In some parts of the world, animals are going extinct before scientists can even name them.
Such may be the case for mouse lemurs, the saucer-eyed, teacup-sized primates native to the African island of Madagascar.
Various species of mouse lemurs found in Madagascar. Photos by Sam Hyde Roberts
There, deforestation has prompted the International Union for the Conservation of Nature (IUCN) to classify some of these tree-dwelling cousins as “endangered” even before they are formally described.
Duke professor Anne Yoder has been trying to take stock of how many mouse lemur species are alive today before they blink out of existence.
It’s not an easy task. Mouse lemurs are shy, they only come out at night, and they live in hard-to-reach places in remote forests. To add to the difficulty, many species of mouse lemurs are essentially lookalikes. It’s impossible to tell them apart just by peering at them through binoculars.
When Yoder first started studying mouse lemurs some 25 years ago, there were only three distinct species recognized by scientists. Over time and with advances in DNA sequencing, researchers began to wonder if what looked like three species might actually be upwards of two dozen.
In a new study, Yoder and dozens of colleagues from Europe, Madagascar and North America compiled and analyzed 50 years of hard-won data on the physical, behavioral and genetic differences among mouse lemurs to try to pin down the true number.
While many mouse lemur species look alike, they have different diets, and males use different calls to find and woo their mates, the researchers explain.
By pinning down their number and location, researchers hope to make more informed decisions about how best to help keep these species from the brink.
The study was published Sept. 27 in the journal Nature Ecology & Evolution.
Braxton Craven Distinguished Professor of Evolutionary Biology, Anne Yoder was director of the Duke Lemur Center from 2006 to 2018.
Look at the nearest window. What did you see first—the glass itself or what was on the other side? For birds, that distinction is a matter of life and death.
A dead red-eyed vireo above the entrance to the Brodhead Center at Duke. Every year, millions of birds die after colliding with windows. Buildings with lots of glass are particularly dangerous.
Every year, up to one billion birds die from hitting windows. Windows kill more birds than almost any other cause of human-related bird mortality, second only to feral and domestic cats. Both the transparency and reflectiveness of glass can confuse flying birds. They either don’t see the glass at all and try to fly through it, or they’re fooled by reflections of safe habitat or open sky. And at night, birds may be disoriented by lit-up buildings and end up hitting windows by mistake. In all cases, the result is usually the same. The majority of window collision victims die on impact. Even the survivors may die soon after from internal bleeding, concussions, broken bones, or other injuries.
Madison Chudzik, a biology Ph.D. student in the Lipshutz Lab at Duke, studies bird-window collisions and migrating birds. “Purely the fact that we’ve built buildings is killing those birds,” she says.
Every spring and fall, billions of birds in the United States alone migrate to breeding and wintering grounds. Many travel hundreds or thousands of miles. During peak migration, tens of thousands of birds may fly across Durham County in a single night. Not all of them make it.
Chudzik’s research focuses on nocturnal flight calls, which migrating birds use to communicate while they fly. Many window collision victims are nocturnal migrants lured to their deaths by windows and lights. Chudzik wants to know “how we can use nocturnal flight calls as an indicator to examine collision risks in species.”
Chudzik (back) setting up one of her recording devices on the Museum of Science and Industry in Chicago. The devices record flight calls from birds migrating at night. Image courtesy of Chudzik.
Previous research, Chudzik says, has identified a strong correlation between the number of flight calls recorded on a given night and the overall migration intensity that night. “If sparrows have a high number of detections, there is likely a high number migrating through the area,” Chudzik explains. But some species call more than others, and there is “taxonomic bias in collision risk,” with some species that call more colliding less and vice versa. Chudzik is exploring this relationship in her research.
Unlike bird songs, nocturnal flight calls are very short. The different calls are described with technical terms like “zeep” and “seep.” Chudzik is part of a small but passionate community of people with the impressive ability to identify species by the minute differences between their flight calls. “It’s a whole other world of… language, basically,” Chudzik says.
Chudzik can identify a species not only by hearing its flight call but also by seeing its spectrogram, a visual representation of sound. This spectrogram, from a recording on Adler Planetarium, has flight calls from four species. The x-axis represents time, while the y-axis shows frequency. The brightness or intensity indicates amplitude. Image from Chudzik.
She began studying nocturnal flight calls for research she did as an undergraduate, but her current project no longer needs to rely on talented humans to identify every individual call. A deep learning model called Nighthawk, trained on a wealth of meticulous flight call data, can identify calls from their spectrograms with 95% accuracy. It is free and accessible to anyone, and much of the data it’s been trained on comes from non-scientists, such as submissions from a Facebook community devoted to nocturnal flight calls. Chudzik estimates that perhaps a quarter of the people on that Facebook page are researchers. “The rest,” she says, “are people who somehow stumbled upon it and… fell in love with nocturnal flight calling.”
In addition to studying nocturnal flight calls, Chudzik’s research will investigate how topography, like Lake Michigan by Chicago, affects migration routes and behavior and how weather affects flight calls. Birds seem to communicate more during inclement weather, and bad weather sometimes triggers major collision events. Last fall in Chicago, collisions with a single building killed hundreds of migratory birds in one night.
Chudzik had a recorder on that building. It had turned off before the peak of the collision event, but the flight call recordings from that night are still staggering. In one 40-second clip, there were 300 flight calls identified. Normally, Chudzik says, she might expect a maximum of about seven in that time period.
Nights like these, with enormous numbers of migrants navigating the skies, can be especially deadly. Fortunately, solutions exist. The problem often lies in convincing people to use them. There are misconceptions that extreme changes are required to protect birds from window collisions, but simple solutions can make a huge difference. “We’re not telling you to tear down that building,” Chudzik says. “There are so many tools to stop this from happening that… the argument of ‘well, it’s too expensive, I don’t want to do it…’ is just thrown out the window.”
A yellow-bellied sapsucker collision casualty in front of the French Family Science Center last year.
What can individuals and institutions do to prevent bird-window collisions?
Turn off lights at night.
For reasons not completely understood, birds flying at night are attracted to lit-up urban areas, and lights left on at night can become a death trap. Though window collisions are a year-round problem, migration nights can lead to high numbers of victims, and turning off non-essential lights can help significantly. One study on the same Chicago building where last year’s mass collision event occurred found that halving lighted windows during migration could reduce bird-window collisions by more than 50%.
Chudzik is struck by “the fact that this is such a big conservation issue, but it literally just takes a flip of a switch.” BirdCast and Audubon suggest taking actions like minimizing indoor and outdoor lights at night during spring and fall migration, keeping essential outdoor lights pointed down and adding motion sensors to reduce their use, and drawing blinds to help keep light from leaking out.
Use window decals and other bird-friendly glass treatments.
There are many products and DIY solutions intended to make windows safer for birds, like window decals, external screens, patterns of dots or lines, and strings hanging in front of a window at regular intervals. For window treatments to be most effective, they should be applied to the exterior of the glass, and any patterning should be no more than two inches apart vertically and horizontally. This helps protect even the smallest birds, like kinglets and hummingbirds.
It can be hard to see from a distance, but these windows on Duke’s Fitzpatrick Center have been retrofitted with tiny white dots, an effective strategy to reduce bird-window collisions.
A 2016 window collision study at Duke conducted by several scientists, including Duke Professor Nicolette Cagle, Ph.D., identified the Fitzpatrick Center as a window collision hotspot. As a result, Duke retrofitted some of the building’s most dangerous windows with bird-friendly dot patterning. Ongoing collision monitoring has revealed about a 70% reduction in collisions for that building since the dots were added.
One obstacle to widespread use of bird-friendly design practices and window treatments is concerns about aesthetics. But bird-friendly windows can be aesthetically pleasing, too, and “Dead birds hurt your aesthetic anyway.”
If nothing else, don’t clean your windows.
Bird-window collisions don’t just happen in cities and on university campuses. In fact, most fatal collisions involve houses and other buildings less than four stories tall. Window treatments like the dots on the Fitzpatrick building can be costly for homeowners, but anything you can put on the outside of a window will help.
“Don’t clean your windows,” Chudzik suggests—smudges may also help birds recognize the glass as a barrier.
Window collisions at Duke
The best thing Duke could do, Chudzik says, is to be open to treating more windows. Every spring, students in Cagle’s Wildlife Surveys class, which I am taking now, collect data on window collision victims found around several buildings on campus. Meanwhile, a citizen science iNaturalist project collects records of dead birds seen by anyone at campus. If you find a dead bird near a window at Duke, you can help by submitting it to the Bird-window collisions project on iNaturalist. Part of the goal is to identify window collision hotspots in order to advocate for more window treatments like the dots on the Fitzpatrick Center.
Spring migration is happening now. BirdCast’s modeling tools estimate that 260,000 birds crossed Durham County last night. They are all protected under the Migratory Bird Treaty Act. However, Chudzik says, “We haven’t thought to protect them while they’re actually migrating.” The law is intended to protect species that migrate, but “it’s not saying ‘while you are migrating you have more protections,’” Chudzik explains. Some have argued that it should, however, suggesting that the Migratory Bird Treaty Act should mandate safer windows to help protect migrants while they’re actually migrating.
“This whole world comes alive while we’re asleep, and… most people have no idea,” Chudzik says about nocturnal flight calls. She is shown here on Northwestern University, one of the Chicago buildings where she has placed recorders for her research. Photo courtesy of Chudzik.
We can’t protect every bird that passes overhead at night, but by making our buildings safer, we can all help more birds get one step closer to where they need to go.
Imagine lying on your back, legs flailing, unable to flip yourself over. To make matters worse, there is a rope attached to your head that you can’t remove. Meanwhile, a giant is prodding at you with a long metal stick, and you can’t figure out if she’s trying to hurt you or help you.
Earlier this semester, I was that giant.
A tiny insect on its back under a microscope. Note the strand of lint caught on its beak.
I was in the entomology lab in the basement of the biology building on a Friday night, photographing insects under a microscope. One of them, so tiny that I could barely see it with the naked eye, had ended up on its back with its beak-like mouth caught on a miniscule thread of lint. I was using a pin to try to remove the lint, but my efforts were dragging the insect haphazardly across the leaf it was on, and I gave up out of fear of hurting it. Under the microscope, the insect’s situation was dramatic and hard to watch, but when I walked to the Duke Gardens later that night to release it, it was just a dark speck in my palm.
A candy-striped leafhopper viewed through a microscope.
Photographing insects for the entomology class I am taking this semester gives me perspective on a world that operates on a smaller scale, with obstacles humans don’t have to contend with—like pieces of lint ensnaring our mouths. But in order to photograph insects, I need them to stay reasonably still. Fred Nijhout, Ph.D., who teaches the entomology course, taught us that you can keep live insects in a refrigerator temporarily, which doesn’t kill them but slows their metabolism down significantly, making them easier to photograph. In the past few months, I have spent many hours with refrigerated insects.
As much as I love insects, I was terrified of this class. I thought it would require making a physical insect collection—which, in turn, would require me to kill insects, and I simply didn’t think I’d be able to do that. Fortunately, there was an option to create a photography collection with living insects instead, which is why I’ve spent so much time catching, photographing, and releasing insects over the past several weeks. We need to collect or photograph twelve insect orders and twenty families, which has led to some unusual situations — like sheer delight upon finding a termite or cockroach. (Both represent orders that, until recently, I didn’t have in my collection.)
A fly under a microscope.
The first insect I refrigerated was a tiny lace bug I found wandering across my pants one afternoon. I coaxed it onto my hand and ran to my dorm to get a vial. (I have since learned to keep small containers with me nearly everywhere I go.) I put the lace bug inside the vial and stuck it in the common room refrigerator overnight, wrapped discreetly in a plastic bag. I had serious misgivings. Could such a small creature really survive an entire night in a refrigerator? And what if someone found it and threw it away? The next morning, I retrieved it with much apprehension. The insect wasn’t moving. It seemed somehow lighter, more desiccated, and I was certain it was dead. What had I done?
A lace bug, the first insect I refrigerated. I didn’t notice the intricate structures protruding from its body until I saw it under a microscope.
I brought the lace bug to class and put it back in the refrigerator. Later that day, Nijhout showed me how to photograph it with the microscope camera. It remained motionless while we maneuvered it this way and that. But then, just as we were about to take another picture, one of its tiny antennae wiggled. It was alive. After all those hours in the refrigerator, it was still alive. I won’t soon forget that wiggling antenna. It felt miraculous in the most literal sense of the word.
Watching a refrigerated insect “wake back up” never ceases to amaze me. When a butterfly that was lying on its side suddenly flaps its wings and rights itself, or a curled-up damselfly begins to twitch after several minutes of total stillness, or a lace bug regains the ability to wiggle an antenna, I always feel like I am witnessing something remarkable. But my favorite part of the whole process might be what happens next.
After I’ve finished photographing an insect, I always try to release it, ideally wherever I found it. It is always a relief to put them back where they belong, alive and moving and hopefully unharmed. But it can be hard to let them go. Spending enough time with one creature, any creature, turns it into an individual, and once you’ve become acquainted with an individual, it’s hard not to care what happens to it. After I release an insect, I will never know its fate. But if cooperating with refrigeration and photography is the insects’ part of the deal, then releasing them afterward is mine.
An ailanthus webworm moth eating mango syrup with its straw-like proboscis.
Sometimes, I make more literal deals with the insects. One day, I caught an ailanthus webworm moth, a bright orange insect with black and white markings, and it kept reviving before I could get a good picture. Each time I relegated it back to the refrigerator, I felt worse and worse. So I put the moth back in the fridge one more time, promising that it would be the last, and walked to the dining hall, where I squirted mango syrup onto a napkin. I tried to be subtle so no one would ask me why I was putting it on a napkin instead of in a cup of iced tea. Oh, I’m just feeding the refrigerated moth in the insect lab. Nothing unusual. Have a great day! Back in the lab, I dabbed some syrup onto the back of my notebook and offered it to the moth, partly as a reward for its patience, partly to assuage my own guilt, and partly as a last-ditch attempt to keep the moth still while I photographed it. The moth became completely focused on lapping up the syrup, but I had failed to account for its feeding process, an exuberant dance that was anything but still. Nevertheless, a deal is a deal—that moth wasn’t going back in the fridge. I walked across campus to the spot where I’d found it, and it kept eating the sugary treat the whole time. For once, my photography subject didn’t seem eager to leave.
At Nijhout’s suggestion, I left this beetle at room temperature overnight, in a jar with some water droplets, instead of refrigerating it.
The mango syrup retrieval mission probably isn’t the strangest thing I’ve done in pursuit of insects. One morning, I was standing outside in the pouring rain, already soaked and so no longer remotely concerned about getting wetter, and holding my arms above my head in an awkward position while I tried to remove the slippery cap from an insect container in order to catch a candy-striped leafhopper perched on a leaf above me.
Another time, our class was on a field trip on the Al Buehler Trail when I spotted a dainty insect almost floating through the sun-dappled swamp. Nijhout identified it as a phantom crane fly, and when I failed to catch it in a dignified manner from the boardwalk, I jumped into the mud and swooped my net, successfully capturing the cranefly. Back in the lab the next day, I found that the phantom crane fly revived even faster than the ailanthus webworm moth, seeming to regain full movement within moments of exiting the refrigerator. I snapped pictures using a lens that attaches to my phone, but just as I was about to return it to its container to release it, it drifted into the air, and—like a phantom—it disappeared. I never found it again.
A phantom crane fly, which revived almost instantly despite repeated refrigerations.
Duke does not assign an Ethical Inquiry code to the entomology class, but I feel I have done more ethical inquiry in this class than any other. Is photography a worthy reason to risk an insect’s life? Is accidentally releasing a phantom crane fly in a dark room without food or water any better than killing it outright? Is killing insects an essential part of entomology? If so, when is it justified, and when is it not?
In class, we have learned about a series of groundbreaking experiments that strike me as twisted. In one, Stefan Kopec “ligated” caterpillars by tying a very tight string around them to see if either half would still molt. Spoiler: yes, the front half containing the brain. If you cut the brain out of the head and transplant it to the abdomen, then the back half will molt instead. Conclusion: the brain is essential for molting, but it doesn’t need to be attached to the rest of the nervous system. Another experiment involved scientists cutting cecropia moth cocoons in half with a razor blade and sealing each half with wax, followed by more brain transplantation (in this case, a transplanted brain does not make the back half emerge from the cocoon—unless you also transplant a piece of the thoracic gland). Yet another involved beheading two insects and attaching their necks with a capillary tube to see if injecting a hormone into one will prompt the other to molt as well (yes, it will). I hate even imagining these experiments, and I can’t picture myself ever performing them.
My apparent inability to kill insects even in the name of science might become a real problem if I want to study entomology after college. But when I question the value of certain experiments or feel guilty for refrigerating an insect, I am not acting as a scientist. I am acting as an older version of the fourth grader who watched in distress as her classmate ripped caterpillars’ heads off or the eighth grader staring at a circle of kids surrounding a beautiful cecropia moth, distraught from just imagining that someone might hurt it. (The moth was fine—the teacher got one of the kids to agree to protect it. I was not—she sent me to the bathroom to calm down and then sent my friend to check on me.)
At times, I take this concern for the hypothetical suffering of other beings entirely too far. In a cell biology lab this semester, our TA explained that the E. coli bacteria we were working with had had a very rough day: they’d gone through a process that left holes in their membrane, then been put on ice to prevent those holes from completely destroying them. Clearly feeling bad for bacteria is not a recipe for success, but wanting to minimize insects’ suffering seems more justifiable. There seems to be an important distinction between a child pulling caterpillars’ heads off for fun and a scientist tying strings around a caterpillar to answer specific scientific questions. But is the pursuit of knowledge alone enough of a justification for killing the creatures we study? I would have an easier time justifying an experiment that kills insects to advance human medicine or insect conservation.
Ultimately, the morality of killing insects may depend on a question we can never answer: “What does it feel like to be an insect?” I would not want to be shut in a refrigerator for several hours, prodded with a pin, or cut in half with a razor blade, so how can I justify doing that to an insect? I torture myself repeatedly with these thought experiments, but there is a glaring problem with my “golden rule” line of reasoning: I am not an insect. How can I imagine how refrigeration feels to a creature that can slow its metabolism to just 1%, as we learned in class? Perhaps my mom is right when she encourages me to think of these insect-chilling sessions as akin to medically induced comas or periods of peaceful rest rather than sustained torture sessions.
A lacewing in the refrigerator. Since it kept trying to fly away when I took it out, I stuck my head in the refrigerator to take pictures, and the lacewing and I seemed to reach a detente. Later that evening, before it got cold like a refrigerator outside, I let it go.
Where is the line between science and torture? On the flip side, where is the line between anthropomorphizing animals (problematic in science) and giving them the benefit of the doubt when it comes to sentience and capacity to feel pain? It’s not just our experience of the world, our umwelt, that is different from that of insects. We also have entirely different survival strategies. Humans are a K-selected species; we have few offspring but invest heavily into the survival of each individual. Insects, meanwhile, are r-selected; they have many babies, often hundreds or thousands, and many of them will die. If one lace bug can lay hundreds of eggs and many butterflies and moths live only a matter of days, then killing or saving a few insects probably has a negligible impact on the species as a whole. There are other initiatives, like reducing pesticide use, planting native flowers, and mowing lawns less frequently, that can benefit insects on a much larger scale. But the time and effort I spend keeping my refrigerated insects alive was never about protecting a species. It has always been about protecting an individual.
A particularly tiny insect, viewed under a microscope next to part of a pin.
At first, my tendency to get attached to insects made it very difficult for me to justify refrigerating them. But seeing tiny creatures under a microscope is a powerful, intoxicating thrill. Maybe refrigeration is a fair compromise, a way to observe insects without killing them and to keep them safe until I let them go.
A previously refrigerated beetle about to be released back at the Duke Pond.
As a woman, I am familiar with the gynecologist. In fact, thinking about it right now, I may need to create an appointment for one soon. However, I am not just a woman; I am a black woman, and in addition to being familiar with what the gynecologist is, I am also familiar with the dangers of the gynecologist. I know that if I were to become pregnant, I would be three times more likely to die by pregnancy-related causes compared with my white counterparts. This phenomenon is not new; in fact, it is a symptom of the racism within American Gynecology. The founding of this system is not pretty, or pure; it is ugly and distasteful, and during her lecture, historian Deirdre Cooper Owens explains it perfectly.
Dr. Deirdre Cooper Owens and I after her wonderful lecture
Cooper Owens is an associate professor of History and African studies at the University of Connecticut, and earlier this semester, she gave an insightful talk on how slavery and modern American gynecology are interconnected.
The controversial “father of gynecology” was J. Marion Sims, who experimented on enslaved women in Alabama. When talking about the racism in gynecology today and in the past, Sims mainly gets the blunt end of the stick. However, it was not just Sims; it was much bigger than him, Cooper Owens said.
Dr. Samual Cartwright was the first doctor for the Confederacy. Through his experiences with enslaved people, he believed that black people did not feel pain. Furthermore, he created a theory that if an enslaved person ran away or thought about running away, then they had a mental illness. Through the use of a spirometer (a medical tool still used today), he noted that black people have smaller lung capacity than white people. His findings were used to prove that there was a biological difference between races, which is not true.
This idea separated people and placed them in a hierarchy where white people were perceived as superior and black people inferior. The thought of this is damaging in itself, but back then, and sometimes now, they used this ideology as an excuse for the pain they caused African Americans.
Ephriam McDowell, for instance, removed a tumor from the ovaries of a white woman. From this, he then decided to “perfect” this surgery on five black women; four were enslaved, and one was freed. From this group, one person died, and other than that, there is no record of the women’s personal lives.
Dr. Francis M Prevost performed C-sections on enslaved people. These experiments did not take the pain of these women into account; due to the fact that he believed black people did not feel pain, but they did and still do. Now one would hope that a black woman’s relationship with C-sections has improved, but, from 1832 until two years ago, Louisiana was the state where a black woman’s body was used the most for a C-section. Today, that state is Mississippi.
John Peter Mettauer performed experiments on a white woman and a black woman. After the experiment, he claimed that the white woman was cured, but the black woman was not. As a result, he operated on the black woman eight times and claimed that if she did not have intercourse, she would have been cured. However, he failed to take into account that the woman was enslaved and had no control of her body autonomy. So how could she say no to both unwanted sexual encounters and to him?
Lastly, there is James Marion Sims, who is notorious for his contributions to American gynecology. However, such contributions were based on the bodies of enslaved women who had no choice. He used these experiments to advance his techniques and deepen his understanding of gynecology. In fact, it even went to the point where he built a hospital for the sole purpose of experimenting on enslaved women.
J. Marion Sims with his assistants and the victims of his experiments
While the acts and experiments that these men conducted were atrocious, they raised a question for me, why black women? At that time, black people were viewed as an inferior race; they were not equal in physical components and intelligence compared to white people. Therefore, if they are genetically different, why experiment with black women to find cures for white women? When asking that question, the answer is obvious; they knew there was no difference, so they chose to ignore it. They chose to continuously bring harm to these women, and until recently, they were rewarded for it.
Image provided by Harvard T.H. Chan School of Public Health
I learned a lot from this lecture, but if I had to choose only one thing that stuck with me, it would be that the victims of these heinous acts were only referred to as enslaved persons with no name and no story. The only story that was told was the point of view of those committing the acts.
I hope one day, the mortality rate of black women giving birth will decrease to the point that it is simply unheard of. Still, for society and our health system to reach that point, we must understand American gynecology’s true history.
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
What brings seniors Deney Li and Amber Fu together? Aside from a penchant for photoshoots (keep scrolling) and neurobiology, both of them are student research assistants at the lab of Dr. Andrew West, which is researching the mechanisms underlying Parkinson’s in order to develop therapeutics to block disease progression. Ahead lie insights on their lab work, their lab camaraderie, and even some wisdom on life.
(Interview edited for clarity. Author notes in italics.)
What are you guys studying here at Duke? What brought you to the West lab?
DL: I am a biology and psychology double major, with a pharmacology concentration. I started working at a lab spring semester of freshman year that focused on microbial and environmental science, but that made me realize that microbiology wasn’t really for me. I’ve always known I wanted to try something in pharmaceutics and translational medicine, so I transitioned to a new lab in the middle of COVID, which was the West lab. The focus of the West lab is neurobiology and neuropharmacology, and looking back it feels like fate that my interests lined up so well!
Deney Li
AF: I am majoring in neuroscience with minors in philosophy and chemistry, on the pre-med track. I knew I wanted to get into research at Duke because I had done research in high school and liked it. I started at the same time as Deney – we individually cold-emailed at the same time too, in the fall! I was always interested in neuroscience but wasn’t pre-med at the time. A friend in club basketball said her lab was looking for people, and the lab was focused on neurobiology – which ended up being the West lab!
Amber Fu
What projects are you working on in lab?
DL: My work mainly involves immunoassays that test for Parkinson’s biomarkers. My postdoc is Yuan Yuan, and we’re looking at four drugs that are kinase inhibitors (kinases are enzymes that phosphorylate other proteins in the body, which turns them either on or off). We administer these drugs to mice and rats, and look at LRRK2, Rab10 and phosphorylated Rab10 protein levels in serum at different time points after administration.These protein levels are important and indicative because more progressive forms of Parkinson’s are related to higher levels of these proteins.
AF: For the past couple of years, I’ve been working under Zhiyong Liu (a postdoc in the lab). There are multiple factors affecting Parkinson’s, and different labs ones study different factors. The West lab largely studies genetic factors, but what we’re doing is unique for the lab. There’s been a lot of research on how nanoplastics can go past the blood-brain barrier, so we are studying how this relates to mechanisms involved in Parkinson’s disease. Nanoplastics can catalyze alpha-synuclein aggregation, which is a hallmark of the disease. Specifically, my project is trying to make our own polystyrene nanoplastics that are realistic to inject into animal models.
What I’m doing is totally different from Deney – I’m studying the mechanisms surrounding Parkinson’s, Deney is more about drug and treatments – but that’s what’s cool about this lab – there are so many different people, all studying different things but coming together to elucidate Parkinson’s.
Another important project
How much time do you spend in lab?
DL: I’m in lab Mondays, Wednesdays, and Fridays from 9 to 6. All my classes are on Tuesdays and Thursdays!
AF: I’m usually in lab Tuesdays and Thursdays from 12 to 4, Fridays from 9 to 11:45, and then whenever else I need to be.
Describe lab life in three words:
DL: Unexpected growth (can I just do two)?
AF: Rewarding, stimulating, eye-opening.
Lab life also entails goats and pumpkins
What’s one thing you like about lab work and one thing you hate?
DL: What I like about lab work is being able to trouble-shoot because it’s so satisfying. If I’m working on a big project, and a problem comes up, that forces me to be flexible and think on my toes. I have to utilize all the soft skills and thinking capabilities I’ve acquired in my 21 years of life and then apply them to what’s happening to the project. The adrenaline rush is fun! Something I don’t like is that there’s lots of uncertainty when it comes to lab work. It’s frustrating to not be able to solve all problems.
AF: I like how I’ve been able to learn so many technical skills, like cryosectioning. At first you think they’re repetitive, but they’re essential to doing experiments. A process may look easy, but there are technical things like how you hold your hand when you pipette that can make a difference in your results. Something I don’t like is how science can sometimes become people-centric and not focused on the quality of research. A lab is like a business – you have to be making money, getting your grants in – and while that’s life it’s also frustrating.
What do you want to do in the future post-Duke? How has research informed that?
DL: I want to do a Ph.D. in neuropharmacology. I’m really interested in research on neurodegeneration but also have been reading a lot about addiction. So I’ll either apply to graduate school this year or next year. My ultimate goal would be to get into the biotech startup sphere, but that’s more of a 30-years-down-the-road goal! Being in this lab has taught me a lot about the pros and cons of research, which I’m thankful for. Lab contradicts with my personality in some ways– I’m very spontaneous and flexible, but lab requires a schedule and regularity, and I like the fact that I’ve grown because of that.
AF: The future is so uncertain! I am currently pre-med, but want to take gap years, and I’m not quite sure what I want to do with them. Best case scenario is I go to London and study bioethics and the philosophy of medicine, which are two things I’m really interested in. They both influence how I think about science, medicine, and research in general. After medical school, though, I have been thinking a lot about doing palliative care. So if London doesn’t work out, I want to maybe work in hospice, and definitely wouldn’t be opposed to doing more research – but eventually, medical school.
What’s one thing about yourself right now that your younger, first-year self would be surprised to know?
DL: How well I take care of myself. I usually sleep eight hours a day, wake up to meditate in the mornings most days, listen to my podcasts… freshman-year-Deney survived on two hours of sleep and Redbull.
AF: Freshman year I had tons of expectations for myself and met them, and now I’m meeting my expectations less and less. Maybe that’s because I’m pushing myself in my expectations, or maybe because I’ve learned not to push myself that much in achieving them. I don’t necessarily sleep eight hours and meditate, but I am a little nicer to myself than I used to be, although I’m still working on it. Also, I didn’t face big failures before freshman year, but I’ve faced more now, and life is still okay. I’ve learned to believe that things work out.
Jason Dinh’s research career began unintentionally with a semester at Duke’s Marine Lab. A current fourth-year PhD candidate in Duke’s Biology Department, Dinh ventured to the Marine Lab for a mental reset in the spring of his sophomore year as a Duke undergraduate. “While I was there, I realized that people can just get paid to ask questions about how the world works,” Dinh told me, “And I really didn’t know that was a thing that you could do.” Maybe this is what I want to do, he thought.
Jason Dinh, fourth-year PhD candidate in Duke Biology Department
Dinh spent his remaining undergraduate summers investigating the impacts of soundscapes on oyster and fish larvae development. Now, he studies snapping shrimp – a small oceanic species that is “one of the biggest sound producers in the ocean,” bested only by toothed whales.
Dinh first became aware of snapping shrimp during his undergraduate research. He told me that you can find snapping shrimp “basically anywhere, from the equator up to Virginia or maybe North Carolina.” While conducting research on ocean sounds and oyster and fish larvae, Dinh noticed the frequent snapping sounds of the snapping shrimp when he placed underwater microphones. “We didn’t really know what they were doing,” Dinh said.
An image of a species of snapping shrimp like Dinh works with.
The male snapping shrimp is asymmetrical with one very large claw and one that is regular-sized. The large claw has a tiny hook on the end and when the shrimp clamps down or “snaps” the claw, the top half latches into the bottom, shooting out an air bubble at sixty miles per hour that “essentially boils the water behind it,” producing the loud snapping noise in its wake. When many shrimp are snapping at once, it sounds almost like the frying grease when cooking bacon, Dinh tells me. (Click here to watch a video of the snapping shrimp in action.)
At first, researchers suspected the bubble from the snap was a means of stunning prey, but “It turns out that snapping shrimp also fight each other,” Dinh said. And when fighting, male snapping shrimp shoot the air bubbles at one another. The bigger the shrimp’s body size, the larger the snapping claw and the louder the snapping sound.
An image of two snapping shrimp facing off.
Going into his PhD, Dinh wanted to continue his undergraduate work in acoustics and figure out novel ways animals were producing sounds. His investigation of the snapping shrimp took him in new directions, however. Through his projects, Dinh has conducted work on the costs and benefits that keep the claw size as an honest indicator of shrimp size in competitions and approached a plethora of questions from the physiological and physical mechanisms of sending and assessing snaps, up to the evolutionary implications of the sexual selection for claw size.
“I don’t think I really knew I wanted to do research until right before I applied for grad school,” Dinh said at the beginning of our conversation. He remembers being a child curious about nature and bringing in “hundreds of cicadas” and “random critters into the house.” A few decades later and his research is centered on living creatures, which is both a rewarding and tricky process.
“Live animals are going to do what live animals want to do,” Dinh stated simply. “One thing my advisor always tells us is that you don’t get to tell the animal what to do, it tells you what you are going to do.” This has certainly held true for Dinh. While he has had many detailed and well-planned experimental ideas, he says he’s ultimately ended up doing what the “animals told him they were willing and happy to do in the lab.” However, along the way Dinh basks in the “joys in tiny discoveries in the process of research.”
I asked Dinh how he ended up at Duke in the first place and why he chose to stick around for his PhD. “So I ended up at Duke for undergrad because I really liked basketball, which is a really bad reason to choose a school.” But ultimately, this choice “paid off really well because my first year was the last year we won the National Championship,” Dinh said. He traveled to Indianapolis for the event which he says was the “best basketball game of [his] life.”
Dinh decided to do his PhD at Duke because of how deeply he admires his advisor, Sheila Patek (PhD), as a scientist. “I think she’s just a wonderful, passionate, passionate defender of basic science and just doing science because more knowledge is good for society,” Dinh elaborated, “Sheila’s also a staunch and fearless advocate for her students.” Though Dinh considers himself an “outlier” in the lab – primarily a behavioral ecologist in a lab of researchers investigating biomechanics – the way that Patek approaches science is the way that he wants to approach science as well.
Like Alice falling down the rabbit hole in Alice in Wonderland, Dinh compares the diving explorations of science as being a “professional rabbit holer.” Science consists of picking questions further and further apart and leaning into research findings to tunnel into topics.
“I feel like science is being a professional rabbit holer,” Dinh stated. While Dinh is on the pursuit of the weapon size and fighting strategies of snapping shrimp, he doesn’t know exactly where he wants to head next, following the completion of his PhD. Like the snapping shrimp that collect information about their opponents to make an informed decision about engaging in fights, Dinh says he is conducting a sort of Bayesian method of his own. He’s assessing his experiences as he goes and sorting out the right next step for him.
A fan of the meditative art of writing, long morning walks with his dog, and reality TV, Dinh appreciates being “on the frontier of what we know” and is sure to let his deep-rooted curiosity about the natural world continue to guide him.
It’s common for a Pratt engineering student like me to be surrounded by incredible individuals who work hard on their revolutionary projects. I am always in awe when I speak to my peers about their designs and processes.
So, I couldn’t help but talk to sophomore Joanna Peng about her project: LowCostomy.
Rising from the EGR101 class during her freshman year, the project is about building a low-cost colostomy bag — a device that collects excrement outside the patient after they’ve had their colon removed in surgery. Her device is intended for use in under-resourced Sub-Saharan Africa.
“The rates in colorectal cancer are rising in Africa, making this a global health issue,” Peng says. “This is a project to promote health care equality.”
The solution? Multiple plastic bags with recycled cloth and water bottles attached, and a beeswax buffer.
“We had to meet two criteria: it had to be low cost; our max being five cents. And the second criteria was that it had to be environmentally friendly. We decided to make this bag out of recycled materials,” Peng says.
For now, the team’s device has succeeded in all of their testing phases. From using their professor’s dog feces for odor testing, to running around Duke with the device wrapped around them for stability testing, the team now look forward to improving their device and testing procedures.
“We are now looking into clinical testing with the beeswax buffer to see whether or not it truly is comfortable and doesn’t cause other health problems,” Peng explains.
Poster with details of the team’s testing and procedures
Peng’s group have worked long hours on their design, which didn’t go unnoticed by the National Institutes of Health (NIH). Out of the five prizes they give to university students to continue their research, the NIH awarded Peng and her peers a $15,000 prize for cancer device building. She is planning to use the money on clinical testing to take a step closer to their goal of bringing their device to Africa.
Peng shows an example of the beeswax port buffer (above). The design team of Amy Guan, Alanna Manfredini, Joanna Peng, and Darienne Rogers (L-R).
“All of us are still fiercely passionate about this project, so I’m excited,” Peng says. “There have been very few teams that have gotten this far, so we are in this no-man’s land where we are on our own.”
She and her team continue with their research in their EGR102 class, working diligently so that their ideas can become a reality and help those in need.
Clara Howell and I meet to chat on a lovely October afternoon under the trees of the Bryan Center Plaza. In my final Fall at Duke as an undergraduate, I am happy to connect with Clara, a third-year PhD student in the biology department. We meet on the auspices that I want to learn more about her trek through academia and her current work in the Nowicki lab for this very profile piece. “I’ve never been written about before,” Clara says to me. I suspect that, though most grad students’ work is totally cool, most of them never have.
Clara Howell, Ph.D. student, conducting field work.
Clara talks with her hands as she lays out her current work for me. Right now, she is studying sexual selection and infection in different bird species. Duke biology professor Steve Nowicki, one of Clara’s advisors, has done a lot of work on honesty in communication systems between animals. Most species, Clara tells me, rely on honest signals for mate choice, because it benefits females to be able to discern between low- and high-quality mates, and it benefits high quality males to be able to advertise their quality. In general, animal signals should be reliable. Clara’s other advisor, biology professor and chair of evolutionary anthropology Susan Alberts, specializes in life history trade-offs of signaling: Animals only have so many resources and they must make choices about how to use them. A male bird, that is, for example, fighting an infection, cannot devote as many resources to sexual signaling as an uninfected male.
“But,” Clara says, with an increasingly bright smile on her face, “There is an interesting period of time right after an animal is exposed to a potential pathogen where it’s not immediately clear if the bird’s sexual signals will be honest. This is because it could be most advantageous for animals – especially males – to continue devoting every resource possible for sexual signaling, even if it means ignoring a pathogen that will eventually kill them.”
The punchline is, the male swamp sparrows and zebra finches that Clara studies might benefit from “lying” about being sick. By ignoring an arising infection and devoting one’s energy to maintaining strong sexual signaling, these male birds may be tricking females into thinking they are perfectly healthy mates with no sickness in sight. So far, Clara has been recording the songs of male birds following an injection of bacterial cell walls to stimulate their immune response. “The real kicker will be when I test females and see how and if they discern between the songs of sick and healthy males.”
Zebra Finch (left) and Swamp Sparrow (right)
“When we started to social distance at the beginning of the pandemic in March 2020, before any of us knew how long this would last, I wondered whether other animals do the same thing,” Clara said. When COVID-19 put a pause to Clara’s original work, she found inspiration in the pandemic itself to think about cues of sickness in other animal species besides our own – an idea she saw other scientists starting to buzz about.
Before grad school, Clara studied neuroscience and English at Tulane University in New Orleans. She worked in an evolutionary biology lab with former Duke Ph.D. Elizabeth Derryberry beginning in sophomore year and did her honor’s thesis in Derryberry’s lab on connections between novel foraging tasks and mate preferences in zebra finches. And Clara loved her advisor so much that she decided to follow Derryberry to the University of Tennessee as a grad student in the same year she earned her bachelor’s degree.
“What about your English major?” I asked Clara. “I was a very nerdy, book-ish child,” she replied, “I wanted to read more in college.” Her background in English has turned out to be quite useful for her work in the sciences. “Having really great scientific ideas and not being able to tell people about them is pretty useless,” she said with a short laugh. These English skills have been useful for grant writing too. That’s right – I asked Clara to tell me about the less glamorous parts of being a grad student.
“The process of finding money is something I wish people talked about more,” Clara said as she wrapped her long ponytail through her hands. The through line: “If you want to do your own ideas, you have to find your own money,” she stated plainly. The process of finding money takes up a considerable amount of her time and most grants she has applied for she does not end up getting. But because she enjoys writing, she says it’s not so bad. Though Clara wishes departments were more open about research funding policies and that there were more internal grants, she’s never thought of grant writing as a waste of time. “A lot of the time when I write grants, I’m really clarifying ideas. It’s definitely helpful,” she tells me.
Grant writing takes up a considerable amount of time for most science Ph.D. students.
Clara’s advice to anyone interested in a science Ph.D. is to truly consider getting a master’s degree beforehand. “It might not be the right choice for everyone,” Clara said, “But I found the transition from undergrad to graduate school really difficult. I spent most of my master’s degree just learning how to be a grad student and figuring out how academia works, which meant that when I started my Ph.D. I could focus much more on what I wanted to research.” The time in her master’s program also helped her home in on her central interests in biology. And oh, she also recommends noise-canceling headphones, her “favorite possession.”
Although she says she is still working on figuring out her work-life balance, Clara likes being able to set her own schedule and how each week is so different from the next. Outside of lab, Clara claims she is the stereotype of ecology and evolutionary biology grad students: She enjoys rock-climbing, board games, and craft breweries. You might have to go to the Biological Sciences building to find Clara. “I haven’t broached the other areas of campus,” she said, “Undergrads are sort of scary. They use language I don’t understand, and they are all so stylish. They make me feel old.” Old at 26, the life of the biology Ph.D.
A blue whale skeleton suspended in London’s Natural History Museum
Odd skulls are nothing new to V. Louise Roth, a professor in the Department of Biology. Much of her research centers on how animals’ shapes and sizes evolve and develop, so weirdly shaped bones are at the core of her work. But when Ph.D. student Rachel Roston drew her attention to the peculiarities of whale skulls, even Roth was astounded.
“There are some pretty weird mammal skulls out there,” Roth said. “I have studied morphological development in elephants, which are also kind of a crazy choice, but in terms of which bone goes where I think cetaceans are the weirdest ones.”
Cetaceans are the group that includes baleen whales – such as humpback whales – and toothed whales – such as dolphins and killer whales. Unlike almost all other vertebrate animals, cetaceans don’t breathe out of their mouths or from a nose placed in front of their face, but from a blowhole located on top of their head.
How did it get up there?
Rachel Roston, a graduate student in the Duke Biology department, recently published a paper with Professor Louise Roth, about some of the ways dolphin, whale and porpoise skulls break the rules of anatomy.
A new study published in the Journal of Anatomy by Roth and Roston, now a postdoctoral researcher at the University of Washington, reveals how whale and dolphin skulls undergo a complete transformation through their embryonic and fetal development, resulting in a re-orientation of their nasal passages.
What’s more, there’s not just one way to do it: baleen whales and toothed whales move their nostrils to the tops of their heads in two very different ways.
“It’s not just that they are developing the same thing in different ways,” said Roston, who led this work as part of her Ph.D. in Biology at Duke. “Looking from the outside of the body all you see is that both of them have their nose on the top of their head, but when you look inside their skulls, they are actually totally different blowholes.”
A toothed whale clears its blowhole. Photo by Friedrich Frühling
To figure out which bone went where and in which way, Roston looked at CT scans of baleen and toothed whales’ embryos in different stages of development and drew a dotted timeline of anatomical changes through the animals’ development.
Early-stage embryos look very much alike in most vertebrate animals: small, with a disproportionally large head, big eyes and oral and nasal cavities in the front of their face. As the embryos develop, they take different paths and become more and more similar to their own species.
Most of them keep their noses and their mouths in front of their face, but dolphins and whales transform their whole heads to change the direction of their nasal passage while keeping the snout facing forward.
“We think of the nostrils as something you find at the tip of the snout,” Roth said. “But whales go through some key changes in bone orientation that decouple one from the other.”
“It’s like looking at a cubist Picasso painting,” Roston said. “The eyes, nose and mouth are all there, but their relationships to each other are completely distorted.”
Whale embryos at different developmental stages. The white arrow shows how the nasal cavity shifts position through embryonic development.
This internal shuffling requires that the parts forming the roof of the embryo’s mouth move away from those that form its nasal passage. Initially parallel in small young embryos, they end up at an angle of about 45 degrees in baleen whales. In toothed whales this final angle is even wider, closer to 90 degrees.
In baleen whales, a key rotation happens at the back of the skull, where it meets the spine. Rather than being perpendicular to the ground, as in the head of a dog, the back of the skull is tilted forward towards the snout.
In toothed whales, the point of inflexion for this rotation is in the middle of the head. A bone in the center of the skull changes shape, curving upwards as the nasal passage ends facing up.
Roston and Roth both say that museum collections and non-destructive scanning techniques, such as CT scans, were key for this project because whale embryo specimens are difficult to come by. When a gravid female dies, small embryos often go unnoticed in their mother’s massive carcass. But older fetuses are larger than your typical sedan, making them difficult to preserve intact and store in museums. The few specimens found in museums must therefore be studied with the proverbial velvet gloves, or, in this case, CT scans.
“In science you always question ‘how come no one’s done this before?’” Roston said. “Here, it was because specimens are precious, so you don’t want to cut them up and destroy them.”
“Sometimes we’re looking at museum specimens that are 100 years old. This was an opportunity to describe them in a way that I hope will still be useful 100 years from now.”
The research was funded by Duke University. Roston has also been supported by the National Institutes of Health.
CITATION: “Different Transformations Underlie Blowhole and Nasal Passage Development in a Toothed Whale (Odontoceti: Stenella attenuata) and a Baleen Whale (Mysticeti: Balaenoptera physalus),” Rachel A. Roston, V. Louise Roth, Journal of Anatomy. DOI: 10.1111/joa.13492
Odd skulls are nothing new to 
