Discipline: Biological Sciences
Alexi Meltel - University of Hawaii at Manoa
Co-Author(s): Adrea Gonzalez-Karlsson, University of California, Los Angeles, CA
Butterflies are among the many animals that have sex-specific resource uses due to the difference in life history between males and females. In the subfamily Ithomiinae, male and female butterflies use pyrrolizidine alkaloids as defense mechanisms and males give females these alkaloids during mating. Both males and females also use nitrogen but the females’ demands for nitrogen are thought to be higher because of egg production. While both sexes use alkaloids, it is the males who go out to seek them. The reason for this is thought to be because females are usually bigger than males and differences in size can make one sex more vulnerable to predation than the other. We hypothesized that there was a sex-specific use of resources in Ithomiine butterflies. Butterflies were caught at the Las Cruces Biological Station in Costa Rica and tested with a nectar and bird dropping test. Weight of nectar consumed with and without alkaloids was compared between sexes. Bird dropping tests involved presenting butterflies with bird droppings and timing latency to proboscis extension and feeding time. Results revealed that males drank more nectar with alkaloids than females, and that both genders fed on bird droppings for equivalent lengths of time but females extended their proboscis more quickly. For future directions, this study could be replicated, but on specific species of Ithomiines and for a longer period of time. Studies like this will provide a better understanding of Ithomiine resource use, and their behavior in general.
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Funder Acknowledgement(s): I thank the Native American and Pacific Islander Research Experience for the opportunity to conduct this research. I thank my mentor, Dr. Adrea GonzalezKarlsson for her guidance and support. I also thank Jeromalyn Santos and Katherine Wilkinson for their help in the field. This program was funded by: NSF; LSAMP- Organization for Tropical Studies.
Faculty Advisor: Kelsea Hosoda,