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Highlights from Duke in Australia

Duke in Australia 2023 in front of 1.9-billion-year-old stone in the Northern Territory. Photo by one of our tour guides.

Australia. For years it was more of a nebulous concept to me than a concrete place. It was a colorful patch on maps, home to animals I’d read about but never seen. Now it’s a place where I’ve run my hands over 1.9-billion-year-old stone, watched a platypus emerge from a river at dawn, gotten bitten on the tongue by an ant with a tasty green butt (long story), and spent a thousand other moments with wonderful people in places I hope to never forget.

That’s all thanks to Duke in Australia, a month-long biogeography course led by Alex Glass, Ph.D., and Nancy Lauer, Ph.D., that delves into Australian flora, fauna, geology, history, and culture. When people ask about my experience there this summer, I have a hard time answering. “Wonderful” doesn’t begin to cover it. The experience still doesn’t feel entirely real to me. Even when I was in Australia, watching a platypus or a parrot or standing on a beach with a sunrise on one side and a rainbow on the other, I sometimes couldn’t entirely believe where I was.

Sunrise at Myall Beach on Cape Tribulation, where the Daintree Rainforest meets the Great Barrier Reef.

Disclaimer: When I say “Highlights from Duke in Australia,” I’m referring to my own personal highlights—some of which, let me assure you, were not universally popular with my classmates. Like the enormous crickets we saw on our rainforest night hike, or the time I found the shed skin of a huntsman spider and went around showing it to everyone nearby, or the delightfully squelchy mud coating the trail on one of our last hikes. For more detailed accounts of our day-to-day activities, check out the student blogs on the Duke in Australia 2023 website.

From the moment we landed in Sydney, I was keeping my eyes peeled for bird sightings. (I am slightly into birds. Just slightly.) Unless you count an ambiguous white flash seen through a bus window, my first bird sighting in Australia was a small group of rainbow lorikeets flying over the city. With a blue head and stomach, a green back, an orange-red breast, and flashes of yellow under the wings, the species is very well named.

Lorikeets weren’t the only birds we saw in Sydney. Common mynas, which always looked vaguely sinister to me, watched us while we ate dinner the first night. Pigeons strutted along the sidewalks—the only bird species I saw in Australia that I’d also seen in the US, except a possible peregrine falcon that I caught only a brief glimpse of during a hike. There were also Australian ibises all over the city, colloquially known as bin chickens for their dumpster-diving habits. Personally, I thought the ibises were lovely, regal birds.

There are other birds, however, that can no longer call Sydney home. One of my favorite sites in Sydney was the Forgotten Songs art installation at Angel Place. It is a short alley engraved with the names of fifty bird species that can no longer survive in the city. Empty bird cages hang suspended above the street. Our tour guide told us that the exhibit normally plays recordings of the birds, but that part was under renovation, so it was playing music instead. A few days later, I returned to the exhibit on my own so I’d have time to read every bird name. Those empty cages still haunt me.

An eleven-armed seastar in one of the tide pools at Bondi Beach. (Eleven-armed seastars do not always have eleven arms.) Below it, you can see Neptune’s necklace, a type of algae resembling strings of beads.

On our first full day in Sydney, we went to Bondi Beach to explore the tidepools. There were crabs and octopi, seastars and anemones, necklace-like algae and tiny blue snails called little blue periwinkles. That afternoon, we sat on the beach and learned about microplastics from Lauer. (Not-so-fun fact: we eat a credit card’s worth of microplastics every week on average.) Some of us lingered on the beach afterward and went swimming. The water was frigid, but it was there, with cold water and sand swirling around me in a part of the ocean I’d never seen, much less swum in, that the reality of being on a new continent completely hit me.

Sunshine wattle flowers on our hike at North Head, viewed through a hand lens.

Our first group hike was overwhelming, almost dizzying. Outside of urban Sydney, it was easier for me to recognize just how different Australia was from the US, and it was impossible to absorb everything at once. In every direction were unfamiliar plants and landscapes. Norfolk pine, coastal rosemary, mountain devil, sunshine wattle, Darwinia, flannel flower, gray spider flower…. I was especially entranced by casuarina, which looks shockingly like a pine tree but is actually a flowering plant that has evolved conifer-like traits to preserve water. We were in a heath, characterized by low-growing plants adapted to dry, nutrient-poor conditions. Nothing about it looked like the woods and fields and mountains back home.

Our focus that day was studying plants, but I was having a hard time focusing on any one thing for more than about a second. At one point, we were supposed to be observing a beautiful plant to my right, but half the group had already moved on to another species farther up the trail, and meanwhile, a bird I had certainly never seen in my life was perched remarkably cooperatively on a bush off to the left. There are too many things happening, I remember thinking. I was juggling my field notebook, hand lens, phone camera, and binoculars, and I didn’t even know where to look. I chose to stare at the bird, following the logic that it could fly away at any moment, whereas the plants would stay exactly where they were. That brilliant plan turned out to be faulty. The plants might stay still, but we wouldn’t—so much to see, so little time.

A galah, a species of cockatoo, in Katoomba.

Our next stop was Katoomba, a small mountain town in New South Wales.  It was a quiet, peaceful place, vastly different from Sydney. When I think of Katoomba, I think of the sulfur-crested cockatoo perched on a bakery sign just feet away from me and the flock of strikingly pink cockatoos called galahs in a local park. I think of the superb lyrebird that crossed our path directly in front of us and the rare Wollemi pine growing beside a road.

We took a hike at Wentworth Falls, where Darwin himself once walked. It’s part of the Great Dividing Range, but we learned that the mountains are actually “incised terrain,” formed when valleys were cut into a plateau, leaving “mountains” behind. We also drove to the Jenolan Caves and explored cavernous underground spaces bursting with crystal formations like stalactites, flowstone, and hollow soda straws. These lovely, fragile cave structures, or speleothems, are formed by the gradual deposition of dissolved minerals as water drips through a cave. Before we left, we saw an underground river with water so clear that I didn’t immediately realize I was looking at water at all.

Part of the Jenolan Caves. Gradual geologic processes form decorative structures, or speleothems, in caves.

Another day in Katoomba, our group took a gorgeous hike through a eucalypt forest. Literally everywhere I looked in that forest, there was something extraordinary. Ancient tree ferns. Ruby-red sap seeping out of a tree trunk. The Three Sisters rock formation framed by the aptly named Blue Mountains. Towering eucalypt and turpentine trees. At the end of the hike, we rode the Scenic Railway, the steepest in the world. It was terrifying—awesome, but terrifying.

A view from one of our hikes in the Blue Mountains.

Next, we flew to the Northern Territory, where we checked into our hostel in Darwin. We were now in crocodile country, home to the world’s largest reptile: the saltwater or estuarine crocodile. We were instructed to avoid going in any body of water, saltwater or otherwise, unless it was specifically designated as safe for swimming. (The name “saltwater crocodile” is misleading—the crocodiles can inhabit fresh water as well, and they are extremely aggressive and dangerous.) It was very important to be crocwise.

A rainbow bee-eater at the George Brown Darwin Botanic Gardens in Darwin, a city in the Northern Territory.

The first few days in Darwin, we didn’t see any crocodiles, but there were birds seemingly everywhere. Varied triller, which I originally misidentified as the buff-sided robin until a local eBird reviewer emailed me and asked me to correct my eBird report. Rainbow bee-eater, remarkably common for a bird that looks too beautiful to be real. Peaceful dove. Blue-faced honeyeater. Australasian figbird.

We took a hike that went through a beautiful mangrove, where we learned that the term mangrove isn’t specific to any particular type of plant; it’s used to refer to many very different species that have all adapted to the same challenges, including salinity, changing tides, and nutrient-poor soil. There were crabs and snails and birds—so many birds, some of which I still haven’t identified, like the group of black, crested birds with bright red inside their beaks.

Green weaver ants. Note their distinctive green abdomens, which contain ascorbic acid and have an interesting taste.

When we emerged from the mangrove, we came across a nest of green weaver ants. Their bright green abdomens are rich in ascorbic acid, and the ants have traditionally been used for purposes ranging from treating colds to making a sort of “lemonade” to stimulating milk production. Many of us were eager to taste the ants, though Glass warned us that they “bite vigorously.” Some of my classmates carefully held an ant with their fingers while giving the abdomen a quick lick. I, on the other hand, decided to let an ant crawl onto my notebook while I licked it so it couldn’t bite my fingers. Clever, right? Well, it worked—the ant didn’t bite my fingers. It bit my tongue instead. “Vigorously.” Its mouthparts remained latched on even as I was spitting out ant parts onto the ground. I can’t blame it—I’d be upset, too, if a giant tried to lick me.

Before long, it was time for the jumping crocodile tour. We boarded a tour boat and floated down a seemingly peaceful river while our guide dangled hunks of meat from big fishing rods to bait the crocodiles to leap several feet out of the water and snap their jaws around the food. Their bite force, incidentally, is the highest of any living animal, up to 3700 pounds per square inch. Jumping is natural for the crocodiles—they hunt that way to snag animals like birds and wallabies that venture too close to the water. Being that close to enormous predators roused some deep, primeval fear in me. To a crocodile, I would make excellent prey. The jumping crocodile tour, needless to say, was very memorable. Our class later had a long and far-ranging discussion on the many types of ecotourism experiences we’d participated in and their costs, benefits, and ethical implications.

One of the crocodiles on the jumping crocodile tour.

The next day, we left for a three-day camping trip in Kakadu and Litchfield National Parks. It was the dry season, and the weather was hot, dry, and sunny. We went hiking and snorkeling (in croc-free swimming holes), saw the breathtaking magnetic and cathedral termite mounds, and learned about geology and Aboriginal cultures. Some of the places we visited were sacred sites of the people who have inhabited the region for more than 65,000 years. One of the rock art paintings we were able to see was of a Tasmanian tiger, an animal that’s been completely extinct for close to a century and extinct in the Kakadu region for thousands of years. But right there on the wall was the preserved memory of a time when Tasmanian tigers still roamed the area.

Me with a stick insect at our campground in Kakadu National Park in Australia’s Northern Territory. Photo by Letar Jia, another student in the Duke in Australia program this summer.

One of the coolest places we stopped was a rock cut-out along a highway. The stone was striped with zigzagging layers created when it was buried underground at a pressure high enough to fold solid rock. It was formed 1.9 billion years ago, when the earth was “a geologist’s dream,” according to Glass–relatively barren, with no soil, plants, or animals, just microscopic organisms and lots and lots of rock. I was touching 1.9 billion years of history.

We spent the third night at a different campsite. Some of us spotted what seemed to be a large spider in the bathroom, but one of the tour guides informed me that it was actually just the shed skin of a huntsman spider, not the spider itself. I walked around camp introducing people to my “little friend,” but oddly enough, they didn’t seem as delighted as I was.

That night, while we were theoretically sleeping, periodic cacophonies of eerie, wailing screams reverberated through the air. My half-asleep brain was convinced they were from wallabies, but the sound actually came from a bird called the bush stone-curlew or bush thick-knee. The next morning, there was a gecko in the bathroom, and I wasn’t sure my day could possibly get any better. But later that day, we visited a fragment of an ancient rainforest, and there were giant fruit bats practically dripping from the canopy and giant golden orb weaver spider webs strung between trees, and I think that was even better than the bathroom gecko.

A female giant golden orb weaver, with my hand for scale. The tiny, orange spider on her back is the male.

After departing Darwin, we headed to Cape Tribulation, where the Great Barrier Reef meets the Daintree Rainforest—believed to be the oldest rainforest on the planet. Some rainforests, Glass explained, exist because they’re near the equator. But the rainforests in Australia are remnants of ancient rainforests that developed when the continents were arranged very differently and Australia was considerably farther south. Australia’s climate has become more arid over time, but pockets of its ancient rainforests remain intact.

While we were on Cape Tribulation, we had the chance to snorkel on the Great Barrier Reef. It was overcast and very windy that day, and the small boat that took us out to the reef turned into a rollercoaster as it slid up and down waves. But windy or not, the reef was gorgeous. We saw sea turtles, a sea cucumber, a small shark, and fishes and corals in endless colors.

We also had the incredible opportunity to hike through the rainforest at night. Of all the amazing things we did, that may have been my favorite. There were huge crickets and spiders, thorny vines called wait-a-whiles (because you’ll be waiting a while if you get stuck on one), and flowering plants that looked like mushrooms. And partway along the boardwalk, Glass spotted a creature so unusual and elusive that he had never seen one before. This, he told us, was probably the rarest animal we’d seen on the whole trip. A velvet worm. It looked a bit like a caterpillar or a centipede at first glance, but velvet worms have an entire phylum all their own. (Caterpillars and centipedes share the Arthropoda phylum, along with all insects, spiders, crustaceans, and various others. Velvet worms are in the Onychophora phylum.) The ancestors of velvet worms are thought to represent a link between arthropods and segmented worms. They are ancient, unique, and rarely seen.

The velvet worm.

Just moments later, Glass announced another incredible find: a peppermint stick. I raced ahead to see it. Earlier that day, I’d seen signs about peppermint stick insects, which excrete a peppermint-scented liquid as a defense mechanism, and I’d been keeping my eyes peeled ever since. The creature had developed a sort of mythical status in my mind; I’d been fantasizing about seeing one but hadn’t actually expected to. But there it was, right in front of us, large and stick-like, its color a blue-green so bright that it almost seemed to glow.

A platypus in a river in Yungaburra.

In Yungaburra, our next-to-last stop, we saw enormous fig trees and gorgeous waterfalls. On our last morning, several of us left the motel around dawn and walked to a nearby trail along a river in search of the platypus and the tree kangaroo, an arboreal kangaroo species. We found both. It was a fitting almost-ending to our trip. Both platypuses and kangaroos seem so iconically Australian. The platypuses slipped in and out of the water, their dark bodies visible even in the low light. The tree kangaroo watched us silently from its perch above us and then slowly began to move elsewhere.

A tree kangaroo in Yungaburra.

Before long, it was time to go home. We spent a couple days in Cairns first, where I saw a shiny, emerald green beetle and a tree positively full of squawking lorikeets. Even in the city, there were bright and beautiful animals. In places like the ones we visited, it is easy to find awe and wonder and beauty everywhere you look. But there are endless treasures here, too, fascinating and beautiful sights that we walk past every day, like the way spiderwebs turn silver in the sunlight, or the gray catbird that eats bright red magnolia fruits in the courtyard in front of my dorm window, or the tiny, bluish purple flowers on the Al Buehler Trail, soft and fuzzy and damp when I brushed my face against them. Duke in Australia was an unforgettable adventure. It was also a reminder to step out of the human bubble and immerse myself in the worlds of other living things—whether here or across the globe.

Post by Sophie Cox, Class of 2025

Helping People and Wildlife Coexist in Ways That Benefit Both, Using Math

Duke team wins top prize in mathematical modeling contest


Safari-goers watch a pride of lions in the Maasai Mara, a famous game reserve in Kenya. Credit: Ray in Manila, CC BY 2.0 via Wikimedia Commons
Safari-goers watch a pride of lions in the Maasai Mara, a famous game reserve in Kenya. Credit: Ray in Manila, CC BY 2.0 via Wikimedia Commons

Of all the math competitions for college students, the annual Mathematical Contest in Modeling (MCM) is one of the biggest. And this year, Duke’s team took home a coveted top prize.

Undergraduates Erik Novak, ’24, Nicolas Salazar, ’23, and Enzo Moraes Mescall, ’24, represented the Blue Devils at this year’s contest, a grueling 4-day event where teams of undergraduates use their mathematical modeling skills to solve a real-world problem. The results are finally in, and the Duke team was chosen as one of the top 22 outstanding winners out of more than 11,200 teams worldwide.

Their task: to analyze some of the challenges facing a nature reserve in Kenya known as the Maasai Mara. This region is named for the local Maasai people, a tribe of semi-nomadic people who make a living by herding cattle. It’s also teeming with wildlife. Each year, more than a million wildebeests, zebras and gazelles travel in a loop from neighboring Tanzania into Kenya’s Maasai Mara Reserve and back, following the seasonal rains in search of fresh grass to eat.

Some 300,000 safari-goers also flock to the area to witness the massive migration, making it a major player in Kenya’s billion-dollar tourism industry. But protecting and managing the land for the benefit of both wildlife and people is a delicate balancing act.

The reserve relies on tourism revenue to protect the animals that live there. If tourism slumps — due to political unrest in Kenya, or the COVID-19 pandemic — desperate communities living around the park resort to poaching to get by, threatening the very wildlife that tourism depends on.

Poachers aren’t the only problem: wild animals such as lions, leopards and elephants sometimes venture into human settlements in search of food. Conservationists must strike a balance between protecting these animals and managing the dangers they pose by raiding crops or killing valuable domestic livestock.

Tourism is a mixed blessing, too. While safari-goers bring money into the region, they can also disturb the animals and pollute the Mara River, and off-road drivers can erode the soil with their jeeps.

The mission facing the Duke team was to identify ways to mitigate such conflicts between wildlife and people.

From left: Teammates Erik Novak, ’24, Nicolas Salazar, ’23, and Enzo Moraes Mescall ’24 finished in the top 0.1% in the 2023 Mathematical Contest in Modeling.

This year’s contest ran over a single weekend in February. Camped out on the third floor of Perkins library, the team of three worked 12 hours a day, fueled by a steady supply of Red Bull and poke bowls. During that time, they built a model, came up with budget and policy recommendations, and wrote a 25-page report for the Kenyan Tourism and Wildlife Committee, all in less than 96 hours.

They built a mathematical model consisting of a system of six ordinary differential equations. According to the model’s predictions, they said, it should theoretically be possible to increase the reserve’s animal populations by about 25%, reduce environmental degradation by 20%, nearly eliminate retaliatory lion killings, and cut poaching rates in half — all while increasing the average yearly flow of tourists by 7.5%.

Participating in a smaller-but-similar contest last fall, the Triangle Competition in Mathematical Modeling, helped them prepare. “It’s kind of like a practice for the MCM,” Salazar said.

Veronica Ciocanel

“They did not win that contest, but they took everything they learned and look what they did with it. I’m very proud,” said assistant professor of mathematics and biology Veronica Ciocanel, who coached the team and co-organized the Triangle competition.

In addition to finishing in the top 0.1% of competitors, the Duke team got three additional awards for their performance; the Mathematical Association of America (MAA) award, the Society for Industrial and Applied Mathematics (SIAM) prize, and an International COMAP Scholarship Award of $10,000.

The problems in these contests tend to be much more open-ended than typical coursework. “We didn’t know what the solution was supposed to be or what tools to use,” Novak said.

Modeling, computation and coding skills are certainly important, Ciocanel said. “But really what matters more is practice, teamwork, and communicating their results in a written report. Students who have a solid course background don’t need to do anything else to prepare, they just need to be creative about using what they know from the courses they already took.”

“Use what you have and work well together,” Ciocanel said. “That I think is the most important thing.”

Robin Smith
By Robin Smith

Neuroscience Shows Why Sex Assault Victims “Freeze.” It’s Not Consent.

Warning: the following article discusses rape and sexual assault. If you or someone you know has been sexually assaulted, help is available.

Image: DreamStudio AI, with prompt “Woman, screaming, sitting on the witness stand in a U.S. court of law, in the style of Edvard Munch’s ‘The Scream’”

“You never screamed for help?”

“Why didn’t you fight back?”

These are questions that lawyers asked E. Jean Carroll in her rape case against former president Donald J. Trump this spring. These kinds of questions reflect a myth about rape: that it’s only rape if the victim puts up a fight.

A recent review of the research, “Neuroscience Evidence Counters a Rape Myth,” aims to set the record straight. It serves as a call to action for those in the scientific and legal professions. Ebani Dhawan completed this work at the University College London with Professor Patrick Haggard. She is now my classmate at Duke University, where she is pursuing an MA in Bioethics & Science Policy.

Ebani Dhawan

Commonly accepted beliefs and myths about rape are a persistent problem in defining and prosecuting sexual assault. The intentions of all actors are examined in the courtroom. If a victim freezes or does not attempt to resist during a sexual assault, perpetrators may claim there was passive acquiescence; that consent was assumed from an absence of resistance.

From the moment a victim reports an assault, the legal process poses “why” questions about the survivor’s behavior. This is problematic because it upholds the idea that survivors can (and should) choose to scream or fight back during an assault.

This new paper presents neuroscientific evidence which counters that misconception. Many survivors of sexual assault report ‘freezing’ during an assault. The researchers argue that this is an involuntary response to a threat which can prevent a victim from actively resisting, and that it occurs throughout biology.

Animal studies have demonstrated that severe, urgent threats, like assault or physical restraint, can trigger a freeze response involving fixed posture (tonic immobility) or loss of muscle tone (collapsed immobility). Self-reports of these states in humans shed light on an important insight into immobility. Namely, that we are unable to make voluntary actions during this freezing response.

An example of this is the “lockup” state displayed by pilots during an aviation emergency. After a plane crash, it’s hard to imagine anyone asking a pilot if they froze because they really wanted to crash the plane.

Yet, quite frequently victims of sexual assault are asked to explain the freeze response, something which is further made difficult by the impaired memory and loss of sense of agency which often accompanies trauma.

The legal process around sexual assault should be updated to reflect this neuroscientific evidence.

THIS MYTH HAS REAL CONSEQUENCES.

The vast majority of sexual assault cases do not result in a conviction. It is estimated that out of every 1,000 sexual assaults in the U.S., only 310 are reported to the police and only 28 lead to felony conviction. That is a conviction rate of less than 3%.

In England and Wales, just 3% of rapes recorded in the previous year resulted in charges. According to RAINN, one of the leading anti-sexual assault organizations, many victims don’t report because they believe the justice system would not do anything to help — a belief that these conviction rates support.

E. Jean Carroll named this in her trial. She said, “Women don’t come forward. One of the reasons they don’t come forward is because they’re always asked, why didn’t you scream? You better have a good excuse if you didn’t scream.”

This research serves as a much-needed call-to-action. By revisiting processes steeped in myth, justice can be better served.

I asked Ebani what she thinks must be done. Here are her recommendations:

  1. The neuroscience community should pursue greater mechanistic understanding of threat processing and involuntary action processes and the interaction between them. 
  2. Activists and legal scholars should advocate for processes reflective of the science behind involuntary responses like freezing, and the inability of victims to explain that behavior.
  3. Neuroscientists should contribute to Police officers’ education regarding involuntary responses to rape and sexual assault.

“I’m telling you: He raped me whether I screamed or not.” – E. Jean Carroll

Post by Victoria Wilson, Class of 2023

New Rankings Place Duke Scholars on Top of the World

L-R: Tomasello, Moffitt, Caspi, Lefkowitz.

We didn’t know we needed another way to rank the importance of Duke’s scientists, but the folks at research.com have gone ahead and developed one anyway. And in its second year of data, several Duke people come out in the top ten nationally and globally. So, okay, maybe we did need a new ranking system!

Duke Psychology and Neuroscience swept the U.S. medals in psychology: Terrie E. Moffitt Ph.D., first, Michael Tomasello, Ph.D. second, and Avshalom Caspi, Ph.D. third. Duke University’s psychology is overall ninth in the world, according to this ranking.

Moffitt, the Nannerl O. Keohane University Distinguished Professor of P&N, and Caspi, the Edward M. Arnett Distinguished Professor of P&N, are frequent co-authors on a lifelong psychology and health study of 1,000 people born in Dunedin, New Zealand. Moffitt ranks fourth in the world in psychology, with 207,903 citations of her 582 works. Caspi’s 159,598 citations of 507 papers were good enough for 10th in the world.

Developmental psychologist Tomasello, the James F. Bonk Distinguished Professor of P&N, has focused his work on cognitive development, social cognition and language acquisition. He has 147,951 citations on an even 800 works, placing him second in the U.S. and ninth in the world.

Nobel laureate Robert Lefkowitz M.D., the chancellor’s distinguished professor of medicine, is ranked second in the nation and third in the world for Biology and Biochemistry with 198,000 citations of his 881 papers. The rankings reflect the importance of Lefkowitz’s discovery and characterization of the 7-transmembrane g-coupled protein receptor (GPCR), a fundamental signaling port on the surface of cells that is targeted by a third to a half of all prescription drugs.

Koenig

Psychiatry and Behavioral Sciences professor and Co-Director of Duke’s Center for Spirituality, Theology and Health, Harold G. Koenig M.D., was ranked seventh in the nation and 10th in the world for Social Sciences and Humanities for his work on spirituality and health. His 703 publications have earned 66,404 citations.

Many other Duke scholars finished in the top 100 worldwide in their respective fields, some even making a mark in multiple fields. Check it out.

Methodology: Research.com’s ranking of the best scholars by discipline relies on data consolidated from various sources including OpenAlex and CrossRef. The bibliometric data for estimating the citation-based metrics were collected on Dec. 21, 2022. Position in the ranking is based on a researcher’s D-index (Discipline H-index), which includes exclusively papers and citation metrics for an examined discipline.

And just to prevent some letters to the editor, we acknowledge that the H-index has its critics, including its inventor. We don’t make the rankings folks, we just share them.

Shifting from Social Comparison to “Social Savoring” Seems to Help

The face of a brown-eyed girl with freckles, bangs and new adult teeth fills most of the frame. Superimposed to the right are the icons of multiple real and imagined social media apps in a semicircular arrangement. Image by geralt, via Pixabay.
Image by geralt, via pixabay.

The literature is clear: there is a dark side to engaging with social media, with linkages to depressive symptoms, a sense of social isolation, and dampened self-esteem recently revealed in the global discourse as alarming potential harms.

Underlying the pitfalls of social media usage is social comparison—the process of evaluating oneself relative to another person—to the extent that those who engage in more social comparison are at a significantly higher risk of negative health outcomes linked to their social media consumption.

Today, 72 percent of Americans use some type of social media, with most engaging daily with at least one platform.(1) Particularly for adolescents and young adults, interactions on social media are an integral part of building and maintaining social networks.(2-5) While the potential risks to psychosocial well-being posed by chronic engagement with these platforms have increasingly come to light within the past several years, mitigating these adverse downstream effects poses a novel and ongoing challenge to researchers and healthcare professionals alike.

The intervention aimed to supplant college students’ habitual social comparison … with social savoring: experiencing joyful emotions about someone else’s experiences.

A team of researchers led by Nancy Zucker, PhD, professor in Psychiatry & Behavioral Sciences and director of graduate studies in psychology and neuroscience at Duke University, recently investigated this issue and found promising results for a brief online intervention targeted at altering young adults’ manner of engagement with social media. The intervention aimed to supplant college students’ habitual social comparison when active on social media with social savoring: experiencing joyful emotions about someone else’s experiences.

A cartoon depicts a small man in a ball cap standing on a table with a smartphone nearby. A larger person on the right with a cat-like nose regards him with tears in her eyes.
Image from Andrade et al

Zucker’s team followed a final cohort of 55 college students (78 percent female, 42 percent White, with an average age of 19.29) over a two-week period, first taking baseline measures of their mental well-being, connectedness, and social media usage before the students returned to daily social media usage. On day 8, a randomized group of students received the experimental intervention: an instructional video on the skill of social savoring. These students were then told to implement this new skill when active on social media throughout days 8 to 14, before being evaluated with the rest of the cohort at the two-week mark.

For those taught how and why to socially savor their daily social media intake, shifting focus from social comparison to social savoring measurably increased their performance self-esteem—their positive evaluation—as compared with the control group, who received no instructional video. Consciously practicing social savoring even seemed to enable students to toggle their self-esteem levels up or down: those in the intervention group reported significantly higher levels of self-esteem on days during which they engaged in more social savoring.

Encouragingly, the students who received the educational intervention on social media engagement also opted to practice more social savoring over time, suggesting they found this mode of digesting their daily social media feeds to be enduringly preferable to that of social comparison. The team’s initial findings suggest a promising future for targeted educational interventions as an effective way to improve facets of young adults’ mental health without changing the quantity or quality of their media consumption.

Of course, the radical alternative—forgoing social media platforms altogether in the name of improved well-being—looms in the distance as an appealing yet often unrealistic option for many; therefore, thoughtfully designed, evidence-based interventions such as this research team’s program seem to offer a more realistic path forward.

Read the full journal article.

References

  1. Auxier B, Anderson M. Social media use in 2021: A majority of Americans say they use YouTube and Facebook, while use of Instagram, Snapchat and TikTok is especially common among adults under 30. 2021.
    2. McKenna KYA, Green AS, Gleason MEJ. Relationship formation on the Internet: What’s the big attraction? J Soc Issues. 2002;58(1):9-31.
    3.Blais JJ, Craig WM, Pepler D, Connolly J. Adolescents online: The importance of Internet activity choices to salient relationships. J Youth Adolesc. 2008;37(5):522-536.
    4. Valkenburg PM, Peter J. Preadolescents’ and adolescents’ online communication and their closeness to friends. Dev Psychol. 2007;43(2):267-277.
    5. Michikyan M, Subrahmanyam K. Social networking sites: Implications for youth. In: Encyclopedia of Cyber Behavior, Vols. I – III. Information Science Reference/IGI Global; 2012:132-147.

Guest Post by Eleanor Robb, Class of 2023

What does it take to be a successful PhD student? Two grad students in statistics weigh in

With so many different career options in life, how do you know that you’ve found the right one for you?

Graduate students Edric Tam and Andrew McCormack, when asked what they hope to be doing in ten years, said they’d choose to do exactly the kind of work they’re doing right now – so clearly, they’ve found the right path. Tam, who obtained his undergraduate degree in Biomedical Engineering, Neuroscience and Applied Mathematics from Johns Hopkins University, and McCormack, who came from the University of Toronto with a degree in Statistics, are now 5th-year PhD students in the Department of Statistical Sciences. Tam works with Professor David Dunson, while McCormack works with Professor Peter Hoff, and both hope to pursue research careers in statistics.

Edric Tam
Andrew McCormack

Research interests

For the past five years, McCormack has been doing more theoretical research, looking at how geometry can lend insights into statistical models. The example he gives is of the Fisher information matrix, a statistical model that many undergraduate statistics majors learn in their third or fourth year.

Tam, meanwhile, looks at data with unique graphical and connectivity structures that aren’t quite linear or easily modeled, such as a brain connectome or a social network. In doing so, he works on answering two questions – how can you model data like this, and how can you leverage the unique structure of the data in the process?

What both Tam and McCormack like about the field of statistics is that, as Tam puts it, “you get to play in everyone’s backyard.” Moreover, as McCormack says, the beauty of theoretical research is that, while it’s certainly more time-consuming and incremental, it is often timeless, giving insight into something previously unknown.

On walking the research path

What does it take to be a successful PhD student? Both McCormack and Tam agree that a PhD is just a degree – anyone can get one if you work hard. But what sustains both through a career in research is a passion for what they do. Tam says that “you need inherent motivation, curiosity, passion, and drive.” McCormack adds that it helps if you work on problems that are interesting to you. 

Tam, who spent some time in a biomedical engineering lab during his undergraduate years, remembers reading about math and statistics the entire time he was there, which signaled to him that maybe, biomedical engineering wasn’t for him. McCormack’s defining moment occurred in the proof-based classes he took while as an undergraduate. He initially wanted to pursue a career in finance, but he quickly became enamored by the elegant precision of mathematical proofs – “even if all you’re proving is that 1+1=2!”

“You need inherent motivation, curiosity, passion, and drive.”

Edric tam, on what it takes to pursue a career in research

Even with passion for what you do, however, research can have its ups and downs. McCormack describes the rollercoaster of coming up with a new idea, convinced that “this is a paper right here”, and then a day later, after he’s had time to think about the idea, realizing that it isn’t quite up to the mark. Tam, who considers himself a pretty laidback person, sometimes finds the Type A personalities in research, as in any career field, too intense. Both McCormack and Tam prefer to not take themselves too seriously, and both exude a love for – and a trust of – the process.

Tam, not taking himself too seriously

Reflections on the past and the future

Upon graduation, McCormack will move to Germany to pursue a post-doc before beginning a job as Assistant Professor in Statistics at the University of Alberta. Tam will continue his research at Duke before applying to post-doc programs. In reflecting on their paths that have brought them till now, both feel content with the journey they’ve taken.

Tam sees the future in front of him – from PhD to post-doc to professorship – as “just a change in the title, with more responsibility”, and is excited to embark on his post-doc, where he gets to continue to do the research he loves. “It doesn’t get much better than this,” he laughs, and McCormack agrees. When McCormack joins the faculty at the University of Alberta, he’s looking forward to mentoring students in a much larger capacity, although he comments that the job will probably be challenging and he’s expecting to feel a little bit of imposter syndrome as he settles in.

When asked for parting thoughts, both Tam and McCormack emphasize that the best time to get into statistics and machine learning is right now. The advent of ChatGPT, for example, could replace jobs and transform education. But given their love for the field, this recommendation isn’t surprising. As Tam succinctly puts it, “given a choice between doing math and going out with friends, I would do math –  unless that friend is Andy!”

Post by Meghna Datta, Class of 2023

When Art and Science Meet as Equals

Artists and scientists in today’s world often exist in their own disciplinary silos. But the Laboratory Art in Practice Bass Connections team hopes to rewrite this narrative, by engaging Duke students from a range of disciplines in a 2-semester series of courses designed to join “the artist studio, the humanities seminar room, and the science lab bench.” Their work culminated in “re:process” – an exhibition of student artwork on Friday, April 28, in the lobby of the French Family Science Center. Rather than science simply engaging artistic practice for the sake of science, or vice versa, the purpose of these projects was to offer an alternate reality where “art and science meet as equals.”

The re:process exhibition

Liuren Yin, a junior double-majoring in Computer Science and Visual and Media Studies, developed an art project to focus on the experience of prosopagnosia, or face blindness. Individuals with this condition are unable to tell two distinct faces apart, including their own, often relying on body language, clothing, and the sound of a person’s voice to determine the identity of a person. Using her experience in computer science, she developed an algorithm that inputs distinct faces and outputs the way that these faces are perceived by someone who has prosopagnosia.

Yin’s project exploring prosopagnosia

Next to the computer and screen flashing between indistinguishable faces, she’s propped up a mirror for passers-by to look at themselves and contemplate the questions that inspired her to create this piece. Yin says that as she learned about prosopagnosia, where every face looks the same, she found herself wondering, “how am I different from a person that looks like me?” Interrogating the link between our physical appearance and our identity is at the root of Yin’s piece. Especially in an era where much of our identity exists online and appearance can be curated any way one wants, Yin considers this artistic piece especially timely. She writes in her program note that “my exposure to technologies such as artificial intelligence, generative algorithms, and augmented reality makes me think about the combination and conflict between human identity and these futuristic concepts.”

Eliza Henne, a junior majoring in Art History with a concentration in Museum Theory and Practice, focused more on the biological world in her project, which used a lavender plant in different forms to ask questions like “what is truthful, and what do we consider real?” By displaying a live plant, an illustration of a plant, and pressings from a plant, she invites viewers to consider how every rendition of a commonly used model organism in scientific experiments omits some information about the reality of the organism.

Junior Eliza Henne

For example, lavender pressings have materiality, but there’s no scent or dimension to the plant. A detailed illustration is able to capture even the way light illuminates the thin veins of the leaf, but is merely an illustration of a live being. The plant itself, which is conventionally real, can only further be seen in this sort of illustrative detail under a microscope or in a diagram.

In walking through the lobby of FFSC, where these projects and more are displayed, you’re surrounded by conventionally scientific materials, like circuit boards, wires, and petri dishes, which, in an unusual turn of events are being used for seemingly unscientific endeavors. These endeavors – illustrating the range of human emotion, showcasing behavioral patterns like overconsumption, or demonstrating the imperfection inherent to life – might at first glance feel more appropriate in an art museum or a performing arts stage.

But the students and faculty involved in this exhibition see that as the point. Maybe it isn’t so unnatural to build a bridge between the arts and the sciences – maybe, they are simply two sides of the same coin.

Post by Meghna Datta, Class of 2023

Meet Some of the Teams at the Bass Connections Showcase

If you weren’t outside enjoying the sun on Wednesday, April 19, you were probably milling around Penn Pavilion, a can of LaCroix in hand, taking in the buzz and excited chatter of students presenting at the 2023 Fortin Foundation Bass Connections Showcase.

Open floor presentations at the 2023 Bass Connections Showcase

This annual celebration of Bass Connections research projects featured more than 40 interdisciplinary teams made up of Duke faculty, graduate students, undergraduate students, and even partners from other research institutions.

Research teams presented posters and lightning talks on their findings. You might have heard from students aiming to increase representation of women in philosophy; or perhaps you chatted with teams researching physiotherapy in Uganda or building earthquake warning systems in Nepal. Below, meet three such teams representing a wide variety of academic disciplines at Duke.

Building sustainable university-community partnerships

As Bass Connections team member Joey Rauch described, “this is a poster about all of these other posters.” Rauch, who was presenting on behalf of his team, Equitable University-Community Research Partnerships, is a senior double-majoring in Public Policy and Dance. His interest in non-profit work led him to get involved in the team’s research, which aims to offer a framework for ethical and effective university-community research collaboration – exactly what teams do in Bass Connections. The group looked at complicated factors that can make equitable relationships difficult, such as university incentive structures, power dynamics along racial, socioeconomic, and ethnic lines, and rigid research processes.

Senior Joey Rauch with his team’s 2nd-place poster!

Along the lines of rigid research, when asked about what his favorite part of Bass Connections has been, Rauch remarked that “research is oddly formal, so having a guiding hand through it” was helpful. Bass Connections offers an instructive, inclusive way for people to get involved in research, whether for the first or fourth time. He also said that working with so many people from a variety of departments of Duke gave him “such a wealth of experience” as he looks to his future beyond Duke.

For more information about the team, including a full list of all team members, click here.

Ensuring post-radiation wellness for women

From left to right: seniors Danica Schwartz, Shernice Martin, Kayle Park, and Michelle Huang

Seniors Michelle Huang, Shernice Martin, Kayle Park, and Danica Schwartz (all pictured) were gathered around the poster for their team, Promoting Sexual Function and Pelvic Health in Women’s Healthcare.

The project has been around for three years and this year’s study, which looked at improving female sexual wellness after pelvic radiation procedures, was in fact a sister study to a study done two years prior on reducing anxiety surrounding pelvic exams.

As Huang described, graduate students and faculty conducted in-depth interviews with patients to better understand their lived experiences. This will help the team develop interventions to help women after life events that affect their pelvic and sexual health, such as childbirth or cancer treatment. These interventions are grounded in the biopsychosocial model of pain, which highlights the links between emotional distress, cognition, and pain processing.

For more information about the team, including a full list of all team members, click here.

From dolphins to humans

Sophomores Noelle Fuchs and Jack Nowacek were manning an interactive research display for their team, Learning from Whales: Oxygen, Ecosystems and Human Health. At the center of their research question is the condition of hypoxia, which occurs when tissues are deprived of an adequate oxygen supply.

Sophomores Noelle Fuchs and Jack Nowacek

Hypoxia is implicated in a host of human diseases, such as heart attack, stroke, COVID-19, and cancer. But it is also one of the default settings for deep-diving whales, who have developed a tolerance for hypoxia as they dive into the ocean for hours while foraging.

The project, which has been around for four years, has two sub-teams. Fuchs, an Environmental Science and Policy major, was on the side of the team genetically mapping deep-diving pilot whales, beaked whales, and offshore bottlenose dolphins off the coast of Cape Hatteras  to identify causal genetic variants for hypoxia tolerance within specific genes. Nowacek, a Biology and Statistics double-major, was on the other side of the research, analyzing tissue biopsies of these three cetaceans to conduct experiences on hypoxia pathways.  

The team has compiled a closer, more interactive look into their research on their website.

And when asked about her experience being on this team and doing this research, Fuchs remarked that Bass Connections has been a  “great way to dip my toe into research and figure out what I do and don’t want to do,” moving forward at Duke and beyond.

For more information about the team, including a full list of all team members, click here.

Post by Meghna Datta, Class of 2023

Rural Exodus: An Era of Climate-Migration

Amid fracturing arctic ice shelves, late September tempests, floods, droughts, jumping wildfires, a few decades of quick extinction and species blinking out like the quiet collapse of distant supernovae, our climate crisis has begun to displace humans en masse. 

68.5 million people were forcibly displaced by climate change and disasters in 2017. By 2021, that number grew to 89.3 million people. In 2022, we reached 100 million.

In a series of articles for the San Francisco News entitled “The Harvest Gypsies,” John Steinbeck described the 1930s Dust Bowl migrants in California’s Central Valley, uprooted by drought and crumbling wheat, then later novelized in the American classic Grapes of Wrath.

Steinbeck wrote, “The new migrants from the dust bowl are here to stay. They are the best American stock, intelligent, resourceful; and, if given a chance, socially responsible. To attempt to force them into a peonage of starvation and intimidated despair will be unsuccessful. They can be citizens of the highest type, or they can be an army driven by suffering to take what they need. On their future treatment will depend the course they will be forced to take.”

Alluding to Steinbeck, Dr. Robert McLeman joined Duke’s Dr. Sarah Bermeo for Climate Change, Adaptation and Migration, a conversation on climate-migration and rural impact central to Dr. Kerilyn Schewel’s Rural Development and the Capability to Stay project.

Co-sponsored by Duke Center for International Development (DCID) and the Center on Modernity in Transition (COMIT), the lecture is part of the larger Rural Transformations speaker series, highlighting rural perspectives in the discourse around development. This objective embodies COMIT’s research as well as their cognizance of “modernity as an age of transition towards a future world society—one that will emerge not through the universalization of any existing way of life, but rather through the sustained, creative, and complexly interacting contributions of all the diverse cultures and peoples of the world.”

The Dust Bowl, McLeman pointed out, is a quintessential example of climate migration, conjuring Dorothea Lange’s depression-era photojournalism and 8th grade US history. More recently, this phenomenon has been exemplified by hurricanes Katrina, Ike, Harvey, Irma, Sandy, Ida, Hugo, Andrew, Ian, and Maria (just to name a few) with similar, though smaller scale effects.

As McLeman and Bermeo acknowledged, climate-catalyzed movement is highly dependent on complex interactions between environment, society, economy, and politics, including a myriad of non-ecological factors like “land tenure, social networks, [and] access to government programs.” 

Dr. Robert McLeman is a Professor of Geography and Environmental Studies at Wilfrid Laurier University in Ontario, Canada and is the author of Climate and Human Migration: Past Experiences, Future Challenges

Their research on the demographic composition and rates of climate-migration answers a number of questions: who is disproportionately affected by climate change? Who is migrating? And who is participating in policy decisions?

December 2022, the Biden Administration announced a $135 million investment for relocation and adaptation planning for Native American tribes severely impacted by environmental crises, such as “coastal and riverine erosion, permafrost degradation, wildfire, flooding, food insecurity, sea level rise, hurricane impacts, potential levee failure and drought.”

In less than a lifetime, one such tribe, the Jean Charles Choctaw Nation in Terrebonne Parish, Louisiana, witnessed nearly their entire island sink into swampy silt. 

The sinking of Isle de Jean Charles, National Geographic

On their tribal website, they write: “For our Island people, [Isle de Jean Charles] is more than simply a place to live. It is the epicenter of our Tribe and traditions. It is where our ancestors survived after being displaced by Indian Removal Act-era policies and where we cultivated what has become a unique part of Louisiana culture.

Today, the land that has sustained us for generations is vanishing before our eyes.”

To date, 98% of the island has sunk. The tribe has begun relocation to the New Isle 40 miles north.    

Dr. Sarah Bermeo is a political economist, associate professor of Public Policy and Political Science in Duke’s Sanford School, and author of Targeted Development.

Climate migration in America, however, is not contained within and between states. In the past decade alone, Bermeo’s research points to a significant increase in migration from Central America to the US as well as novel patterns of family unit migration to the southern border (as opposed to a predominantly individual, male demographic in previous years). She attributes two recent droughts to this out-migration, disproportionately displacing rural communities whose livelihoods are integrally tied to subsistence farming and year-to-year crop yield. 

“People leave their homes because of climate but leave their countries for other reasons,” Bermeo explained. A large percentage of climate-migration is “inter-state,” i.e. a rural coastal community is forced to move inland (but still within their country) because of dangerous erosion.

“Central America’s choice: Pray for rain or migrate. Ravaged by drought, farmers in rural Honduras and Guatemala live on the edge of hunger,” reports NBC News.

In Central America, however, there is a distinct relationship between the incidence of drought and violence. Environmental stress has catalyzed a mass exodus from rural areas, increasing urbanization, yet these cities (particularly those in Honduras, Guatemala, and El Salvador) often rank globally among the most violent, based on year-to-year per capita homicide rates.

With high levels of urban corruption and gang affiliation, it is often difficult for rural “outsiders” to find employment in the cities, leaving them unable to compensate economically for a season of crop failure. This conflict is further exacerbated by large proportions of young workers in these populations. 

Despite deep-seated political polarization, climate-migration is adaptive. 

McLeman described migration generally as “neither good nor bad… something that people sometimes do and always have done… [But] in North America, we lose sight of the fact that it is normal human behavior… it’s the circumstances under which it occurs that creates the challenges.” 

When migration is voluntary, when people have access to social safety nets, are able to remit money to their families back home, and to mobilize legally across borders, migration is beneficial for the migrant, the migrant’s family, and the receiving community (which often benefits by filling labor demands). Often, the ramifications of immigration portrayed in the media (crime, destitution, etc.) are exacerbated by the lack of legality, social networks, and “gray markets.”

Bermeo acknowledged that the most effective mechanisms of decreasing undocumented migration are those that increase legal pathways. Historically, when the US has increased the number of visas allocated to Central American immigrants, illegal immigration subsequently decreased. 

The panelists agreed: in order for both the migrating and receiving communities to benefit, we must prioritize the dignity of migrating individuals.

Though conversations surrounding climate change feel threateningly existential, Bermeo and McLeman described ways in which climate adaptation can be manageable. When migrants and rural communities are excluded from conversations and subsequent policy-making, not only do they benefit less from the proposed and funded interventions, but other communities (perhaps at less imminent risk from climate change) will still suffer from this missing insight.

Here, I return to the Jean Charles Choctaw Nation. Despite the appearance of a successful relocation project, the tribal council released a press statement in 2022, condemning the state of Louisiana. Elder Chief Albert Naquin spoke on the issue:

“If you believe that the resettlement of Isle de Jean Charles was successful, you’re headed in the wrong direction.” The memo added that, “Moving people while trampling upon our Tribe’s inherent sovereignty and rights to self-determination and cultural survival must not be viewed as a ‘success’ for future public climate adaptation investments.” 

Dr. Kerilyn Schewel is a lecturing fellow at the Duke Center for International Development. She has received an award from the Social Science Research Council for her research project titled “Rural Development and the Capability to Stay.” 

The mass movement of climate-migrants, from Indigenous to rural communities, represents a loss of autonomy, of land integral to identity, and often of home. 

Still, Schewel’s Rural Transformation project advocates for the prioritization of these communities, rejecting the notion of passive policy-making and, instead, endorsing their active participation. Her project is indicative of how we must approach climate change adaptation: with empathy, education, and inclusion.

In a conversation with DCID, Schewel put it best: “[R]ural places are often treated as an afterthought… Some of the most promising advances in sustainable and equitable development are taking place in rural contexts, where a diversity of actors are striving to transform food systems, incorporate local knowledge, strengthen climate resilience, and widen participation in the development process.”

The DCID article ends with key insights from Schewel that encompass the Climate Change, Adaptation and Migration discussion and bear repetition: “As more focus is going towards migration, this is a project that will take very seriously the constraints on rural livelihoods and the motivations of migrants who leave rural places, while offering forward-looking solutions to advance our understanding of what it would mean to build more sustainable and flourishing rural futures.” 

Next up in the Rural Transformation lecture series: Religion and Development (June 20) and Local Knowledge, Global Change (June 30)

By Alex Clifford, class of 2024
By Alex Clifford, class of 2024

Into the Damp, Shady World of the Bryophytes

Clockwise: Jonathan Shaw, Adam Kosinski, Natalie Farris, and Kavya Menke looking at bryophytes on a log.

On a bright Sunday afternoon in April, I did something I had never done before. I went for a walk in the woods specifically to look for mosses. No, that’s not strictly true — we were looking for bryophytes. I learned, among other things, that not everything I had always called moss was really moss at all. (The word bryophyte comes from ancient Greek components and literally means “moss plant.”)

A patch of moss on the Al Buehler Trail. Moss is one type of bryophyte; liverworts and hornworts are the two others.

The walk was organized by Wild Ones, an undergraduate nature club I’m involved with. Biology Professor Jonathan Shaw, Ph.D., and Blanka Aguero, data and collections manager in the Duke University Herbarium, volunteered to teach a group of undergraduates about mosses and other bryophytes on the Al Buehler Trail adjacent to the Duke golf course.

Jonathan Shaw and members of the Wild Ones holding moss. Mosses, liverworts, and hornworts together represent the bryophytes.

Bryophytes (which include mosses, liverworts, and hornworts) represent one of several large groups of terrestrial plants. Other groups include angiosperms (flowering plants), gymnosperms (cone-producing plants like conifers and ginkgos), pteridophytes (vascular, spore-producing plants including ferns and horsetails), and lycophytes (an ancient group with about 1200 surviving members). According to Shaw, bryophytes are “the second biggest group after the flowering plants, but the flowering plants are an order of magnitude more diverse.” Aguero says that North Carolina has 462 moss species, 211 liverworts, and 7 hornworts.

Zach Pracher (Wild Ones member) and Blanka Aguero looking at bryophytes on a log.

Unlike the other terrestrial plant groups, bryophytes are nonvascular, meaning they lack the water transport tissues that other plants use. Without vascular tissue and without lignin for support, bryophytes can’t grow very big because they have no way to efficiently move water from their base to the rest of the plant. Instead, they grow close to the ground and absorb water directly from the environment into their cells.

Despite their preference for damp habitats, bryophytes can live for a long time without water. Some plants (like cacti) survive droughts by storing water, but bryophytes have a different strategy. They go into a state of dormancy, or suspended animation, and simply wait. Then, when it next rains, “they go hog-wild, photosynthesizing again in minutes,” Shaw says.

So if bryophytes don’t rely on constant moisture to survive, why do they like it so wet? Water, as it turns out, isn’t just important for hydration. Bryophytes rely on it to reproduce as well.

“Mosses are the amphibia of the plant communities,” Shaw says. Just as many amphibians can live on land but must return to the water to reproduce, bryophyte sperm has to “swim” to an egg cell to fertilize it. Therefore, they need water in order to reproduce, but they don’t need much. It could be mist from a splashing waterfall or a puddle in the woods or rainwater trickling down a tree. It could even be dew.

Moss on a tree trunk. Bryophytes can grow in a wide range of habitats across the world.

The day was warm and sunny, but the ground was dotted with puddles from recent storms. Armed with small hand lenses, we set off down the trail, stopping periodically to scrutinize tree bark, fallen logs, and thick patches of moss on the forest floor.

You need not travel far to find bryophytes. Mosses and their cousins colonize all sorts of hidden nooks: damp logs, trailside divots, tree bark, riverbanks, forgotten corners of backyards. Compared to seed-producing plants, bryophytes tend to have larger geographic ranges, perhaps in part because spores disperse more easily and because bryophytes can survive dry spells. Shaw estimates that about 75% of the moss species found in North Carolina are also found in Europe, and some of them are found in Asia as well.

Atrichum moss viewed through a hand lens. Note the thin line down the middle of each leaf. That line is a midrib and is one feature that sets mosses apart from liverworts.

We learned that most mosses have a midrib in the middle of each leaf, whereas liverworts have no midrib.

“A liverwort,” Shaw explains helpfully, “is like a moss, but it’s a liverwort.”

Liverworts are relatively flat in comparison to mosses because their leaves are in two parallel rows, whereas mosses tend to have a more spiral shape, with leaves emerging from all sides of the stem. The flat appearance of liverworts explains why they are sometimes called scale mosses. Another feature to consider if you’re trying to distinguish mosses and liverworts is the presence of lobed leaves, or leaves with protuberances off the main leaf (think of maple or oak leaves, for example). Some liverworts (but not all) have lobed leaves, but no mosses do.

A liverwort (main image) and the same liverwort viewed through a hand lens (top right). Liverworts and mosses can look very similar, but a hand lens makes it easier to spot the differences between them. Note the relatively flat appearance of the liverwort leaves compared to moss leaves, which tend to grow in a spiral fashion around the stem.

Aguero and Shaw both point out that the features we use to visually distinguish bryophytes aren’t necessarily the same features that officially set mosses and liverworts apart. The main difference between mosses and liverworts involves differences between their sporophytes.

Frullania is a genus of liverworts that forms dark patches, like the spots on this tree. If you see patches like these, Aguero says, they are “invariably” Frullania liverworts.

“It’s not true that if you’ve seen one moss, you’ve seen them all,” Shaw says. They’re small, yes, but they are not all the same.

We looked at one particularly lush patch of moss in the Bryoandersonia genus, named after a Duke professor. If you’re trying to identify trees, Shaw says, you might start with features like whether the leaves are broad or narrow and whether the tree is shrubby or not. With mosses, on the other hand, one of the first questions to ask is whether it’s pleurocarpous or acrocarpous. Pleurocarpous mosses, such as the Bryoandersonia we looked at, tend to have highly branching stems and grow in sprawling patches. The stems of acrocarpous mosses, meanwhile, have little or no branching and grow mostly vertically, often forming tight clumps.

Kavya Menke (Wild Ones member) examining a thallose liverwort we found by a stream.

After learning about patches of Frullania liverworts on trees from Aguero, we examined a large clump of liverworts growing beside a stream. Unlike the other liverworts we’d seen, this was a type of thallose liverwort, set apart from so-called leafy liverworts by the presence of thallus (a ribbon-like structure) instead of leaves. We also had the chance to smell it. Interestingly, liverworts also have a distinctive smell, sharp and earthy. The scent can be so strong that you might sometimes smell liverworts before you see them.

A thallose liverwort in the genus Conocephalum. Thallose liverworts are characterized by thalli (plural of thallus) instead of leaves. The other liverworts we saw were leafy liverworts.
Photo by Adam Kosinski.

According to Shaw, the term liverwort dates back to when botany and herbal medicine were considered largely the same. The so-called Doctrine of Signatures is the long-held idea that plants’ physical features reveal their medicinal uses. Thallose liverworts were thought to resemble livers and were used to treat ailments of the liver, hence the name. Similarly, the walnut looks rather like a brain and was used to treat mental illness, while the Dutchman’s breeches flower (the white flowers are said to resemble pants) was used for sexually transmitted diseases.

Aguero says that some liverworts do contain chemicals with antimicrobial properties, but she advises people not to eat liverworts.

Moss sporophytes, which release spores into the air. (Top right: close-up through hand lens.) The sporophytes are the only part of a bryophyte that are diploid (containing two sets of chromosomes instead of one). The trees in the background are also diploid; most plants (with the exception of bryophytes) are diploid during most of their life cycle.
Photos by Adam Kosinski.

Near the end of our walk, we found something we’d been keeping an eye out for but hadn’t yet seen: moss sporophytes. Bryophytes have a unique life cycle. Most of the time when we see a plant or an animal, it is diploid, meaning each cell contains two full sets of chromosomes (one from each parent). Every human cell, for instance, contains 46 chromosomes—with the exception of female egg and male sperm cells, which contain only 23. Cells that have only one set of chromosomes (like human egg and sperm cells) are called haploid. Plants undergo alternation of generations, meaning that one phase in their life cycle is haploid and one is diploid. In the case of most plants, the dominant and most conspicuous part of the life cycle is the diploid phase, but bryophytes are different. The fuzzy green carpets of moss we see are made of haploid cells, while the diploid phase is short-lived and only appears during reproduction. In mosses, the diploid phase (also known as the sporophyte) resembles thin filaments emerging from the haploid bed of moss. These sporophytes release spores (the spores are haploid) that grow into the next generation of moss.

“I wish we could be like the moss spores and let the wind carry us,” said Kavya Menke, one of the undergraduates on the walk. “Cheaper than Uber.”

Clockwise: Wild Ones members Natalie Farris, Adam Kosinski, and Zach Pracher examining patches of Frullania, a liverwort genus.

Occasionally, I paused my own bryophyte observations to watch others watching bryophytes. I found myself wondering if people are similarly bemused when they see me standing in a swamp with binoculars or crouching down on the way to class to move an earthworm off the sidewalk. I am accustomed to the world of birding, and looking for creatures like dragonflies, snakes, and salamanders feels natural to me as well. But this was a delightful opportunity to enter a world in which I had little to no experience: the shady, damp world of the bryophytes.

Adam Kosinski taking a close look at a bryophyte specimen placed on a log.

If you make a habit of going on walks with birders, you may spend a lot of time waking up before dawn, craning your neck upward, and straining to hear the alleged differences between a dozen kinds of short chirps. If you go out looking for snakes, you might spend a warm afternoon flipping over sun-warmed boards and scanning rocks and other basking spots. Searching for salamanders will likely involve scrutinizing wet soil, leaf litter, and ponds in early spring, possibly on a dark and rainy night. But searching for bryophytes is an experience all its own.

For one thing, you can go at any time of day and be equally successful, seeing as bryophytes neither crawl nor slither nor fly. You can also feel free to move as slowly as you wish. Aguero compares bryologists to lichenologists: “Moss people and lichen people work together frequently,” she says. “We walk similarly slowly.”

Blanka Aguero discussing bryophytes with students.
Photo by Adam Kosinski.

You could walk the same trail a hundred times and see it a hundred different ways. You could focus on birds or earthworms or snakes, wildflowers or changing leaves, clouds or trees or rocks. The next time you are in the mood to explore a new world, consider taking a walk — either somewhere new or a path you’ve walked a hundred times before — and turning your attention to the wonderful world of the bryophytes. Pet the moss. Feel its springiness and dampness and softness. Run your fingers lightly over the thin sporophyte stalks and notice how they tickle your palm. Smell the liverworts. See the dark patches of Frullania on a tree trunk. Bryophytes are nearly everywhere. Look for them. Look at them. See them.

Bryoandersonia moss viewed through a hand lens.
Photo by Adam Kosinski.

Post by Sophie Cox, Class of 2025

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