Biology Archives - Page 10 of 32

“I don’t believe that [going to] Mars pushes us hard enough.” This was just one of the bold, thought-provoking statements made by Dr. Mae Jemison, who came to speak at Duke on Monday, February 24 as part of the 15th annual Jean Fox O’Barr Distinguished Speaker Series, presented by Baldwin Scholars.

Dr. Jemison is at the pinnacle of interdisciplinary engagement—though she is most famous for serving as a NASA astronaut and being the first African American woman to go into space, she is also trained as an engineer, social scientist and dancer. Dr. Jemison always knew that she was going to space—even though there were no women or people or color participating in space exploration as she was growing up.

Dr. Jemison says that simply “looking up” brought her here. As a child, she would look up at the sky, see the stars and wonder if other children in other places in the world were looking at the same view that she had. Growing up in the 1960’s instilled into Dr. Jemison at an early age that our potential is limitless, and the political culture of civil rights, changing art and music and decolonization were all about “people declaring that they had a right to participate.”

One of the biggest pieces of advice that Dr. Jemison wanted to impart on her audience was the value of confidence, and how to build confidence in situations where people are tempted to feel incapable or forget the strengths they already possess. “They told me if I wanted to lead projects I needed an M.D.,” Dr. Jemison explained. “I went to medical school because I know myself and I knew I would want to be in charge one day.”

At 26 years old, Dr. Jemison was on call 24 hours a day, 7 days a week, 365 days a year as the Area Peace Corps Medical Officer for Sierra Leone and Liberia. She described a case where a man came back with a diagnosis of malaria from Senegal. When Dr. Jemison first took a look, the diagnosis seemed more likely to be meningitis. After making an “antibiotic cocktail,” from what she had on site, she realized this man might lose his life if they didn’t get him to a better hospital. At this point, Dr. Jemison wanted to call a military medical evacuation, and she had the authority to do it. However, another man working with her suggested calling a doctor in Ivory Coast, or a doctor at the hospital in Germany to see what he thought before making the evacuation. Dr. Jemison knew what the patient needed in this situation was to be flown to Germany regardless of the cost of the evacuation. In reflecting on this experience, she says that she could have given someone else her authority, but letting her confidence in herself and what she knew was the right thing to do would have negatively impacted her patient.

So, how do you maintain confidence? According to Dr. Jemison, you come prepared. She knew her job was to save people’s lives, not to listen to someone else. Dr. Jemison also admonished the audience to “value, corral and protect your energy.” She couldn’t afford to always make herself available for non-emergency situations, because she needed her energy for when a patient’s life would depend on it.

Dr. Jemison’s current project, 100 Year Starship, is about trying to ensure we have the capabilities to travel to interstellar space. “The extreme nature of interstellar hurdles requires we re-evaluate what we think we know,” Dr. Jemison explained. Alpha Centauri, the next closest star, is more than 25 trillion miles away. Even if we go 10% the speed of light, it will still take us 50 years to get there. We need to be able to travel faster, the vehicle has to be self-replenishing, and we have to think about space-time changes. What Dr. Jemison calls the “long pole in the tent” is human behavior. We need to know how humans will act and interact in a small spaceship setting for possibly decades of space travel. Dr. Jemison is thinking deeply about how we can apply the knowledge we already possess to fix world problems, and how we can start preparing now for problems we may face in the future. For example, how would health infrastructure in deep space look different? How would we act on a starship that contains 5,000 people when we can’t figure out how to interact with each other on the “starship” we’re on now?

Returning to the childhood love for stargazing that brought her here, Dr. Jemison discussed towards the end of her talk that a stumbling block for the majority of people is insufficient appreciation of our connection across time and space. She has worked with a team to develop Skyfie, an app that allows you to upload photos and videos of your sky to the Sky Tapestry and explore images other people in different parts of the world are posting of their sky. Dr. Jemison’s hope is this app will help people realize that we are interconnected with the rest of the universe, and we won’t be able to figure out how to survive as a species on this planet alone.

By Victoria Priester

#UniqueScientists Is Challenging Stereotypes About Who Becomes a Scientist

By Irene Park

On February 24, 2020

In Behavior/Psychology, Biology, Immunology, Science Communication & Education

University of North Carolina cell biologist Efra Rivera-Serrano says he doesn’t look like a stereotypical scientist: he’s gay, Puerto Rican, and a personal trainer.

Known on Twitter as @NakedCapsid or “the guy who looks totally buff & posts microscopy threads,” he tweets about virology and cell biology and aims to make science more accessible to the non-science public.

But science communication encompasses more than posting the facts of viral transmission or sending virtual valentines featuring virus-infected cells, Rivera-Serrano says. As a science communicator, he’s also committed to conveying truths that are even more rarely expressed in the science world today. He’s committed to diversity.

Rivera-Serrano’s path through academia has been far from linear — largely because of the microaggressions (which are sometimes not so micro) that he’s faced within educational institutions. He’s been approached while shopping by a construction work recruiter and told by a graduate adviser in biology to “stop talking like a Puerto Rican.”

Efra Rivera-Serrano, Ph.D.
He’s a scientist at UNC—and also a personal trainer.
Photo from @NakedCapsid Twitter

And the worst part is that he’s far from being the only one in this kind of position. That’s why Rivera-Serrano holds one simple question close to heart:

What would a cell do?

“I use this question to shape the way I tackle problems,” Rivera-Serrano says. After all, a key component of virology is the importance of intercellular communication in controlling disease spread. Similarly, a major goal of diversity-related science communication is “priming” others to fight stereotypes and biases about who belongs in science.

Virology’s “herd immunity” theory operates under the principle that higher vaccination rates mean fewer infections. For some viruses, a 90% vaccination rate is all it takes to completely eradicate an infection from existing in a population. Rivera-Serrano, therefore, hopes to use inclusive science communication as a vaccination tool of sorts to combat discriminatory practices and ideologies in science. He isn’t looking for 100% of the world to agree with him—only enough to make it work.

Herd immunity places value on community rather than individuals.
Image by Tkarcher via Wikimedia Commons

This desire for “inclusive science communication” led Rivera-Serrano to found Unique Scientists, a website that showcases and celebrates diverse scientists from across the globe. Scientists from underrepresented backgrounds can submit a biography and photo to the site and have them published for the world’s aspiring scientists to see.

Some Unique Scientists featured on Rivera-Serrano’s site!

Generating social herd immunity needs to start from an early age, and Unique Scientists has proven itself useful for this purpose. Before introducing the website, school teachers asked their students to draw a scientist. “It’s usually a man who’s white with crazy hair,” according to Rivera-Serrano. Then, they were given the same instructions after browsing through the site, and the results were remarkable.

“Having kids understand pronouns or see an African American in ecology—that’s all something you can do,” Rivera-Serrano explains. It doesn’t take an insane amount of effort to tackle this virus.

What it does take, though, is cooperation. “It’s not a one-person job, for sure,” Rivera-Serrano says. But maybe we can get there together.

For Lemurs, Water Holes Are a Matter of Taste

By Guest Post

On February 20, 2020

In Animals, Biology, Field Research, Lemurs

It’s 1 PM and you’re only halfway through a 6-hour hike, climbing in steep terrain under a 100° cloudless sky. Your water bottle is nearly empty, and you’ve heard the worst of this hike is yet to come.

And then, just as you are making peace with the fact that you may collapse from dehydration at any second, you approach a small river. The germaphobe side of your brain is shouting for you not to drink from that. The dehydrated animal in you, however, is seriously considering it.

What do you do?

That is the question that Dr. Caroline Amoroso and her collaborators from Duke’s department of evolutionary anthropology, set out to answer. With a slight difference: rather than unprepared hikers, they asked that question to red-fronted lemurs in Madagascar.

Although we often associate Madagascar with lush forests, some regions have a very marked dry season during which water becomes a limited resource. Water holes are few and far apart.

A red-fronted lemur in Kirindy Forest, Madagascar, tanks up at a watering hole. (Photo: Caroline Amoroso)

“On my first visit to Kirindy forest I was amazed at how these waterholes – which are essentially just puddles of standing water – serve as a source of life for so many animals,” says Amoroso.

However, with animals, comes poop. Throughout the season, these water holes quickly become contaminated with fecal matter from all the mammals, birds and reptiles that come have a drink. Amoroso says that fecal contamination was easily detectable even to human observers. “Approaching some waterholes I could tell that lemurs had been there recently because their droppings left such a smell!”

By experimentally manipulating water quality, following groups of radio-collared lemurs and observing lemur behavior at natural water holes, Amoroso and her team found that, all else being equal, lemurs prefer to drink clean water.

Indeed, when offered the choice between a bucket of clean water and a bucket of water containing lemur feces that had been disinfected by boiling, to kill all possible pathogens, lemurs virtually always drank from the clean water bucket. When the buckets were removed and lemurs had to go visit natural water holes, however, they prioritized water holes closer to their resting site, even if they were more contaminated than further ones. Proximity was more important than cleanliness, but if multiple water holes were at similar distances, then lemurs seem to choose the least-contaminated source.

“I was surprised to find evidence that the lemurs chose natural waterholes with lower levels of fecal contamination,” says Amoroso. “I thought that [in a natural setting] avoidance of fecal contamination would be relatively low on the lemurs’ list of priorities.”

After some watchful waiting for predators, and a discussion perhaps, a quartet of Kirindy lemurs visits a tiny watering hole. (Photo: Caroline Amoroso)

The authors highlight that many other factors can influence a lemur’s choice of water hole, such as exposure to potential predators or visits by competing groups. Indeed, Amoroso says that drinking water can be a very risky business for lemurs: “Lemurs would spend upwards of thirty minutes scanning the vegetation nervously and making sure there was no sign of predators before approaching the waterhole and drinking.”

Lemurs prefer clean water, unless it’s too much trouble. In that hike you were on? Lemurs would definitely drink from the river.

Guest Post by Marie Claire Chelini, a postdoctoral fellow in evolutionary anthropology.

The evolution of a tumor

By Sarah Haurin

On January 23, 2020

In Biology, Cancer, Genetics/Genomics, Lecture, Mathematics, Medicine

The results of evolution are often awe-inspiring — from the long neck of the giraffe to the majestic colors of a peacock — but evolution does not always create structures of function and beauty.

In the case of cancer, the growth of a population of malignant cells from a single cell reflects a process of evolution too, but with much more harrowing results.

Johannes Reiter uses mathematical models to understand the evolution of cancer

Researchers like Johannes Reiter, PhD, of Stanford University’s Translational Cancer Evolution Laboratory, are examining the path of cancer from a single sell to many metastatic tumors. By using this perspective and simple mathematical models, Reiter interrogates the current practices in cancer treatment. He spoke at Duke’s mathematical biology seminar on Jan. 17.

The evolutionary process of cancer begins with a single cell. At each division, a cell acquires a few mutations to its genetic code, most of which are inconsequential. However, if the mutations occur in certain genes called driver genes, the cell lineage can follow a different path of rapid growth. If these mutations can survive, cells continue to divide at a rate faster than normal, and the result is a tumor.

As cells divide, they acquire mutations that can drive abnormal growth and form tumors. Tumors and their metastases can consist of diverse cell populations, complicating treatment plans out patient outcomes. *Image courtesy of Reiter Lab*

With each additional division, the cell continues to acquire mutations. The result is that a single tumor can consist of a variety of unique cell populations; this diversity is called intratumoral heterogeneity (ITH). As tumors metastasize, or spread to other locations throughout the body, the possibility for diversity grows.

Intratumoral heterogeneity can exist within primary tumors, within metastases, or between metastases. Vogelstein et al., *Science*, 2013

Reiter describes three flavors of ITH. Intra-primary heterogeneity describes the diversity of cell types within the initial tumor. Intra–metastatic heterogeneity describes the diversity of cell types within a single metastasis. Finally, inter-metastatic heterogeneity describes diversity between metastases from the same primary tumor.

For Reiter, inter-metastatic heterogeneity presents a particularly compelling problem. If treatment plans are made based on biopsy of the primary tumor but the metastases differ from each other and from the primary tumor, the efficacy of treatment will be greatly limited.

With this in mind, Reiter developed a mathematical model to predict whether a cell sample collected by biopsy of just the primary tumor would provide adequate information for treatment.

Using genetic sequence data from patients who had at least two untreated metastases and a primary tumor, Reiter found that metastases and primary tumors overwhelmingly share a single driver gene. Reiter said this confirmed that a biopsy of the primary tumor should be sufficient to plan targeted therapies, because the risk of missing driver genes that are functional in the metastases proved to be negligible.

In his next endeavors as a new member of the Canary Center for Cancer Early Detection, Reiter plans to use his knack for mathematical modeling to tackle problems of identifying cancer while still in its most treatable stage.

Post by undergraduate blogger Sarah Haurin

Post by Sarah Haurin

Flu No More: The Search for a Universal Vaccine

By Jeremy Jacobs

On January 6, 2020

In Biology, Global Health, Immunology

Chances are, you’ve had the flu.

Body aches, chills, congestion, and cough—for millions across the globe, these symptoms are all too familiar.

Dr. Peter Palese, an Icahn School of Medicine researcher working on a universal flu vaccine.

For some, though, the flu leads to serious complications. Last year, as many as 647,000 Americans were hospitalized due to flu-related illness, with an additional 61,000 deaths.

Countless hours of lost productivity also accompany the illness. Including hospitalization costs, estimates for the flu’s total economic burden range from 10 to 25 billion dollars each year.

Flu prevention efforts have yielded mixed results. For many viruses, vaccines provide protection that lasts a lifetime, building up a network of antibodies primed to neutralize future infections. Influenza viruses, however, mutate quickly, rendering vaccines from years past ineffective. As a result, new vaccines are constantly in development.

Every year, researchers predict which flu viruses are likely to dominate the upcoming flu season. Based on these predictions, new vaccines target these specific strains. Consequentially, the effectiveness of these vaccines vary with the prediction. When a vaccine is a good match for the dominant flu strain, it can lower rates of infection by 40-50%. When it isn’t, its preventative power is far lower; in 2014, for example, the yearly influenza vaccine was only 19% effective.

Peter Palese, Ph. D, might have a better solution. Working at the Icahn School of Medicine, Palese and his team are developing a vaccine that takes a new approach to flu prevention.

Just before classes ended last month, Palese spoke at the Duke Influenza Symposium, a showcase of Duke’s current research on influenza. The symposium is part of Duke’s larger push to improve the efficacy of flu vaccination.

Palese’s vaccines work by redirecting the immune response to the influenza virus. Traditional vaccines create antibodies that target hemagglutinins, proteins found on the outermost part of influenza viruses. Hemagglutinins are divided into two regions: a head domain and a stalk domain (Fig. 1).

Fig. 1: Left: General influenza structure. Right: Hemagglutinins are divided into two regions: a head domain and a stalk. The head domain is prone to mutation and undergoes rapid change while the stalk domain is more resistant to mutation.
Source: Frontiers in Immunology

In a traditional vaccination, the head domain is immunodominant—that is, the antibodies produced by vaccines preferentially target and neutralize the head domains. However, the head domain is highly prone to mutation and varies between different strains of influenza. As a result, antibodies for one strain of the virus provide no protection against other strains.

The new vaccines pioneered by Palese and his team instead target the stalk domain, a part of hemagglutinin that mutates far slower than the head domain. The stalk is also conserved across different subtypes of the influenza virus. As a result, these vaccines should theoretically provide long-lasting protection against most strains of influenza.

Testing in ferret, mice, and guinea pigs have produced promising results. And early human trials suggest that this new kind of vaccination grants broad immunity against influenza. But long-term results remain unclear—and more trials are underway. “We would love to say it works,” Palese says. “But give us 10 years.”

In the meantime, the seasonal flu vaccine is our best option.“The recommendation to vaccinate everyone is the right policy,” Palese tells us.

Post by Jeremy Jacobs

Working Through Frustrations to Understand Nature Better

By Guest Post

On December 30, 2019

In Biology, Genetics/Genomics, Medicine

This is the fifth of six posts written by students at the North Carolina School of Science and Math as part of an elective about science communication with Dean Amy Sheck.

Research is a journey full of uncertainty in which scientists have to construct their own path, even if they’re unsure of what the end of the journey actually is. Despite this unpredictability, researchers continue their journey because they believe their work will one day drive their fields forward. At least, that’s why Kate Meyer Ph.D. says she has investigated something called m6A for several years.

“Virtually every study that I have ever been part of had some frustrations involved because everything can fall apart in just one night,” Meyer said. “Despite all the frustrations you might have, you are still in the research because you know that at the end of the day, you will get new knowledge that is worthy to your field, or perhaps to the world.”

N6-methyladenosine (or m6A) is a modification to one of the four main bases of RNA – adenosine. Because RNA plays a significant role as a bridge between genetic information and functional gene products, modifications in RNA can alter how much of a certain product will be produced, which then controls how our cells and eventually our whole body functions.

The idea of this tiny but powerful modification was first proposed in the 1970s. But scientists struggled to find where m6A was located in the cell before research Meyer made a major contribution to as a trainee was published in 2012. Combining a newly developed antibody that could recognize m6A and gene sequencing techniques that became more accessible to the researchers, Meyer’s work led to the first method that can detect and sequence all of the m6A regions in a cell.

m6A’s interaction with a neuron, as depicted on Dr. Meyer’s laboratory site.

Meyer’s work was transformative research. Her method allowed laboratories around the world to investigate what regulates m6A and what its consequences are. Meyer said this first study which ignited m6A field is one of her most prideful moments as a researcher.

Significant progress has been made since 2012, but there are still lots of questions that need to be answered. Currently, Meyer’s research team is investigating the relationships between m6A and various neurological issues. She believes that regulation of m6A controls the expression, or activity level, of various genes in the brain. As such, m6A may play an important role in neurodegenerative diseases and memory.

Author Jun Hee Shin, left, and Kate Meyer in her lab.

As an assistant professor of both biochemistry and neurobiology at Duke, Meyer is definitely one of the most important figures in the m6A field. Despite her many accomplishments, she said she had experienced and overcome many frustrations and failures on her way to the results.

Guest Post by Jun Shin, NCSSM 2020

How Do You Engineer a Microbial Community?

By Guest Post

On December 20, 2019

In Biology, Engineering, Environment/Sustainability, Faculty, Guest Post, Students

This is the first of several posts written by students at the North Carolina School of Science and Math as part of an elective about science communication with Dean Amy Sheck.

Claudia Gunsch, the Theodore Kennedy distinguished associate professor in the department of civil and environmental engineering, wants to know how to engineer a microbial community. An environmental engineer with a fascination for the world at the micro level, Gunsch takes a unique approach to solving the problem of environmental pollution: She looks to what’s already been done by nature.

Gunsch and her team seek to harness the power of microbes to create living communities capable of degrading contamination in the environment.

“How can you engineer that microbial community so the organisms that degrade the pollutant become enriched?” she asks. “Or — if you’re thinking about dangerous pathogenic organisms — how do you engineer the microbial community so that those organisms become depressed in that particular environment?”

The first step, Gunsch says, is to figure out who’s there. What microbes make up a community? How do these organisms function? Who is doing what? Which organisms are interchangeable? Which prefer to live with one another, and which prefer not living with one another?

“Once we can really start building that kind of framework,” she says, “we can start engineering it for our particular purposes.”

Yet identifying the members of a microbial community is far more difficult than it may seem. Shallow databases coupled with vast variations in microbial communities leave Gunsch and her team with quite a challenge. Gunsch, however, remains optimistic.

“The exciting part is that we have all these technologies where we can sequence all these samples,” she says. “As we become more sophisticated and more people do this type of research, we keep feeding all of this data into these databases. Then we will have more information and one day, we’ll be able to go out and take that sample and know exactly who’s there.”

“Right now, it’s in its infancy,” she says with a smile. “But in the long-term, I have no doubt we will get there.”

Gunsch is currently working on Duke’s Superfund Research Center designing bioremediation technologies for the degradation of polycyclic aromatic hydrocarbon (PAH) contamination. These pollutants are extremely difficult to break down due to their tendency to stick strongly onto soil and sediments. Gunsch and her team are searching for the right microbial community to break these compounds down — all by taking advantage of the innate capabilities of these microorganisms.

A photo montage from Dr. Gunsch’s lab page.

Step one, Gunsch says, has already been completed. She and her team have identified several different organisms capable of degrading PAHs. The next step, she explains, is assembling the microbial communities — taking these organisms and getting them to work together, sometimes even across kingdoms of life. Teamwork at the micro level.

The subsequent challenge, then, is figuring out how these organisms will survive and thrive in the environment they’re placed in, and which microbial seeds will best degrade the contamination when placed in the environment. This technique is known as “precision bioremediation” — similar to precision medicine, it involves finding the right solution in the right amounts to be the most effective in a certain scenario.

“In this particular case, we’re trying to figure out what the right cocktail of microbes we can add to an environment that will lead to the end result that is desired — in this case, PAH degradation,” Gunsch says.

Ultimately, the aim is to reduce pollution and restore ecological health to contaminated environments. A lofty goal, but one within sight. Yet Gunsch sees applications beyond work in the environment — all work dealing with microbes, she says, has the potential to be impacted by this research.

“If we understand how these organisms work together,” she says, “then we can advance our understanding of human health microbiomes as well.”

Post by Emily Yang, NCSSM 2021

A Research Tour of Duke’s Largest Lab

By Veronique Koch

On December 12, 2019

In Biology, Climate/Global Change, Data, Environment/Sustainability, Field Research

“Lightning is like a dangerous animal that wants to go places. And you can’t stop it,” smiled Steve Cummer, Ph.D. as he gestured to the colorful image on the widescreen TV he’d set up outside his research trailer in an open field in Duke Forest.

Cummer, the William H. Younger Professor of electrical and computer engineering at Duke, is accustomed to lecturing in front of the students he teaches or his peers at conferences. But on this day, he was showing spectacular videos of lightning to curious members of the public who were given exclusive access to his research site on Eubanks Road in Chapel Hill, about 8 miles west of campus.

Steve Cummer shows a time-lapse video of lightning to the visitors on the annual Duke Forest Research Tour in the Blackwood Division of the Duke Forest.

More than two dozen members of the community had signed up for a tour of research projects in the Blackwood Division of Duke Forest (which recently expanded), a research-only area that is not normally open to the public. Cummer’s research site was the last stop of the afternoon research tour. The tour also covered native trees, moths and geological features of the Blackwood Division with biologist and ecologist Steve Hall, and air quality monitoring and remote sensing studies with John Walker and Dave Williams, from the U.S. Environmental Protection Agency.

The Hardwood Tower in the Blackwood Division is used for air quality monitoring and remote sensing studies. Researchers frequently climb the 138 foot tall tower to sample the air above the tree canopy.

Cummer’s research on lightning and sprites (electrical discharges associated with lightning that occur above thunderstorm clouds) sparked a lively question and answer session about everything from hurricanes to how to survive if you’re caught in a lightning storm. (Contrary to popular belief, crouching where you are is probably not the safest solution, he said. A car is a great hiding spot as long as you don’t touch anything made of metal.)

Cummer kept his tone fun and casual, like a live science television host, perched on the steps of his research trailer, referring to some of the scientific equipment spread out across the field as “salad bowls,” “pizza pans” and “lunar landers,” given their odd shapes. But the research he talked about was serious. Lightning is big business because it can cause billions of dollars in damage and insurance claims every year.

An ash tree (*Fraxinus spp*.) being examined by one of the visitors on the Duke Forest Research tour. Blackwood Division ash trees are showing signs of the highly destructive emerald ash borer invasion.

Surprisingly little is known about lightning, not even how it is first formed. “There are a shocking number of things,” he said, pausing to let his pun sink in, “that we really don’t understand about how lightning works. Starting with the very beginning, nobody knows exactly how it starts. Like, really the physics of that.” But Cummer loves his research and has made some advances in this field (like devising more precise sensor systems), “When you’re the first person to understand something and you haven’t written about it yet or told anyone about it… that’s the best feeling.”

The Duke Forest hosted 49 research projects last year, which —with less than half of the projects reporting—represented over a million dollars of investment in Duke Forest-based work.

“The Duke Forest is more than just a place to walk and to jog. It’s an outdoor classroom. It’s a living laboratory. It’s where faculty and teachers and students of all ages come to learn and explore,” explained Sara Childs, Duke Forest director.

The Duke Forest offers their research tour every year. Members of the public can sign up for the email newsletter to be notified about future events.

Post by Véronique Koch

Stalking Elusive Ferns Down Under

By Guest Post

On November 11, 2019

In Biology, Field Research, Guest Post, Students

Graduate student Karla Sosa (left) photographs and presses newly collected ferns for later analysis while Ashley Field (in truck) marks the GPS location of the find.

In Queensland, Australia, early March can be 96 degrees Fahrenheit. It’s summer in the Southern Hemisphere, but that’s still pretty hot.

Although hot, dry Australia probably isn’t the first place you’d think to look for ferns, that’s precisely why I’m here and the sole reason we’ve hit the road at 6 a.m. Our schedule for the day: to drive as far south as we can while still letting us come home at the end of the day.

My local colleague, Ashley Field, grew up just the next town over. A skinny, speedy man, he works at James Cook University in Cairns and knows most of northern Queensland like the back of his hand.

Cairns is on the coast at the upper right, where the little green airplane is.

The ferns I’m looking for today are interesting because some species can move from their original home in Australia to the tiny islands in the Pacific. But some cannot. Why? Understanding what makes them different could prove useful in making our crops more resilient to harsh weather, or preventing weeds from spreading.

We’ve been driving for four hours before we turn off onto a dirt road. If you haven’t been to Australia, it’s worth noting that four hours here is unlike any four hours I’ve experienced before. The roads are fairly empty, flat, and straight, meaning you can cover a lot of terrain. Australia is also incredibly big and most of the time you’re travelling through unpopulated landscapes. While it may be only four hours, your mind feels the weight of the distance.

Here’s the one they were looking for!
*Cheilanthes tenuifolia* with lots of little spore babies on the undersides of its leaves.

The dirt road begins to climb into the mountains. We are leaving behind low scrub and big granite rocks that sit on the flat terrain. Ashley knows where we can find the ferns I’m looking for, but he’s never driven this road before. Instead, we’re trusting researchers who came before us. When they explored this area, they took samples of plants that were preserved and stored in museums and universities. By reviewing the carefully labelled collections at these institutions, we can know which places to revisit in hopes of finding the ferns.

Often, however, having been collected before there was GPS, the location information on these samples is not very precise, or the plants may no longer live there, or maybe that area got turned into a parking lot, as happened to me in New Zealand. So, despite careful planning, you may drive five hours one way to come up empty handed.

As we move higher up the mountain, the soil turns redder and sparse eucalyptus forests begin to enclose us. We locate the previous collections coordinates, an area that seems suitable for ferns to grow. We park the truck on the side of the road and get out to look.

We comb 300 feet along the side of the road because these ferns like the edges of forest, and we find nothing. But as we trudge back to the truck, I spot one meager fern hiding behind a creeping vine! It’s high up off the road-cut and I try to scramble up but only manage to pull a muscle in my arm. Ashley is taller, so he climbs partway up a tree and manages to fetch the fern. It’s not the healthiest, only 6 inches tall for a plant that usually grows at least 12 to 14 inches. It’s also not fertile, making it less useful for research, and in pulling it out of the ground, Ashley broke one of its three leaves off. But it’s better than nothing!

This delicate beauty has no name yet. Karla has to compare it to other ferns in the area to know whether it’s just an odd-looking variant or possibly … a new species!

Ashley excels at being a field botanist because he is not one to give up. “We should keep looking,” he says despite the sweat dripping down our faces.

We pile back in and continue up the road. And who could have predicted that just around the bend we would find dozens of tall, healthy looking ferns! There are easily fifty or so plants, each a deep green, the tallest around 12 inches. Many others are at earlier stages of growth, which can be very helpful for scientists in understanding how plants develop. We take four or five plants, enough to leave a sample at the university in Cairns and for the rest to be shipped back to the US. One sample will be kept at Duke, and the others will be distributed amongst other museums and universities as a type of insurance.

The long hours, the uncertainty, and the harsh conditions become small things when you hit a jackpot like this. Plus, being out in remote wilderness has its own soothing charm, and chance also often allows us to spot cool animals, like the frilled lizard and wallaby we saw on this trip.

Funding for this type of fieldwork is becoming increasingly rare, so I am grateful to the National Geographic Society for seeing the value in this work and funding my three-week expedition. I was able to cover about 400 miles of Australia from north to south, visiting twenty-four different sites, including eight parks, and ranging from lush rainforest to dry, rocky scrub. We collected fifty-five samples, including some that may be new species, and took careful notes and photographs of how these plants grow in the wild, something you can’t tell from dried-up specimens.

Knowing what species are out there and how they exist within the environment is important not only because it may provide solutions to human problems, but also because understanding what biodiversity we have can help us take better care of it in the future.

Guest Post by graduate student Karla Sosa

Malaria Hides In People Without Symptoms

By Anna Gotskind

On November 11, 2019

In Biology, Field Research, Genetics/Genomics, Global Health, Science Communication & Education, Students

It seems like the never-ending battle against Malaria just keeps getting tougher. In regions where Malaria is hyper-prevalent, anti-mosquito measures can only work so well due to the reservoir that has built up of infected humans who do not even know they carry the infection.

In high-transmission areas, asymptomatic malaria is more prevalent than symptomatic malaria. Twenty-four percent of the people in sub-Saharan Africa are estimated to harbor an asymptomatic infection, including 38 to 50 percent of the school-aged children in western Kenya. Out of the 219 million malaria cases in 2017 worldwide, over 90% were in sub-Saharan Africa.

Using a special vacuum-like tool, Kelsey Sumner, a former Duke undergraduate now completing her Ph.D. at UNC-Chapel Hill, collected mosquitoes in households located in rural western Kenya. These weekly mosquito collections were a part of her pre-dissertation study on asymptomatic, or invisible, malaria. She visited Duke in September to catch us up on her work in Data Dialogue event sponsored by the mathematics department.

Sumner and colleague Verona Liao, in front of a sticky trap for mosquitoes

People with asymptomatic malaria carry the infection but have no idea they do because they do not have any indicators. This is incredibly dangerous because without symptoms, they will not get treated and can then infect countless others with the disease. As a result, people with an asymptomatic infection or infections have become a reservoir for malaria — a place for it to hide. Reservoirs are a group that is contributing to transmission at a higher rate or proportion than others.

Sumner’s study focused on examining the effect of asymptomatic malaria on malaria transmission as well as whether asymptomatic malaria infections would protect a person against future symptomatic infections from the same or different malaria infections. They were particularly looking into Plasmodium falciparum malaria. In Kenya, more than 70% of the population lives in an area with a high transmission of this potentially lethal parasite.

“P. falciparum malaria is very diverse in the region,” she said. “It’s constantly mutating, which is why it’s so hard to treat. But because of that, we’re able to actually measure how many infections people have at once.”

The researchers discovered that many study participants were infected with multiple, genetically-distinct malaria infections. Some carried up to fourteen strains of the parasite.

Participants in the study began by filling out an enrollment questionnaire followed by monthly questionnaires and dried blood spot collections. The project has collected over nearly 3,000 dried blood spots from participants. These blood spots were then sent to a lab where DNA was extracted and tested for P. falciparum malaria using qPCR.

“We used the fact that we have this really diverse falciparum species in the area and sequenced the DNA from falciparum to actually determine how many infections people have,” Sumner said. “And then, if there’s a shared infection between humans and mosquitoes.”

Sumner and her team also visited symptomatic participants who would fill out a behavioral questionnaire and undergo a rapid diagnostic test. Infected participants were able to receive treatment.

While people in the region have tried to prevent infection through means like sleeping under insecticide-treated nets, malaria has persisted.

One of the Kenyan staff members hanging a CDC light trap for mosquitoes

Sumner is continuing to analyze the collected DNA to better understand asymptomatic malaria, malarial reservoirs and how to best intervene to help stop this epidemic.

“We’re basically looking at how the number of shared infections differ between those that have asymptomatic malaria versus those that have symptomatic malaria.”

She and her team hypothesize that there are more asymptomatic infections that would result in and explain the rapid transmission of malaria in the region.

Post by Anna Gotskind

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