Bryan Falk: Parsing Parasites in Anole Lizards
by AMNH on
On September 30, 2013, the first graduates of the Richard Gilder Graduate School will receive Doctor of Philosophy degrees in Comparative Biology at the inaugural commencement for the first Ph.D.-granting program for any museum in the Western hemisphere. We're profiling the newly minted Ph.D.s this week.
In his Idaho elementary school, Bryan Falk was regularly sent to the principal’s office, not for passing notes or being tardy, but for getting too close to the off-limits irrigation ditch at the back of the schoolyard. During recess, Falk couldn’t resist catching garter snakes and tree frogs there and sneaking them back home in his lunchbox. By the time he graduated high school, Falk kept a substantial reptile and amphibian collection, was active in his local herpetological society, and had plans to attend veterinary school. But during college, a study-abroad course in Costa Rica on tropical ecology redirected his career path toward scientific research, in particular, the study of parasites.
“I was an undergrad when I learned that lizards got malaria, which I thought was really neat, and I realized that Caribbean anole lizards and their malarial parasites would be a good system to work on,” says Falk. As part of the first class in the Comparative Biology doctoral program at the Richard Gilder Graduate School (RGGS), Falk spent four years exploring these parasites under the guidance of Susan Perkins, an associate professor in RGGS and an associate curator in the Museum’s Division of Invertebrate Zoology and Sackler Institute for Comparative Genomics.
“Parasites are really common—about a third of all living animals are parasitic—but we don't have a good understanding of how all those species came about,” Falk said.
The goal of Falk’s dissertation research was to better understand parasite diversity. This included collecting new specimens during fieldwork in locations including the Dominican Republic, Madagascar, Mexico, and Florida, and investigating how parasites with different modes of transmission give rise to new populations and species. His research suggests that multiple factors contribute to parasite diversification and that the great variation in parasite traits—such as life cycle complexity and number of hosts—begets species diversity.
“I showed that the pattern of diversification in a widespread lizard malaria parasite group is very similar to the unusual patterns observed in a human malaria parasite,” Falk said. “These patterns were once considered to be the result of coevolution with us, the parasite’s hosts. Instead, my research suggests that malaria parasite diversification is shaped through the parasites’ life cycle and low prevalence, and that malaria parasites of wildlife may serve as models to study the evolution of those affecting humans.”
Falk received his bachelor’s degree in biology from Portland State University. He successfully defended his Ph.D. dissertation on January 10, 2013, and continued to study Caribbean lizard parasites at the Museum as a postdoctoral research associate in the Sackler Institute for Comparative Genomics. Falk recently started developing research-based courses for high school students at the Museum, New York University, Black Rock Forest Consortium, and Cold Spring Harbor Laboratory.
Read more profiles of the graduates on the Museum's blog.
Click here to read more about the Richard Gilder Graduate School.