Category: Entomology and Wildlife Ecology
UD graduate course takes a bite into Delaware mosquito genes
April 17, 2025 Written by Katie Peikes | Photos by Jeremy Wayman
Laura Kwasnoski wanted to brush up her training on animal genetics and dive into how animals’ genes get passed down over generations.
It had been five years since she completed her undergraduate degree in biology with a minor in geoscience at a small liberal arts college. Like most technologies, the genetics field has seen some major advancements in that time.
In her first year as a master’s student at the University of Delaware, Kwasnoski, who is studying the mosquito-borne disease avian malaria in raptors, found the perfect course for herself: Molecular Ecology (ENWC 867).
“It was a great refresher,” Kwasnoski said. “I even learned about a whole bunch of new stuff you can do with genetics that I didn’t know about before, things barely touched on as an undergrad.”
Molecular Ecology, first taught in Fall 2023, used a hybrid approach of textbook learning and laboratory work to help students understand how to study animal population genetics and deduce what genes can reveal about a population. The course focused on mosquitoes, but the techniques used to analyze their genes easily translated over to Kwasnoski’s research on raptors.
Led by Vincenzo Ellis, an assistant professor in the University of Delaware’s Department of Entomology and Wildlife Ecology, students dive into genetic data to answer questions about organisms and their responses to the environments they live in. The students also got direct experience analyzing mosquito genetic data at the UD DNA Sequencing and Genotyping Center.
“Genes can tell us a lot of interesting things,” Ellis said. “They can tell us historically whether a population is expanding or contracting over long periods of time. They can tell us how populations are evolving and adapting to their environments.”
Fall 2023 was the first time Ellis taught ENWC 867. Only Kwasnoski and Ph.D. student in wildlife ecology and conservation Scarlet Shifflett registered, but Ellis is hoping to see more interest next time he offers the course in Fall 2025.
“I want students to become well-versed in modern techniques in molecular ecology,” Ellis said. “How can we use molecular methods to answer ecological and evolutionary questions and questions about conservation biology?”
For Shifflett, who was a first-year Ph.D. student in wildlife ecology and conservation at the time of the Fall 2023 course, Molecular Ecology was an exciting opportunity to focus on molecular sciences within wildlife.
“I'm interested in using molecular techniques for diseases,” Shifflett said, “because it can give me a better idea of what’s going on in the evolutionary pathways of diseases within their hosts.”
Shifflett, who completed her undergraduate and master’s degrees at UD, said Molecular Ecology was the most applied course she had ever taken.
‘A box full of bugs’
Molecular Ecology got funding through the UD Department of Entomology and Wildlife Ecology and the Centers for Disease Control and Prevention. Biomedical research organization Delaware INBRE also contributed funding, allowing Kwasnoski and Shifflett to receive hands-on training in DNA sequencing with researchers Erin Bernberg and Mark Shaw at the UD DNA Sequencing and Genotyping Center.
University of Delaware master’s student Wil Winter who is also an environmental scientist with the Delaware Division of Fish and Wildlife set traps around the state for mosquitoes. He brought the traps to Townsend Hall, and the students used microscopes to identify the species of mosquitoes they had.
“When they came to me, they had a box full of bugs,” said Bernberg, a senior scientist with the UD DNA Sequencing and Genotyping Center. “We needed to do something with this. They needed the DNA from them. So I helped them establish an efficient way for them to be able to extract the DNA and check which species they had.”
The original plan of the course was to target the mosquito species Culex pipiens, but the box of bugs contained more of the species Culex salinarius, a vector of West Nile Virus similar to Culex pipiens.
INBRE funders allowed them to move forward with the different species.
Bernberg said ENWC 867 presented an exciting and unique opportunity for the sequencing and genotyping center. Normally, people drop samples off at her lab and then leave. But Kwasnoski and Shifflett got to see and do everything firsthand.
“It’s a lot of work by a lot of people that have very specific skills,” Bernberg said. “To get a hands-on kind of idea of what that is, it’s rare.”
New questions for next fall
Ellis and his students didn’t piece the whole puzzle together in the Fall 2023 semester. They made a lot of progress but ran out of time.
After the course, Ellis, the sequencing center, the Center for Bioinformatics and Computational Biology, and Delaware INBRE came together to finish analyzing the genes and answer questions about their population.
They worked together to sequence the full genomes of 21 mosquitoes from two New Castle County sites as well as from Prime Hook National Wildlife Refuge in Southern Delaware. An initial analysis by Jaysheel Bhavsar, a researcher from the bioinformatics center, identified two genetic groups that were present in both Northern and Southern Delaware and one mosquito that was likely a hybrid of the two groups in Prime Hook.
“I have no idea what that means,” Ellis said.
It opens up a lot of questions, including: How do these groups differ? How different are they? Can scientists figure out how they split apart? Are there more than one species here that we’re not aware of?
Ellis hopes to resolve these questions with his next batch of students. He will work to get the bioinformatic analysis into an accessible format to serve as a roadmap for the students who take the course next fall.
“From the start of the course they’ll be able to work on describing the population genetics of Culex salinarius across Delaware,” Ellis said.
He said the Fall 2025 course will use the same textbook as 2023, and have a lab component similar to two years ago.
Ellis hopes the Fall 2025 course will generate enough buzz and that students will get the full experience of readings, hands-on lab work, and a full understanding of why the field of molecular ecology is important.
“Having a project that’s farther along where the data are generated, the analysis has been started, there’s still another big piece to do which is trying to make more inferences about the populations from the data,” Ellis said. “Can we learn more about the populations from the data we have?”