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Computer Science Students Say: Let’s Talk About Microaggressions

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Soon after taking a seat in her high-level computer science class, Duke student Kiara de Lande surveyed the room. The realization that she was one of only three women of color washed over her. It left a tang of discomfort and confusion. In her gut, she knew that she was capable of success. But then, why were there so few students that looked like her? Doubt ensued: perhaps this was not a place for her. 

de Lande was one of five members of the student advisory board for AiiCE (Alliance for Identity-Inclusive Computing Education) who reflected on their experiences as minority students in computer science in a virtual panel held Jan. 23.

As de Lande shared her story, undergraduate Kianna Bolante nodded in agreement. She too, felt that she had to “second-guess her sense of belonging and how she was perceived.” 

Berkeley ’24 graduate Bridget Agyare added that group work is crucial to success in CS classes, stressing the need for inclusion. The harm of peer micro-aggressions was brought up, the panel emphasizing the danger of stifling minority voices: “When in groups of predominantly males,” de Lande said, “my voice is on the back-burner.”

To not feel heard is to feel isolated, compounding the slam of under-confidence. Small comments here and there. Anxiety trickling in when the professor announces a group project. Peers delegating to you the “front-end” or “design” aspects, leaving the more intricate back-end components for themselves. It’s subtle. It feels like nothing glaring enough to bring attention to. So you shove the feelings to the side.

“No one reaches this level of education by mistake,” said Duke CS graduate student Jabari Kwesi. But over time, these subtle slights chip away at the assurance in your capabilities. 

Kwesi remembers the first time he spoke to a Black female professional software engineer (SWE). “Finally,” he said, “someone who understands what you’re talking about for your experience in and outside academia.”

He made this connection in a Duke course structured to facilitate conversations between students and professionals in the technology industry. In similar efforts, the Duke organization DTech is devoted to non-males in tech. Mentors provide support with peer advisors, social gatherings, and recruiter connections. It also provides access to a database of internships, guiding members during competitive job-hunting cycles. 

As university support continues to grow, students have not shied away from taking action. Bolante, for example, created her own social computing curriculum: focused on connecting student’s identities to the course material. The initiative reflects her personal realization of finding the value in her voice. 

“My personal experiences, opinions, ideas are things no one can take away from me. My voice is my strongest asset and power,” she said. 

As I listened to the declaration, I felt the resilience behind her words. It was evident that the AiiCE panelists are united in their passion for an inclusive and action-driven community. 

Kwesi highlighted the concept of “intentionality.” As a professor, one has to be conscious of the commitment to improvement. This includes making themselves available to students and accepting feedback. Some suggestions amongst the panel were “spotlights” on impactful minorities in CS. Similarly, in every technical class, mandating a societal impact section is key. Technology does not exist in a vacuum: deployment affects real people. For example, algorithms are susceptible to biases against certain groups. Algorithms are designed for tools like resume scanners and medical evaluations. These are not just lines of code- people’s livelihoods are at stake. With the surge of developments in artificial intelligence, technology is advancing more rapidly than ever. To keep bias in check, assembling interdisciplinary teams can help ensure diverse perspectives.

Above all, we must be willing to continue this conversation. There is no singular curriculum or resource that will permanently correct inequities. Johns Hopkins ’25 graduate Rosa Gao reminded the audience that inclusivity efforts are “a practice,” and “a way of moving through space” for professors and peers alike.

It can be as simple as a quick self-evaluation. As a peer: “Am I being dismissive?” “Am I holding everyone’s opinions at an equal weight?” As a professor: “How can I create assignments that will leverage the student voice?”

Each individual experience must be valued, and even successful initiatives should continue to be reinvented. As minorities, to create positive change, we must take up space. As a greater community, we must continue to care, to discuss, and to evolve. 

By Ana Lucia Ochoa, Class of 2026

Glowing Waterdogs and Farting Rivers: A Duke Forest Research Tour

Jonny Behrens looks for aquatic macroinvertebrates with Duke Forest Research Tour participants.

“Who would be surprised if I told you that rivers fart?”

Nick Marzolf, Ph.D., went on to explain that streams release greenhouse gases from decaying matter and gas-producing bacteria. This revelation was one of several new facts I learned at the annual Duke Forest Research Tour in December.

“First and foremost,” says Duke Forest Senior Program Coordinator Maggie Heraty, “the Duke Forest is a teaching and research laboratory.” The Office of the Duke Forest hosts an annual Research Tour to showcase research activities and connect to the wider community. “Connecting people to science and nature, and demystifying scientific research, is a key part of our goals here,” Heraty says.

Duke Forest, which consists of over 7,000 acres in  Durham, Orange, and Alamance Counties, lies within the Cape Fear and Neuse river basins, two of seventeen river basins in North Carolina. What exactly is a river basin? Heraty quoted a poetic definition from North Carolina Environmental Education:

“A river basin encompasses all the land surface drained by many finger-like streams and creeks flowing downhill into one another and eventually into one river, which forms its artery and backbone. As a bathtub catches all the water that falls within its sides and directs the water out its drain, a river basin sends all the water falling within its surrounding ridges into its system of creeks and streams to gurgle and splash downhill into its river and out to an estuary or the ocean.”

Located within the Cape Fear River Basin, the headwaters of New Hope Creek, which passes through the Korstian Division of Duke Forest, are fed by roughly 33,000 acres of land, over 5,000 of which are in the Duke Forest. Land outside of the Forest is of vital importance, too. Duke Forest is working in partnership with other local conservation organizations through the Triangle Connectivity Collaboration, an initiative to connect natural areas, create wildlife corridors, reduce habitat fragmentation, and protect biodiversity in the Triangle region.

New Hope Creek in the Korstian Division of the Duke Forest.

Dwarf waterdogs

We walked down a short trail by the creek, and the tour split into two groups. Our group walked farther along the stream to meet two herpetologists studying the elusive dwarf waterdog.

Bryan Stuart, Ph.D., Research Curator of Herpetology at the North Carolina Museum of Natural Sciences, and Ron Grunwald, Ph.D., Duke University Senior Lecturer Emeritus, are involved in a study looking for dwarf waterdog salamanders (Necturus punctatus) in New Hope Creek. Dwarf waterdogs are paedomorphic, Stuart said, meaning they retain larval characteristics like external gills and a flat tail throughout their lives. In fact, the genus name Necturus means “tail swimmer” in reference to the species’s flat tail.

According to Stuart, on October 3, 1954, Duke professor and herpetologist Joe Bailey collected a dwarf waterdog in New Hope Creek. It was the first record of the species in Orange County.

The Duke Forest is in the westernmost part of the species’ Piedmont range, though it extends farther west in parts of the sandhills. “To have a dwarf waterdog record in Orange County—that’s almost as interesting as it gets,” Stuart said.

Ron Grunwald and Bryan Stuart discuss dwarf waterdog research at New Hope Creek.
Photo provided by The Office of the Duke Forest.

In the late 1960s, Michael A. Fedak, Bailey’s graduate student, did a thesis on dwarf waterdogs in the area. His specimens are still stored in the collections of the North Carolina Museum of Natural Sciences.

No one had studied this population since—until now.

Dwarf waterdogs are very sensitive to pollution and habitat disturbance, Stuart said, on top of the fact that New Hope Creek is already at the edge of the species’s habitat. When Fedak studied them several decades ago, the salamanders were abundant. Are they still?

Stuart, Grunwald, and other researchers want to find out. “The challenge of salamander biology,” Grunwald said, “is that it always happens when it’s freezing.” Surveying salamander populations, he explains, isn’t like watching birds or counting trees. It requires you to go where the salamanders are, and for dwarf waterdog research, that means dark, cold streams on nights when the water temperature is below 55 degrees Fahrenheit.

Researchers bait funnel traps with chicken liver or cat food and set them underwater overnight. Sometimes they catch crayfish. Sometimes they catch nothing. And sometimes they catch exactly what they’re hoping to find: the elusive dwarf waterdog. After all this time, these slippery, nocturnal, chicken-liver-loving salamanders are still here.

Two dwarf waterdogs in a funnel trap before being released back into New Hope Creek.

Though the traps have been successful at capturing some individuals, they will never catch them all, so researchers calculate the recapture rate to estimate the total population. Imagine a bag of rice, Grunwald said. You could count each individual grain, but that would be challenging and time-consuming. Alternatively, you could pull out one grain of rice, color it, and put it back in the bag, then estimate the total number by calculating the probability of pulling out the same colored grain of rice again. In a very small bag, you might draw the same rice grain several times. But the more rice you have, the less likely you are to draw the same grain twice.

To figure out if any of the dwarf waterdogs they catch are recaptures, the researchers mark each individual with a visual implant elastomer, which is “just a fancy way of saying rubber that we can see,” Grunwald said. The material is injected under a salamander’s “armpit” with a small syringe, creating a pattern visible under ultraviolet light. With two colors (fluorescent yellow and red) and four possible injection locations (one behind each leg), there are plenty of distinct combinations. Grunwald showed us a waterdog that had already been marked. Under a UV flashlight, a spot just below its right foreleg glowed yellow.

Captured dwarf waterdogs are injected with a special rubber material that glows under a UV light. Each salamander is marked with a distinct pattern so researchers can recognize it if it’s ever recaptured.

Establishing a recapture rate is essential to predicting the total population in the area. The current recapture rate? Zero. The sample size so far is small—about a dozen individuals—and none of them have been caught twice. That’s an obstacle to statistical analysis of the population, but it’s good news for the salamanders. Every new individual is one more dwarf waterdog survivor in New Hope Creek.

Ron Grunwald with Research Tour participants looking at dwarf waterdogs in bags.
Photo provided by The Office of the Duke Forest.

Stream health

Next, at a different spot along the stream, we met Nick Marzolf, Ph.D., a postdoctoral scholar, and Jonny Behrens, a Ph.D. student, to learn more about New Hope Creek itself. Marzolf and Behrens have both been involved with aquaterrestrial biogeochemistry research in the lab of Emily Bernhardt, Ph.D., at Duke University.

Nick Marzolf (right) and Jonny Behrens discuss stream health.
Photo provided by The Office of the Duke Forest.

Protecting New Hope Creek requires understanding individual organisms—like dwarf waterdogs—but also temperature, precipitation, oxygen levels, pesticide runoff, and biodiversity overall. When humans get stressed, Behrens said, different organs have different physiological reactions. Similarly, different organisms in a stream play different roles and respond to stress in different ways.

Jonny Behrens and Research Tour participants look at aquatic macroinvertebrate samples.
Photo provided by The Office of the Duke Forest.

Behrens passed around vials containing aquatic macroinvertebrates—specimens big enough to see with the naked eye—such as the larvae of mayflies, crane flies, stoneflies, and dragonflies. They are known for being good indicators of stream health because there are many species of macroinvertebrates, and they have different tolerances to stressors like pollution or changes in water temperature.

Aquatic macroinvertebrates can indicate the health of a stream through their species diversity and abundance.
Photo provided by The Office of the Duke Forest.

The water downstream of a nearby wastewater treatment plant is much warmer in winter than other waterways in the area, so researchers see more emergent adult midges and caddisflies there than they do here. Aside from temperature, organisms need to adapt to other changing conditions like oxygen levels and storms.

“Rain is really fun to watch in streams,” Behrens said. The water level rises, pulling up organic matter, and sand bars change. You can tell how high the water got in the last storm by looking for accumulated debris on trees along river banks.

Farting rivers and the peanut butter cracker hypothesis

Marzolf studies hydrology, or “how water moves through not only the landscape but also the river itself.”

Nick Marzolf demonstrates a technique to measure gasses in streams using a syringe.

Part of his research involves measuring gases in water. Streams, like cars and cows and people, release greenhouse gases, including carbon dioxide and methane. In fact, Marzolf and colleagues hypothesize that New Hope Creek contributes more CO2 to the atmosphere per unit area than anywhere else in the Duke Forest.

Decaying matter produces CO2, but that isn’t the only source of greenhouse gasses in the creek. Microscopic organisms, like methane-producing bacteria, produce gases as well.

The “peanut butter cracker hypothesis,” Marzolf said, compares organic matter such as leaves to a cracker, while the “peanut butter,” which makes the cracker more palatable, is the microbes. Scrumptious.

Disturbing the sediment at the bottom of New Hope Creek causes bubbles to rise to the surface due to the metabolic activities of gas-producing bacteria.

Marzolf turned to Behrens. “Do you want to walk around and see if you can stir up some methane bubbles?” Behrens waded into the stream, freeing bubbles from the pressure of the overlying water keeping them in leaf mats. We watched the bubbles rise to the surface, evidence of the activities of organisms too small to see.

Behrens walks around in New Hope Creek to stir up gas bubbles from aquatic bacteria.

Restoring a stream to protect its pigtoe

Finally, Sara Childs, Executive Director of the Duke Forest, discussed stream restoration projects. Though structures in the Duke Forest like remnants of old mills and dams can alter and damage ecosystems, they can also have historical and cultural significance. Duke Forest prioritizes restoration projects that have meaningful ecological, teaching, and research benefits while honoring the history of the land.

For instance, the Patterson Mill Dam was built in the late 1700s and probably remained in use for about 100 years. The stream has already adapted to the structure’s presence, and there isn’t necessarily ongoing degradation because of it. Duke Forest restoration projects, Childs said, don’t revolve around very old structures like the Patterson Mill Dam. Instead, they are planning to remove two more recent structures that are actively eroding banks, threatening wildlife habitat, and creating impounded, oxygen-poor areas in the stream.

One of the structures they are hoping to remove is a concrete bridge that’s endangering a threatened freshwater mussel species called the Atlantic pigtoe (Fusconaia masoni). Freshwater mussels, according to Childs, require a fish species to host the developing mussel larvae on their gills, and the Atlantic pigtoe favors the creek chub (Semotilus atromaculatus). The concrete bridge forms a barrier between the pigtoe and the chub, but removing it could reunite them.

Before starting construction, they will relocate as many mussels as possible to keep them out of harm’s way.

New Hope Creek, home to waterdogs and pigtoe and farting microbes, is precious to humans as well. Heraty describes it as “a really spectacular and beautiful waterway that we are lucky to have right in our backyards here in Durham.”

Post by Sophie Cox, Class of 2025

Carrying on Dr. King’s Legacy: The Fight for Equity in Obesity Treatment

“Of all the forms of inequality” Dr. Martin Luther King Jr. once said in a 1966 press conference, “injustice in health is the most shocking and the most inhumane.”

In honor of King’s impact on public health, Duke’s dean of Trinity College Dr. Gary G. Bennett delivered a powerful address Jan. 12 at the Trent Semans Center. Entitled ‘You have to Keep Moving Forward: Obesity in High-Risk Populations,’ Bennett discussed America’s Obesity Epidemic, and its disproportionate effects on Black women.

“More than 40% of the American population has obesity,” Bennett began. Incidence rates among Black women are the highest and have been since the epidemic began in 1955. “These disparities have not closed, and in many cases, they’ve widened over the years,” Bennett said.

Raisi-Estabragh 2023

Type two diabetes, hypertension, and cardiovascular disease are just some of the health risks associated with obesity. Compared to other racial groups, Black women are more likely to suffer from these conditions, as well as die from their effects. Furthermore, it appears that the efficacy of treatment options is significantly lower for patients of African descent.

But why do such disparities exist in the first place? According to Bennett, they can be attributed to a range of internal and external factors. “There certainly are physiological variations that are worth noting here, which is perhaps a challenge in all of obesity research.”

Research published in the journal Nature in 2022 found that, while there are different forms of obesity, that have shared ‘genetic and biological underpinnings.’ Environmental factors are also driving disparities. Black women are “exposed to more obesogenic environments, food desserts,” Bennett explained.  With limited access to affordable and nutritious food, options for healthy eating are slim.

But perhaps most interestingly, Black women also have a range of sociocultural factors at play. “There are fewer within-group social pressures to lose weight,” Bennett maintained. Other sociocultural factors include higher body image satisfaction and higher weight misperception. “This is problematic in some ways,” he continued. While it protects against certain eating disorders and low self-esteem, “It does challenge your ability to achieve weight loss.”

For Black women, obesity is a complex public health issue that needs to be addressed.

But how? From medication to surgery, there are myriad potential treatment options. According to Bennett, however, the real key is lifestyle intervention. “It really is the foundation.” Comprised of three parts: reduced calorie diet, physical activity, and self-monitoring, lifestyle intervention is able to reach the widest range of participants.

Like other treatment options, the lifestyle intervention route shows racial disparities in its outcomes. Because of this, Dr. Bennett’s work focuses on developing methods that are designed with Black patients in mind.

At the forefront of his research is a new online intervention called iOTA, which stands for Interactive Obesity Treatment Approach. “This is a digital obesity approach that we designed specifically for high-risk populations.” The platform personalizes weight loss goals and feedback, which assist in program retention.

In addition, participants are equipped with coaching support from trained medical professionals. “This IOTA approach does a bunch of things,” Bennett said. “It promotes weight loss and prevents weight gain, improves cardiometabolics,” along with a host of other physical benefits. Results also show a reduction in depressive symptoms and increased patient engagement. Truly incredible.

Scholars like Bennett have continued the fight for public health equity- a fight advocated for by Dr. King many years ago. For more information on Bennett and his work, you can visit his website here.

Written by Skylar Hughes | Class of 2025

Traveling With Friends Helps Even Mixed-Up Migrators Find Their Way

North American monarch butterflies migrate each winter to just a few mountaintops in central Mexico, with help from an internal compass that guides them home. New computer modeling research offers clues to how migrating animals get to where they need to go, even when their magnetic compass leads them astray. Credit: Jesse Granger, Duke University

DURHAM, N.C. — Some of us live and die by our phone’s GPS. But if we can’t get a signal or lose battery power, we get lost on our way to the grocery store.

Yet animals can find their way across vast distances with amazing accuracy.

Take monarch butterflies, for example. Millions of them fly up to 2,500 miles across the eastern half of North America to the same overwintering grounds each year, using the Earth’s magnetic field to help them reach a small region in central Mexico that’s about the size of Disney World.

Or sockeye salmon: starting out in the open ocean they head home each year to spawn. Using geomagnetic cues they manage to identify their home stream from among thousands of possibilities, often returning to within feet of their birthplace.

Now, new research offers clues to how migrating animals get to where they need to go, even when they lose the signal or their inner compass leads them astray. The key, said Duke Ph.D. student Jesse Granger: “they can get there faster and more efficiently if they travel with a friend.”

When their internal compasses go bad, migrating animals like these sockeye salmon don’t stop to ask directions. But they succeed if they stay with their fellow travelers. Credit: Jonny Armstrong, USGS

Many animals can sense the Earth’s magnetic field and use it as a compass. What has puzzled scientists, Granger said, is the magnetic sense is not fail-safe. These signals coming from the planet’s molten core are subtle at the surface. Phenomena such as solar storms and man-made electromagnetic noise can disrupt them or drown them out.

It’s as if the ‘needle’ of their inner compass sometimes gets thrown off or points in random directions, making it hard to get a reliable reading. How do some animals manage to chart a course with such a noisy sensory system and still get it right?

“This is the question that keeps me up at night,” said Granger, who did the work with her adviser, Duke Biology Professor Sönke Johnsen.

Multiple hypotheses have been put forward to explain how they do it. Perhaps, some scientists say, migrating animals average multiple measurements taken over time to get more accurate information.

Or maybe they switch from consulting their magnetic compass to using other ways of navigating as they near the end of their journey — such as smell, or landmarks — to narrow in on their goal.

In a paper published Nov. 16 in the journal Proceedings of the Royal Society B, the Duke team wanted to pit these ideas against a third possibility: That some animals still manage to find their way, even when their compass readings are unreliable, simply by sticking  together.

To test the idea, they created a computer model to simulate virtual groups of migrating animals, and analyzed how different navigation tactics affected their performance.

The animals in the model begin their journey spread out over a wide area, encountering others along the route. The direction an animal takes at each step along the way is a balance between two competing impulses: to band together and stay with the group, or to head towards a specific destination, but with some degree of error in finding their bearings.

The scientists found that, even when the simulated animals started to make more mistakes in reading their magnetic map, the ones that stuck with their neighbors still reached their destination, whereas those that didn’t care about staying together didn’t make it.

“We showed that animals are better at navigating in a group than they are at navigating alone,” Granger said.

Even when their magnetic compass veered them off course, more than 70% of animals in the model still made it home, simply by joining with others and following their lead. Other ways of compensating didn’t measure up, or would need to guide them perfectly for most of the journey to accomplish the same feat.

But the strategy breaks down when species decline in number, the researchers found. The team showed that animals who need friends to find their way are more likely to get lost when their population shrinks below a certain density.

Prior to the 1950s, tens of thousands of Kemp’s ridley sea turtles could be seen nesting near Rancho Nuevo, Mexico on a single day. By the mid-1980s the number of nesting females had dropped to a few hundred.

“If the population density starts dropping, it takes them longer and longer along their migratory route before they find anyone else,” Granger said.

Previous studies have made similar predictions, but the Duke team’s model could help future researchers quantify the effect for different species. In some runs of the model, for example, they found that if a hypothetical population dropped by 50% — akin to what monarchs have experienced in the last decade, and some salmon in the last century — 37% fewer of the remaining individuals would make it to their destination.

“This may be an underappreciated aspect of concern when studying population loss,” Granger said.

This research was supported in part by the Air Force Office of Scientific Research (FA9550-20-1-0399) and by a National Defense Science & Engineering Graduate Fellowship to Jesse Granger.

CITATION: “Collective Movement as a Solution to Noisy Navigation and its Vulnerability to Population Loss,” Jesse Granger and Sönke Johnsen. Proceedings of the Royal Society B, Nov. 16, 2022. DOI: 10.1098/rspb.2022.1910

Robin Smith
By Robin Smith

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