As Plainview Old-Bethpage High School senior Hannah Stewart prepares to ship off to Brandeis University in the fall, she, like most young adults here age, will remember the best parts of high school: spirit week, homecoming, prom and, of course, gathering lizards and ticks in northern New Jersey.
The science-minded senior recently worked under the auspices of Dr. Russell Burke, chair of the Biology Department at Hofstra University, in a research project with the goal of finding out why cases of Lyme Disease are so prevalent here in the north, but so rare down south.
“This is a part of biology that Dr. Burke introduced me to that I never thought about, working with lizards and insects,” said Stewart. “It was far more interesting than I ever thought it could be.”
For her efforts with Burke, Stewart received a third place award for a research project, titled “Host Preference of Wild Northern and Southern Ixodes scapularis,” at the International Science and Engineering Fair in Los Angeles in May. Hannah additionally tied for first place in the Behavioral and Social Sciences Division of the 2014 Long Island Science & Engineering Fair.
Her research with Burke involved a laboratory study of the black-legged tick and the spread of Lyme Disease. Burke’s lab has been exploring the ecology of Lyme disease since 2007, focusing on the role that lizards play in reducing the prevalence of the disease.
Stewart’s summer 2013 work explored the leading hypothesis that attempts to explain why human cases of Lyme disease are so much more common in the northern U.S. than in the south, although both the necessary ticks and bacteria occur throughout both areas.
This hypothesis is based on the observation that ticks in the south often feed on different animal host species than ticks in the north. Stewart tested whether ticks choose their hosts randomly or whether ticks from different places have different host preferences. Her work showed that both northern and southern black-legged ticks preferred lizard hosts over mammal hosts, and therefore they only feed on mammals in the north when there are no lizards available.
“We found that lizards are crummy hosts for the Lyme disease bacteria,” said Burke. “Down south, lizards don’t pass on Lyme disease and this keeps the rate of the disease low. Hannah did some experiments to find out whether ticks actually prefer to feed off of lizards or mice, and her work shows that ticks, if given the choice, will choose to feed off of lizards. Her work will help us move forward with our studies in our effort to understand the spread of this disease.”
Burke said he received an email from Stewart requesting an opportunity to work in his lab. In these independent research projects, Burke chooses students that boast a high interest in biology and perform well in school. Burke said Stewart was impressive on both counts.
“She also had an interest in wildlife, which is very important to this study,” said Burke. “Biology students are usually headed toward med school, which is fine. But my lab works with wild animals and I needed someone who could be outside. I’ve had pre med types who go outside, get one mosquito bite and they’re done. Not Hannah, she was fully emeresed.
Stewart learned about Burke after some Internet research turned up work he had done in Jamaica Bay studying the effect of Hurricane Sandy on the diamondback terrapin turtle population. Burke’s research appealed to Stewarts love of the outdoors and getting her hands dirty working in the field.
“I really love being outside and I love water sports like stand-up paddle boarding,” she said. “I was once given a chance to go to New Orleans and camp for a week with 19 other students. We saw first hand recovery work after Hurricane Katrina. I just love bieng in field instead of being in white-walled lab all day.”
This college-bound scientist’s enthusiasm inspired Burke, who said more young women should delve into the world of science.
“The world has been a bit biased in regards to females in the sciences. They are far too underused,” he said. “And like most young people, Hannah has a fresh outlook and asked interesting questions. Science needs young people; they are very creative, open to all possibilities and they don’t know what can’t be done.”
For Stewart, working long hours watching ticks choose lizards over mice was rewarding — and it was the first step in her post-high school science career.
“I did this work for five hours per day for six weeks over the summer,” said Stewart. “There was a lot of time observing and taking measurements, but it was a blast working with Dr. Burke.”
