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The bean beetle ( Callosobruchus maculatus) is native to regions of Africa and Asia (Barbosa, 2022). Inseminated female bean beetles oviposit (lay) their eggs on beans, and their larvae must feed, grow, and mature in the selected bean. Her larvae’s success is based on the bean’s quality. The bean’s quality is measured by size and nutritious value. In previous research, these beetles have been known to be selective in the type and size of bean they choose to oviposit on (Cope and Fox, 2003). Bean beetles are an excellent organism of study in determining oviposition behavior. All feeding is done in the larval stage of development, and adults do not require food or water (Mitchell, 1975). Due to the known selective behavior of bean beetles in previous research, we decided to run an experiment to determine if the moisture of beans affected the oviposition behavior of the bean beetle. 

This experiment used sedentary (flightless) female bean beetles to determine if moisture influenced oviposition behavior. The beans chosen for this study were kidney beans due to their darker color and uniform size; the dark color of the bean allowed for ease in counting white eggs on the bean surface. Additionally, the uniform size of kidney beans decreased variability in our experiment. Beans with increased moisture provided more water for the larvae, whereas the dry beans did not. We therefore predicted that beetles would show a preference for moist beans due to the increased water availability. We hypothesized that if the beans were moister, we would find a more significant number of eggs on the wet bean’s surface than the dry bean. 

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