Graduate STEM Fellow Profile

Nathan Frank

Project Title: Transforming Experiences
Thesis: Trophallaxis and hydrocarbon exchange in the pavement ant, Tetramorium caespitum
College/University: University of Colorado Denver
Research Advisor: Michael Greene
Degree Sought: M.S. Integrative Biology
Department: Department of Integrative Biology
Research Focus: Behavior and Chemical Communication in Social Insect Species
Teaching Partner(s):

Description of Research

Social insect colonies use many different modes of communication to modify and optimize colony behavior. We examine the ways in which ants of the species Tetratmorium caspitum use cuticular hydrocarbons as a mode of defining colony affiliation both within and among colonies. These long chain hydrocarbon molecules are present on the exterior surface, or cuticle, of the insects and were originally thought to have evolved for waterproofing and anti-desiccation purposes. Over time these compounds were co-opted for use as recognition signals as colonies developed their own specific combinations of hydrocarbons that define that colony’s signature odor. Ants will adjust their behavior upon encountering one another according to weather or not an encountered individual displays a similar or foreign hydrocarbon profile. My research focuses on how the colony-specific odor is maintained using trophallaxis (oral exchange of nutrients among colony mates).

Example of how my research is integrated into my GK-12 experience

To give the students an example of the self-organizing behavior observed in ant colonies, we engaged them in an exercise that demonstrated how organization can still occur in the absence of an organizing entity. Students were all given three pennies and asked to walk about the room like ants encountering one another. Upon encounter, they were to follow two rules: 1) If one person had more pennies than the other, the person with more pennies received one from the person with fewer pennies. 2) If both individuals had the same number of pennies, a coin toss would determine who gave up a penny. After some time, this exercise results in all the pennies accumulating with one student. The students are then guided to the fact that no decision was ever made to accumulate pennies with one student or in any place at all. Since we all followed the same rules, we created a positive feedback loop that resulted in a defined functional pattern like ants gathering food.