Publication Date


Document Type


First Advisor

King, Bethia H.

Degree Name

B.S. (Bachelor of Science)

Legacy Department

Department of Biological Sciences


A parasitoid that can learn cues associated with the host microenvironment should have an increased chance of future host location and thereby increase its reproductive success. This study examines associative learning in response to simultaneous exposure to the colors yellow and blue in mated females of the parasitoid wasp Nasonia vitripennis. Preference was measured as the proportion of time spent on a color. When trained with one color rewarded with hosts and honey and the other unrewarded, females showed an increase in preference for the rewarded color with increasing number of training days (1,3, and 7 days). Hosts were a more effective reward than honey, although both produced a significant preference toward the rewarded color. Hosts and honey together were slightly more effective than just hosts. When individuals were trained with a variable versus constant daily reward there was a preference for the color associated with the variable reward when it was yellow, but not when it was blue. When comparing the preference of the constant versus variable reward and constant versus no reward, the presence of a variable reward decreased the strength of preference toward the constantly rewarded color. Finally, individuals trained with a positive and negative reward preferred the positively rewarded color when it was blue but showed no preference in the reverse situation. When blue was the positively rewarded, the presence of a negative reward versus no reward did not increase the strength of preference toward the positively rewarded color.


Includes bibliographical references.


28 pages




Northern Illinois University

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