Tennessee High School Students’ Work at UT Published in Top Science Journal

Two Tennessee high school students have now done what many scientists strive for: publishing their research in a top science journal.

Hayes Griffin (left) and Dalton Chaffee (right) present their award-winning research at the international meeting of the Society for Mathematical Biology. Photo credit: NIMBioS

Hayes Griffin (left) and Dalton Chaffee (right) present their award-winning research at the international meeting of the Society for Mathematical Biology. Photo credit: NIMBioS

Dalton Chaffee and Hayes Griffin worked with mentor R. Tucker Gilman, a former postdoctoral research fellow at the National Institute for Mathematical and Biological Synthesis (NIMBioS) at UT to study mate choice.

Their work was published this week in the journal Evolution.

The students began their research between their junior and senior years at Bearden High School in Knoxville. They wanted to know why individuals choose the mates they choose.

Using a combination of analytical models and mathematical simulations, Chaffee and Griffin made several important discoveries that shed new light on how mate choice is influenced by “sexual imprinting,” a process whereby individuals express preference for mates with traits similar to their mothers, to their fathers or to other adult members in their population. It is known from field studies that females of many species are choosier about mating partners than males are.

“Sexual imprinting is common in nature, but different species do it different ways, and how it evolves is poorly understood,” said Gilman. “Dalton and Hayes wanted to know why different species would evolve to imprint on different individuals.”

The research showed that if the apparatus females use to identify and select their preferred mates requires a lot of evolutionary effort to maintain—for example, if they must have special cells in their eyes to see male colors—then sexual imprinting will not evolve. This suggests that a complex apparatus used for sexual imprinting must evolve initially for some other reason, such as to avoid predators.

When imprinting does evolve, females will choose mates like their fathers—which increases the likelihood of viable offspring and sons that are sexually attractive to females, as the fathers were to the mothers.

In situations where the father is absent, females can evolve to imprint on their mothers or on randomly selected adult males. This kind of imprinting allows females to select mates that will give them viable offspring, but it doesn’t guarantee that these offspring, particularly sons, will be sexually attractive like the females’ fathers were to the mothers.

Chaffee said that he and Griffin spent about twenty hours each week on the project, including reading reams of biological studies about sexual imprinting and learning how to use sophisticated computer programming to run their simulations.

“Just reading was extremely difficult, as much of the jargon and format were completely unfamiliar and very complex,” he said.

Gilman said he was impressed with the students’ drive and initiative.

“Dalton and Hayes needed very little guidance and demonstrated a great deal of commitment to the project,” said Gilman, now a faculty member at the University of Manchester, UK. “Their results explain something completely new about the way mate choice and sexual selection work, and will motivate future work in these fields. That is quite an achievement for scientists at any level.”

The research won a regional finalist award last year in the nationwide Siemens Competition in Math, Science and Technology and was also presented at the international meeting of the Society for Mathematical Biology in 2012. For more information about the study, visit www.nimbios.org/press/FS_highschool.

This fall, Chaffee will be a freshman at Purdue University and Griffin will be a freshman at Duke University.

The National Institute for Mathematical and Biological Synthesis (NIMBioS) brings together researchers from around the world to collaborate across disciplinary boundaries to investigate solutions to basic and applied problems in the life sciences.

To learn more, visit www.nimbios.org.


Whitney Heins (865-974-5460, wheins@utk.edu)

Catherine Crawley (865-974-9350, ccrawley@nimbios.org)