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Pocket gophers certainly don’t qualify as card-carrying 4-H members, but the rodents might be farming roots in the open air of their moist, nutrient-rich tunnels.

The gophers subsist mostly on roots encountered in the tunnels that the rodents excavate. But the local terrain doesn’t always provide enough roots to sustain gophers, two researchers report in the July 11 Current Biology. To make up the deficit, the gophers practice a simple type of agriculture by creating conditions that promote more root growth, suggest ecologist Jack Putz of the University of Florida in Gainesville and his former zoology undergraduate student Veronica Selden.
But some scientists think it’s a stretch to call the rodents’ activity farming. Gophers aren’t actively working the soil, these researchers say, but inadvertently altering the environment as the rodents eat and poop their way around — much like all animals do.

Tunnel digging takes a lot of energy — up to 3,400 times as much as walking along the surface for gophers. To see how the critters were getting all this energy, Selden and Putz in 2021 began investigating the tunnels of southeastern pocket gophers (Geomys pinetis) in an area being restored to longleaf pine savanna in Florida that Putz partially owns.

The pair took root samples from soil adjacent to 12 gopher tunnels and extrapolated how much root mass a gopher would encounter as it excavated a meter of tunnel. Then the researchers calculated the amount of energy that those roots would provide.

“We were able to compare energy cost versus gain, and found that on average there is a deficit, with about half the cost of digging being unaccounted for,” Selden says.

Upon examining some tunnels, Selden and Putz saw gopher feces spread through the interior along with signs of little bites taken out of roots and churning of the soil.

The gophers, the researchers conclude, provide conditions that favor root growth by spreading their own waste as fertilizer, aerating the soil and repeatedly nibbling on roots to encourage new sprouting.
“All of these activities encourage root growth, and once the roots grow into the tunnels, the gophers crop the roots,” Selden says. She and Putz say that this amounts to a rudimentary form of farming. If so, gophers would be the first nonhuman mammals to be recognized as farmers, Putz says. Other organisms, such as some insects, also farm food and started doing so much earlier than humans (SN: 4/23/20).

But the study has its skeptics. “I don’t really think you can call it farming per the human definition. All herbivores eat plants, and everybody poops,” says J.T. Pynne, a wildlife biologist at the Georgia Wildlife Federation in Covington who studies southeastern pocket gophers. So the root nibbling and tunnel feces might not be signs of agriculture, just gophers doing what all animals do.

Evolutionary biologist Ulrich Mueller agrees. “If we accept the tenuous evidence presented in the Selden article as evidence for farming … then most mammals and most birds are farmers because each of them accidentally have also some beneficial effects on some plants that these mammals or birds also feed on,” he says.

Not only that, but the study is also dangerous, says Mueller, of the University of Texas at Austin. The public will see through “the shallowness of the data,” he says, and will conclude that science is “just a bunch of storytelling, eroding general trust in science.”

For her part, Selden says she understands that because gophers don’t plant their crops, not everyone is comfortable calling them farmers. Still, she argues that “what qualifies the gophers as farmers and sets them apart from, say, cattle, which incidentally fertilize the grass they eat with their wastes, is that gophers cultivate and maintain this ideal environment for roots to grow into.”

At the very least, Putz says, he hopes their research makes people kinder toward the rodents. “If you go to the web and put in ‘pocket gopher,’ you’ll see more ways to kill them than you can count.”

Humans have long tried to wrangle water. We’ve straightened once-meandering rivers for shipping purposes. We’ve constructed levees along rivers and lakes to protect people from flooding. We’ve erected entire cities on drained and filled-in wetlands. We’ve built dams on rivers to hoard water for later use.

“Water seems malleable, cooperative, willing to flow where we direct it,” environmental journalist Erica Gies writes in Water Always Wins. But it’s not, she argues.

Levees, which narrow channels causing water to flow higher and faster, nearly always break. Cities on former wetlands flood regularly — often catastrophically. Dams starve downstream environs of sediment needed to protect coastal areas against rising seas. Straightened streams flow faster than meandering ones, scouring away riverbed ecosystems and giving water less time to seep downward and replenish groundwater supplies.

In addition to laying out this damage done by supposed water control, Gies takes readers on a hopeful global tour of solutions to these woes. Along the way, she introduces “water detectives”— scientists, engineers, urban planners and many others who, instead of trying to control water, ask: What does water want?
These water detectives have found ways to give the slippery substance the time and space it needs to trickle underground. Around Seattle’s Thornton Creek, for instance, reclaimed land now allows for regular flooding, which has rejuvenated depleted riverbed habitat and created an urban oasis. In California’s Central Valley, scientists want to find ways to shunt unpolluted stormwater into ancient, sediment-filled subsurface canyons that make ideal aquifers. Feeding groundwater supplies will in turn nourish rivers from below, helping to maintain water levels and ecosystems.

While some people are exploring new ways to manage water, others are leaning on ancestral knowledge. Without the use of hydrologic mapping tools, Indigenous peoples of the Andes have a detailed understanding of the plumbing that links surface waters with underground storage. Researchers in Peru are now studying Indigenous methods of water storage, which don’t require dams, in hopes of ensuring a steady flow of water to Lima — Peru’s populous capital that’s periodically afflicted by water scarcity. These studies may help convince those steeped in concrete-centric solutions to try something new. “Decision makers come from a culture of concrete,” Gies writes, in which dams, pipes and desalination plants are standard.

Understanding how to work with, not against, water will help humankind weather this age of drought and deluge that’s being exacerbated by climate change. Controlling water, Gies convincingly argues, is an illusion. Instead, we must learn to live within our water means because water will undoubtedly win.

Biologist Martin Dančák didn’t set out to find a plant species new to science. But on a hike through a rainforest in Borneo, he and colleagues stumbled on a subterranean surprise.

Hidden beneath the soil and inside dark, mossy pockets below tree roots, carnivorous pitcher plants dangled their deathtraps underground. The pitchers can look like hollow eggplants and probably lure unsuspecting prey into their sewer hole-like traps. Once an ant or a beetle steps in, the insect falls to its death, drowning in a stew of digestive juices (SN: 11/22/16). Until now, scientists had never observed pitcher plants with traps almost exclusively entombed in earth.
“We were, of course, astonished as nobody would expect that a pitcher plant with underground traps could exist,” says Dančák, of Palacký University in Olomouc, Czech Republic.

That’s because pitchers tend to be fragile. But the new species’ hidden traps have fleshy walls that may help them push against soil as they grow underground, Dančák and colleagues report June 23 in PhytoKeys. Because the buried pitchers stay concealed from sight, the team named the species Nepenthes pudica, a nod to the Latin word for bashful.

The work “highlights how much biodiversity still exists that we haven’t fully discovered,” says Leonora Bittleston, a biologist at Boise State University in Idaho who was not involved with the study. It’s possible that other pitcher plant species may have traps lurking underground and scientists just haven’t noticed yet, she says. “I think a lot of people don’t really dig down.”

The next generation of dark matter detectors has arrived.

A massive new effort to detect the elusive substance has reported its first results. Following a time-honored tradition of dark matter hunters, the experiment, called LZ, didn’t find dark matter. But it has done that better than ever before, physicists report July 7 in a virtual webinar and a paper posted on LZ’s website. And with several additional years of data-taking planned from LZ and other experiments like it, physicists are hopeful they’ll finally get a glimpse of dark matter.
“Dark matter remains one of the biggest mysteries in particle physics today,” LZ spokesperson Hugh Lippincott, a physicist at the University of California, Santa Barbara said during the webinar.

LZ, or LUX-ZEPLIN, aims to discover the unidentified particles that are thought to make up most of the universe’s matter. Although no one has ever conclusively detected a particle of dark matter, its influence on the universe can be seen in the motions of stars and galaxies, and via other cosmic observations (SN: 7/24/18).

Located about 1.5 kilometers underground at the Sanford Underground Research Facility in Lead, S.D., the detector is filled with 10 metric tons of liquid xenon. If dark matter particles crash into the nuclei of any of those xenon atoms, they would produce flashes of light that the detector would pick up.

The LZ experiment is one of a new generation of bigger, badder dark matter detectors based on liquid xenon, which also includes XENONnT in Gran Sasso National Laboratory in Italy and PandaX-4T in the China Jinping Underground Laboratory. The experiments aim to detect a theorized type of dark matter called Weakly Interacting Massive Particles, or WIMPs (SN: 12/13/16). Scientists scaled up the search to allow for a better chance of spying the particles, with each detector containing multiple tons of liquid xenon.

Using only about 60 days’ worth of data, LZ has already surpassed earlier efforts to pin down WIMPs (SN: 5/28/18). “It’s really impressive what they’ve been able to pull off; it’s a technological marvel,” says theoretical physicist Dan Hooper of Fermilab in Batavia, Ill, who was not involved with the study.

Although LZ’s search came up empty, “the way something’s going to be discovered is when you have multiple years in a row of running,” says LZ collaborator Matthew Szydagis, a physicist at the University at Albany in New York. LZ is expected to run for about five years, and data from that extended period may provide physicists’ best chance to find the particles.

Now that the detector has proven its potential, says LZ physicist Kevin Lesko of Lawrence Berkeley National Laboratory in California, “we’re excited about what we’re going to see.”

Tyrannosaurus rex’s tiny arms have launched a thousand sarcastic memes: I love you this much; can you pass the salt?; row, row, row your … oh.

But back off, snarky jokesters. A newfound species of big-headed carnivorous dinosaur with tiny forelimbs suggests those arms weren’t just an evolutionary punchline. Arm reduction — alongside giant heads — evolved independently in different dinosaur lineages, researchers report July 7 in Current Biology.

Meraxes gigas, named for a dragon in George R. R. Martin’s “A Song of Ice and Fire” book series, lived between 100 million and 90 million years ago in what’s now Argentina, says Juan Canale, a paleontologist with the country’s CONICET research network who is based in Buenos Aires. Despite the resemblance to T. rex, M. gigas wasn’t a tyrannosaur; it was a carcharodontosaur — a member of a distantly related, lesser-known group of predatory theropod dinosaurs. M. gigas went extinct nearly 20 million years before T. rex walked on Earth.
The M. gigas individual described by Canale and colleagues was about 45 years old and weighed more than four metric tons when it died, they estimate. The fossilized specimen is about 11 meters long, and its skull is heavily ornamented with crests and bumps and tiny hornlets, ornamentations that probably helped attract mates.

Why these dinosaurs had such tiny arms is an enduring mystery. They weren’t for hunting: Both T. rex and M. gigas used their massive heads to hunt prey (SN: 10/22/18). The arms may have shrunk so they were out of the way during the frenzy of group feeding on carcasses.

But, Canale says, M. gigas’ arms were surprisingly muscular, suggesting they were more than just an inconvenient limb. One possibility is that the arms helped lift the animal from a reclining to a standing position. Another is that they aided in mating — perhaps showing a mate some love.

Getting a COVID-19 test has become a regular part of many college students’ lives. That ritual may protect not just those students’ classmates and professors but also their municipal bus drivers, neighbors and other members of the local community, a new study suggests.

Counties where colleges and universities did COVID-19 testing saw fewer COVID-19 cases and deaths than ones with schools that did not do any testing in the fall of 2020, researchers report June 23 in PLOS Digital Health. While previous analyses have shown that counties with colleges that brought students back to campus had more COVID-19 cases than those that continued online instruction, this is the first look at the impact of campus testing on those communities on a national scale (SN: 2/23/21).
“It’s tough to think of universities as just silos within cities; it’s just much more permeable than that,” says Brennan Klein, a network scientist at Northeastern University in Boston.

Colleges that tested their students generally did not see significantly lower case counts than schools that didn’t do testing, Klein and his colleagues found. But the communities surrounding these schools did see fewer cases and deaths. That’s because towns with colleges conducting regular testing had a more accurate sense of how much COVID-19 was circulating in their communities, Klein says, which allowed those towns to understand the risk level and put masking policies and other mitigation strategies in place.

The results highlight the crucial role testing can continue to play as students return to campus this fall, says Sam Scarpino, vice president of pathogen surveillance at the Rockefeller Foundation’s Pandemic Prevention Institute in Washington, D.C. Testing “may not be optional in the fall if we want to keep colleges and universities open safely,” he says.
Finding a flight path
As SARS-CoV-2, the virus that causes COVID-19 rapidly spread around the world in the spring of 2020, it had a swift impact on U.S. college students. Most were abruptly sent home from their dorm rooms, lecture halls, study abroad programs and even spring break outings to spend what would be the remainder of the semester online. And with the start of the fall semester just months away, schools were “flying blind” as to how to bring students back to campus safely, Klein says.

That fall, Klein, Scarpino and their collaborators began to put together a potential flight path for schools by collecting data from COVID-19 dashboards created by universities and the counties surrounding those schools to track cases. The researchers classified schools based on whether they had opted for entirely online learning or in-person teaching. They then divided the schools with in-person learning based on whether they did any testing.

It’s not a perfect comparison, Klein says, because this method groups schools that did one round of testing with those that did consistent surveillance testing. But the team’s analyses still generally show how colleges’ pandemic response impacted their local communities.

Overall, counties with colleges saw more cases and deaths than counties without schools. However, testing helped minimize the increase in cases and deaths. During the fall semester, from August to December, counties with colleges that did testing saw on average 14 fewer deaths per 100,000 people than counties with colleges that brought students back with no testing — 56 deaths per 100,000 versus about 70.
The University of Massachusetts Amherst, with nearly 30,000 undergraduate and graduate students in 2020, is one case study of the value of the testing, Klein says. Throughout the fall semester, the school tested students twice a week. That meant that three times as many tests occurred in the city of Amherst than in neighboring cities, he says. For much of the fall and winter, Amherst had fewer COVID-19 cases per 1,000 residents than its neighboring counties and statewide averages.

Once students left for winter break, campus testing stopped – so overall local testing dropped. When students returned for spring semester in February 2021, area cases spiked — possibly driven by students bringing the coronavirus back from their travels and by being exposed to local residents whose cases may have been missed due to the drop in local testing. Students returned “to a town that has more COVID than they realize” Klein says.

Renewed campus testing not only picked up the spike but quickly prompted mitigation strategies. The university moved classes to Zoom and asked students to remain in their rooms, at one point even telling them that they should not go on walks outdoors. By mid-March, the university reduced the spread of cases on campus and the town once again had a lower COVID-19 case rate than its neighbors for the remainder of the semester, the team found.

The value of testing
It’s helpful to know that testing overall helped protect local communities, says David Paltiel, a public health researcher at the Yale School of Public Health who was not involved with the study. Paltiel was one of the first researchers to call for routine testing on college campuses, regardless of whether students had symptoms.

“I believe that testing and masking and all those things probably were really useful, because in the fall of 2020 we didn’t have a vaccine yet,” he says. Quickly identifying cases and isolating affected students, he adds, was key at the time.
But each school is unique, he says, and the benefit of testing probably varied between schools. And today, two and a half years into the pandemic, the cost-benefit calculation is different now that vaccines are widely available and schools are faced with newer variants of SARS-CoV-2. Some of those variants spread so quickly that even testing twice a week may not catch all cases on campus quickly enough to stop their spread, he says.

As colleges and universities prepare for the fall 2022 semester, he would recommend schools consider testing students as they return to campus with less frequent follow-up surveillance testing to “make sure things aren’t spinning crazy out of control.”

Still, the study shows that regular campus testing can benefit the broader community, Scarpino says. In fact, he hopes to capitalize on the interest in testing for COVID-19 to roll out more expansive public health testing for multiple respiratory viruses, including the flu, in places like college campuses. In addition to PCR tests — the kind that involve sticking a swab up your nose — such efforts might also analyze wastewater and air within buildings for pathogens (SN: 05/28/20).

Unchecked coronavirus transmission continues to disrupt lives — in the United States and globally — and new variants will continue to emerge, he says. “We need to be prepared for another surge of SARS-CoV-2 in the fall when the schools reopen, and we’re back in respiratory season.”

Emerald jewel wasps know what cockroach brains feel like.

This comes in handy when a female wasp needs to turn a cockroach into an obedient zombie that will host her larvae and serve as dinner. First, the wasp plunges its stinger into the cock­roach’s midsection to briefly paralyze the legs. Next comes a more delicate operation: stinging the head to deliver a dose of venom to specific nerve cells in the brain, which gives the wasp control over where its victim goes. But how does a wasp know when it’s reached the brain? The stinger’s tip is a sensory probe. In experiments using brainless cockroaches, a wasp will sting the head over and over again, searching fruitlessly for its desired target.

A brain-feeling stinger is just one example of the myriad ways animals sense the world around them. We humans tend to think the world is as we perceive it. But for everything that we can see, smell, taste, hear or touch, there’s so much more that we’re oblivious to.

In An Immense World, science journalist Ed Yong introduces that hidden world and the concept of Umwelt, a German word that refers to the parts of the environment an animal senses and experiences. Every creature has its own Umwelt. In a room filled with different types of organisms, or even multiple people, each individual would experience that shared atmo­sphere in wholly different ways.

Yong eases readers into the truly immense world of senses by starting with ones that we are intimately familiar with. In some cases, he tests the limits of his own abilities. Dog noses, for instance, are better than human noses at sniffing out a scent long after the source is gone, as Yong demonstrates. While crawling around on his hands and knees with his eyes closed, he was able to track a chocolate-scented string that a researcher had put on the ground. But he lost the scent when the string was removed. That wouldn’t happen to a dog. It would pick up the trace, string or no string.
In exploring the vast sensory world, it helps to have a good imagination, as even familiar senses can seem quite strange. Scallops, for instance, have eyes and somehow “see” despite having a crude brain that can’t process the images. Crickets have hairs that are so responsive to an approaching spider that trying to make the hairs more sensitive might break the rules of physics. A blind Ecuadorian catfish senses raging water with durable teeth that cover its skin. The animal uses the dentures to find calmer waters.

Going through these imagination warm-up exercises makes it somewhat easier to ponder what it might be like to be an echolocating bat, a bird that detects magnetic fields or a fish that communicates using electricity. Yong’s vivid descriptions also help readers fathom these senses: “A river full of electric fish must be like a cocktail party where no one ever shuts up, even when their mouths are full.” In a forest, foliage may seem largely silent, but some insects “talk” through plant stems using vibration. With headphones hooked up to plants so that scientists can listen in, “chirping cicadas sound like cows and katydids sound like revving chainsaws.”

For all the book’s wonder, the last chapter brings readers crashing back to today’s reality. Humans are polluting animals’ Umwelten; we’re forcing animals to exist in environments con­taminated with human-made stimuli. And the consequences can be deadly, Yong warns. Adding artificial light in the dark­ness of night is killing birds and insects (SN: 8/31/21). Making environments louder is masking the sounds of preda­tors and forcing prey to spend more time keeping an eye out than eating (SN: 5/4/17). “We are closer than ever to understanding what it is like to be another animal,” Yong writes, “but we have made it harder than ever for other animals to be.”

Since each of us has our own Umwelt, fully understand­ing the foreign worlds of animals is close to impossible, Yong writes. How do we know, for instance, which animals feel pain? Researchers can dissect the signals or stimuli an ani­mal might receive. But what that creature experiences often remains a mystery.

In the quest to measure the fundamental constant that governs the strength of gravity, scientists are getting a wiggle on.

Using a pair of meter-long, vibrating metal beams, scientists have made a new measurement of “Big G,” also known as Newton’s gravitational constant, researchers report July 11 in Nature Physics. The technique could help physicists get a better handle on the poorly measured constant.

Big G is notoriously difficult to determine (SN: 9/12/13). Previous estimates of the constant disagree with one another, leaving scientists in a muddle over its true value. It is the least precisely known of the fundamental constants, a group of numbers that commonly show up in equations, making them a prime target for precise measurements.
Because the vibrating beam test is a new type of experiment, “it might help to understand what’s really going on,” says engineer and physicist Jürg Dual of ETH Zurich.

The researchers repeatedly bent one of the beams back and forth and used lasers to measure how the second beam responded to the first beam’s varying gravitational pull. To help maintain a stable temperature and avoid external vibrations that could stymie the experiment, the researchers performed their work 80 meters underground, in what was once a military fortress in the Swiss Alps.

Big G, according to the new measurement, is approximately 6.82 x 10-11 meters cubed per kilogram per square second. But the estimate has an uncertainty of about 1.6 percent, which is large compared to other measurements (SN: 8/29/18). So the number is not yet precise enough to sway the debate over Big G’s value. But the team now plans to improve their measurement, for example by adding a modified version of the test with rotating bars. That might help cut down on Big G’s wiggle room.

Demond “Dom” Mullins’ days as a student at Lehman College in New York were interrupted in 2004 when his National Guard unit was deployed to Baghdad. A year later, he returned home but struggled with depression and rage. Immersing himself in his studies helped him make sense of the world and his experiences. After completing degrees in Africana studies and political science, Mullins earned a Ph.D. in sociology, focusing his research on a subject he knew firsthand: how returning veterans reintegrate into society.

In 2015, the avid climber and adventure sportsman joined six other veterans and a journalist on a monthlong excursion to climb Alaska’s Denali, the highest peak in North America. To understand the health benefits of high-risk outdoor adventuring outside the clinical therapy framework, Mullins interviewed each participant and collected data about group cohesion and the impact of such high-risk activities on social bonds for his study “Veterans Expeditions: Tapping the great outdoors.”

Formerly an adjunct assistant professor at the Cooper Union for the Advancement of Science and Art in New York City, Mullins has climbed Kilimanjaro and Mount Kenya. In May, he tackled his biggest climbing challenge yet: summiting Mount Everest, the world’s tallest mountain. He and seven other members of Full Circle Everest, an all-Black mountaineering team, set out to make history. Seven of them reached the summit, coming very close to doubling the number of Black people who have achieved that feat.
Science News asked Mullins, while he was preparing for the climb, about his research and why he wants more Black people in outdoor spaces. This interview was edited for clarity and length.

SN: When you returned home from Iraq, you cut yourself off from others and contemplated ending your life. What helped you get through the worst times?

Mullins: Education. I was grappling with the discontents of coming home and struggling with what I had experienced in the Iraq War. Education allowed me to explore aspects of my experience intellectually through things that really engaged me — history and social theory.

SN: Did the war change what you envisioned for yourself academically?

Mullins: It influenced my trajectory. Graduate school was not even on my radar before. When I came home, I had this great urgency to improve my future, learn more about global politics and understand how history could produce such a moment. I also wanted to know how all of that might influence veterans’ reintegration.

SN: How did the Denali research expedition follow on your work on veteran reintegration?

I became an avid mountaineer, rock and ice climber and began training with Veterans Expeditions [a nonprofit that works to enhance the life of U.S. veterans]. By the time the Denali expedition came about in May 2015, the cofounder [Nick Watson] asked me to be a part of it. I wanted to tell the story of veterans summiting Denali in a way that makes sense, was scientifically rigorous and could contribute to the research. I wanted to answer certain questions about how interventions like hiking and climbing might come into play. Ethnography [the study of people in their environment] was the best way to do that.

SN: What did you learn about veterans and outdoor adventuring?

Mullins: Much more than in the past, my generation of veterans is more willing to talk about their experiences with each other to find affinity and solidarity. After leaving the service, some lose their identity, partly because there is no space reserved for them to perform the identities they have cultivated through military training, socialization and performance. I learned that they engage in these kinds of high-risk sporting events to support their identities. The outdoors is sort of a theater to perform the heroic identities they’ve developed in a way that can be conducive to greater physical and communal health. One veteran said to me, “The rock and the ice don’t lie to me.” He was reasserting that he is a warrior.
SN: How did you become a part of Full Circle Everest?

Mullins: Through Veterans Expeditions, I developed a relationship with [world-famous mountaineer] Conrad Anker. Conrad had this idea about putting together an all-Black expedition to Everest. He introduced me to [Full Circle expedition leader and organizer] Philip Henderson, who had been considering this for a long time. I met Phil and knew right away that I wanted to be a part of that expedition and help find other athletes.

SN: What, if anything, about your experience on Denali do you believe will benefit your attempt to summit Mount Everest?

Mullins: Everest is 9,000 feet taller than Denali. It’s a longer pursuit and a longer expedition, but the conditions will be similar. We got snowed in on Denali for 17 days, which I believe has prepared me for my expedition with Full Circle.

This pursuit is about developing relationships with people who have common experiences. It’s having someone who gets your drift, who understands what you mean without you needing to explain everything. It’s about building community and feeling like you belong. People want to feel like the group is better as a result of their participation. It’s all about social cohesion.

SN: Will you be conducting research on this expedition?

Mullins: This time, I’ll be studying myself — doing an autoethnography. I took time off from work to do this climb, so I don’t have any pressing job to get back to. I plan to take some time to reflect and write about this once it’s over, to help people understand the value of it for me.
SN: The Full Circle team spent a few weeks together in January at the Khumbu Climbing Center in Nepal. Your teammates went home, then came back in April to start the climb, but you stayed in Nepal. Why?

Mullins: It gives me an edge in so many different ways: having time for my body to properly acclimate to the elevation, understanding how to keep myself safe and comfortable in the elements. Also developing relationships with the locals, the Sherpas and the other Nepalese persons who are supporting the expedition.

SN: What do you want people to take away from your Full Circle Everest expedition?

Mullins: Diversity in the outdoors matters. The military completely introduced me to outdoor sports. When I was a kid, I never went camping or even hiking. I thought [Brooklyn’s] Prospect Park was the wilderness. These activities have benefits for all people. Hopefully, Full Circle will help African Americans of all ages get outside to hike, camp and explore.

Some mosquito-borne viruses turn mice into alluring mosquito bait.

Mice infected with dengue or Zika viruses — and people infected with dengue — emit a flowery, orange-smelling chemical that tempts hungry mosquitoes, researchers report June 30 in Cell. In mice, the infections spur the growth of skin-inhabiting bacteria that make the chemical, drawing in bloodsucking Aedes aegypti mosquitoes that could then transmit the viruses to new hosts, including humans.

Previous studies showed that other mosquito species prefer to feed on animals carrying the parasite that causes malaria (SN: 2/9/17). But it was unknown whether the same was true for viruses such as dengue or Zika, says Gong Cheng, a microbiologist at Tsinghua University in Beijing.

The chemical acetophenone — which to humans smells like orange blossom — may be that lure. Mice infected with dengue or Zika viruses give off approximately 10 times more acetophenone and attract more mosquitoes than uninfected animals, Cheng and colleagues found. People infected with dengue similarly release more of the chemical than healthy people. Samples of odors taken from the armpits of infected people also created potent mosquito magnets when smeared on filter paper attached to a volunteer’s palm.
Acetophenone typically comes from bacteria. Researchers found that Bacillus bacteria on mice were the likely culprits producing the chemical. An infection stops mice from making an antimicrobial protein called RELMα, allowing the acetophenone-emitting microbes to flourish.

But a component of some acne medications can bring back RELMα in mice, the team found. Infected animals fed a derivative of vitamin A called isotretinoin produced less acetophenone and become less attractive mosquito targets.

It’s possible that giving people isotretinoin could help reduce virus transmission among people by hiding infected people from the bloodsucking insects, Cheng says. He and colleagues are planning to test the strategy in Malaysia, where dengue circulates.