Honors Theses


Karolyn Hansen



Publication Date

Spring 4-2014

Document Type

Honors Thesis


I investigated the responses to specific concentrations of indole in the adult stage of Lucilia sericata, the common green bottle fly. Indole is a commonly used attractant at concentrations between 0 and .04% that has a floral scent at low concentrations and a fecal odor at high concentrations (Cragg, 1950). There were three treatment cages: one all male, one all female, and one mixed male and female. The purpose of these conditions was to observe the difference between sensory responses of males, non-mated females, and mated females. All cages were placed in an incubator to maintain uniform temperatures and light cycles. All treatment cages also received the identical diet to reduce extraneous variables. I measured the response to a concentration gradient of indole through the use of the electroantennogram, an instrument that records electrical depolarizations occurring in the antennae of the specimen being studied when exposed to

specific volatiles. Positive controls and negative controls were used to establish a baseline for responses; the results using the treatment volatile indole were compared to these controls. I hypothesized that the responses of males, non-mated females, and mated females would differ from one other due to their different dietary needs. The males were expected to respond to the lower concentrations of indole; the non-mated females to lower and higher concentrations almost equally; and the mated females to lower concentrations and strongly to higher concentrations. Although responses were not as distinct as expected, the data follows the general trend of the responses predicted.

Permission Statement

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Undergraduate research


Life Sciences | Medicine and Health Sciences