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  • UC Riverside
  • College of Natural and Agricultural Sciences

Debra A. Lewkiewicz

Debra A. Lewkiewicz

Ph.D., Ecology and Evolutionary Biology
B. A., Biology, Vassar College, 1999

Faculty advisor: Marlene Zuk

Research interests: I am interested in the trade-offs between survival and reproduction that are involved when males signal for mates. In several species of field crickets in the genus, Gryllus, males form aggregations at night when they call for females. One hypothesis to explain this phenomenon is that forming groups helps decrease predation/ parasitism risk. Other hypotheses involve female preference for grouped males, clumped resources attracting males and/ or females into aggregations, and clumped female emergence or oviposition sites attracting groups of males. My research will attempt to explain why males tend to aggregate, and why there is so much variation in aggregating tendencies among males. Specifically, I will attempt to determine: (1) the natural spacing pattern of male Gryllus vocalis, (2) the effect of perceived reproductive opportunity on male spatial pattern, (3) the effect of perceived predation/ parasitism risk on male spatial pattern and on female preference for clumped or dispersed males, (4) how differences in call quality affect both males' willingness to form groups and females' preference for clumped versus isolated males, and (5) how the costs and benefits of aggregation differ for males of different quality.


Fritz, R. S., C. G. Hochwender, D. A. Lewkiewicz, S. Bothwell, and C. M. Orians. 2001. Seedling herbivory by slugs in a willow hybrid system: developmental changes in damage, chemical defense, and plant performance. Oecologia. 129 (1): 87-97