concentrated, often in fragments of bush known as “habitat islands” in the state’s southwest. Budj Bim National Park is one of these islands.
Over time, this concentration becomes a problem. When the koalas are too abundant, they can strip leaves from their favourite gums, killing the trees. The koalas must then move or risk starvation.
If fire or drought make these habitat islands impossible to live in, koalas in dense concentrations often have nowhere to go.
In Budj Bim, Victoria’s Department of Energy, Environment and Climate Action and Parks Victoria have tackled koala overpopulation alongside Traditional Owners by moving koalas to new locations or sterilising them.
But Budj Bim is also surrounded by commercial blue gum plantations. Koalas spread out through the plantations to graze on the leaves. Their populations grow. But when the plantations are logged, some koalas have to return to the national park, where food may be in short supply.
Animal welfare groups say logging is one reason Budj Bim had so many koalas.
It’s hard to say definitively whether this is the case, because the state environment department hasn’t shared much information. But researchers have found habitat islands lead to overabundance by preventing the natural dispersal of individuals.
So why was the culling done? Department officials have described the program as “primarily” motivated by animal welfare. After the bushfire last month, koalas have been left starving or injured.
Why shooters in helicopters? Here, the justification given is that the national park is difficult to access due to rocky terrain and fire damage, ruling out other methods.
Euthanising wildlife
Under Victoria’s plan for animal welfare during disasters, the environment department is responsible for examining and, where necessary, euthanising wildlife during an emergency.
For human intervention to be justified, euthanasia must be necessary on welfare grounds. Victoria’s response plan for fire-affected wildlife says culling is permitted when an animal’s health is “significantly” compromised, invasive treatment is required, or survival is unlikely.
For koalas, this could mean loss of digits or hands, burns to more than 15% of the body, pneumonia from smoke inhalation, or blindness or injuries requiring surgery. Euthanised females must also be promptly examined for young in their pouches.
The problem is that while aerial shooting can be accurate in some cases for larger animals, the method has questionable efficacy for smaller animals – especially in denser habitats.
It’s likely a number of koalas were seriously injured but not killed. But the shooters employed by the department were not able to thoroughly verify injuries or whether there were joeys in pouches, because they were in the air and reportedly 30 or more metres away from their targets.
While the department cited concerns about food resources as a reason for the cull, the state’s wildlife fire plan lays out another option: delivery of supplementary feed. Delivering fresh gum leaves could potentially have prevented starvation while the forest regenerates.
Lessons for the government
The state government should take steps to avoid tragic incidents like this from happening again.
Preserving remaining habitat across the state is a vital step, as is reconnecting isolated areas with habitat corridors. This would not only reduce the concentration of koalas in small pockets but increase viable refuges and give koalas safe paths to new food sources after a fire.
Future policies should be developed in consultation with Traditional Owners, who have detailed knowledge of species distributions and landscapes.
We need better ways to help wildlife in disasters. One step would be bringing wildlife rescue organisations into emergency management more broadly, as emphasised in the 2009 Victorian Bushfires Royal Commission and the more recent Royal Commission into National Natural Disaster Arrangements.
This latter report pointed to South Australia’s specialised emergency animal rescue and relief organisation – SAVEM – as an effective model. Under SA’s emergency management plan, the organisation is able to rapidly access burned areas after the fire has passed through.
Victoria’s dense communities of koalas would be well served by a similar organisation able to work alongside existing skilled firefighting services.
The goal would be to make it possible for rescuers to get to injured wildlife earlier and avoid any more mass aerial culls.
Liz Hicks is Lecturer in Law, University of Melbourne. Ashleigh Best is Barrister, Victorian Bar and Honorary Fellow, Melbourne Law School, University of Melbourne. This article is republished from The Conversation.
Investing in a budget water purifier offers numerous benefits, primarily by significantly improving the quality of your drinking water. Even seemingly clean tap water can harbour harmful contaminants like bacteria, viruses, heavy metals, and chlorine, which a purifier effectively reduces, leading to better health by preventing waterborne illnesses and long-term health issues.
Top Budget Water Purifiers of 2025: High Filtration Power for Every Water Type – Pure Water, Smart Savings.
Beyond health, a purifier enhances the taste and odour of water by removing treatment chemicals, making it more appealing to drink. While there’s an initial cost, it proves cost-effective in the long run compared to consistently purchasing bottled water, offering greater convenience.
Looking to make the switch? Check out the best budget water purifiers in 2025 here to get access to clean water throughout the day.
Clean drinking water isn’t just about purity, it’s about peace of mind, fewer health worries, and better-tasting meals. This best budget water purifier in 2025 from AQUA D PURE goes beyond filtration. The 10-stage system means fewer doctor visits for your kids, no foul odours in your cooking water, and confidence every time you fill a glass. With copper infusion, you’re not just removing impurities, you’re adding daily wellness with every sip, without stretching your monthly budget.
What are buyers saying on Amazon?
Buyers praise the purifier’s look, easy installation, and water taste, but report frequent malfunctions, UV filter issues, and leakage problems.
Why choose this product?
It gives you multi-stage safety, copper wellness, and consistent performance—all without paying premium prices.
Access to safe drinking water should not be a luxury, and the Aquatec Plus purifier ensures it remains a necessity for every household. Specially engineered for Indian homes with high Total Dissolved Solids (TDS), this purifier efficiently treats water with TDS levels of up to 2500 ppm. It features a comprehensive purification process, including RO, UV, UF, and a taste-enhancing filter, delivering water that is not only safe but also palatable. With no unpleasant aftertaste and reliable filtration, it offers a cost-effective solution for clean and healthy hydration.
What are buyers saying on Amazon?
Buyers find the purifier effective, easy to install, and stylish, but opinions vary on its 8-litre storage capacity.
Why choose this product?
It gives you powerful purification, flexible TDS control, and good capacity, without costing a fortune or needing constant attention.
Looking for a feature-rich yet budget-friendly water purifier in 2025? The AQUA LIBRA WITH DEVICE RO+UV+UF+Copper+TDS Adjuster is a solid pick for your home. It doesn’t just purify—it enhances. With copper infusion and TDS control, it ensures clean, mineral-rich water that tastes good and supports immunity. Perfect for borewell, tap, or municipal water, it uses multiple purification stages to eliminate contaminants like arsenic, rust, and bacteria. Plus, its sleek black body adds a touch of style to your kitchen.
What are buyers saying on Amazon?
Buyers like the purifier’s performance, price, and design, but report mixed service experiences and occasional issues with missing filters.
Why choose this product?
At just ₹5,199, it’s an affordable choice for families wanting safe, mineral-balanced drinking water with trusted ISI certification.
If you’re looking for the best budget water purifier that tackles daily water concerns without fuss, this one delivers where it matters. Its triple-layered purification means your family drinks water free from dust, germs, and microplastics. The in-tank UV keeps water fresh even during long power cuts. You don’t need to double-check the water source, this purifier adjusts to all. It’s practical, reliable, and fits into your routine like it’s always been there.
What are buyers saying on Amazon?
Buyers report RO system malfunctions and poor installation service, including unexpected cancellations and unresolved functionality issues after setup.
Why choose this product?
You should choose this product because it gives consistent purification across water sources, making it a smart everyday investment.
This best budget water purifier offers more than basic purification. It’s built for households that care about both safety and nutrition. Every drop is filtered through RO, then treated with UV to remove bacteria. The copper infusion adds essential minerals, while the TDS adjuster ensures the water tastes just right. It’s not just about removing impurities; it’s about delivering water that supports everyday immunity and wellness without making you spend a fortune.
What are buyers saying on Amazon?
Buyers find the purifier easy to install, stylish, and great for municipal water, offering good taste, performance, and value for money.
Why choose this product?
You should choose this product because it provides safe, mineral-rich water with long-term health benefits at an affordable price.
The Pureit Marina Prime is a reliable, feature-packed purifier designed to suit all water sources, be it borewell, tanker, or tap. It comes with 6-stage purification and a Mineral Enhancer Cartridge that adds essential minerals like calcium and magnesium for healthier, tastier water. Its Smartsense technology alerts you before filter expiry and stops dispensing unsafe water. With up to 45% water savings, this purifier is ideal for eco-conscious families.
What are buyers saying on Amazon?
Buyers appreciate the purifier’s quality, professional installation, appealing design, great taste, efficient performance, low water wastage, and overall value for money.
Why choose this product?
Choose it for peace of mind with Smartsense tech, mineral-rich hydration, and savings on water, perfect for modern, health-focused households.
The Kinsco Aqua Punch Pro Max is one of the best budget water purifiers in 2025 for homes, offering a combination of advanced filtration and added health benefits. With multiple purification stages like RO, UV, UF, and TDS adjuster, it ensures clean, safe water by removing large particles, bacteria, viruses, and dissolved impurities. The copper and alkaline elements help maintain a healthy pH level and promote immunity, while the UV lamp kills bacteria and viruses, making it an excellent choice for families looking for both safety and affordability.
What are buyers saying on Amazon?
Buyers praise the purifier’s quality, design, taste, and silent operation, but report mixed functionality and installation support experiences.
Why choose this product?
You should choose this product because it delivers purified, mineral-rich water at an affordable price with advanced filtration technology.
The Pureit Marina Plus is a reliable choice for families seeking safe and clean drinking water without compromise. With 6-stage purification, it ensures effective removal of impurities from all types of water like borewell, tanker, or municipal. Its UV sterilisation kills up to 99.9% of bacteria and viruses, while the mineral enhancer cartridge adds essential minerals like calcium and magnesium. With a 7-litre storage capacity, your family can enjoy continuous access to purified water without any hassle.
What are buyers saying on Amazon?
Buyers appreciate the purifier’s quality, sleek design, and effective impurity removal, but report mixed functionality and occasional performance issues.
Why choose this product?
You should choose this product because it offers powerful purification with essential minerals, ensuring safe water for your family every day.
The Aqua Libra RO+UV+UF+TDS Control Water Purifier provides a reliable solution for clean, safe drinking water. It uses a multi-stage purification process to eliminate dissolved impurities like arsenic, rust, and pesticides, while UV sterilisation ensures 99.9% bacteria and virus-free water. The TDS control system lets you adjust water hardness, ensuring essential minerals remain intact. With a 9-litre capacity, it serves medium to large households efficiently. Its wall-mountable design saves space, making it a practical addition to your kitchen.
What are buyers saying on Amazon?
Buyers find the purifier cost-effective, with great water quality and taste, but report mixed functionality, with some experiencing early malfunctions.
Why choose this product?
You should choose this product because it ensures purified water with essential minerals, making it perfect for safe, everyday use.
The Kinsco Aqua Moon 15 Litre Tank RO + UV + UF + TDS Adjuster Copper Water Purifier is designed for those seeking safe and clean drinking water. Equipped with RO, UV, UF filtration, and TDS adjuster, this purifier removes 99.9% of bacteria, viruses, and impurities. The added copper filter provides essential minerals, improving the quality of water. With a 15-litre capacity, it caters to medium-sized households. Its countertop installation and rechargeable feature make it a convenient and versatile choice for your kitchen.
What are buyers saying on Amazon?
Buyers praise the purifier’s quality, taste, and easy installation, but report mixed noise levels and occasional water leakage issues.
Why choose this product?
Choose this purifier for its combination of advanced filtration and copper infusion, ensuring you get purified, mineral-enriched water for you and your family.
Which type of water purifier is best for my home?
The right type depends on your water source. If you get hard water with high TDS (Total Dissolved Solids), an RO (Reverse Osmosis) purifier is ideal. For soft or municipal water with microbial contaminants, UV or UF purifiers work well. Many modern purifiers combine RO+UV+UF technologies to handle multiple impurities. It’s best to test your water quality first and then pick a purifier suited for that specific need. Choose a model with a TDS controller or mineraliser for better taste and essential minerals retention.
How often do I need to change the filters of my budget water purifier?
Filter change frequency depends on the purifier type and water quality. Typically, RO filters need replacement every 6 to 12 months, while UV lamps and sediment/carbon filters may last up to a year. If your water has more impurities, filters may clog sooner. Some purifiers come with filter change alerts for timely replacements. Regular maintenance is crucial to ensure purification performance and prevent harmful buildup. Always follow the brand’s guidelines and schedule a service check periodically to keep your purifier running efficiently.
Is a budget water purifier reliable and safe?
Yes, many budget water purifiers offer reliable performance, especially from reputable brands. They use essential filtration technologies like RO, UV, or UF and meet safety standards. While they might not have advanced features like app connectivity or digital displays, they do the core job, purifying water, effectively. It’s important to check for certifications like ISI or NSF and look at customer reviews. Also, ensure the purifier suits your water type. Budget models are a great entry point for households seeking clean drinking water without spending a fortune.
Factors to consider before buying the best budget water purifier in 2025
Water quality / TDS level: Test your water source for TDS and contaminants. If TDS is above 300 ppm, go for an RO purifier. For low TDS water, a UV or UF purifier is sufficient.
Purification technology: Choose the right technology—RO for dissolved salts, UV for killing germs, and UF for removing suspended particles. Many budget purifiers now offer a combination of these.
Storage capacity: Consider your daily water usage and pick a purifier with adequate storage (e.g., 7–10 litres) to avoid frequent refills, especially in power-cut-prone areas.
Filter replacement & maintenance cost: Budget purifiers may have low upfront costs, but filters need periodic replacement. Check annual maintenance costs and the availability of spare parts.
Brand reliability & service support: Opt for a trusted brand that offers good after-sales service, warranty, and easily available customer support, even for budget models.
Certifications & safety features: Look for purifiers with certifications like ISI, NSF, or WQA to ensure they meet safety standards. Also, check for features like filter change alerts or auto shut-off.
Top 3 features of the best budget water purifiers in 2025
Best budget water purifiers in 2025
Capacity
Purification method
Material
AQUA D PURE 4 in 1 Copper RO Water Purifier
12 Litres
RO, UV, UF, TDS Adjuster, 10 Stage Filtration
Copper, Plastic
Epic 15L RO+UV+UF+TDS Water Purifier for Home
15 Litres
RO, UV, UF, TDS
Plastic
Isi Mark Black Color Water Purifier With RO+Copper+UV Plus TDS Adjuster for Home (Model 2090)
10 Litres
RO, Copper, UV, TDS Adjuster
Copper, Plastic
Aquaguard Health Protect 3-in-1 RO+UV Water Purifier
7 Litres
RO, UV
Plastic, Stainless Steel
Isi Mark Black Color Water Purifier With RO+Copper+UV Plus TDS Adjuster for Home (Model 2090)
6 Litres
RO, Copper, UV, TDS Adjuster
Copper, Plastic
Pureit Marina Prime Mineral RO+MF Water Purifier
7 Litres
RO, MF (Mineral)
Plastic
Kinsco Aqua Punch Pro Max 21 L with ISI Mark RO+UV+UF+TDS Adjuster
21 Litres
RO, UV, UF, TDS Adjuster, ALK, Copper
Copper, Plastic
Pureit Marina Plus Mineral RO+UV Water Purifier
7 Litres
RO, UV, Mineral
Plastic
RO+UV+UF+TDS Control with Active Copper Premium Water Purifier
9 Litres
RO, UV, UF, TDS, Active Copper
Copper, Plastic
Kinsco Aqua Moon 15 Litre Tank RO + UV + UF + TDS Adjuster Copper Water Purifier Dispenser Machine
What is the best budget water purifier for high TDS water?
For high TDS water, choose an RO or RO+UV purifier. Look for models with TDS controllers or mineralisers for better taste and health.
Can I get a good water purifier under ₹10,000?
Absolutely. Several reputed brands offer efficient and certified water purifiers under ₹10,000 with essential features and decent storage.
How much does it cost to maintain a budget purifier?
Annual maintenance costs range from ₹2,000 – ₹4,000, depending on the model and water quality. RO purifiers generally cost more to maintain.
Do budget purifiers come with a warranty?
Yes, most budget purifiers include a 1-year warranty covering manufacturing defects. Some brands also offer extended warranty or AMC plans.
Is UV purification enough for city tap water?
If the TDS level is low and the water is municipally treated, a UV or UV+UF purifier is usually sufficient.
Disclaimer: At Hindustan Times, we help you stay up-to-date with the latest trends and products. Hindustan Times has an affiliate partnership, so we may get a part of the revenue when you make a purchase. We shall not be liable for any claim under applicable laws, including but not limited to the Consumer Protection Act, 2019, with respect to the products. The products listed in this article are in no particular order of priority.
In late 2019, a wave of billions of desert locusts flew into western India through Pakistan. Their journey had already spanned several thousand kilometers since they first erupted in the arid plains of East Africa.
Locusts are grasshoppers that, in the right conditions, multiply rapidly. They grow larger and change colour in response to their environment. In a process called gregarisation, they transition from solitary creatures to a swarm, congregating in large numbers and travelling together over several leagues at time.
Historically, these ‘outbreaks’ have led to widespread famine and economic devastation, earning them the name “locust plagues”.
The 2019-2022 outbreak was the worst to hit Kenya in 70 years and to hit Ethiopia, Somalia, and India in 25 years. More than 200,000 hectares of crops were destroyed.
At this time, researchers in German and North American universities saw an opportunity to study locust swarms and flew to Kenya, hoping to refine a long-standing theory about swarming behaviour.
Previous models of locust swarms have treated them like gases in motion. Specifically, they assumed individual locusts aligned with their neighbors like self-propelled particles — a model-object used in theoretical physics.
“Initially, we wanted to replicate what we thought we knew,” Iain Couzin, director of the Max Planck Institute of Animal Behavior and professor at the University of Konstanz, who has studied collective intelligence and locust behavior for over two decades, said. “But what we didn’t expect was to find that we could not replicate our previous findings, and that completely changed our understanding of how locusts form these massive swarms.”
In a recent paper, Couzin and his team proposed a revised model to make sense of swarms. According to this model, locusts don’t behave like gases. Instead, their movement is based on a cognitive decision-making process based on their perception of nearby motion.
The finding marks a major shift in how scientists understand locust behaviour and their ability to make swarm-related predictions. As climate change continues to alter locusts’ breeding patterns, this refined understanding may be the key to protecting crops, and livelihoods, before the next swarm arrives.
From field to holograms
Just before the spread of COVID-19 became a pandemic, some members of the research team (other than Couzin) conducted a study in Kenya’s Samburu and Isiolo counties. They examined large, ground-marching bands of young locusts using precise tracking methods, and noticed a pattern. The locusts weren’t explicitly aligning with their immediate neighbors, contrary to what the self-propelled particles model predicted.
To test their observations, they conducted sensory-deprivation experiments in which they altered the insects’ ability to see, smell or sense movement.
The results revealed that vision had a major influence in determining how locusts moved within a swarm. Locusts that couldn’t see clearly lost their sense of direction while those with intact vision moved with the swarm even without physical contact.
“Those data showed that olfaction wasn’t important, tactile cues weren’t important, but vision was really, really important,” Couzin said. “That justified the use of holographic virtual reality to study this phenomenon in more detail.”
The scientists placed locusts in a fully immersive virtual-reality environment and tested their response to different visual stimuli. In these experiments, the locusts interacted with computer-generated swarms that varied in density and movement order. Soon, their key finding emerged: coherence of motion rather than crowding controlled their alignment.
Even in sparsely populated swarms, the locusts moved together if their visual cues were strong.
The team realised locusts weren’t behaving like gas particles. Instead, their movement followed a decision-making process based on their perception of nearby motion.
To represent this, the researchers developed a new mathematical model based on a neural ring attractor network, a concept in neuroscience. Instead of treating locusts as mindless particles, the approach addressed them as decision-making entities that could integrate multiple visual inputs before choosing a direction.
The model suggested locusts may weigh different potential options and make effective decisions. “However, at the group level, there’s no planning at all,” Couzin added. “The group is an emergent phenomenon.”
An emergent phenomenon is a complex pattern arising from simple interactions, without central control. In locust swarms, collective movement emerges from each locust’s individual behavior, creating large, coordinated swarms without a leader. This is how flocks of birds and traffic jams work, too.
“This study established how swarms move and how coordinated motion arises,” Sercan Sayin, neurologist and molecular biologist at the University of Konstanz and one of the study’s authors, said. “The initial direction selection and how this is maintained — that’s the next question we would like to answer.”
‘Wrong way of thinking’
Understanding how locusts move has real-world consequences. Yet how these groups emerge or which exact factors determine the direction of their flight remains unclear.
Climate change has worsened the problem by increasing rainfall in desert regions, creating ideal breeding conditions. The 2019-2022 outbreak — one of the worst in decades — was fueled by unusually strong monsoons and cyclones in the Arabian Sea. Cyclones Mekunu and Luban had also struck the Arabian Peninsula in 2018. Unusual monsoons and delayed control worsened the crisis, creating a swarm.
“We thought we had a good understanding, and the old models were being used to try to make predictions, but that was the wrong way of thinking,” Couzin said. “Hopefully, now we’ve set the record straight and we can start building a team effort to make increasingly accurate predictions. One way to do that, of course, is to start tracking animals in the wild.”
“With the changing climate, the swarms are expected to become larger and more unpredictable, making management more difficult,” he added. “To really be able to make predictive models or understand this better, we need much more research. We also need to involve climate scientists and vegetation experts.”
Monika Mondal is a freelance science and environment journalist.
