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An Australian magpie. Image Credit: NAPARAZZI, Flickr

How magpies outwitted researchers in Australia

When Dominique Potvin and her team set out to test a new technology for tracking birds, they didn’t think they were entering into an interspecies game of one-upmanship. Instead, Potvin, an animal ecologist at the University of the Sunshine Coast in Australia, was hoping to both track the animals’ movements and solve a persistent issue in the study of birds. Approximately 70% are too small to be tracked using a traditional battery-powered GPS tracker, since the weight of the devices can harm them. The new, harness-based trackers Potvin and her team had developed weighed only one gram, with a strap that could detach if the birds approached a specialized magnetic station. That would allow the researchers to collect the trackers without having to recapture the birds.“We wanted to see if the new design would work as planned, and discover what kind of data we could gather,” Potvin wrote in a recent piece <a href="https://theconversation.com/altruism-in-birds-magpies-have-outwitted-scientists-by-helping-each-other-remove-tracking-devices-175246">for The Conversation</a>. “How far did magpies go? Did they have patterns or schedules throughout the day in terms of movement, and socialising? How did age, sex or dominance rank affect their activities?” Australian magpies also seemed to her a prime species for testing new tracking technology because of their larger size. The accepted size of a tracker in ornithology is about 3%-5% of an animal’s body weight. These new trackers weighed about 1%. “We were excited by the design,” she wrote.
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But the magpies had other ideas. During the month that Potvin and her team spent fitting five magpies with trackers and watching their behavior, “we directly observed four actively removing the trackers,” they <a href="https://www.birdlife.org.au/afo/index.php/afo">wrote in a study</a> published last month in the journal Australian Field Ornithology. At first, the birds pecked at their own trackers—but then something more interesting happened. An adult female approached one of the juveniles fitted with a tracker and pecked at the device until it came apart and fell off. At the same time, elsewhere, another adult magpie also had its device destroyed by a companion. Soon, all the other trackers had been removed.The team wasn’t too concerned when the magpies started pecking at the harnesses, “but the more time went on and the more they worked on the harness, the more worried we became,” Potvin said by email. “As soon as that first tracker came off, we just looked at each other in disbelief: we knew it was all over!”She and her team were astonished. What, they wondered, could this unlikely outcome mean?Potvin and her team saw the magpies’ tiny mutiny as something more than a stunt. Australian birds have a reputation for being collaborative. The continent is the world capital for cooperative breeding, where birds help raise chicks of the same species that aren’t their own—a behavior Australian magpies engage in. They’re also known for working together to defend their territories.Since the magpies already have experience cooperating to solve problems, the authors argued, they might apply the same strategy to a new challenge. They interpreted the magpies’ removing each other’s trackers as altruistic behavior, or actions that only benefit another individual. The first magpie that destroyed another’s harness wasn’t wearing one itself, Potvin said over email, meaning that “the work was not going to be reciprocated.” She did note, however, that it’s possible the behavior might strengthen social relationships, creating long-term benefit. “These kinds of rewards are definitely plausible, but we have no way of knowing whether they played a part in this activity,” she wrote.In looking for an explanation, Potvin and her team first thought of allopreening, a behavior where birds clean each other—sometimes removing parasites—to strengthen their bonds. But that is “a very straightforward behaviour, and does not involve any kind of determination, persistence or problem solving,” she wrote, “it’s not really ‘targeted’ with a specific goal in mind.”Instead, they thought the most likely explanation was that the magpies were exhibiting “rescue behavior,” a very rare phenomenon in which one helper animal works to free a peer in distress, with no benefit to itself. Although the tracker was not dangerous, wearing it “may have felt a bit like being ‘tangled’” for the magpies, Potvin wrote, prompting other birds to respond.
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<img alt="Australian magpie on fence" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/27810942789_a3f5de916e_o.width-990_IUB30Xb.jpg"/>
<figcaption>An Australian magpie sits on a school gate post. Image Credit: birdsaspoetry, Flickr
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The removal of the trackers represented a series of puzzles “requiring cooperation (the bird with the tracker had to stand pretty still for the other bird to work on them!), some altruism, and some cognitive problem solving,” she added. Such rescue behavior has been observed in Seychelles warblers, which sometimes get sticky seeds caught in their feathers, but until now researchers haven’t documented it in other birds. “It is possible that what we have observed is the first documented case of rescue behaviour in Australian Magpies,” the team concluded in its study.Gisela Kaplan, a professor of animal behavior and zoologist at the University of New England in Australia who has studied Australian magpies for decades, agrees that pilot studies like Potvin’s are valuable for testing new technology on a small scale. But she emphasizes that the group of five magpies was likely a family, making the observations tantamount to one single anecdote. “I’ve seen lots of individual behaviors in magpies that I couldn’t explain,” Kaplan says—for example, she has written <a href="https://theconversation.com/magpies-can-form-friendships-with-people-heres-how-83950">for The Conversation</a> about a magpie in her yard who appeared to be gardening with her, and another instance in which one flew into her home and pecked at her keyboard after watching her type—“but I wouldn’t have written a paper about it.”Lisa Horn, a comparative behavior researcher in Vienna, Austria, who studies altruistic behavior, agrees—especially since the team didn’t set out to test that kind of behavior. “Coming from a tradition of cognitive biology, we’re very careful with our experimental design, to try to rule out any other explanations and carefully control the conditions,” she says. But that kind of design is impossible when the outcome is an accident.Kaplan suggests there are other possible explanations for the magpies’ digital striptease that could be just as interesting, including “play behavior, competitive behavior, all sorts of things.” Kaplan’s research has shown that juvenile magpies play quite a lot, including among themselves and with objects. “The object play that I’ve observed is always competitive,” she says, adding that many of those play interactions include stealing a desired item.
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Another possibility, Horn suggests, is simple distress. “A lot of songbirds, and also Australian magpies, have very close social bonds with their partner,” she says. “If something happens to my mate, and it freaks my mate out, that also freaks me out.” That leads to what Horn calls “emotional contagion,” and the desire on all sides to resolve the distressing situation. This is a much simpler mechanism that is found in a wider array of animals than generosity, empathy, or altruism, she says. The danger in such circumstances is anthropomorphism, ascribing human experiences to animals because that’s how we might behave or feel. “Especially in cognitive biology and behavioral biology, we are very careful with using these terms,” she says.But while Potvin agrees that being thoughtful about anthropomorphism is important, she feels it can sometimes be “helpful, or even somewhat accurate” to consider the parallels between human and animal behavior. “The risk comes when we think we know what the birds are actually thinking,” she said over email. For example, they don’t know how the birds viewed the trackers, nor their problem solving strategy for removing them. “But we do know what they did, and that in and of itself is pretty impressive.”Both Horn and Kaplan agree that the idea that the magpies may exhibit rescue behavior is plausible. After all, the birds are remarkably cooperative in other ways. Plus, similarly empathetic “consoling” behavior has been observed a few times in ravens. And in Horn’s own research, she found that certain crows and magpies (though not the kind in Potvin’s study) were particularly likely to help others. Since both of the species <a href="https://elifesciences.org/articles/58139">in Horn’s research</a> were also cooperative breeders, she hypothesizes that having “such a family system—parents but also maybe aunts, uncles, someone else helping—seems to have led to a lot of this prosocial behavior in other areas.”But, Kaplan says, jumping right to rescue is a big deal because it implies empathy, or even “theory of mind,” the ability to imagine an experience different than one’s own—which all but the most intelligent animals lack. And even if it turns out that magpies do have theory of mind, that’s a separate thing from saying “I care,” Horn adds.Still, Potvin feels it’s not such an enormous leap, given that magpies’ cognitive abilities and complex social relationships are well established. Since the publication of her study, many readers have reached out to her to describe instances they’ve seen of similar behavior that appears altruistic or “rescue-like.” Could that suggest the behavior may be more common than previously thought? “I think that many people who watch and study birds have seen similar behaviours,” she wrote by email, “and thus the evidence is there for them.”Kaplan hopes that Potvin and her team (or someone else in the avian cognition community) will use these observations as a jumping off point, carefully designing an experiment to test their rescue behavior hypothesis —perhaps a study to see if Australian magpies would work together to get food or would help a peer weighed down with some burden or restriction similar to the trackers. The study makes a great starting point, she says: Accidental observations are “often how further experiments start.” She points to Alexander Fleming’s discovery of Penicillin on a moldy dish. “The important point was that he didn’t expect that result but was in the right place at the right time and had the training to pursue this in a scientific manner,” she says. Someone else might have spotted the mold and thrown the whole thing away. “But he didn’t. He thought it was a significant event.”
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During a recent study, a group of magpies removed their GPS trackers, astounding their observers. But were the birds actually trying to help each other?

Animal Care Supervisor Lisa Dijenno bottle-feeds a manatee named Tober. Image courtesy of ZooTampa

A day at a Florida manatee hospital

On December 7, 2021, NOVA Digital Editor Alissa Greenberg visited ZooTampa’s David A. Straz, Jr. Manatee Critical Care Center to see up close how rescued manatees are recovering and regaining strength amid an ecological crisis and widespread starvation.10:15 a.m. It’s feeding time at the manatee critical care center at ZooTampa, and the calves are ready and waiting. Even before the staff brings bottles of thick formula over to the pool where they are swimming, four sets of fuzzy nostrils break the surface, whiskers wiggling. “As you can see, they know it’s time,” says Animal Care Associate Kelcey Innes. The calves, which are all smaller than a duffel bag but may someday weigh close to 1,000 pounds, suck down the formula, then chew on the bottles’ rubber nipples playfully. 
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There will be more food soon enough—calves at the center are fed every four hours around the clock. But for now, Innes and coworker Sabrina Sauseda have a different task: watch for manatee farts, proof of digestive systems in working order. After a few minutes, Sauseda spots telltale bubbles. “Calliope had gas!” she announces.The center keeps up this intensive feeding schedule because if the calves were still nursing with their mothers, they would be gaining at least a pound a day. But these calves are orphans, part of an ongoing manatee crisis in Florida. Manatees are in trouble all over the state—particularly on its Atlantic (east) coast, they are starving. Last year was the <a href="https://www.tampabay.com/news/environment/2022/01/10/a-record-1101-florida-manatees-died-in-2021-when-will-it-end/">deadliest on record</a>, with more than 1,100 manatees dead, close to 15% of the state’s population. The reason is seagrass: The Florida coast is home to what were once two of the largest undersea meadows in North America, and the plant makes up much of the manatee diet. But <a href="https://news.mongabay.com/2021/09/manatee-deaths-in-florida-point-to-a-global-decline-in-seagrass-ecosystems/">Florida's seagrass</a> ecosystems are collapsing, due largely to fertilizer and development runoff. In the Indian River Lagoon, once one of the continent's most productive estuaries, seagrass has declined an estimated 95% in the last 10 years.As one of four manatee critical care centers in the country, ZooTampa is caring for 23 <a href="https://www.mmc.gov/priority-topics/species-of-concern/florida-manatee/">manatees</a> on this December morning, double its historic capacity. A mother manatee may feed her calf until she starves, so the facility has also taken on an unprecedented number of calves in the past year, left alone after their parents perished. As their state attempts to clean up its waterways, the staff at ZooTampa are working overtime to save the animals that mean so much to the soul of Florida.
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<img alt="A woman bottle feeding two manatee calves in a pool" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/Animal_Care_Professional_Sabrina_Sauseda_bottl.width-990_eTRwlCm.jpg"/>
<figcaption>Animal Care Professional Sabrina Sauseda bottle-feeds orphaned mantee calves at ZooTampa. Image courtesy of ZooTampa
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10:35 a.m. It’s also time for morning tube feeding. Two new residents have arrived within the last week, along with the early winter chill. Both were suffering from cold stress; one had a fresh boat propeller injury across his face. And they both need to eat while they convalesce.When a new manatee comes to the center after rescue by the Department of Fish and Wildlife, Animal Care Supervisor Jaime Vaccaro and her staff check its blood levels, respiration, and measurements. Then they set the new resident up in one of three medical pools that make up the hospital’s intensive care area. Each of these interconnected pools is equipped with its own heater, a vertical gate that can be lowered to cut off access, and a hydraulic floor that can be raised and lowered. This feature allows the staff to both customize the environment and raise the manatees out of the water for medical care.Last week’s adult arrival, Corduroy, is in too much distress to eat. After they use the hydraulics to lift him out of the pool, Vaccaro and Innes take some of Corduroy’s blood, then gingerly thread a length of plastic tubing down his throat. His tail flaps a little, but he calms and accepts the liquid quietly. Manatees’ complicated digestive systems are especially sensitive, so the staff tube-feed Corduroy multiple times a day to make sure he stays hydrated and maintains his weight until he’s ready to eat on his own—a process that could take months. Manatee digestion is “like the engine of a car,” Vaccaro says. “If they've been sitting for a while, they might not start back up right away.” Director of Conservation, Research, and Behavior Tiffany Burns connects the increasing number of manatee patients with Florida’s persistent water quality problems. “They look big and full of blubber, but they’re very muscular,” she says. “A lot of that body is intestines.” Without much insulation, manatees are very sensitive to temperature. If they swim in too-cold water long enough (anything under 68 F) they develop cold stress, which manifests outwardly in a frostbite-like icing of white, peeling tissue visible on the flippers and muzzles of many of the animals here. And if they stay even longer, they may develop pneumonia, hypothermia, and organ failure. Manatees typically migrate to warmer water during winter months, but those areas that could once support many manatees in a cold snap no longer have enough seagrass to feed them.
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<img alt="Manatee lies on plank floor and a person holds a tube near his face for feeding" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/tube-feeding_Corduroy.width-990_OFyYUuH.jpg"/>
<figcaption>Newly arrived adult manatee Corduroy is tube-fed at ZooTampa. Image courtesy of ZooTampa
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10:45 a.m. It’s feeding time (again) for the general manatee population housed at the front of the center in two broad pools backed by fake rock walls frequented by very real snowy egrets and great blue herons. Here, meals start at 7:30 a.m. and snacking continues almost without pause all day.On the path between the pools, Intern Olivia Callitsis is unloading heads of endive, escarole, and romaine lettuce from a pallet and stuffing them into a length of PVC pipe with a long hole in the side, so the greens spill out like a planter. A manatee consumes 10%-15% of its body weight daily, and occupants of the two main pools eat through some 1,200 pounds of produce a day. That makes the manatees the most expensive animals to feed at the zoo, costing some $40,000 a month. Burns says the money mostly comes from gate fees and private donors.With a gentle push, Callitsis launches the pipe into the pool, where it bobs gently before sinking. “You can throw it on the surface,” she says of the lettuce, “but this really mimics the natural environment. They have to dive down, work for it a little.” Soon, the surface is broken here and there by smooth gray backs and broad tails, then wrinkly, whiskery snouts munching intently.The inhabitants of the general population pools are mostly at the end of their stay here, with durations that average five months for adults and two years for calves. Because the goal is release, Vaccaro and her colleagues do not engage in the typical zoo enrichment activities, instead switching the manatees between pools frequently so they don’t get too used to their surroundings. And as soon as the calves are stable enough, Vaccaro buddies them up so they learn natural behaviors.
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<img alt="A woman drops a large pipe with protruding lettuce into a manatee pool" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/Animal_Care_Professional_Leesa_Whittlef_places.width-990_CV9i266.jpg"/>
<figcaption>Animal Care Professional Leesa Whittlef places a feeder full of lettuce into a critical-care manatee pool at ZooTampa. Image courtesy of ZooTampa
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2:00 p.m. It’s time for the second bottle feeding of the day. Innes and Sauseda carry bottles with a mix of vitamins, baby formula and oils like red palm fruit and macadamia to the medical pools. They lean over and slap the surface to get the calves’ attention and let them know where the goodies are. Small snouts appear and latch onto the bottles, clouds of formula spreading in the water.Burns is aware of the appeal of manatee calves in particular. “Everybody loves manatees and wants to help,” she says of the zoo’s visitors, but they don’t always connect their decisions at home with the fate of the animals they love. “Everyone wants that big, beautiful green lawn, perfectly manicured. But it comes at a cost.”She’s referring to the role nitrates from fertilizers play in <a href="https://www.pbs.org/wgbh/nova/article/florida-red-tide-gulf-coast/">fueling algae blooms</a>, which can block out the sunlight seagrass needs to survive. Similarly, pollution from agricultural runoff, construction, and sewer outflow can cloud coastal waters, starving out seagrass. Sick and dying grass can no longer stabilize the sea floor, which means even more sediment floats up into the water—compounding the situation and giving algae the upper hand, says Lead Biologist Ryan Brushwood of aquatic restoration company Sea &amp; Shoreline. What started as a little algae quickly grows, and ultimately the system hits an inflection point.  
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Some 70 miles north of Tampa, the community of Crystal River saw exactly what that looks like when, in the 1990s, an area that had once hosted some of the state’s largest seagrass meadows was overcome by muck and an algae called Lyngbya wollei. “There was no grass whatsoever,” remembers Lisa Moore, president of the non-profit Save Crystal River. “There were huge plumes of algae growing everywhere.” The water stank; dogs that swam in it got sick. And the population of manatees that had long flocked to the area for its warm springs found little food. In 2015, Save Crystal River hired Sea &amp; Shoreline for a multiyear project: sucking up millions of pounds of muck and water and treating it with a polymer that binds with particles suspended in the water so they become heavier and settle out. The leftover muck is taken to farms to use as fertilizer. Then, Brushwood and his colleagues plant new grass, which they keep in underwater cages to protect it from nibbling manatees until it is well established.Since the plant grows in rhizomes, underground shoots that extend long lateral stems in all directions, it can cover a lot of ground quickly. So far, Save Crystal River has replanted 300,000 plants covering 54 acres out of a planned 92—and those 54 acres have naturally expanded to over 200. The water is clearer, fish and crabs have returned—and so have manatees, in abundance. Save Crystal River hopes its model can be repeated elsewhere in Florida, perhaps including the Indian River Lagoon.  
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<img alt="A woman holds up a funnel and feeding tube that another woman uses to feed a manatee" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/Animal_Care_Supervisor_Jaime_Vaccaro_and_Anima.width-990_vLprW02.jpg"/>
<figcaption>Jaime Vaccaro and Sabrina Sauseda tube-feed manatee Kristoff, who has been lifted out of a medical pool with a hydrulic floor for feeding. Image courtesy of ZooTampa
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3:15 p.m. Vaccaro begins shifting manatees around in the medical pools, opening and closing the vertical gates to make space for Pebbles, a mostly-recovered adult who’s been at the center for close to a year. She was in critical condition when she was rescued, with cold stress and propeller wounds that weren’t healing. But she’s made a remarkable recovery and moved into the general population pool not long ago.Pebbles’ bloodwork has recently shown that she might have a brewing infection, though, so she’s receiving antibiotic injections. But after a few days of shots around the same time, Pebbles has figured out the pattern. Vaccaro slips into the water to try to isolate her into medical pool 3 but, in a flash, Pebbles breaks free, using the full force of her tail to twist through the open gate and into the shallow canal that connects the medical and general population pools. Vaccaro radios for help. “She knows she’s going to get an injection, and no one likes those,” Innes says. Instead, Pebbles plays a watery game of cat and mouse. Whenever Vaccaro moves toward her, she glides powerfully to the other side.After half an hour, the staff is on the verge of giving up, aware that Pebbles is stronger than they are. “We try not to force them to do anything they don’t want to do,” Innes says. “But these treatments save their lives, so we have to find that line of when to intervene.”4:25 p.m. As the winter sun starts to dip lower, Vaccaro prepares for the night, loading up PVC pipes full of lettuce and letting whole escarole heads thwap on the surface of medical pool 3 until it’s silty and bobbing with leaves. The buffet of greenery is enough to keep several hungry manatees fed into the wee hours, she reasons—plus, it might tempt Pebbles back into the pool on her own.4:30 p.m. To Vaccaro’s surprise, the tactic works. She moves quickly to drop the gate and hem Pebbles inside. 4:40 p.m. With the floor of medical pool 3 raised all the way up, the heads of lettuce are suddenly beached—and so is Pebbles. Vaccaro and a colleague cover her with a heavy mat, at times using their bodies to keep her steady. The first needle breaks, and Pebbles squirms away, but a second attempt to inject her succeeds. Vaccaro heaves a sigh of relief as Pebbles is lowered back into the pool.
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<img alt="A team loads a large blue sling containing a manatee into a truck" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/Loading_Chandler_for_release.width-990_NYhrGgJ.jpg"/>
<figcaption>A manatee named Chandler is loaded for release into the wild in January 2022. Chandler spent a year at ZooTampa's manatee critical care center after being brought in as a juvenile suffering from cold stress. Image courtesy of ZooTampa.
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4:55 p.m. The zoo is closing, but the center’s day never really ends. Vaccaro moves from her antibiotic triumph to mixing up formula for the calves in a cramped office behind the pools, then uses the waning light to tube-feed all three adult manatees in the medical pools in quick succession.When it’s recovering adult Flapjack’s turn, he lies quietly as the slurry of romaine lettuce and formula slips down his throat. He’s gained 70 pounds since he arrived, Sauseda says, showing a photo from the day he arrived with ribs protruding and belly sunken. The difference is still obvious between Flapjack and the other manatees, especially in the definition of his head and the slightness of his torso. But when Vaccaro and Sauseda finish feeding him, his eyes look somehow brighter.Florida made headlines this winter when it went ahead with a controversial program to <a href="https://www.palmbeachpost.com/story/weather/2021/12/08/fwc-oversee-feeding-plan-manatees-starving-death/8887866002/">feed wild manatees</a> in the Indian River Lagoon, in part with the hope of <a href="https://www.mysuncoast.com/2022/03/24/officials-florida-manatees-eat-every-scrap-food-trial/">helping individuals</a> like Flapjack so they don’t need to be treated at places like the center. In Burns’ mind, the most urgent question is how to stop the same thing that’s happened on the state’s Atlantic coast from repeating around Tampa, on the Gulf side. “Let’s learn from this,” she says. “We don’t want to wait for another largest death toll in a year. Let’s get ahead of it and make sure our animals have clean water.” State funds made available for water cleanup are a start, and education is a big part of any solution, she says. But such an urgent and entrenched problem needs a multipronged approach. “You can’t rely solely on education, on rehab, on laws—people break laws all the time. People have to work together in multiple ways to try to solve these problems.”As Flapjack returns to the water, Vaccaro pauses to make sure all her charges are breathing and swimming well after their feeding. She’s also made sure that every manatee has appropriate company overnight—no “busybody” animals that will annoy their poolmates, no males and females that might cause trouble together. Then she walks back to the office for final evening preparations and, eventually, to head home. The center finally lies calm in the half-dark, silent but for the lap of water and occasional hiss of a manatee’s breath. But someone will be back at 10 p.m to feed the calves.
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As Florida’s seagrass beds die off, manatees are starving. Can the seagrass–and the manatees–make a comeback?

A long exposure shows insects drawn to a halogen street light in the city of Mazatlán, Mexico. Image Credit: Matt Mawson, Getty Images

Why light pollution is a solvable environmental crisis

It’s not easy to make street lights exciting, but Kelly Beatty is trying. Holding court over Zoom on a spring evening in 2021, he warns citizens of Nantucket island in Massachusetts that the decisions they’ll soon make about their lights are choices they’re “going to have to live with for a long time.” Beatty often helps advise communities like Nantucket as they transition their streetlights from traditional bulbs to more energy-efficient LEDs, or light-emitting diodes. As communications officer of the Massachusetts chapter of the <a href="https://www.darksky.org">International Dark-Sky Association</a> (IDA), he’s well aware of the stakes. As this process has been repeated in towns across the world, it has led to a new and preventable environmental problem. LED lights can last 20 years or more, he reminds the group. “It’s important to get it right when you have a chance.”
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The IDA defines light pollution as the inappropriate or excessive use of artificial light, with variations including glare (excessive brightness that causes visual discomfort), skyglow (brightening of sky over inhabited areas) and light trespass (light that falls where it isn’t intended or needed). Already a growing problem, light pollution has intensified with the rise of LEDs, which produce blue-intense light in shorter wavelengths that are more susceptible to scatter and thus travel farther. An estimated 99% of U.S. and European populations now live under light-polluted skies, and one third of humanity is unable to see the Milky Way at night. From marine life and plants to birds and insects, the loss of darkness has left deep scars in our ecosystems.Twenty-five miles off the coast of Massachusetts, Nantucket is one of the darkest places left on the Eastern Seaboard—but even its skies are lightening. As they fight for their darkness, many Nantucketers taking up the cause see light pollution as the rare environmental threat where individual people can make a real difference. “It’s easier to solve than many of the other serious problems we have on Nantucket,” like erosion or affordable housing, says Gail Walker, founder of the local activist organization <a href="https://nantucketlights.org">Nantucket Lights</a>. “If we can educate people and help them understand the problems, most people are going to get on board.”
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<img alt="Silhouette of tree at night with city light behind and Milky Way in the sky" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/Nantucket_tree_at_night.width-990_CwescF7.jpg"/>
<figcaption>The night sky as seen from the Middle Moors on Nantucket. Image Credit: Bill Hoenk Photography
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The problem of light pollution started in earnest with the widespread installation of streetlights, which coincided with the rise of highways in the 1950s and 60s. “Think about society then: Everything closed at 8 or 9, and they rolled up the sidewalks,” Beatty says. “We did not have a 24/7 society like we have now.” With highways came all-night gas stations, drug stores, and grocery stores. And, above all, streetlights by the tens of millions. Then, in recent decades, lightbulbs made with LEDs arrived, a revolution in energy efficiency with seemingly little downside. After all, an LED bulb <a href="https://www.energy.gov/energysaver/led-lighting">converts some 90%</a> of the electricity it uses into light, whereas a conventional incandescent bulb only converts about 10%. And LED bulbs are touted as lasting up to 25 times longer.But the physics of LEDs make them fundamentally different from incandescents. While those traditional bulbs put out warm white light made of all colors mixed together, LEDs filter blue-rich light through a specialized phosphor material, producing light that appears white to the human eye but is still more blue-intense than incandescents’ light.But blue light is also the most disruptive to our nighttime environment because it mimics daylight, disrupting the hormone production and sleep cycles of both animals and humans. Melatonin, one of those hormones, helps the immune system destroy renegade cells dividing out of control. That can lead to other health issues, including heightened rates of cancer. And, “we’re not the only ones who produce melatonin,” says Mario Motta, a cardiologist and trustee of the American Medical Association. “Even amoebae produce melatonin”—meaning even amoebae might be vulnerable to light at night. 
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<img alt="Two geckos inside a lit up street lamp at night" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/GettyImages-1287021220_I8ybJf2.width-990_QaqcLnK.jpg"/>
<figcaption>Two geckos in an outdoor lamp in Córdoba, Spain. Studies indicate that insect predators like bats, lizards, and toads will station themselves near artificial lights, where they can easily pick off prey. Image Credit: Clemente Crisci / EyeEm, Getty Images
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The impacts of light pollution are evident everywhere from human health to astronomy research, but they come into particular focus in the recent phenomenon of global species die-offs. Between 100 million and a billion birds die every year due to light pollution, according to Massachusetts IDA chapter president James Lowenthal. New York City recently dealt with a huge die-off, “with flocks of migratory birds slamming into buildings,” says Sarah Bois, an ecologist at the island’s <a href="https://llnf.org">Linda Loring Nature Foundation</a> and a member of Nantucket Lights. “They’re attracted to light.” A 2015 study at New York’s 9/11 “Tribute in Light'' installation showed an increase from 500 birds within half a kilometer of the light beams before they were turned on to 15,700 just minutes after.The issue is a double whammy for birds because they rely on insects for food—and those populations are plummeting, with <a href="https://www.smithsonianmag.com/smart-news/light-pollution-contributes-insect-apocalypse-180973642/">light pollution contributing</a> significantly to the so-called “insect apocalypse.” By some estimates, one third of insects attracted to light sources at night die before morning, either due to exhaustion or because they get eaten. And according to a study in Germany, the number of insects in that country alone that die after being attracted to lights can number 100 billion or more in a single summer. Some starve to death searching for food that should appear bluer at twilight but is lit up amber under streetlights, says insect conservationist Avalon Owens, a doctoral candidate at Tufts University. Some are thrown off by light just the way we are, because of their circadian rhythms. Pollinators whose schedules are altered by artificial light miss the flowers they’re evolutionarily paired with, if the flowers naturally close and open with the warmth of the sun. And insects that rely on circadian rhythms for their yearly development don’t hibernate in time for winter and freeze to death.On Nantucket, these phenomena are of particular concern because the island is home to a remarkably healthy population of northern long-eared bats, which are endangered. Like many birds, the bats rely on insects for food and are easily dazzled by light, putting them in increasing jeopardy. Jack Dubinsky, director of the Maria Mitchell Aquarium on Nantucket, says he’s concerned that adding increasingly lit-up nights to the challenges of climate change, water quality, and ecosystem collapse could put huge pressure on some already struggling species. “The more curveballs we throw, the less likely they’ll be able to find their way,” he says.
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<img alt="Satellite image of U.S. at night, cities lit up" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/Light_pollution_US_map.width-990_FtftHWY.jpg"/>
<figcaption>A composite of nighttime images taken by the Suomi National Polar-orbiting Partnership satellite in 2012 shows light pollution in the contiguous United States. Image Credit: NASA Earth Observatory
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For Beatty, the first step in addressing the issues wrought by light pollution—and LEDs in particular—is to look at color temperature, which is measured in kelvins. Lower temperatures like 2,000 K correspond to warm reddish or yellowish light (think candlelight) while higher color temperatures like 4,500 K and up correspond to harsher, bluer light (think blue sky). “When LEDs started getting rolled out for streetlights, the most common ones were very close to this native, blue-rich light,” since they were also the most energy efficient, Beatty says.But because the white light of most LED bulbs is produced by coating a blue-intense LED in phosphor material, it’s possible to switch out that phosphor for one that absorbs and re-radiates the light to be less blue and look warmer, using the same technology already common in fluorescent bulbs. A new wave of LEDs, known as PC Amber, have color temperatures as low as 2,200 K and are gaining popularity.Beatty also points to another solution built into LED technology. Beyond being highly efficient, LED bulbs “can be controlled in amazing ways, programmed with central computers,” he says. Cities like Cambridge, Massachusetts, have programmed their LED streetlights to reduce to 50% power at various points during the night, depending on the street. A few towns in Europe have opted for motion-sensing lights that turn on and off as needed. Older-style lighting worked best if left on continuously through the night, Beatty says. But “LEDs don’t mind being turned on and off or dimmed up, down sideways, multiple times per second,” he says. “You can do anything you want to them.”
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In 2012, the American Medical Association <a href="https://www.mariomottamd.com/wp-content/uploads/AMA-Health-Effects-Light-at-Night.pdf">declared light at night carcinogenic</a>, which has helped drive policy change in cities across the country. New York City drew criticism from the IDA when it began replacing its streetlights with LED bulbs, some at color temperatures as high as 4,000 K, but changed tack when residents complained, citing the <a href="https://www.mariomottamd.com/wp-content/uploads/CSAPH_Report_02-A-16.pdf">AMA guidance</a>. (It helps that high-color-temperature lights are “universally hated,” Beatty says.) Since then, initiatives like Audubon’s Lights Out New York have also convinced managers of major structures like the Chrysler Building to go dark from midnight to dawn during the fall bird migration season. And the city has <a href="https://gothamist.com/arts-entertainment/how-nyc-audubon-helps-birds-disoriented-tribute-light-911">reached an agreement</a> to turn off for short periods the 9/11 memorial lights that were leading to so many avian deaths, allowing the trapped birds to continue their journey.In Chicago, which was famous in light pollution circles as the most over-lit city in the country, the city has been gradually replacing its streetlights with 3,000 K LEDs, which it  touted as saving the same energy as taking 2,400 cars off the road. Tucson, Arizona, reduced its lighting emissions by 60%, in part by switching to 3,000 K LEDs and programming them to dim late at night. And in fall 2021, Pittsburgh passed the nation’s first <a href="https://skyandtelescope.org/astronomy-news/pittsburgh-goes-dark-could-this-new-dark-sky-ordinance-begin-a-trend/">dark sky ordinance</a> that will involve replacing both its older-model conventional streetlights and more recently installed high-color-temperature LEDs with warmer, fully shielded lights equipped with motion sensors.
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<img alt="Teh city of phoenix glows yellow under a night sky" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/GettyImages-200547640-001.width-990_eBLDkCh.jpg"/>
<figcaption>Phoenix, Arizona, illuminated at night. In 1988, two astronomers noticed the brightening glow of nearby Tucson, Arizona, was threatening the dark skies at Kitt Peak National Observatory. They were "the first ones to raise the alarm about light pollution,” Kelly Beatty says. Image Credit: Andy Ryan, Getty Images
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Beatty encourages concerned citizens to get involved with local conversations about light at night—both about streetlights and policies around new construction. “The time to be proactive is when developments are being proposed,” he says, since it’s much easier to convince developers to make changes to their lighting plans when the buildings aren’t already set in literal stone. “Most times people install bad lighting because they don’t know any better,” he says. “It just takes one person to say ‘Hey, there’s another way to do this.’” That’s one reason he came to Nantucket’s meeting about streetlights.“We find the people most concerned about light pollution are not big cities but in rural areas,” he adds. And in that observation he sees a powerful advantage in the fight for dark skies. Since the causes of light pollution are hyperlocal, changes made by individuals and small groups can make a quick and observable difference, which empowers them to continue that work. “Every place where we can energize and educate local citizens is a victory, however small,” he says. “There are hundreds of people like me across the U.S. who are advocates for this, who insert themselves into local situations where education is desperately needed.”Gail Walker had already been watching Nantucket’s brightening skies when she learned about the IDA and its mission. The vivid stars over empty, windswept beaches had always been one of her favorite things about the island, and she wanted to preserve that experience for her grandchildren. Walker has earned a reputation locally as a go-getter, a retired attorney with a knack for bringing people around to her point of view. After coordinating the March 2021 forum on light pollution with Beatty, she began work in earnest with Nantucket Lights, bringing together concerned citizens to raise awareness and shape the community’s response.From there, conversations on the island evolved quickly. Walker began advising homeowners associations about their lighting policies, connecting local groups with lighting experts, and helping assess citizen complaints about lighting issues. She is also shepherding the community’s planned application to become an official International Dark-Sky Community.To be fair, Nantucket has a few key factors that give it an advantage in these efforts: a law governing outdoor lighting already on the books, an affluent community with an interest in maintaining a certain ambience on the island, and officials who see the benefit of that ambience for tourism. But to Walker, a significant part of her success so far is that light pollution “is a solvable problem.” Unlike other issues, which might seem too big, complex or intractable, she says, “there’s kind of an easy fix.”  Motta and Beatty suggest starting with the <a href="https://www.darksky.org/our-work/lighting/lighting-principles/">five principles</a> the IDA has established toward what Motta calls “sane outdoor lighting,” guidelines that individuals can follow to make better lighting choices in their own homes. Those guidelines include an emphasis on light that is useful, or toward a purpose; and targeted, or directed only where it's needed and otherwise properly shielded. Lights should also be no brighter than necessary. And it’s best to avoid high-color temperature, bluer light as much as possible. “That’s it,” Motta says. “Follow those simple rules, and we’ll have a much better world.”Owens, the entomologist, agrees. When it comes to adjusting our night light to help insects, “The most important thing is to ask, ‘Are you using the light?’” she says. “ If not, don’t have it.” She’s a proponent of flashlights, motion detectors, and timers, all the gadgets that might help keep light inside a building. “Automated curtain technology is the next big thing,” she jokes. “Who’s against closing your curtains? Nobody, but it’s hard to remember.”
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<img alt="The Milky Way extends straight up above an observatory dome" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/MilkyDome2.width-990_MGZpnNG.jpg"/>
<figcaption>The Milky Way stretches above the Maria Mitchell Association's Loines Observatory in Nantucket, Massachusetts. Image Credit: Charity Grace Mofsen
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On a breezy fall evening with a nip in the air, Nantucket’s <a href="https://www.mariamitchell.org">Maria Mitchell Association</a> is hosting about 50 visitors on the small platform between the domes of its observatory’s two telescopes—both currently trained on Jupiter to allow observers to admire its stripes. Overhead, clouds glide by soundlessly, reflecting a glow from the north that marks a grocery store and cluster of brightly lit schools. “You can see how they’re reflected up above, leaking up into the sky,” association Director of Astronomy Regina Jorgenson says, pointing. The distant light from Cape Cod is even visible occasionally, she says, on humid nights when moisture in the atmosphere scatters light farther.Still, in breaks in the mist, she’s able to point out the sugary trail of the Milky Way. The upturned faces of tonight’s crowd reflect awe at the sight. Many island visitors have never seen the Milky Way before. “The first time they see it, it’s a transformative experience for them,” she says.Jorgenson has been involved with the observatory since her internship here in 1997 and, along with her astronomy research, is dedicated to preserving the legacy of Maria Mitchell. Mitchell, America’s first professional woman astronomer, was born on the island in 1818. She gained fame for discovering a comet and became the first woman to be inducted into the American Academy of Arts and Sciences. Almost a century later, an NSF-funded internship at the observatory has become a key source of support for female astronomers in the U.S. Jorgenson is determined to protect that resource—and the dark sky that makes it possible. Watching the night grow inexorably brighter over the decades from her observatory perch outside town has been “scary” she says, but she remains hopeful. Nantucket’s geography, history, and culture makes so many things possible, she says. “We’re a small enough community that we have power to make a quick and effective change.” Correction: Nantucket is roughly 25 miles off the coast of Cape Cod, not 12 miles as previously stated.
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Excessive outdoor lighting is deadly to animals and takes a toll on human health and wellbeing, too. But when it comes to large-scale environmental problems, this one may be a relatively easy fix.

Russian spacewalkers explore the spherical Prichal docking module, which is attached to the Nauka multipurpose laboratory module of the International Space Station. Image credit: NASA Johnson, Flickr

Daily life on the International Space Station: A Q&A with a space archaeologist

Soon after photos started arriving from the International Space Station (ISS), Justin Walsh spotted something unexpected: frosting. Tucked into a plastic bag hanging off the station wall, near a can opener and bottle of ketchup, were telltale red, yellow, and green tubes. Walsh was mystified. “What does frosting imply? Baking,” he said recently over Zoom. But baking in space is pretty much impossible. 
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He got his resolution when astronaut Kayla Barron <a href="https://www.instagram.com/reel/CZmgSeupMuq/?utm_source=ig_web_copy_link">posted on Instagram</a> that she’d made a birthday cake for a colleague. “They did it by cutting the tops off of muffins and gluing them together with honey, then covering the whole thing with icing and frosting,” Walsh says. To Walsh, an art historian and archaeologist at Chapman University, the frosting was physical proof of something less concrete: astronauts’ bond with one another. Cooking and eating “is not only about sustenance; it's about social relations,” he says—even 250 miles above Earth. He, fellow space archaeologist Alice Gorman, and their colleagues received the frosting photo as part of the Sampling Quadrangle Assemblages Research Experiment, known as SQuARE. The ISS, which is administered by multiple space agencies, is essentially a <a href="https://www.nasa.gov/audience/forstudents/5-8/features/nasa-knows/what-is-the-iss-58.html">network of modules</a> for cooking, sleeping, science research, and other uses that’s slightly larger than a six-bedroom house. Between January and March, astronauts on board took daily photos of six carefully chosen sites around their temporary home first at the same time each day, then at random times. The project was an interstellar version of the archaeological technique known as quick testing, in which archaeologists divide a new site into a grid of one-meter squares and dig “test pits” that provide a basic sense of what they might find. In SQuARE, those “pits” are one-square-meter areas marked off with tape, scattered across the American, European, and Japanese modules of the ISS in areas used for work, science experiments, cooking, and hygiene. The team will analyze the resulting photos in hopes of understanding how each area is used over time and, from there, identify opportunities to improve space habitat design. NOVA talked with Walsh about the challenges of space archaeology and why astronauts eat so many tortillas. 
Alissa Greenberg: Usually, archaeologists excavate sites because it’s the only way to learn about life in those places—all the people are long dead. But we can talk to these astronauts. Why not do that?Justin Walsh: It's true that, for the most part, archaeologists do study the distant past. Contemporary archaeology developed starting in the 1970s. The first example of it was a project called the Tucson Garbage Project by a guy named William Rathje at the University of Arizona. He got the City of Tucson sanitation department to drop off samples of neighborhood garbage on a regular basis, and he and his graduate students went through it to understand the patterns of usage of different items.What's really fascinating about it is that they then went and interviewed people from the neighborhood about their consumption habits. So first of all, he found that people were throwing out lots of meat that they weren't using. So he was able to show that people were being wasteful with this particular commodity. But then he went to talk to people about these things, and he found out some interesting facts. Such as when you ask people questions, the way sociologists and anthropologists often do, they are not necessarily really good at articulating the realities of their lives—or they don't want to. Which is also perfectly fair and understandable! I would not blame them for that. But what it shows is that what archaeology can do is provide additional insights into human practices and that those insights don't have to be about the distant past.So, you can say, “Well why don't you just talk to the crew and ask?” or “Doesn't NASA document all that stuff?” Okay, we can absolutely do that, but that doesn't always work well—especially for astronauts, who are 100% good at staying on message and will not say anything to jeopardize their next flight to space. And as for the space agency, they don't do any forensic work on what's happened on the space station before. They're in the present and the future—and the past is gone. They're not thinking about what they can learn.
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<img alt="Mesh bags full of condiments and food items hang from a space station wall" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/iss066e130191_1.width-990_qW6eQSP.jpg"/>
<figcaption>One of the SQuARE sample locations, in a U.S. module galley area, marked by yellow tape at each corner. On the wall, mesh bags hold ketchup, Sriracha sauce, chocolate, and other food items. In the upper right corner are plastic bags holding tubes of frosting, which indicated that a kind of “space cooking” activity was happening in this location. Image courtesy of Justin Walsh
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AG: Why do you find space culture so compelling?JW: Because humans are doing things there in an environment that we are 100% not adapted for. We literally cannot survive. So, we have to come up with all these technologies that allow us to survive in that environment, living in microgravity. And on top of that, there's the other issues of confinement and isolation: the bad food, the distance from family and friends. How do they work together and live together? One of the phrases that I like is that a crewed spacecraft is “<a href="https://nap.nationalacademies.org/read/12387/chapter/1">a microsociety in a miniworld</a>.” You have the transmission of culture and traditions—"this is how we do things, this is how this is laid out”— being handed down almost from generation to generation. For example, on the ISS they have dinner together every Friday. Most of the time it's in the Russian service module; sometimes it's in the American service module. Or on ISS their food is carefully designed, and there are different kinds of traditions associated. Things like there's no bread, because crumbs are bad in space. If you inhale a crumb, that could really be a problem, so instead they use tortillas for everything. Tortillas don't make crumbs.AG: Can you talk about this most recent study? What’s the goal here?JW: We've been doing this study of historic photos that document life on the space station over 21 years. We've got this body of photographs, both published photographs from Flickr and also unpublished photographs that NASA has now given us—thousands and thousands of photographs. We've been working for the last three years to develop machine learning techniques that would allow the automated tagging of people, places, and objects in the photos. But they were taken essentially randomly. They weren't taken at precise intervals. How do we even characterize what the potential problems might be with that? One way is by doing an actually systematic survey of the material culture of the space station over the short term. That's what SQuARE is.
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<img alt="Photo of 3 astronauts with numbers labeling objects and people in the scene" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/iss018e043629_9452806214_o_v3.width-990_xdqMU3n.jpg"/>
<figcaption>A NASA astronaut, a JAXA astronaut, and a Hungarian-American space tourist pose in the Russian service module Zvezda in 2008. The wall behind them is decorated with items including flags, mission patches, portraits of Soviet space heroes, and Russian Orthodox religious objects such as painted icons. Image courtesy of Justin Walsh
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In archaeology, we take soil that’s all the same type, same color, same consistency, and different from what's above it and what's below it or what's adjacent to it, as a group that reflects a particular period of time. We take all of those items as relating to one another, and therefore they are separate from and need to be interpreted differently from what’s above or below. So we're treating each photo that way, because it is a slice of time, separate from the next day or the previous day.The fact that we're doing this one picture a day for each of six squares for 60 days, 360 images that were taken systematically at precisely defined locations, will allow us to better understand what the historic photos are all about. And likewise, what's happening in the historic photos—because there's so many of them and such a variety of things going on in them—will help us to interpret what we're seeing in the systematically recorded images.
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AG: What have you found so far?JW: We thought that the two experimental areas that we selected probably were not going to show very much change over time because they're basically just racks with scientific equipment. In fact, we were asked, “Are you sure you want to use those areas? Don’t you want to see where more activity is happening?” We had to say no because archaeology is not a treasure hunt. We want to actually see the full range. How would we be able to tell the difference between low activity and high activity if we’re only looking at high-activity areas?It turns out that one of those areas is seeing hardly any change. But in one of the other areas, we actually have seen a lot of things moving around. Things are being stored there, like laptops and a video camera. It seems to be kind of a staging area for what's happening next door, a veggie experiment. So that's really interesting, because that shows that when things aren't happening in the location, it can be repurposed.Another thing we’ve been seeing in the eating area is books. In one case there's been an actual physical book on the wall, just kind of stuck there for the time being—somebody put it down. But we've also seen an iPad with an e-book that was on. So, in a leisure moment, when you're eating by yourself, maybe you read a book or a magazine.The way it works right now is that there's this kind of plate hooked to an adjustable arm. And the plate has some Velcro on the front of it, so that the back of the iPad that has Velcro on it can be stuck to it. And that's fine, maybe that's a good enough solution. But now we have evidence of a different way in which the space is being used. And in future space habitat designs you might want to accommodate it in order to make a better experience. If nobody had evidence that this is how this is being done, we wouldn't even be able to think of solutions.
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<img alt="Two astronauts take a photo of themselves in a small mirror hanging on a cluttered wall of the space station" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/iss066e146542.width-990_gLFl5hC.jpg"/>
<figcaption>In an image of a SQuARE sample in a U.S. hygiene area, NASA astronauts Mark Vande Hei and Kayla Barron take a self-portrait in the mirror. Image courtesy of Justin Walsh
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Another aspect of the photo study—we placed a <a href="https://osf.io/preprints/socarxiv/ra4c3/">preprint of this on SocArXiv</a>—is we had all these images from Flickr, 8,000 of them, and helpfully NASA has captioned all of them. We were able to scrape them and peel out particular words: the names of the crew members and the locations. Just with those two pieces of data from each item, for the first time it's possible to map out where men and women are across the International Space Station by module. And if we look at nationality by module, it does seem like there are some real results. In the Russian segment, unsurprisingly, Russians make up the majority of people. And unsurprisingly, in the U.S. segment Americans make up the majority of people who are in those modules. So this indicates that in what claims to be an international space station, there are national zones. That's not something anybody has ever been able to show data for. Again, anecdotally you might have expected that to be the case. But we're able to show the reality. And this is because of the way the ISS is managed. Those are official designations. Each agency decides what happens in its own module and what their own crew do. So as a result, you end up with inefficiencies.AG: You’ve mentioned the future design of space habitats. Do you know if people doing that are watching your project? What kind of questions are they hoping you’ll answer?JW: The ISS is maybe the most expensive building project humans have ever undertaken. A staggering amount of money for one piece of architecture, and $3 billion or $4 billion on NASA alone to maintain it each year. I think that we're looking to be able to give more accurate and more precise descriptions of the functions of different areas and how that relates to what the originally designed and planned functions of those spaces are. It's really important to be able to understand whether people are using spaces the way they're intended. If they're not, how are they being used?We have at the moment four different commercial organizations that are planning, designing, building their own space stations, partly funded by NASA. And NASA and the other space agencies in ISS—except for the Russians—are currently already building a new space station that's going to go into orbit around the moon: Lunar Gateway. There are key problems that they're already focused on sorting out. But also, how do astronauts and designers create the conditions that mimic, or are as my colleague Alice says, are surrogates for, gravity? That is to say, handrails, bungee cords, Velcro, resealable bags. Where do we see Velcro building up over time? Those are areas where it might not have been foreseen, where it ended up that the crew realized that they were going to need more “gravity.” First of all, we have to identify those areas. And, second of all, then we have to understand why those areas are requiring “gravity,” because of the kinds of activities that are going on there. And then third, how do we anticipate that for future designs? Those kinds of questions, the space station companies really want to know that. Even when they have astronauts on their staff or in their executive boardroom, they still realize that there's a difference between anecdotes and data. So the really amazing thing about this is that, as (terrible pun) out of this world as this project is, it's the rare archaeological project that can actually have concrete and practical implications for the future.This interview has been edited for length and clarity.Correction: Due to a punctuation error, a previous version of this article indicated that the Russian space agency was building Lunar Gateway. It is actually a project of the four non-Russian ISS space agencies.
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Archaeologists are working to understand how astronauts really use their space on the ISS—and help improve space habitats of the future.

Quinn Brett hikes with her Bomber off-road handcycle on Walter's Wiggles, a steep trail named for its many switchbacks, in Zion National Park. Image Courtesy of Quinn Brett

Adapting national parks for wheelchair hiking

The trails through our public lands weren’t designed for wheelchairs, but new wheelchairs are designed for those trails. National Park Service accessibility specialist Quinn Brett wants parks to catch up with wheelchair technology, increasing access to American wilderness.

6 stinking cool facts about dog noses

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Did you know that dogs can use their cold, wet (and cute!) noses to sense sources of heat and thermal radiation? That discovery, via a <a href="https://www.science.org/content/article/new-sense-discovered-dog-noses-ability-detect-heat">2020 study from Sweden</a> that challenged dogs to choose between a warm and cool object across a room, makes them only the second mammal known to possess that superpower. (The other is a vampire bat.)And that’s not all dogs' noses can do. Read on for six reasons why dog noses are among nature’s most amazingly engineered instruments—instruments whose power humans are <a href="https://www.pbs.org/wgbh/nova/video/electronic-nose-imitate-dog-nose/">now trying to recreate</a>: 1. Dogs' <a href="https://www.pbs.org/wgbh/nova/article/dogs-sense-of-smell/">sense of smell</a> is between 10,000 and 100,000 times as potent as humans’. This power comes in part from the up to 300 million olfactory receptors dogs carry around in their noses, compared to our mere 6 million. And the part of the canine brain that is dedicated to smells is 40 times larger than ours, proportionally speaking. 2. Dogs can smell continuously, even while they’re breathing in and out. In contrast, when a human smells a scent (sniffs a rose, for example) we inhale that odor and breathe in oxygen through the same passage. But if a dog smells the same flower, air “splits into two different flow paths, one for olfaction and one for respiration," Brent Craven, a Pennsylvania State University bioengineer who has modeled <a href="https://anatomypubs.onlinelibrary.wiley.com/doi/full/10.1002/ar.20592">canine olfaction anatomy</a> using high-resolution MRIs, <a href="https://www.pbs.org/wgbh/nova/article/dogs-sense-of-smell/">told NOVA</a>.Craven and his colleagues found that a portion of the air dogs inhale gets ushered into a specialized area at the back of the canine nose reserved for odor detection, while the rest of it continues rushing toward the lungs. And when dogs exhale, that air departs through nose slits in a unique aerodynamic pattern that also guides new air in, creating a cycle of breath that continuously supplies the in-house laboratory in the back of the canine nose with new material. In <a href="https://pubmed.ncbi.nlm.nih.gov/8735662/">one study from the University of Oslo</a>, a dog on a hunt sniffed continuously for a full 40 seconds, across 30 respiratory cycles!<h4>Watch: This Device Smells Diseases by Imitating a Dog's Nose</h4>
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3. Dogs can <a href="https://vcahospitals.com/know-your-pet/how-dogs-use-smell-to-perceive-the-world">wiggle their nostrils independently</a>, which helps them figure out which direction a scent is coming from. Humans can only wiggle their nostrils simultaneously. (Try it. We’ll wait.)4. Dogs are great at interpreting all the information coming in through their noses in fine detail. In her book “Inside of a Dog,” canine cognition researcher Alexandra Horowitz writes that humans might taste a teaspoon of sugar added to a cup of coffee. But a dog could detect the same teaspoon of sugar in a million gallons of water—enough to fill two Olympic-sized pools.And to take the sugar metaphor further, “if we humans walk into a bakery, we can say, ‘someone’s baking a pie in here,’” canine search specialist Lynne Engelbert <a href="https://www.pbs.org/wgbh/nova/article/cremation-ashes-sniffing-dogs-california-wildfire/">told NOVA</a>. “A dog would walk in and say, ‘Oh, someone’s baking a pie in here, and it has apples, and butter, and cinnamon, and nutmeg.”
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5. Dogs can connect a human with the scent they leave behind with exceptional precision—and even help diagnose sick humans with a variety of diseases. Forensic chemist Ken Furton, who has studied dog olfaction for more than 25 years, once blew up a car with colleagues and then asked detection dogs to pick out human scent from the resulting debris. The dogs were able to sniff the small amount of shrapnel and correctly identify the people who had been in contact with the bomb pre-explosion 82% of the time.More recently, Furton and his colleagues looked at whether dogs might be trained to identify COVID-19 patients—and found they could do so with 97.5% accuracy. “I was shocked,” he told NOVA. And <a href="https://faseb.onlinelibrary.wiley.com/doi/abs/10.1096/fasebj.2019.33.1_supplement.635.10">one 2019 study</a> indicated humans’ best friends can sniff out cancer with a similarly high 97% accuracy rate.<h4>Watch: Cannabis-Sniffing K-9's: Out of a Job?</h4>
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 6. Dogs can not only identify human remains–they can sniff out already cremated remains from among other ashes. Dogs in the American West are now being trained to <a href="https://www.pbs.org/wgbh/nova/article/cremation-ashes-sniffing-dogs-california-wildfire/">look for the cremated remains</a> of homeowners’ loved ones when those homes are lost to the region's increasingly fierce wildfires. The non-profit Alta Heritage Foundation brings specially trained search dogs and archaeologists to the site of a house destroyed by fire, using canine colleagues to narrow down where the lost ashes might be buried and then archeological techniques to excavate them. The ashes are often the only thing his clients want to recover from their houses, Alta Heritage founder Alex DeGeorgey told NOVA. So being able to find their loved ones’ ashes within the ashes of a house is both powerful and continually surprising. “I’ve done this hundreds of times,” DeGeorgey says of cremation ash recovery, “and I still marvel that we’re able to do it.”
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