In the 2008 film The Dark Knight, there is a scene in which a would-be criminal decides against committing a crime after he sees the Bat Signal in Gotham City’s dark sky. The man chooses to mind his behavior since Batman could see him. But that’s in the fantastical world of comic book movies. That type of thing can’t happen in real life… right? Well, psychologists in Milan, Italy put this to the test.

In a psychological experiment, researchers from the Università Cattolica del Sacro Cuore found the sudden appearance of Batman caused people to become more altruistic. This mass change of behavior among a group has led Francesco Pagnini, Professor of Clinical Psychology at Università Cattolica, and his team to coin this prosocial behavior the “Batman Effect.”

The experiment was fairly simple. Professor Pagnini had a woman who appeared to be pregnant get onto a train with 138 people, including an observer planted to gauge the reactions of the passengers—would any of them offer their seat to her?

The second part of the experiment had the same scenario, but included a man in a Batman costume getting onto the train from another entrance. The purpose of the experiment was to see if an unexpected event, such as the appearance of a superhero, shook up people’s routines and increased awareness of the present moment.

The results of the experiment were surprisingly like a comic book. Without “Batman,” only 37.66% of the passengers offered their seats to the pregnant woman. However, 67.21% of the passengers offered their seats when an unexpected Dark Knight appeared on their subway train. In other words, Batman’s presence caused roughly twice as many people to kindly offer their seats to the pregnant woman compared to a “normal” ride. Another interesting note was that 44% of the people who offered their seats when the Caped Crusader was on the train reported not having seen anyone in a Batman outfit, suggesting that unexpected events could promote prosocial behavior even in the absence of awareness.

“Our findings are similar to those of previous research linking present-moment awareness (mindfulness) to greater prosociality; this may create a context in which individuals become more attuned to social cues,” said Professor Pagnini in a statement. “This suggests a potential mechanism through which novelty and unpredictability promote prosocial behavior, strengthening theories linking attentional shifts to increased social responsiveness.”

Pagnini didn’t rule out that Batman and what he represents played a significant factor in the experiment’s results (aside from the unexpected nature of a superhero taking the subway with regular passengers).

“It is also possible that the superhero figure enhanced the relevance of cultural values, gender roles, and norms of chivalrous help, consistent with research on the ‘priming’ effect associated with superheroes,” added Pagnini. “The figure of Batman could therefore play a prosocial priming role.”

The result of this experiment has had some psychologists offer methods for people who want to be more altruistic or improve their daily lives. It may not be a picture of Batman, but having a photo of someone you admire or aspire to be like can help motivate you towards goals that reflect who they are or what they’ve accomplished. In terms of the subway experiment, that shows that making a slight change in your routine, such as taking a different route to work or a different place to have coffee, would force your brain off of auto-pilot to take in the differences of life around you.

The result of this experiment shows that a little bit of shake-up of your usual routine could increase your awareness of what and who around you could use your help. This could help you become more of a superhero in real life (costume optional).

  • How D.C.’s ‘humanure’ fertilizer creates lush gardens and big profits while improving the environment
    Photo credit: CanvaWhat you flush away could help your garden grow.

    The District of Columbia Water and Sewer Authority—now known as D.C. Water—has long provided water and sewer services to Washington, D.C. But for the past decade, the utility has also had an unexpected side hustle: turning human wastewater into fertilizer with flourishing results.

    At most wastewater treatment plants, flushed water is cleaned, while the remaining solid matter is hauled away for disposal. Over time, transporting and disposing of that waste can cost millions of dollars while increasing carbon emissions from the trucks carrying it. A decade ago, however, D.C. Water decided to invest in transforming the solid waste into “humanure” rather than throwing it away.

    Growin’ grass and makin’ gas

    At the end of the wastewater treatment process, the collected human waste solids are processed into biosolid fertilizer using technology developed by Norwegian company Cambi. The process doesn’t just produce high-quality fertilizer—it also generates biogas that can be put to good use.

    “So you get up to 40% more biogas,” Cambi CEO Eirik Fadnes said. “That biogas can be used to generate electricity to be used elsewhere in the wastewater-treatment plant or put on the grid and sold.”

    D.C. Water sells the biosolid fertilizer under the brand name Bloom, and it’s already proving to be a success. Bloom has been used throughout the Washington, D.C., area by customers including Catholic University, Mount Olivet Cemetery, and the Franciscan Monastery. It’s also used on numerous lawns, school grounds, community gardens, and golf courses.

    Success by the numbers

    The numbers underscore D.C. Water’s success. To date, nearly 400,000 tons of Bloom have been sold across Washington, D.C., Maryland, Pennsylvania, and Virginia, generating $13.6 million in revenue. D.C. Water originally estimated it would take 20 years for Bloom to pay off its investment. But thanks to strong demand from institutions, landscapers, and local garden centers, the utility is now on pace to recoup that investment in just 12 years.

    Bloom is also helping D.C. Water meet its environmental goals. By turning waste into a useful product instead of hauling it away for disposal, the utility has reduced its carbon footprint by roughly 50,000 metric tons of CO₂ emissions each year—the equivalent of taking more than 11,700 gas-powered cars off the road annually. The process also produces biogas, which can be converted into electricity to help offset the energy costs of wastewater treatment.

    Human waste works wonders

    None of this would matter if human biosolids weren’t effective at improving soil. “Humanure,” a term coined by Joseph Jenkins, refers to compost made from properly treated human waste. Because human feces can contain disease-causing pathogens, it must be handled carefully. After all, we call it “waste” for a reason.

    When human waste is composted correctly, naturally occurring microbes break down the organic material while generating enough heat to destroy harmful pathogens. Over time, the result is a nutrient-rich compost that can improve soil health. Some farmers even build specialized outdoor composting toilets to create humanure for use on their land.

    Should D.C. Water continue on this path of simultaneous profitability and environmental improvement, it’s likely other wastewater treatment plants will follow its lead.

  • A Spanish park has been free of wildfires for over a decade thanks to 18 donkeys
    Photo credit: CanvaDonkeys and other livestock could help prevent mass wildfires.

    According to NASA, wildfires have doubled worldwide due to climate change. Throughout the globe, governments and environmentalists have been trying to find ways to curb the fires. One particular national park in Spain has found a solution that has been keeping them fire-free for over a decade: donkeys.

    Since 2014, the Firefighting Donkey Battalion unit consisting of 18 donkeys has been preventing wildfires in Doñana National Park in Doñana, Spain. The mission these donkeys do is simple: eat the dry brush that usually sparks and fuels wildfires. The donkeys spend up to seven hours a day using their voracious appetites to graze and clear a 130 by 50 feet area of dried grass, scrub, and other vegetation.

    Why donkeys?

    While humans can do this type of clearing out of dry brush, using donkeys for this work is arguably more effective. While it is a slower process, it is consistent and thorough. Donkeys are able to quietly patrol in areas that are inaccessible to vehicles. In exchange for the feasting, the donkeys get about eight gallons of water and rest. No money or fuel needed.

    The donkeys’ bodies are also pretty much built for this kind of environmental work, too. Their stomachs are built to eat the same rough and dry grass repeatedly without issues. These daily grazings slowly but surely remove potential origin sources for fires. As a bonus, the donkeys are naturally disposing of the dried vegetation whereas humans would have to find a different way to dispose of it.

    Having donkeys or other livestock graze in such areas was once more common in agriculture prior to modern farming. Some argue that the machinization of farming and urbanization have reduced the number of grazing animals. This in turn allows more vegetation growth that become dry spots for more wildfires to occur.

    The method expands

    This method has been so successful that other areas of Spain have adopted it. In 2020, Tivissa launched the Burros Bomberos project with three donkeys to so much success they’ve expanded. They now have 40 donkeys grazing and clearing nearly 400 hectares of land.

    The Andrea Association in Allariz uses a team of donkeys to clear and maintain nearly 1,000 hectares of a biosphere reserve. Using GPS to monitor the donkeys’ activity, the group of grazers travel 19 kilometers per day to feed. Similar initiatives have since started in Basque Country, Catalonia, and Galicia, too.

    Other ways to combat wildfires

    In the United States, California has been using goats in a similar function. The group Fire Grazers Inc. has been contacted throughout California to bring hundreds of goats to eat dried vegetation. Much like donkeys, goats are built to eat rough and dry brush. This includes certain plants such as star thistle that are painful for human hands to grab.

    It’s important to note that donkeys or other animals that eat dry scrub are the primary solution to wildfires. The same folks behind these initiatives also advocate proper forest planning and land management. This includes reducing the amount of easily flammable species of plants and trees such as pine. It takes thought, care, work, and maybe a bunch of donkeys to make a difference.

  • Spanish zoo study suggests that giraffes can do basic math
    Photo credit: CanvaA study is showing giraffes could be using math.
    ,

    Spanish zoo study suggests that giraffes can do basic math

    These hoofed mammals can understand addition.

    The results of an experiment done in a Barcelona zoo suggest that giraffes are capable of doing basic mathematics.

    A group of researchers from the University of Leipzig, the Max Planck Institute for Evolutionary Anthropology, and the University of Barcelona published their study observing four giraffes at the Barcelona Zoo. The experiment involved the giraffes observing containers that had different amounts of carrot pieces inside.

    How did this experiment work?

    The researchers showed each giraffe the two yellow containers and the amount of carrots within each one. After a few seconds, they closed the containers, keeping the carrots out of sight. They then showed each giraffe a green container which had extra carrots inside. Researchers took the carrot pieces from the green container and placed them into one of the closed yellow containers. They then let each giraffe independently choose which of the two closed yellow containers they preferred, without them seeing the total number of carrot pieces within each box.

    The results found the giraffes would choose the container that had the most carrot pieces around 68% of the time. This suggests to the scientists that the giraffes were mentally adding the carrots up in each container before making their choice. After all, there have been past studies suggesting that other hoofed mammals, such as horses, had similar capability of basic quantity tracking.

    The researchers did the experiment again. Only this time they subtracted the amount of carrots in each container. The giraffes were mostly unsuccessful at finding the container with the most pieces. So while giraffes showed signs of knowing addition, they don’t quite process all forms of arithmetic.

    Math = Survival

    Scientists believe that this understanding of addition helped giraffes survive in the wild. They cite that acacia trees, a dietary staple for wild giraffes, can be spread far apart in Africa. Being able to figure out which area has the most trees and the most leaves can help them decide where to graze next.

    Giraffes also live in flexible groups that often change in size. One grouping can mix in with another group and then branch off or away. This means that the giraffes often have to keep track of those currently within their group and surroundings to survive.

    Can other animals do math?

    Giraffes are just the latest animal species known to have some form of mathematical skill. Chimpanzees displayed similar abilities to count as giraffes in a similar experiment that involved them picking the bowl with the most chocolate pieces rather than carrots. Chickens and black bears also showed aptitude in quantity tracking, too. 

    Scientists theorize that most of the animals that can do this basic math through evolutionary survival. After all, the animal that can deduce where more food is tends to live longer.

    One species that displays remarkable mathematical ability are Tunisian desert ants. An observation of their navigational skills of finding their way to food and back to their nest suggests they use the sun as a compass in combination with mentally keeping track of the number of steps they take in a three-dimensional space. In short, these desert ants possess basic geometric and trigonometry skills.

    While you wouldn’t want wild animals to calculate your taxes, it’s interesting to see how rudimentary math is a language that goes beyond species.

Explore More Science Stories

Environment

A Spanish park has been free of wildfires for over a decade thanks to 18 donkeys

Science

Spanish zoo study suggests that giraffes can do basic math

Environment

Beyond birds and mice, free‑ranging cats eat a surprising number of insects

Environment

The University of Cambridge found a way to reduce plastic waste and create clean hydrogen energy at the same time